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1
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Kimura AH, Dahmer D, Isawa LA, da Silva ABO, Souza LMDS, Takata PH, Scandorieiro S, Deonas AN, Germiniani-Cardozo J, Vespero EC, Perugini MRE, Lincopan N, Garcia Lonni AAS, Nakazato G, Kobayashi RKT. Hydrogel Containing Biogenic Silver Nanoparticles and Origanum vulgare Essential Oil for Burn Wounds: Antimicrobial Efficacy Using Ex Vivo and In Vivo Methods Against Multidrug-Resistant Microorganisms. Pharmaceutics 2025; 17:503. [PMID: 40284498 PMCID: PMC12030619 DOI: 10.3390/pharmaceutics17040503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2025] [Revised: 04/07/2025] [Accepted: 04/07/2025] [Indexed: 04/29/2025] Open
Abstract
Background/Objectives: Wounds from burns are susceptible to infections, allowing multidrug-resistant microorganisms to complicate treatments and patient recovery. This highlights the development of new strategies to control these microorganisms. This work evaluated the antibacterial activity of hydrogels containing biogenic silver nanoparticles (bio-AgNP) and Origanum vulgare essential oil (OEO) against multidrug-resistant bacteria. Methods: The formulations were subjected to organoleptic, pharmacotechnical, and stability characterization and antimicrobial activity assessment by time-kill tests and alternative methods, an ex vivo model using porcine skin, and an in vivo model using Galleria mellonella. Results: All hydrogels maintained their stability after the thermal stress. The hydrogel containing bio-AgNP + OEO 1% (HAgNP + OEO1) presented bactericidal effectiveness, within 2 h, against both Gram-positive and Gram-negative multidrug-resistant bacteria in the time-kill test. For alternative testing, HAgNP + OEO1 was compared with 1% silver sulfadiazine (SS) and the base formulation. In the ex vivo test, both HAgNP + OEO1 and SS treatments showed a similar reduction in superficial washing of the burn for S. aureus 999, while for P. aeruginosa, the reduction was more expressive for SS treatment. In the burn tissue, HAgNP + OEO1 treatment was more effective against S. aureus 999, while for P. aeruginosa 1461, both formulations were similarly effective. In the Galleria mellonella test, survival rates after 48 h were 84% for the control group (base) and 50% for both HAgNP + OEO1 and SS treatment groups. Conclusions: This study demonstrates that the hydrogel combining antimicrobials is effective against multidrug-resistant microorganisms, offering a promising alternative for the treatment of infected burns.
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Affiliation(s)
- Angela Hitomi Kimura
- Laboratory of Basic and Applied Bacteriology, Department of Microbiology, Center of Biological Sciences, State University of Londrina, Londrina 86057-970, Brazil; (A.H.K.); (L.A.I.); (A.B.O.d.S.); (L.M.d.S.S.); (P.H.T.); (G.N.)
| | - Débora Dahmer
- Department of Biochemistry and Biotechnology, State University of Londrina, Londrina 86057-970, Brazil; (D.D.); (A.N.D.); (J.G.-C.)
| | - Luana Ayumi Isawa
- Laboratory of Basic and Applied Bacteriology, Department of Microbiology, Center of Biological Sciences, State University of Londrina, Londrina 86057-970, Brazil; (A.H.K.); (L.A.I.); (A.B.O.d.S.); (L.M.d.S.S.); (P.H.T.); (G.N.)
| | - Ana Beatriz Olivetti da Silva
- Laboratory of Basic and Applied Bacteriology, Department of Microbiology, Center of Biological Sciences, State University of Londrina, Londrina 86057-970, Brazil; (A.H.K.); (L.A.I.); (A.B.O.d.S.); (L.M.d.S.S.); (P.H.T.); (G.N.)
| | - Lucas Marcelino dos Santos Souza
- Laboratory of Basic and Applied Bacteriology, Department of Microbiology, Center of Biological Sciences, State University of Londrina, Londrina 86057-970, Brazil; (A.H.K.); (L.A.I.); (A.B.O.d.S.); (L.M.d.S.S.); (P.H.T.); (G.N.)
| | - Pedro Henrique Takata
- Laboratory of Basic and Applied Bacteriology, Department of Microbiology, Center of Biological Sciences, State University of Londrina, Londrina 86057-970, Brazil; (A.H.K.); (L.A.I.); (A.B.O.d.S.); (L.M.d.S.S.); (P.H.T.); (G.N.)
| | - Sara Scandorieiro
- Laboratory of Innovation and Cosmeceutical Technology, Department of Pharmaceutical Sciences, Center of Health Sciences, University Hospital of Londrina, Londrina 86038-350, Brazil; (S.S.); (A.A.S.G.L.)
| | - Anastácia Nikolaos Deonas
- Department of Biochemistry and Biotechnology, State University of Londrina, Londrina 86057-970, Brazil; (D.D.); (A.N.D.); (J.G.-C.)
| | - Jennifer Germiniani-Cardozo
- Department of Biochemistry and Biotechnology, State University of Londrina, Londrina 86057-970, Brazil; (D.D.); (A.N.D.); (J.G.-C.)
| | - Eliana Carolina Vespero
- Department of Pathology, Clinical and Toxicological Analysis, Center of Health Sciences, University Hospital of Londrina, Londrina 86038-350, Brazil; (E.C.V.); (M.R.E.P.)
| | - Marcia Regina Eches Perugini
- Department of Pathology, Clinical and Toxicological Analysis, Center of Health Sciences, University Hospital of Londrina, Londrina 86038-350, Brazil; (E.C.V.); (M.R.E.P.)
| | - Nilton Lincopan
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-900, Brazil;
| | - Audrey Alesandra Stinghen Garcia Lonni
- Laboratory of Innovation and Cosmeceutical Technology, Department of Pharmaceutical Sciences, Center of Health Sciences, University Hospital of Londrina, Londrina 86038-350, Brazil; (S.S.); (A.A.S.G.L.)
| | - Gerson Nakazato
- Laboratory of Basic and Applied Bacteriology, Department of Microbiology, Center of Biological Sciences, State University of Londrina, Londrina 86057-970, Brazil; (A.H.K.); (L.A.I.); (A.B.O.d.S.); (L.M.d.S.S.); (P.H.T.); (G.N.)
| | - Renata Katsuko Takayama Kobayashi
- Laboratory of Basic and Applied Bacteriology, Department of Microbiology, Center of Biological Sciences, State University of Londrina, Londrina 86057-970, Brazil; (A.H.K.); (L.A.I.); (A.B.O.d.S.); (L.M.d.S.S.); (P.H.T.); (G.N.)
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Kochan K, Jiang JH, Kostoulias X, Lai E, Richardson Z, Pebotuwa S, Heraud P, Wood BR, Peleg AY. Fast and Accurate Prediction of Antibiotic Susceptibility in Clinical Methicillin-Resistant S. aureus Isolates Using ATR-FTIR Spectroscopy: A Model Validation Study. Anal Chem 2025; 97:6041-6048. [PMID: 40063694 DOI: 10.1021/acs.analchem.4c06086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/26/2025]
Abstract
Diagnosing antimicrobial resistance (AMR) remains critical for improving patient survival rates and treatment outcomes. Current antibiotic susceptibility tests (AST) suffer prolonged turnaround times, necessitating a minimum of 24 h for results. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy emerges as a promising phenotypic testing method in bacteriology due to its rapid chemical characterization capability. Here, we present an innovative approach utilizing ATR-FTIR spectroscopy for rapid AMR assessment, distinguishing between methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-susceptible S. aureus (MSSA). Our approach focuses on detecting early markers of effective antibiotic action and using these to predict resistance profiles. To identify the earliest time for detection, five MSSA and five MRSA strains were subjected to oxacillin exposure for up to 2 h. We observed discernible molecular changes arising in MSSA as early as 1 h after exposure to oxacillin, which were absent in MRSA strains. Bands at 1624 and 1515 cm-1 were identified as markers of positive drug response in MSSA using principal component analysis (PCA) and were associated with peptidoglycan precursor accumulation upon transpeptidation inhibition. To develop predictive models for determining resistance profiles, we implemented ML-based modeling of the spectral data, reflective of the oxacillin-induced chemical composition changes in MSSA and MRSA. Partial least squares discriminant analysis (PLS-DA) and support vector machines classification (SVM-C) algorithms produced the best results, achieving 100% consistency with minimum inhibitory concentration (MIC) classification. Our models were independently validated by blind testing with 35 clinical strains and demonstrated 100% agreement with resistance profiling determined by MIC. Our study underscores the potential of ATR-FTIR spectroscopy for rapid and accurate AMR assessment, with the capacity to revolutionize diagnostics in combating antibiotic resistance.
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Affiliation(s)
- Kamila Kochan
- School of Chemistry, Faculty of Science, Monash University, Clayton, Victoria 3800, Australia
| | - Jhih-Hang Jiang
- Infection Program, Department of Microbiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
- Department of Infectious Diseases, The Alfred Hospital and School of Translational Medicine, Monash University, Melbourne, Victoria 3004, Australia
- Centre to Impact AMR, Monash University, Clayton, Victoria 3800, Australia
| | - Xenia Kostoulias
- Infection Program, Department of Microbiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
- Department of Infectious Diseases, The Alfred Hospital and School of Translational Medicine, Monash University, Melbourne, Victoria 3004, Australia
- Centre to Impact AMR, Monash University, Clayton, Victoria 3800, Australia
| | - Elizabeth Lai
- School of Chemistry, Faculty of Science, Monash University, Clayton, Victoria 3800, Australia
| | - Zack Richardson
- School of Chemistry, Faculty of Science, Monash University, Clayton, Victoria 3800, Australia
| | - Savithri Pebotuwa
- School of Chemistry, Faculty of Science, Monash University, Clayton, Victoria 3800, Australia
- Infection Program, Department of Microbiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Philip Heraud
- Infection Program, Department of Microbiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Bayden R Wood
- School of Chemistry, Faculty of Science, Monash University, Clayton, Victoria 3800, Australia
| | - Anton Y Peleg
- Infection Program, Department of Microbiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
- Department of Infectious Diseases, The Alfred Hospital and School of Translational Medicine, Monash University, Melbourne, Victoria 3004, Australia
- Centre to Impact AMR, Monash University, Clayton, Victoria 3800, Australia
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Chines E, Vertillo Aluisio G, Santagati M, Mezzatesta ML, Cafiso V. Fitness Burden for the Stepwise Acquisition of First- and Second-Line Antimicrobial Reduced-Susceptibility in High-Risk ESKAPE MRSA Superbugs. Antibiotics (Basel) 2025; 14:244. [PMID: 40149055 PMCID: PMC11939686 DOI: 10.3390/antibiotics14030244] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2025] [Revised: 02/20/2025] [Accepted: 02/25/2025] [Indexed: 03/29/2025] Open
Abstract
Background: The fitness costs (FCs) of antimicrobial resistance (AMR) are crucial issues in antimicrobial resistance (AMR) onset, spread, and, consequently, public health. In Staphylococcus aureus, AMR can induce significant FCs due to slow growth, low competitiveness, and virulence. Here, we investigated the genomics and FCs emerging for progressively acquiring daptomycin (DAP) and glycopeptide (GLY) reduced susceptibility in MRSA. Methods: Genomics was carried out using Illumina-MiSeq Whole-genome sequencing and bioinformatics. The biological FCs of isogenic MRSA strain pairs progressively acquiring DAP and GLY-reduced susceptibility, under DAP/GLY mono or combined therapy, were performed by in-vitro independent and competitive mixed growth, phenotypic in-vitro virulence analysis, and in-vivo G. mellonella larvae killing. Results: Genomics evidenced four different extremely resistant high-risk clones, i.e., ST-5 N315 HA-MRSA, ST-398 LA-MRSA, ST-22 USA-100 HA-EMRSA-15, and ST-1 MW2 CA-MRSA. In-vitro fitness assays revealed slow growth, lower competitiveness, and reduced virulence, predominantly in Galleria mellonella killing ability, in DAP-S hGISA, DAP-R GSSA, DAP-R hGISA, and DAP-R GISA strains. Conclusions: The occurrence of glycopeptide and daptomycin reduced susceptibility conferred increasing FCs, paid as a gradual reduction in virulence, competitiveness, and slow growth performance.
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Affiliation(s)
- Eleonora Chines
- Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy; (E.C.); (G.V.A.); (M.S.); (M.L.M.)
- PhD National Program in One Health Approaches to Infectious Diseases and Life Science Research, Department of Public Health, Experimental, and Forensic Medicine, University of Pavia, 27100 Pavia, Italy
| | - Gaia Vertillo Aluisio
- Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy; (E.C.); (G.V.A.); (M.S.); (M.L.M.)
| | - Maria Santagati
- Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy; (E.C.); (G.V.A.); (M.S.); (M.L.M.)
| | - Maria Lina Mezzatesta
- Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy; (E.C.); (G.V.A.); (M.S.); (M.L.M.)
| | - Viviana Cafiso
- Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy; (E.C.); (G.V.A.); (M.S.); (M.L.M.)
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Han W, Xiao Y, Shen L, Yuan X, Yu J, Gao H, Hu R, Shi J, Wang B, Zhang J, Zhou P, Wan C, Huang Y, Lv J, Yu F. The roles of cell wall inhibition responsive protein CwrA in the pathogenicity of Staphylococcus aureus. Virulence 2024; 15:2411540. [PMID: 39359063 PMCID: PMC11457683 DOI: 10.1080/21505594.2024.2411540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2024] [Revised: 07/13/2024] [Accepted: 09/05/2024] [Indexed: 10/04/2024] Open
Abstract
The ability to form robust biofilms and secrete a diverse array of virulence factors are key pathogenic determinants of Staphylococcus aureus, causing a wide range of infectious diseases. Here, we characterized cwrA as a VraR-regulated gene encoding a cell wall inhibition-responsive protein (CwrA) using electrophoretic mobility shift assays. We constructed cwrA deletion mutants in the genetic background of methicillin-resistant S. aureus (MRSA) and methicillin-sensitive S. aureus (MSSA) strains. Phenotypic analyses indicated that deletion of cwrA led to impaired biofilm formation, which was correlated with polysaccharide intercellular adhesin (PIA). Besides, the results of real-time quantitative PCR (RT-qPCR) and β-galactosidase activity assay revealed that CwrA promoted biofilm formation by influence the ica operon activity in S. aureus. Furthermore, cwrA deletion mutants released less extracellular DNA (eDNA) in the biofilm because of their reduced autolytic activity compared to the wild-type (WT) strains. We also found that cwrA deletion mutant more virulence than the parental strain because of its enhanced hemolytic activity. Mechanistically, this phenotypic alteration is related to activation of the SaeRS two-component system, which positively regulates the transcriptional levels of genes encoding membrane-damaging toxins. Overall, our results suggest that CwrA plays an important role in modulating biofilm formation and hemolytic activity in S. aureus.
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Affiliation(s)
- Weihua Han
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, People’s Republic of China
| | - Yanghua Xiao
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, People’s Republic of China
| | - Li Shen
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, People’s Republic of China
| | - Xinru Yuan
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, People’s Republic of China
| | - Jingyi Yu
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, People’s Republic of China
| | - Haojin Gao
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, People’s Republic of China
| | - Rongrong Hu
- Shanghai Institute of Immunity and Infection, Chinese Academy of Science, Shanghai, People’s Republic of China
| | - Junhong Shi
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, People’s Republic of China
| | - Bingjie Wang
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, People’s Republic of China
| | - Jiao Zhang
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, People’s Republic of China
| | - Peiyao Zhou
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, People’s Republic of China
| | - Cailing Wan
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, People’s Republic of China
| | - Yu Huang
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, People’s Republic of China
| | - JianBo Lv
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, People’s Republic of China
| | - Fangyou Yu
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai, People’s Republic of China
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Cheng X, Shi Y, Liu Y, Xu Y, Ma J, Ma L, Wang Z, Guo S, Su J. Adaptive physiological and metabolic alterations in Staphylococcus aureus evolution under vancomycin exposure. World J Microbiol Biotechnol 2024; 40:322. [PMID: 39283509 DOI: 10.1007/s11274-024-04128-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2024] [Accepted: 08/31/2024] [Indexed: 10/17/2024]
Abstract
Staphylococcus aureus can develop antibiotic resistance and evade immune responses, causing infections in different body sites. However, the metabolic changes underlying this process are poorly understood. A variant strain, C1V, was derived from the parental strain C1 by exposing it to increasing concentrations of vancomycin in vitro. C1V exhibited a vancomycin-intermediate phenotype and physiological changes compared to C1. It showed higher survival rates than C1 when phagocytosed by Raw264.7 cells. Metabolomics analysis identified significant metabolic differences pre- and post-induction (C1 + SC1 vs. C1V + SC1V: 201 metabolites) as well as pre- and post-phagocytosis (C1 vs. SC1: 50 metabolites; C1V vs. SC1V: 95 metabolites). The variant strain had distinct morphological characteristics, decreased adhesion ability, impaired virulence, and enhanced resistance to phagocytosis compared to the parental strain. Differential metabolites may contribute to S. aureus ' resistance to antibiotics and phagocytosis, offering insights into potential strategies for altering vancomycin nonsusceptibility and enhancing phagocyte killing by manipulating bacterial metabolism.
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Affiliation(s)
- Xin Cheng
- Clinical Laboratory Center, Beijing Friendship Hospital, Capital Medical University, Beijing, 100050, China
| | - Yue Shi
- Clinical Laboratory Center, Beijing Friendship Hospital, Capital Medical University, Beijing, 100050, China
| | - Yadong Liu
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, 101408, China
| | - Yibin Xu
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Jingxin Ma
- Clinical Laboratory Center, Beijing Friendship Hospital, Capital Medical University, Beijing, 100050, China
| | - Liyan Ma
- Clinical Laboratory Center, Beijing Friendship Hospital, Capital Medical University, Beijing, 100050, China
| | - Zerui Wang
- Biomedical Sciences College & Shandong Medical Biotechnology Centre, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, 250117, Shandong, China
| | - Shuilong Guo
- Department of Gastroenterology, Beijing Friendship Hospital, Capital Medical University, Beijing, 100050, China.
| | - Jianrong Su
- Clinical Laboratory Center, Beijing Friendship Hospital, Capital Medical University, Beijing, 100050, China.
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Banfi D, Bianchi T, Mastore M, Brivio MF. Optimization of Experimental Infection of the Animal Model Galleria mellonella Linnaeus 1758 (Lepidoptera: Pyralidae) with the Gram-Positive Bacterium Micrococcus luteus. INSECTS 2024; 15:618. [PMID: 39194822 DOI: 10.3390/insects15080618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2024] [Revised: 08/09/2024] [Accepted: 08/13/2024] [Indexed: 08/29/2024]
Abstract
The aim of this work was to develop an experimental protocol for the infection of Galleria mellonella with Gram-positive bacteria. Some physiological characteristics of these insects are comparable to those of vertebrates, therefore allowing the replacement of mammals in the preclinical phases of drug development. G. mellonella Linnaeus 1758 (Lepidoptera: Pyralidae) is accepted as an alternative model for the study of infectious diseases. Since data on infection procedures with different bacterial strains are scarce and sometimes conflicting, also due to different and non-uniform protocols, we developed an experimental protocol that would allow for controlled and repeatable infections, using the Gram-positive bacterium GRAS (Generally Regarded As Safe) Micrococcus luteus. After analyzing the morphology and defining the growth rate of M. luteus, doses of between 101 and 106 CFU/larvae were administered to late-stage larvae. The survival rate of the larvae was monitored up to 7 days and the LD50 determined. The bacterial clearance capacity of the larvae after injection with 103 and 105 CFU/larvae was assessed by hemolymph bacterial load analysis. The results made it possible to define the growth curve of M. luteus correlated with the CFU count; based on the LD50 (103.8 CFU/larvae) calculated on the survival of G. mellonella, infections were carried out to evaluate the immune efficiency of the larvae in bacterial clearance. This protocol, standardized on G. mellonella larvae, could provide a functional tool to study the course of bacterial infections.
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Affiliation(s)
- Davide Banfi
- Laboratory of Applied Entomology and Parasitology, Department of Theoretical and Applied Sciences (DiSTA), University of Insubria, 21100 Varese, Italy
| | - Tommaso Bianchi
- Laboratory of Applied Entomology and Parasitology, Department of Theoretical and Applied Sciences (DiSTA), University of Insubria, 21100 Varese, Italy
| | - Maristella Mastore
- Laboratory of Applied Entomology and Parasitology, Department of Theoretical and Applied Sciences (DiSTA), University of Insubria, 21100 Varese, Italy
| | - Maurizio Francesco Brivio
- Laboratory of Applied Entomology and Parasitology, Department of Theoretical and Applied Sciences (DiSTA), University of Insubria, 21100 Varese, Italy
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Fait A, Silva SF, Abrahamsson JÅH, Ingmer H. Staphylococcus aureus response and adaptation to vancomycin. Adv Microb Physiol 2024; 85:201-258. [PMID: 39059821 DOI: 10.1016/bs.ampbs.2024.04.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/28/2024]
Abstract
Antibiotic resistance is an increasing challenge for the human pathogen Staphylococcus aureus. Methicillin-resistant S. aureus (MRSA) clones have spread globally, and a growing number display decreased susceptibility to vancomycin, the favoured antibiotic for treatment of MRSA infections. These vancomycin-intermediate S. aureus (VISA) or heterogeneous vancomycin-intermediate S. aureus (hVISA) strains arise from accumulation of a variety of point mutations, leading to cell wall thickening and reduced vancomycin binding to the cell wall building block, Lipid II, at the septum. They display only minor changes in vancomycin susceptibility, with varying tolerance between cells in a population, and therefore, they can be difficult to detect. In this review, we summarize current knowledge of VISA and hVISA. We discuss the role of genetic strain background or epistasis for VISA development and the possibility of strains being 'transient' VISA with gene expression changes mediated by, for example, VraTSR, GraXSR, or WalRK signal transduction systems, leading to temporary vancomycin tolerance. Additionally, we address collateral susceptibility to other antibiotics than vancomycin. Specifically, we estimate how mutations in rpoB, encoding the β-subunit of the RNA polymerase, affect overall protein structure and compare changes with rifampicin resistance. Ultimately, such in-depth analysis of VISA and hVISA strains in terms of genetic and transcriptional changes, as well as changes in protein structures, may pave the way for improved detection and guide antibiotic therapy by revealing strains at risk of VISA development. Such tools will be valuable for keeping vancomycin an asset also in the future.
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Affiliation(s)
- Anaëlle Fait
- Department of Veterinary and Animal Sciences, University of Copenhagen, Frederiksberg, Denmark; Department of Environmental Systems Science, ETH Zürich, Zürich, Switzerland
| | - Stephanie Fulaz Silva
- Department of Veterinary and Animal Sciences, University of Copenhagen, Frederiksberg, Denmark
| | | | - Hanne Ingmer
- Department of Veterinary and Animal Sciences, University of Copenhagen, Frederiksberg, Denmark.
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8
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da Silva JR, Silva JFM, Pereira MF, Torres AR, Gonçalves MS, de Azevedo Prata MC, Vasconcelos Paiva E Brito MA, da Costa GM, Ribeiro JB. Is Galleria mellonella model a good alternative to study virulence in Staphylococcus aureus from bovine mastitis? Braz J Microbiol 2024; 55:889-900. [PMID: 38049660 PMCID: PMC10920502 DOI: 10.1007/s42770-023-01181-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 11/09/2023] [Indexed: 12/06/2023] Open
Abstract
Staphylococcus aureus is one of the agents of bovine mastitis of hardest control due to a complex pathogenesis comprising a variety of virulence factors, which ensures its persistence in the mammary gland, causing significant health and economic losses. Therefore, understanding the pathogenesis of this agent is imperative. Galleria mellonella has stood out as an invertebrate animal model for the study of infectious diseases that affect several hosts. This work aimed to evaluate G. mellonella larvae as an experimental model for the study of virulence phenotypes in an S. aureus population isolated from bovine mastitis. Thirty genetically divergent S. aureus strains were chosen based on PFGE analysis. After experimental infection, larvae survival rates, bacterial growth in hemolymph, melanization intensity of the dorsal vessel, and histological characteristics of the infected tissues were evaluated. The G. mellonella model showed a clear diversity in the S. aureus pathogenicity pattern, allowing the differentiation of strains with virulence phenotypes ranging from high to low degrees. Histological analysis confirmed that the strains tested were capable of inducing the formation of nodules and melanization spots in the dorsal vessels of the larvae in different magnitudes. The strains 16S-717, 19C-828, and 31S-1443 presented the highest virulence intensity among the bacteria tested and will be used further for the generation of S. aureus mutant populations to prospect genetic targets aimed to develop control strategies of bovine mastitis. Altogether, our results suggest that G. mellonella is an attractive and low-cost animal model for characterizing virulence phenotypes of large S. aureus populations.
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Affiliation(s)
- Juliana Rosa da Silva
- Department of Veterinay Medicine, Federal University of Lavras, Lavras, MG, 37200-000, Brazil
| | | | - Monalessa Fábia Pereira
- Department of Biological Sciences, State University of Minas Gerais, Carangola, MG, 36800-000, Brazil
| | | | - Maysa Serpa Gonçalves
- Department of Veterinay Medicine, Federal University of Lavras, Lavras, MG, 37200-000, Brazil
| | | | | | - Geraldo Márcio da Costa
- Department of Veterinay Medicine, Federal University of Lavras, Lavras, MG, 37200-000, Brazil.
| | - João Batista Ribeiro
- Brazilian Agricultural Research Corporation, Juiz de Fora, MG, 36038-330, Brazil.
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Marschall E, Cass RW, Prasad KM, Swarbrick JD, McKay AI, Payne JAE, Cryle MJ, Tailhades J. Synthetic ramoplanin analogues are accessible by effective incorporation of arylglycines in solid-phase peptide synthesis. Chem Sci 2023; 15:195-203. [PMID: 38131086 PMCID: PMC10732013 DOI: 10.1039/d3sc01944f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 09/09/2023] [Indexed: 12/23/2023] Open
Abstract
The threat of antimicrobial resistance to antibiotics requires a continual effort to develop alternative treatments. Arylglycines (or phenylglycines) are one of the signature amino acids found in many natural peptide antibiotics, but their propensity for epimerization in solid-phase peptide synthesis (SPPS) has prevented their use in long peptide sequences. We have now identified an optimized protocol that allows the synthesis of challenging non-ribosomal peptides including precursors of the glycopeptide antibiotics and an analogue of feglymycin (1 analogue, 20%). We have exploited this protocol to synthesize analogues of the peptide antibiotic ramoplanin using native chemical ligation/desulfurization (1 analogue, 6.5%) and head-to-tail macrocyclization in excellent yield (6 analogues, 3-9%), with these compounds extensively characterized by NMR (U-shaped structure) and antimicrobial activity assays (two clinical isolates). This method significantly reduces synthesis time (6-9 days) when compared with total syntheses (2-3 months) and enables drug discovery programs to include arylglycines in structure-activity relationship studies and drug development.
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Affiliation(s)
- Edward Marschall
- Department of Biochemistry and Molecular Biology, The Monash Biomedicine Discovery Institute, Monash University Clayton VIC 3800 Australia
- EMBL Australia, Monash University Clayton VIC 3800 Australia
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Clayton VIC 3800 Australia
| | - Rachel W Cass
- Department of Biochemistry and Molecular Biology, The Monash Biomedicine Discovery Institute, Monash University Clayton VIC 3800 Australia
- EMBL Australia, Monash University Clayton VIC 3800 Australia
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Clayton VIC 3800 Australia
| | - Komal M Prasad
- Department of Biochemistry and Molecular Biology, The Monash Biomedicine Discovery Institute, Monash University Clayton VIC 3800 Australia
- EMBL Australia, Monash University Clayton VIC 3800 Australia
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Clayton VIC 3800 Australia
| | - James D Swarbrick
- Department of Microbiology, Monash University Clayton VIC 3800 Australia
| | - Alasdair I McKay
- Department of Chemistry, Monash University Clayton VIC 3800 Australia
| | - Jennifer A E Payne
- Department of Biochemistry and Molecular Biology, The Monash Biomedicine Discovery Institute, Monash University Clayton VIC 3800 Australia
- EMBL Australia, Monash University Clayton VIC 3800 Australia
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Clayton VIC 3800 Australia
| | - Max J Cryle
- Department of Biochemistry and Molecular Biology, The Monash Biomedicine Discovery Institute, Monash University Clayton VIC 3800 Australia
- EMBL Australia, Monash University Clayton VIC 3800 Australia
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Clayton VIC 3800 Australia
| | - Julien Tailhades
- Department of Biochemistry and Molecular Biology, The Monash Biomedicine Discovery Institute, Monash University Clayton VIC 3800 Australia
- EMBL Australia, Monash University Clayton VIC 3800 Australia
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Clayton VIC 3800 Australia
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10
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Jiang JH, Cameron DR, Nethercott C, Aires-de-Sousa M, Peleg AY. Virulence attributes of successful methicillin-resistant Staphylococcus aureus lineages. Clin Microbiol Rev 2023; 36:e0014822. [PMID: 37982596 PMCID: PMC10732075 DOI: 10.1128/cmr.00148-22] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2023] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is a leading cause of severe and often fatal infections. MRSA epidemics have occurred in waves, whereby a previously successful lineage has been replaced by a more fit and better adapted lineage. Selection pressures in both hospital and community settings are not uniform across the globe, which has resulted in geographically distinct epidemiology. This review focuses on the mechanisms that trigger the establishment and maintenance of current, dominant MRSA lineages across the globe. While the important role of antibiotic resistance will be mentioned throughout, factors which influence the capacity of S. aureus to colonize and cause disease within a host will be the primary focus of this review. We show that while MRSA possesses a diverse arsenal of toxins including alpha-toxin, the success of a lineage involves more than just producing toxins that damage the host. Success is often attributed to the acquisition or loss of genetic elements involved in colonization and niche adaptation such as the arginine catabolic mobile element, as well as the activity of regulatory systems, and shift metabolism accordingly (e.g., the accessory genome regulator, agr). Understanding exactly how specific MRSA clones cause prolonged epidemics may reveal targets for therapies, whereby both core (e.g., the alpha toxin) and acquired virulence factors (e.g., the Panton-Valentine leukocidin) may be nullified using anti-virulence strategies.
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Affiliation(s)
- Jhih-Hang Jiang
- Department of Microbiology, Infection Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
- Department of Infectious Diseases, The Alfred Hospital and Central Clinical School, Monash University, Melbourne, Victoria, Australia
| | - David R Cameron
- Department of Biomedical Research, University of Bern, Bern, Switzerland
| | - Cara Nethercott
- Department of Microbiology, Infection Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Marta Aires-de-Sousa
- Laboratory of Molecular Genetics, Institutode Tecnologia Químicae Biológica António Xavier (ITQB-NOVA), Universidade Nova de Lisboa, Oeiras, Portugal
- Escola Superior de Saúde da Cruz Vermelha Portuguesa-Lisboa (ESSCVP-Lisboa), Lisbon, Portugal
| | - Anton Y Peleg
- Department of Microbiology, Infection Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
- Department of Infectious Diseases, The Alfred Hospital and Central Clinical School, Monash University, Melbourne, Victoria, Australia
- Centre to Impact Antimicrobial Resistance, Monash University, Clayton, Melbourne, Victoria, Australia
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Alnezary FS, Almutairi MS, Alhifany AA, Almangour TA. Assessing Galleria mellonella as a preliminary model for systemic Staphylococcus aureus infection: Evaluating the efficacy and impact of vancomycin and Nigella sativa oil on gut microbiota. Saudi Pharm J 2023; 31:101824. [PMID: 37965487 PMCID: PMC10641552 DOI: 10.1016/j.jsps.2023.101824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 10/10/2023] [Indexed: 11/16/2023] Open
Abstract
Background Staphylococcus aureus is a Gram-positive bacterium that can cause various infections. The Galleria mellonella has been used as a preliminary test for infection model. The study aimed to evaluate the effectiveness of G. mellonella as a microbiome model and compare the efficacy of vancomycin and antimicrobial activity of Nigella sativa (NS) on the gut flora. Methods G. mellonella larvae were subjected to metagenomic analysis. The larvae's guts were collected, homogenized in phosphate-buffered saline (PBS), and the gut contents isolated for bacterial DNA extraction. Larvae were assigned into the following groups: negative control (PBS only); positive control (MRSA only); vancomycin treated group; NS oil treated group and combination (vancomycin and NS oil) treated group. Larvae were cultured, inoculated with S. aureus, and treated with vancomycin and NS oil. Larval activity, cocoon formation, growth, melanization, and survival were monitored. The toxicity of vancomycin and NS oil was tested, and S. aureus burden and natural microbiota were determined. Hemocyte density was measured. Statistical analysis was conducted using R. Results Enterococcus related species dominated approximately 90 % of the gastrointestinal tract of the larvae. The survival rate following treatment was 85 % with vancomycin, 64 % with NS oil, and 73 % with a combination of both. The count of Enterococcus Colony Forming Units (CFUs) was significantly lower in the vancomycin treatment group (8.14E+04) compared to those treated with NS oil (1.97E+06) and the combination treatment (8.95E+05). Furthermore, the S. aureus burden was found to be lower in the NS oil (1.04E+06) and combination treatment groups (9.02E+05) compared to the vancomycin treatment group (3.38E+06). Hemocyte densities were significantly higher in the NS oil (8.29E+06) and combination treatment groups (8.18E+06) compared to the vancomycin treatment group (4.89E+06). Conclusions The study supported the use of G. mellonella model as a preliminary test to assess the effect of different antimicrobials against S. aureus and gut microbiota. NS oil showed more selectivity against S. aureus and protectiveness for the natural Enterococcus gut flora.
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Affiliation(s)
- Faris S. Alnezary
- Department of Pharmacy Practice, College of Pharmacy, Taibah University, Madinah 41477, Saudi Arabia
| | - Masaad Saeed Almutairi
- Department of Pharmacy Practice, College of Pharmacy, Qassim University, Qassim 51452, Saudi Arabia
| | - Abdullah A. Alhifany
- Department of Clinical Pharmacy, College of Pharmacy, Umm Al-Qura University, Makkah, Saudi Arabia
| | - Thamer A. Almangour
- Department of Clinical Pharmacy, College of Pharmacy, King Saud University, P.O. Box 2457, Riyadh 11451, Saudi Arabia
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12
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Sultan M, Arya R, Chaurasia AK, Kim KK. Sensor histidine kinases kdpD and aauS regulate biofilm and virulence in Pseudomonas aeruginosa PA14. Front Cell Infect Microbiol 2023; 13:1270667. [PMID: 37881370 PMCID: PMC10595159 DOI: 10.3389/fcimb.2023.1270667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 09/25/2023] [Indexed: 10/27/2023] Open
Abstract
Pseudomonas aeruginosa is a multidrug-resistant opportunistic human pathogen that utilizes two-component systems (TCSs) to sense pathophysiological signals and coordinate virulence. P. aeruginosa contains 64 sensor histidine kinases (HKs) and 72 response regulators (RRs) that play important roles in metabolism, bacterial physiology, and virulence. However, the role of some TCSs in virulence remains uncharacterized. In this study, we evaluated the virulence potential of some uncharacterized sensor HK and RR knockouts in P. aeruginosa using a Galleria mellonella infection model. Furthermore, we demonstrated that KdpD and AauS HKs regulate virulence by affecting P. aeruginosa biofilm formation and motility. Both ΔkdpD and ΔaauS showed reduced biofilm and motility which were confirmed by restored phenotypes upon complementation. Moreover, ΔkdpD and ΔaauS exhibited increased survival of HeLa cells and G. mellonella during in vivo infection. Altered expression of the transcriptional regulators anR and lasR, along with the virulence genes lasA, pelA, cupA, pqsA, pqsB, pqsC, and pqsD in the mutant strains elucidated the mechanism by which ΔkdpD and ΔaauS affect virulence. These findings confirm that kdpD and aauS play important roles in P. aeruginosa pathogenesis by regulating biofilm formation and motility.
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Affiliation(s)
- Maria Sultan
- Department of Precision Medicine, Graduate School of Basic Medical Science, Institute for Antimicrobial Resistance Research and Therapeutics, Sungkyunkwan University School of Medicine, Suwon, Republic of Korea
| | - Rekha Arya
- Department of Precision Medicine, Graduate School of Basic Medical Science, Institute for Antimicrobial Resistance Research and Therapeutics, Sungkyunkwan University School of Medicine, Suwon, Republic of Korea
- Department of Orthopedic Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Akhilesh Kumar Chaurasia
- Department of Precision Medicine, Graduate School of Basic Medical Science, Institute for Antimicrobial Resistance Research and Therapeutics, Sungkyunkwan University School of Medicine, Suwon, Republic of Korea
| | - Kyeong Kyu Kim
- Department of Precision Medicine, Graduate School of Basic Medical Science, Institute for Antimicrobial Resistance Research and Therapeutics, Sungkyunkwan University School of Medicine, Suwon, Republic of Korea
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Räz AK, Andreoni F, Boumasmoud M, Bergada-Pijuan J, Schweizer TA, Mairpady Shambat S, Hasse B, Zinkernagel AS, Brugger SD. Limited Adaptation of Staphylococcus aureus during Transition from Colonization to Invasive Infection. Microbiol Spectr 2023; 11:e0259021. [PMID: 37341598 PMCID: PMC10433843 DOI: 10.1128/spectrum.02590-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 05/24/2023] [Indexed: 06/22/2023] Open
Abstract
Staphylococcus aureus carriage is a risk factor for invasive infections. Unique genetic elements favoring the transition from colonizing to invasive phenotype have not yet been identified, and phenotypic adaptation traits are understudied. We therefore assessed phenotypic and genotypic profiles of 11 S. aureus isolate pairs sampled from colonized patients simultaneously suffering from invasive S. aureus infections. Ten out of 11 isolate pairs displayed the same spa and multilocus sequence type, suggesting colonization as an origin for the invasive infection. Systematic analysis of colonizing and invasive isolate pairs showed similar adherence, hemolysis, reproductive fitness properties, antibiotic tolerance, and virulence in a Galleria mellonella infection model, as well as minimal genetic differences. Our results provide insights into the similar phenotypes associated with limited adaptation between colonizing and invasive isolates. Disruption of the physical barriers of mucosa or skin was identified in the majority of patients, further emphasizing colonization as a major risk factor for invasive disease. IMPORTANCE S. aureus is a major pathogen of humans, causing a wide range of diseases. The difficulty to develop a vaccine and antibiotic treatment failure warrant the exploration of novel treatment strategies. Asymptomatic colonization of the human nasal passages is a major risk factor for invasive disease, and decolonization procedures have been effective in preventing invasive infections. However, the transition of S. aureus from a benign colonizer of the nasal passages to a major pathogen is not well understood, and both host and bacterial properties have been discussed as being relevant for this behavioral change. We conducted a thorough investigation of patient-derived strain pairs reflecting colonizing and invasive isolates in a given patient. Although we identified limited genetic adaptation in certain strains, as well as slight differences in adherence capacity among colonizing and invasive isolates, our work suggests that barrier breaches are a key event in the disease continuum of S. aureus.
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Affiliation(s)
- Anna K. Räz
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Federica Andreoni
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Mathilde Boumasmoud
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Judith Bergada-Pijuan
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Tiziano A. Schweizer
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Srikanth Mairpady Shambat
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Barbara Hasse
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Annelies S. Zinkernagel
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Silvio D. Brugger
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
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Bugyna L, Kendra S, Bujdáková H. Galleria mellonella-A Model for the Study of aPDT-Prospects and Drawbacks. Microorganisms 2023; 11:1455. [PMID: 37374956 PMCID: PMC10301295 DOI: 10.3390/microorganisms11061455] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 05/29/2023] [Accepted: 05/30/2023] [Indexed: 06/29/2023] Open
Abstract
Galleria mellonella is a promising in vivo model insect used for microbiological, medical, and pharmacological research. It provides a platform for testing the biocompatibility of various compounds and the kinetics of survival after an infection followed by subsequent treatment, and for the evaluation of various parameters during treatment, including the host-pathogen interaction. There are some similarities in the development of pathologies with mammals. However, a limitation is the lack of adaptive immune response. Antimicrobial photodynamic therapy (aPDT) is an alternative approach for combating microbial infections, including biofilm-associated ones. aPDT is effective against Gram-positive and Gram-negative bacteria, viruses, fungi, and parasites, regardless of whether they are resistant to conventional treatment. The main idea of this comprehensive review was to collect information on the use of G. mellonella in aPDT. It provides a collection of references published in the last 10 years from this area of research, complemented by some practical experiences of the authors of this review. Additionally, the review summarizes in brief information on the G. mellonella model, its advantages and methods used in the processing of material from these larvae, as well as basic knowledge of the principles of aPDT.
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Affiliation(s)
| | | | - Helena Bujdáková
- Faculty of Natural Sciences, Department of Microbiology and Virology, Comenius University in Bratislava, Ilkovicova 6, 84215 Bratislava, Slovakia; (L.B.); (S.K.)
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Knockout of ykcB, a Putative Glycosyltransferase, Leads to Reduced Susceptibility to Vancomycin in Bacillus subtilis. J Bacteriol 2022; 204:e0038722. [PMID: 36409129 PMCID: PMC9765085 DOI: 10.1128/jb.00387-22] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Vancomycin resistance of Gram-positive bacteria poses a serious health concern around the world. In this study, we searched for vancomycin-tolerant mutants from a gene deletion library of a model Gram-positive bacterium, Bacillus subtilis, to elucidate the mechanism of vancomycin resistance. We found that knockout of ykcB, a glycosyltransferase that is expected to utilize C55-P-glucose to glycosylate cell surface components, caused reduced susceptibility to vancomycin in B. subtilis. Knockout of ykcB altered the susceptibility to multiple antibiotics, including sensitization to β-lactams and increased the pathogenicity to silkworms. Furthermore, the ykcB-knockout mutant had (i) a decreased amount of lipoteichoic acid, (ii) decreased biofilm formation, and (iii) an increased content of diglucosyl diacylglycerol, a glycolipid that shares a precursor with C55-P-glucose. These phenotypes and vancomycin tolerance were abolished by knockout of ykcC, a gene in the same operon with ykcB probably involved in C55-P-glucose synthesis. Overexpression of ykcC enhanced vancomycin tolerance in both the parent strain and the ykcB-knockout mutant. These findings suggest that ykcB deficiency induces structural changes of cell surface molecules depending on the ykcC function, leading to reduced susceptibility to vancomycin, decreased biofilm formation, and increased pathogenicity to silkworms. IMPORTANCE Although vancomycin is effective against Gram-positive bacteria, vancomycin-resistant bacteria are a major public health concern. While the vancomycin-resistance mechanisms of clinically important bacteria such as Staphylococcus aureus, Enterococcus faecium, and Streptococcus pneumoniae are well studied, they remain unclear in other Gram-positive bacteria. In the present study, we searched for vancomycin-tolerant mutants from a gene deletion library of a model Gram-positive bacterium, Bacillus subtilis, and found that knockout of a putative glycosyltransferase, ykcB, caused vancomycin tolerance in B. subtilis. Notably, unlike the previously reported vancomycin-resistant bacterial strains, ykcB-deficient B. subtilis exhibited increased virulence while maintaining its growth rate. Our results broaden the fundamental understanding of vancomycin-resistance mechanisms in Gram-positive bacteria.
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Engineering Antibacterial Activities and Biocompatibility of Hyperbranched Lysine-based Random Copolymers. CHINESE JOURNAL OF POLYMER SCIENCE 2022. [DOI: 10.1007/s10118-022-2859-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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17
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Rao Y, Peng H, Shang W, Hu Z, Yang Y, Tan L, Li M, Zhou R, Rao X. A vancomycin resistance-associated WalK(S221P) mutation attenuates the virulence of vancomycin-intermediate Staphylococcus aureus. J Adv Res 2022; 40:167-178. [PMID: 36100324 PMCID: PMC9481939 DOI: 10.1016/j.jare.2021.11.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 11/22/2021] [Accepted: 11/23/2021] [Indexed: 11/25/2022] Open
Abstract
INTRODUCTION Vancomycin-intermediate Staphylococcus aureus (VISA) is typically associated with a decline in virulence. We previously reported a WalK(S221P) mutation that plays an important role in mediating vancomycin resistance in VISA XN108. Whether this mutation is implicated in bacterial virulence remains unknown. OBJECTIVES This study aimed to investigate the effect of WalK(S221P) mutation on the virulence of VISA and the underlying mechanism of this effect. METHODS The influence of WalK(S221P) mutation on VISA virulence and its underlying mechanism were explored using animal models, RNA-seq analysis, RT-qPCR, hemolytic assay, slide coagulase test, Western blot, β-galactosidase assay, and electrophoresis mobility shift assay (EMSA). RESULTS Compared with XN108, WalK(S221P)-reverted strain XN108-R exacerbated cutaneous infections with increased lesion size and extensive inflammatory infiltration in mouse models. The bacterial loads of S. aureus XN108-R in murine kidney increased compared with those of XN108. RNA-seq analysis showed upregulation of a set of virulence genes in XN108-R, which exhibited greater hemolytic and stronger coagulase activities compared with XN108. Introduction of WalK(S221P) to methicillin-resistant S. aureus USA300 and methicillin-susceptible strain Newman increased the vancomycin resistance of the mutants, which exhibited reduced hemolytic activities and decreased expression levels of many virulence factors compared with their progenitors. WalK(S221P) mutation weakened agr promoter-controlled β-galactosidase activity. EMSA results showed that WalK-phosphorylated WalR could directly bind to the agr promoter region, whereas WalK(S221P)-activated WalR reduced binding to the target promoter. Inactivation of agr in S. aureus did not affect their vancomycin susceptibility but mitigated the virulence alterations caused by WalK(S221P) mutation. CONCLUSION The results of our study indicate that WalK(S221P) mutation can enhance vancomycin resistance in S. aureus of diverse genetic backgrounds. WalK(S221P)- bearing S. aureus strains exhibit reduced virulence. WalK(S221P) mutation may directly impair the activation of the agr system by WalR, thereby decreasing the expression of virulence factors in VISA.
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Affiliation(s)
- Yifan Rao
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University (Third Military Medical University), Chongqing 400038, China; Department of Emergency Medicine, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing 400037, China
| | - Huagang Peng
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University (Third Military Medical University), Chongqing 400038, China
| | - Weilong Shang
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University (Third Military Medical University), Chongqing 400038, China
| | - Zhen Hu
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University (Third Military Medical University), Chongqing 400038, China
| | - Yi Yang
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University (Third Military Medical University), Chongqing 400038, China
| | - Li Tan
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University (Third Military Medical University), Chongqing 400038, China
| | - Ming Li
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University (Third Military Medical University), Chongqing 400038, China.
| | - Renjie Zhou
- Department of Emergency Medicine, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing 400037, China.
| | - Xiancai Rao
- Department of Microbiology, College of Basic Medical Sciences, Army Medical University (Third Military Medical University), Chongqing 400038, China.
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Methods for Using the Galleria mellonella Invertebrate Model to Probe Enterococcus faecalis Pathogenicity. Methods Mol Biol 2022; 2427:177-183. [PMID: 35619034 DOI: 10.1007/978-1-0716-1971-1_15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The Enterococci, mainly Enterococcus faecalis and E. faecium, are ubiquitous members of the human gastrointestinal tract consortia but also a leading cause of opportunistic infections. The global rise in human-associated enterococcal infections, often caused by multidrug resistant strains, highlights an urgent need to identify the bacterial factors contributing to its pathogenicity such that new therapies can be devised. The use of the Galleria mellonella (greater wax moth) larvae, commonly known as wax worm, as a model to study host-pathogen interactions has allowed the identification and characterization of numerous bacterial factors that contribute to disease in humans, serving both as an alternative and complementary approach to mammalian models. Here, we describe the methods for using G. mellonella to characterize the virulence factors of E. faecalis.
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Baseri N, Najar-Peerayeh S, Bakhshi B, Campanile F. Phenotypic and genotypic changes of Staphylococcus aureus in the presence of the inappropriate concentration of chlorhexidine gluconate. BMC Microbiol 2022; 22:100. [PMID: 35418037 PMCID: PMC9006606 DOI: 10.1186/s12866-022-02522-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Accepted: 04/06/2022] [Indexed: 11/10/2022] Open
Abstract
Background Chlorhexidine gluconate (CHG) is a disinfectant agent with different applications in health care. Improper use of CHG causes antimicrobial resistance in bacteria as a public health threat. Since Staphylococcus aureus is a common bacteria, it is expected usually exposed to CHG in the hospital and community. The present study aimed to correlate the phenotypic and genotypic changes in a S. aureus strain upon serial adaptation with supra-inhibitory CHG concentration for 50 days. Results After in vitro serial culture of 5 × 105 CFU/ml of a clinical vancomycin-susceptible S. aureus strain (VAN-S) into brain heart infusion (BHI) broth containing CHG 1/4, 1/2, 1, and 2 × minimal inhibitory concentration (MIC) values of VAN-S in 37 °C during 50 days, we isolated a S. aureus strain (CHGVan-I) with a ≥ twofold decrease in susceptibility to CHG and vancomycin. CHG-induced CHGVan-I strain was considered as a vancomycin-intermediate S. aureus (VISA) strain with a VAN MIC of 4 μg/ml using the broth macro dilution method. However, reduced resistance was observed to tetracycline family antibiotics (doxycycline and tetracycline) using a modified Kirby-Bauer disk diffusion test. Moreover, a remarkable reduction was detected in growth rate, hemolysis activity (the lysis of human red blood cells by alpha-hemolysin), and colony pigmentation (on BHI agar plates). Biofilm formation (using the Microtiter plate method and crystal violet staining) was significantly increased upon CHG treatment. Adaptive changes in the expression of a set of common genes related to the development of VISA phenotype (graTSR, vraTSR, walKR, agr RNAIII, sceD, pbpB, and fmtA) were analyzed by Reverse Transcription quantitative PCR (RT-qPCR) experiment. Significant changes in vraTSR, agr RNAIII, sceD, and pbpB expression were observed. However, gene sequencing of the two-component system vraTSR using the Sanger sequencing method did not detect any non-synonymous substitution in CHGVan-I compared to wild-type. The clonality of VAN-S and CHGVan-I strains was verified using the pulsed-field gel electrophoresis (PFGE) method. Conclusions The importance of the present study should be stated in new detected mechanisms underlying VISA development. We found a link between the improper CHX use and the development of phenotypic and genotypic features, typical of VISA clinical isolates, in a CHG-induced strain. Since disruption of the cell wall biosynthesis occurs in VISA isolates, our CHG-induced VISA strain proved new insights into the role of CHG in the stimulation of the S. aureus cell wall.
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Affiliation(s)
- Neda Baseri
- Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Shahin Najar-Peerayeh
- Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Bita Bakhshi
- Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
| | - Floriana Campanile
- Department of Biomedical and Biotechnological Sciences (BIOMETEC), Medical Molecular Microbiology and Antibiotic Resistance Laboratory (MMARLab), University of Catania, Catania, Italy
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RNase R, a New Virulence Determinant of Streptococcus pneumoniae. Microorganisms 2022; 10:microorganisms10020317. [PMID: 35208772 PMCID: PMC8875335 DOI: 10.3390/microorganisms10020317] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 01/20/2022] [Accepted: 01/25/2022] [Indexed: 11/30/2022] Open
Abstract
Pneumococcal infections have increasingly high mortality rates despite the availability of vaccines and antibiotics. Therefore, the identification of new virulence determinants and the understanding of the molecular mechanisms behind pathogenesis have become of paramount importance in the search of new targets for drug development. The exoribonuclease RNase R has been involved in virulence in a growing number of pathogens. In this work, we used Galleria mellonella as an infection model to demonstrate that the presence of RNase R increases the pneumococcus virulence. Larvae infected with the RNase R mutant show an increased expression level of antimicrobial peptides. Furthermore, they have a lower bacterial load in the hemolymph in the later stages of infection, leading to a higher survival rate of the larvae. Interestingly, pneumococci expressing RNase R show a sudden drop in bacterial numbers immediately after infection, resembling the eclipse phase observed after intravenous inoculation in mice. Concomitantly, we observed a lower number of mutant bacteria inside larval hemocytes and a higher susceptibility to oxidative stress when compared to the wild type. Together, our results indicate that RNase R is involved in the ability of pneumococci to evade the host immune response, probably by interfering with internalization and/or replication inside the larval hemocytes.
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21
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Kim Y, Kim S, Park J, Lee H. Clinical Response and Hospital Costs of Therapeutic Drug Monitoring for Vancomycin in Elderly Patients. J Pers Med 2022; 12:jpm12020163. [PMID: 35207653 PMCID: PMC8875716 DOI: 10.3390/jpm12020163] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 01/01/2022] [Accepted: 01/03/2022] [Indexed: 12/04/2022] Open
Abstract
Cost-effectiveness analysis has been widely used to assess and compare the costs and benefits of a clinical service. The cost-effectiveness of vancomycin therapeutic drug monitoring (TDM) has not been studied in the elderly, who are susceptible to vancomycin-induced adverse effects. This study was performed to evaluate if vancomycin TDM is cost-effective in elderly patients in the Republic of Korea. Using the electronic medical records at a tertiary university hospital, we performed a retrospective observational study to evaluate the cost-effectiveness of vancomycin TDM in 850 elderly patients who underwent vancomycin TDM with an appropriate, recommended dosing regimen and 1094 elderly patients who did not. Cost-effectiveness variables such as clinical outcomes and medical expenses were evaluated using univariate and multivariate analyses. The TDM group spent significantly less than the non-TDM group per patient for total medical expenses (by USD 841.40) and medication expenses (by USD 16.70). However, no significant difference was noted between the TDM and non-TDM groups in clinical outcomes such as microbiological cure, prevention of nephrotoxicity, or reduced mortality, irrespective of admission to the intensive care unit. Vancomycin TDM in elderly patients was associated with economic benefits, but not with better clinical outcomes.
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Affiliation(s)
- Yun Kim
- Department of Clinical Pharmacology and Therapeutics, Seoul National University College of Medicine and Hospital, Seoul 03080, Korea; (Y.K.); (J.P.)
- Hanyang Medicine-Engineering-Bio Collaborative & Comprehensive Center for Drug Development (MEBC), Hanyang University, Seoul 04763, Korea
| | - Soohyun Kim
- Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul National University, Seoul 03080, Korea;
- Center for Convergence Approaches in Drug Development, Graduate School of Convergence Science and Technology, Seoul National University, Seoul 03087, Korea
| | - Jinsook Park
- Department of Clinical Pharmacology and Therapeutics, Seoul National University College of Medicine and Hospital, Seoul 03080, Korea; (Y.K.); (J.P.)
| | - Howard Lee
- Department of Clinical Pharmacology and Therapeutics, Seoul National University College of Medicine and Hospital, Seoul 03080, Korea; (Y.K.); (J.P.)
- Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul National University, Seoul 03080, Korea;
- Center for Convergence Approaches in Drug Development, Graduate School of Convergence Science and Technology, Seoul National University, Seoul 03087, Korea
- Advanced Institute of Convergence Technology, Suwon-si 16229, Korea
- Correspondence: ; Tel.: +82-2-3668-7602
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22
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Surgical mesh coatings for infection control and temperature sensing: An in-vitro investigation. OPENNANO 2021. [DOI: 10.1016/j.onano.2021.100032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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23
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Dijokaite A, Humbert MV, Borkowski E, La Ragione RM, Christodoulides M. Establishing an invertebrate Galleria mellonella greater wax moth larval model of Neisseria gonorrhoeae infection. Virulence 2021; 12:1900-1920. [PMID: 34304706 PMCID: PMC8312596 DOI: 10.1080/21505594.2021.1950269] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 06/21/2021] [Accepted: 06/26/2021] [Indexed: 11/24/2022] Open
Abstract
Neisseria gonorrhoeae (gonococcus) causes the human sexually transmitted disease gonorrhea. Studying gonococcal pathogenesis and developing new vaccines and therapies to combat the increasing prevalence of multi-antibiotic resistant bacteria has made use of many ex vivo models based on human cells and tissues, and in vivo vertebrate models, for example, rodent, pig and human. The focus of the current study was to examine the utility of the invertebrate greater wax moth Galleria mellonella as an in vivo model of gonococcal infection. We observed that a threshold of ~106 - 107 gonococci/larva was required to kill >50% of larvae (P < 0.05), and increased toxicity correlated with reduced health index scores and pronounced histopathological changes such as increases in the total lesion grade, melanized nodules, hemocyte reaction, and multifocal adipose body degeneration. Larval death was independent of the expression of pilus or Opa protein or LOS sialylation within a single gonococcal species studied, but the model could demonstrate relative toxicity of different isolates. N. meningitidis, N. lacatamica and gonococci all killed larvae equally, but were significantly less toxic (P > 0.05) than Pseudomonas aeruginosa. Larvae primed with nontoxic doses of gonococci were more susceptible to subsequent challenge with homologous and heterologous bacteria, and larval survival was significantly reduced (P < 0.05) in infected larvae after depletion of their hemocytes with clodronate-liposomes. The model was used to test the anti-gonococcal properties of antibiotics and novel antimicrobials. Ceftriaxone (P < 0.05) protected larvae from infection with different gonococcal isolates, but not azithromycin or monocaprin or ligand-coated silver nanoclusters (P > 0.05).
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Affiliation(s)
- Aiste Dijokaite
- Neisseria Research Group, Molecular Microbiology, Academic School of Clinical and Experimental Sciences, University of Southampton Faculty of Medicine, Southampton, UK
| | - Maria Victoria Humbert
- Neisseria Research Group, Molecular Microbiology, Academic School of Clinical and Experimental Sciences, University of Southampton Faculty of Medicine, Southampton, UK
| | - Emma Borkowski
- Department of Pathology and Infectious Diseases, School of Veterinary Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
| | - Roberto M La Ragione
- Department of Pathology and Infectious Diseases, School of Veterinary Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
| | - Myron Christodoulides
- Neisseria Research Group, Molecular Microbiology, Academic School of Clinical and Experimental Sciences, University of Southampton Faculty of Medicine, Southampton, UK
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24
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Derakhshan S, Navidinia M, Haghi F. Antibiotic susceptibility of human-associated Staphylococcus aureus and its relation to agr typing, virulence genes, and biofilm formation. BMC Infect Dis 2021; 21:627. [PMID: 34210263 PMCID: PMC8247160 DOI: 10.1186/s12879-021-06307-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 06/10/2021] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND AND OBJECTIVE Carriage of virulence factors confers some evolutionary benefit to bacteria, which favors the resistant strains. We aimed to analyze whether antibiotic susceptibility of Staphylococcus aureus strains is affected by agr typing, biofilm formation ability, and virulence profiles. METHODS A total of 123 S. aureus clinical isolates were subjected to antimicrobial susceptibility testing by disk diffusion method, biofilm formation by microtiter plate method, as well as polymerase chain reaction screening to identify virulence genes and the accessory gene regulator (agr) types I-IV. A P value < 0.05 was considered significant. RESULTS The most prevalent virulence gene was staphyloxanthin crtN, followed by hemolysin genes, capsular cap8H, toxic shock toxin tst, and enterotoxin sea, respectively. Resistant isolates were more commonly found in the agr-negative group than in the agr-positive group. Isolates of agr type III were more virulent than agr I isolates. Strong biofilm producers showed more antibiotic susceptibility and carried more virulence genes than non-strong biofilm producers. Associations were found between the presence of virulence genes and susceptibility to antibiotics. Carriage of the virulence genes and agr was higher in the inpatients; while, resistance and strong biofilms were more prevalent in the outpatients. CONCLUSION These findings indicated the presence of several virulence factors, biofilm production capacity, agr types and resistance to antibiotics in clinical S. aureus isolates. Considering the importance of S. aureus for human medicine, an understanding of virulence and resistance relationships would help to reduce the impact of S. aureus infections.
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Affiliation(s)
- Safoura Derakhshan
- Liver and Digestive Research Center, Research Institute for Health Development, Kurdistan University of Medical Sciences, Sanandaj, Iran.
| | - Masoumeh Navidinia
- School of Allied Medical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Fakhri Haghi
- Department of Microbiology and Immunology, Faculty of Medical Sciences, Zanjan University of Medical Sciences, Zanjan, Iran
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25
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Henly EL, Norris K, Rawson K, Zoulias N, Jaques L, Chirila PG, Parkin KL, Kadirvel M, Whiteoak C, Lacey MM, Smith TJ, Forbes S. Impact of long-term quorum sensing inhibition on uropathogenic Escherichia coli. J Antimicrob Chemother 2021; 76:909-919. [PMID: 33406232 DOI: 10.1093/jac/dkaa517] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 11/16/2020] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Quorum sensing is an extracellular bacterial communication system used in the density-dependent regulation of gene expression and development of biofilms. Biofilm formation has been implicated in the establishment of catheter-associated urinary tract infections and therefore quorum sensing inhibitors (QSIs) have been suggested as anti-biofilm catheter coating agents. The long-term effects of QSIs in uropathogens is, however, not clearly understood. OBJECTIVES We evaluated the effects of repeated exposure to the QSIs cinnamaldehyde, (Z)-4-bromo-5(bromomethylene)-2(5H)-furanone-C30 (furanone-C30) and 4-fluoro-5-hydroxypentane-2,3-dione (F-DPD) on antimicrobial susceptibility, biofilm formation and relative pathogenicity in eight uropathogenic Escherichia coli (UPEC) isolates. METHODS MICs, MBCs and minimum biofilm eradication concentrations and antibiotic susceptibility were determined. Biofilm formation was quantified using crystal violet. Relative pathogenicity was assessed in a Galleria mellonella model. To correlate changes in phenotype to gene expression, transcriptomic profiles were created through RNA sequencing and variant analysis of genomes was performed in strain EC958. RESULTS Cinnamaldehyde and furanone-C30 led to increases in susceptibility in planktonic and biofilm-associated UPEC. Relative pathogenicity increased after cinnamaldehyde exposure (4/8 isolates), decreased after furanone-C30 exposure (6/8 isolates) and varied after F-DPD exposure (one increased and one decreased). A total of 9/96 cases of putative antibiotic cross-resistance were generated. Exposure to cinnamaldehyde or F-DPD reduced expression of genes associated with locomotion, whilst cinnamaldehyde caused an increase in genes encoding fimbrial and afimbrial-like adhesins. Furanone-C30 caused a reduction in genes involved in cellular biosynthetic processes, likely though impaired ribonucleoprotein assembly. CONCLUSIONS The multiple phenotypic adaptations induced during QSI exposure in UPEC should be considered when selecting an anti-infective catheter coating agent.
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Affiliation(s)
- E L Henly
- Biomolecular Sciences Research Centre, Sheffield Hallam University, Sheffield, UK
| | - K Norris
- Biomolecular Sciences Research Centre, Sheffield Hallam University, Sheffield, UK
| | - K Rawson
- Biomolecular Sciences Research Centre, Sheffield Hallam University, Sheffield, UK
| | - N Zoulias
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, UK
| | - L Jaques
- Biomolecular Sciences Research Centre, Sheffield Hallam University, Sheffield, UK
| | - P G Chirila
- Biomolecular Sciences Research Centre, Sheffield Hallam University, Sheffield, UK
| | - K L Parkin
- Biomolecular Sciences Research Centre, Sheffield Hallam University, Sheffield, UK
| | - M Kadirvel
- Manchester Pharmacy School, University of Manchester, Manchester, UK
| | - C Whiteoak
- Biomolecular Sciences Research Centre, Sheffield Hallam University, Sheffield, UK
| | - M M Lacey
- Biomolecular Sciences Research Centre, Sheffield Hallam University, Sheffield, UK
| | - T J Smith
- Biomolecular Sciences Research Centre, Sheffield Hallam University, Sheffield, UK
| | - S Forbes
- Biomolecular Sciences Research Centre, Sheffield Hallam University, Sheffield, UK
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Yu J, Rao L, Zhan L, Wang B, Zhan Q, Xu Y, Zhao H, Wang X, Zhou Y, Guo Y, Wu X, Song Z, Yu F. The small molecule ZY-214-4 may reduce the virulence of Staphylococcus aureus by inhibiting pigment production. BMC Microbiol 2021; 21:67. [PMID: 33639851 PMCID: PMC7916275 DOI: 10.1186/s12866-021-02113-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 02/02/2021] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND In recent years, clinical Staphylococcus aureus isolates have become highly resistant to antibiotics, which has raised concerns about the ability to control infections by these organisms. The aim of this study was to clarify the effect of a new small molecule, ZY-214-4 (C19H11BrNO4), on S. aureus pigment production. RESULTS At the concentration of 4 μg/mL, ZY-214-4 exerted a significant inhibitory effect on S. aureus pigment synthesis, without affecting its growth or inducing a toxic effect on the silkworm. An oxidant sensitivity test and a whole-blood killing test indicated that the S. aureus survival rate decreased significantly with ZY-214-4 treatment. Additionally, ZY-214-4 administration significantly reduced the expression of a pigment synthesis-related gene (crtM) and the superoxide dismutase genes (sodA) as determined by real-time quantitative polymerase chain reaction (RT-qPCR) analysis. ZY-214-4 treatment also improved the survival rate of S. aureus-infected silkworm larvae. CONCLUSIONS The small molecule ZY-214-4 has potential for the prevention of S. aureus infections by reducing the virulence associated with this bacterium.
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Affiliation(s)
- Jingyi Yu
- Department of Laboratory Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, China
| | - Lulin Rao
- Department of Laboratory Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, China
| | - Lingling Zhan
- Department of Laboratory Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, China
| | - Bingjie Wang
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, 200082, China
| | - Qing Zhan
- Nanchang University, Nanchang, 330027, China
| | - Yanlei Xu
- Nanchang University, Nanchang, 330027, China
| | - Huilin Zhao
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, 200082, China
| | - Xinyi Wang
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, 200082, China
| | - Yan Zhou
- School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, 325000, China
| | - Yinjuan Guo
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, 200082, China
- Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, 200082, China
| | - Xiaocui Wu
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, 200082, China
- Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, 200082, China
| | - Zengqiang Song
- School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, 325000, China.
| | - Fangyou Yu
- Department of Clinical Laboratory, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, 200082, China.
- Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, 200082, China.
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Association between high vancomycin minimum inhibitory concentration and clinical outcomes in patients with methicillin-resistant Staphylococcus aureus bacteremia: a meta-analysis. Infection 2021; 49:803-811. [PMID: 33394368 DOI: 10.1007/s15010-020-01568-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 12/14/2020] [Indexed: 12/26/2022]
Abstract
PURPOSE To assess the relationship between high vancomycin minimum inhibitory concentrations (MIC), in patients with methicillin-resistant Staphylococcus aureus bacteremia (MRSAB), and both mortality and complicated bacteremia. METHODS Embase, Medline, EBM, Scopus and Web of Science were searched for studies published from January 1st 2014 to February 29th 2020. "High" vancomycin MIC cut off was defined as ≥ 1.5 mg/L. Three referees independently reviewed studies that compared outcomes in patients with MRSAB stratified by vancomycin MIC. Subgroup analyses were performed for rates of mortality and complicated bacteremia. RESULTS A total of 13 studies with 2089 patients were included. Overall, mortality was 27.7% and 23.3% in the high and low vancomycin MIC group, respectively. No significant difference was found between vancomycin MIC groups for overall mortality, in-hospital mortality, late mortality, persistent bacteremia, severe sepsis or septic shock, acute renal failure, septic emboli or endocarditis, and osteomyelitis or septic arthritis. Early mortality was significantly associated with low vancomycin MIC. Mortality in studies using broth microdilution method (BMD) and need for mechanical ventilation were significantly associated with high vancomycin MIC. CONCLUSION Overall mortality and complicated bacteremia were not significantly associated with high vancomycin MICs in a patient with MRSAB. Randomized controlled trials to assess the utility of vancomycin MIC values in predicting mortality and other adverse clinical outcomes are warranted.
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28
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Lee SO, Lee S, Lee JE, Song KH, Kang CK, Wi YM, San-Juan R, López-Cortés LE, Lacoma A, Prat C, Jang HC, Kim ES, Kim HB, Lee SH. Dysfunctional accessory gene regulator (agr) as a prognostic factor in invasive Staphylococcus aureus infection: a systematic review and meta-analysis. Sci Rep 2020; 10:20697. [PMID: 33244173 PMCID: PMC7691521 DOI: 10.1038/s41598-020-77729-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 11/17/2020] [Indexed: 12/14/2022] Open
Abstract
The accessory gene regulator (agr) locus of Staphylococcus aureus is a quorum-sensing virulence regulator. Although there are many studies concerning the effect of dysfunctional agr on the outcomes of S. aureus infection, there is no systematic review to date. We systematically searched for clinical studies reporting outcomes of invasive S. aureus infections and the proportion of dysfunctional agr among their causative strains, and we performed a meta-analysis to obtain estimates of the odds of outcomes of invasive S. aureus infection with dysfunctional versus functional agr. Of 289 articles identified by our research strategy, 20 studies were meta-analysed for crude analysis of the impact of dysfunctional agr on outcomes of invasive S. aureus infection. Dysfunctional agr was generally associated with unfavourable outcomes (OR 1.32, 95% CI 1.05–1.66), and the impact of dysfunctional agr on outcome was more prominent in invasive methicillin-resistant S. aureus (MRSA) infections (OR 1.54, CI 1.20–1.97). Nine studies were meta-analysed for the impact of dysfunctional agr on the 30-day mortality of invasive S. aureus infection. Invasive MRSA infection with dysfunctional agr exhibited higher 30-day mortality (OR 1.40, CI 1.03–1.90) than that with functional agr. On the other hand, invasive MSSA infection with dysfunctional agr exhibited lower 30-day mortality (OR 0.51, CI 0.27–0.95). In the post hoc subgroup analysis by the site of MRSA infection, dysfunctional agr was associated with higher 30-day mortality in MRSA pneumonia (OR 2.48, CI 1.17–5.25). The effect of dysfunctional agr on the outcome of invasive S. aureus infection may vary depending on various conditions, such as oxacillin susceptibility and the site of infection. Dysfunctional agr was generally associated with unfavourable clinical outcomes and its effect was prominent in MRSA and pneumonia. Dysfunctional agr may be applicable for outcome prediction in cases of invasive MRSA infection with hardly eradicable foci such as pneumonia.
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Affiliation(s)
- Soon Ok Lee
- Department of Internal Medicine, Pusan National University School of Medicine and Medical Research Institute, Pusan National University Hospital, 179 Gudeok-ro, Seo-gu, Busan, 49241, Republic of Korea
| | - Shinwon Lee
- Department of Internal Medicine, Pusan National University School of Medicine and Medical Research Institute, Pusan National University Hospital, 179 Gudeok-ro, Seo-gu, Busan, 49241, Republic of Korea.
| | - Jeong Eun Lee
- Department of Internal Medicine, Pusan National University School of Medicine and Medical Research Institute, Pusan National University Hospital, 179 Gudeok-ro, Seo-gu, Busan, 49241, Republic of Korea
| | - Kyoung-Ho Song
- Department of Internal Medicine, Seoul National University College of Medicine and Seoul National University Bundang Hospital, Seongnam, Republic of Korea
| | - Chang Kyung Kang
- Department of Internal Medicine, Seoul National University College of Medicine and Seoul National University Hospital, Seoul, Republic of Korea
| | - Yu Mi Wi
- Division of Infectious Diseases, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, Republic of Korea
| | - Rafael San-Juan
- Unit of Infectious Diseases, University Hospital 12 de Octubre, Instituto de Investigación Hospital "12 de Octubre" (i+12), Universidad Complutense, Avenida de Córdoba, s/n, Madrid, Spain
| | - Luis E López-Cortés
- Unidad Clínica de Enfermedades Infecciosas, Microbiología y Medicina Preventiva, Hospital Universitario Virgen Macarena/Departamento de Medicina, Universidad de Sevilla/Instituto de Biomedicina de Sevilla, Sevilla, Spain
| | - Alicia Lacoma
- Microbiology Department, Hospital Universitari Germans Trias i Pujol, Institut d' Investigació Germans Trias i Pujol, CIBER Enfermedades Respiratorias (CIBERES), Universitat Autònoma de Barcelona, Badalona, Spain
| | - Cristina Prat
- Microbiology Department, Hospital Universitari Germans Trias i Pujol, Institut d' Investigació Germans Trias i Pujol, CIBER Enfermedades Respiratorias (CIBERES), Universitat Autònoma de Barcelona, Badalona, Spain.,Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Hee-Chang Jang
- Department of Infectious Diseases, Chonnam National University Medical School, Gwang-ju, Republic of Korea
| | - Eu Suk Kim
- Department of Internal Medicine, Seoul National University College of Medicine and Seoul National University Bundang Hospital, Seongnam, Republic of Korea
| | - Hong Bin Kim
- Department of Internal Medicine, Seoul National University College of Medicine and Seoul National University Bundang Hospital, Seongnam, Republic of Korea
| | - Sun Hee Lee
- Department of Internal Medicine, Pusan National University School of Medicine and Medical Research Institute, Pusan National University Hospital, 179 Gudeok-ro, Seo-gu, Busan, 49241, Republic of Korea
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Jin Y, Yu X, Zhang S, Kong X, Chen W, Luo Q, Zheng B, Xiao Y. Comparative Analysis of Virulence and Toxin Expression of Vancomycin-Intermediate and Vancomycin-Sensitive Staphylococcus aureus Strains. Front Microbiol 2020; 11:596942. [PMID: 33193280 PMCID: PMC7661696 DOI: 10.3389/fmicb.2020.596942] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Accepted: 10/12/2020] [Indexed: 01/19/2023] Open
Abstract
Previous studies on vancomycin-intermediate Staphylococcus aureus (VISA) have mainly focused on drug resistance, the evolution of differences in virulence between VISA and vancomycin-sensitive S. aureus (VSSA) requires further investigation. To address this issue, in this study, we compared the virulence and toxin profiles of pair groups of VISA and VSSA strains, including a series of vancomycin-resistant induced S. aureus strains—SA0534, SA0534-V8, and SA0534-V16. We established a mouse skin infection model to evaluate the invasive capacity of VISA strains, and found that although mice infected with VISA had smaller-sized abscesses than those infected with VSSA, the abscesses persisted for a longer period (up to 9 days). Infection with VISA strains was associated with a lower mortality rate in Galleria mellonella larvae compared to infection with VSSA strains (≥ 40% vs. ≤ 3% survival at 28 h). Additionally, VISA were more effective in colonizing the nasal passage of mice than VSSA, and in vitro experiments showed that while VISA strains were less virulent they showed enhanced intracellular survival compared to VSSA strains. RNA sequencing of VISA strains revealed significant differences in the expression levels of the agr, hla, cap, spa, clfB, and sbi genes and suggested that platelet activation is only weakly induced by VISA. Collectively, our findings indicate that VISA is less virulent than VSSA but has a greater capacity to colonize human hosts and evade destruction by the host innate immune system, resulting in persistent and chronic S. aureus infection.
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Affiliation(s)
- Ye Jin
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Xiao Yu
- Department of Respiratory and Critical Care Medicine, First Hospital of Shanxi Medical University, Taiyuan, China
| | - Shuntian Zhang
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Xiaoyang Kong
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Weiwei Chen
- Department of Laboratory Medicine, College of Medicine, Zhejiang University, Hangzhou, China
| | - Qixia Luo
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Beiwen Zheng
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Yonghong Xiao
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
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30
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Kaito C, Murakami K, Imai L, Furuta K. Animal infection models using non-mammals. Microbiol Immunol 2020; 64:585-592. [PMID: 32757288 PMCID: PMC7590188 DOI: 10.1111/1348-0421.12834] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 07/17/2020] [Accepted: 07/27/2020] [Indexed: 12/31/2022]
Abstract
The use of non-human animal models for infection experiments is important for investigating the infectious processes of human pathogenic bacteria at the molecular level. Mammals, such as mice and rabbits, are also utilized as animal infection models, but large numbers of animals are needed for these experiments, which is costly, and fraught with ethical issues. Various non-mammalian animal infection models have been used to investigate the molecular mechanisms of various human pathogenic bacteria, including Staphylococcus aureus, Streptococcus pyogenes, and Pseudomonas aeruginosa. This review discusses the desirable characteristics of non-mammalian infection models and describes recent non-mammalian infection models that utilize Caenorhabditis elegans, silkworm, fruit fly, zebrafish, two-spotted cricket, hornworm, and waxworm.
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Affiliation(s)
- Chikara Kaito
- Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Kanade Murakami
- Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Lina Imai
- Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Kazuyuki Furuta
- Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama, Japan
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Zhao WB, Du MR, Liu KK, Zhou R, Ma RN, Jiao Z, Zhao Q, Shan CX. Hydrophilic ZnO Nanoparticles@Calcium Alginate Composite for Water Purification. ACS APPLIED MATERIALS & INTERFACES 2020; 12:13305-13315. [PMID: 32092266 DOI: 10.1021/acsami.9b23458] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Herein, hydrophilic ZnO nanoparticles@calcium alginate composite has been prepared by embedding hydrophilic ZnO nanoparticles (NPs) into calcium alginate. The hydrophilic ZnO NPs within the composites can act as a killer of bacteria, while calcium alginate can remove the organic impurities due to its adsorption capacity, thus realizing the purification of water via sterilization and removal of organics. A water purifier based on the composite has been demonstrated, the aerobic bacterial counts of the contaminated water can be decreased from 2240 to 9 cfu mL-1, and the turbidity of the water is decreased to 0.51 NTU, which is below the maximum permissible of Guidelines for Drinking-water Quality designed by the World Health Organization. Sterilization mechanism studies show that the ZnO NPs can cause excessive oxidative stress in cells, inducing bacteria to produce large amounts of intracellular reactive oxygen species (ROS), which leads to the apoptosis of the bacteria.
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Affiliation(s)
- Wen-Bo Zhao
- Henan Key Laboratory of Diamond Optoelectronic Materials and Devices, Key Laboratory of Materials Physics, Ministry of Education, School of Physics and Microelectronics, Zhengzhou University, Zhengzhou 450052, China
| | - Meng-Ru Du
- Henan Key Laboratory of Ion-beam Bioengineering, School of Agricultural Science, Zhengzhou University, Zhengzhou 450052, China
| | - Kai-Kai Liu
- Henan Key Laboratory of Diamond Optoelectronic Materials and Devices, Key Laboratory of Materials Physics, Ministry of Education, School of Physics and Microelectronics, Zhengzhou University, Zhengzhou 450052, China
| | - Rui Zhou
- Henan Key Laboratory of Diamond Optoelectronic Materials and Devices, Key Laboratory of Materials Physics, Ministry of Education, School of Physics and Microelectronics, Zhengzhou University, Zhengzhou 450052, China
| | - Ruo-Nan Ma
- Henan Key Laboratory of Ion-beam Bioengineering, School of Agricultural Science, Zhengzhou University, Zhengzhou 450052, China
| | - Zhen Jiao
- Henan Key Laboratory of Ion-beam Bioengineering, School of Agricultural Science, Zhengzhou University, Zhengzhou 450052, China
| | - Qi Zhao
- Henan Key Laboratory of Diamond Optoelectronic Materials and Devices, Key Laboratory of Materials Physics, Ministry of Education, School of Physics and Microelectronics, Zhengzhou University, Zhengzhou 450052, China
| | - Chong-Xin Shan
- Henan Key Laboratory of Diamond Optoelectronic Materials and Devices, Key Laboratory of Materials Physics, Ministry of Education, School of Physics and Microelectronics, Zhengzhou University, Zhengzhou 450052, China
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Sáez C, Sarriá C, Vilacosta I, Olmos C, López J, García-Granja PE, Fernández C, de las Cuevas C, Reyes G, Domínguez L, San Román JA. "A contemporary description of staphylococcus aureus prosthetic valve endocarditis. Differences according to the time elapsed from surgery". Medicine (Baltimore) 2019; 98:e16903. [PMID: 31464922 PMCID: PMC6736462 DOI: 10.1097/md.0000000000016903] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 07/08/2019] [Accepted: 07/26/2019] [Indexed: 11/26/2022] Open
Abstract
Staphylococcus aureus prosthetic valve endocarditis (SAPVE) has a poor prognosis. There are no large series that accurately describe this entity.This is a retrospective observational study on a prospective cohort from 3 Spanish reference hospitals for cardiac surgery, including 78 definitive episodes of left SAPVE between 1996 and 2016.Fifty percent had a Charlson Index score >5; 53% were health care-related. Twenty percent did not present fever. Complications at diagnosis included: severe heart failure (HF, 29%), septic shock (SS, 17.9%), central nervous system abnormalities (19%), septic metastasis (4%). Hemorrhagic stroke was not higher in anticoagulated patients. Twenty-seven percent were methicilin-resistant SA (MRSA). Fifteen of 31 had positive valve culture; it was related to surgery within first 24 hours. At diagnosis, 69% had vegetation (>10 mm in 75%), 21.8% perianular extension, and 20% prosthetic dehiscence. Forty-eight percent had persistent bacteremia, related to nonsurgical treatment. Perianular extension progressed in 18%. Surgery was performed in 35 episodes (12 with stroke). Eleven uncomplicated episodes were managed with medical therapy, 8 survived. In-hospital mortality was 55%, higher in episodes with hemorrhagic stroke (77.8% vs 52.2%, odds ratio 3.2 [0.62-16.55]). Early SAPVE was nosocomial (92%), presented as severe HF (54%), patients were diagnosed and operated on early, 38% died. In intermediate SAPVE (9 weeks-1 year) diagnosis was delayed (24%), patients presented with constitutional syndrome (18%), renal failure (41%), and underwent surgery >72 hours after indication; 53% died. Late SAPVE (>1 year) was related with health care, diagnosis delay, and 60% of deceases.Left SAPVE frequently affected patients with comorbidity and health care contact. Complications at diagnosis and absence of fever were frequent. Presence of MRSA was high. Positive valve culture was related to early surgery. Paravalvular extension was frequent; vegetations were large, but its absence at diagnosis was common. Some uncomplicated SAPVE episodes were safety treated with medical therapy. Surgery was feasible in patients with stroke. Mortality was high. There were differences in some clinical characteristics and in evolution according to the time elapsed from valve replacement. Prognosis was better in early SAPVE.
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Affiliation(s)
- Carmen Sáez
- Department of Medicine-Infectious diseases, Instituto de Investigación Sanitaria, Hospital Universitario de la Princesa, Universidad Autónoma de Madrid, Spain
| | - Cristina Sarriá
- Department of Medicine-Infectious diseases, Instituto de Investigación Sanitaria, Hospital Universitario de la Princesa, Universidad Autónoma de Madrid, Spain
| | - Isidre Vilacosta
- Instituto Cardiovascular. Hospital Universitario Clínico San Carlos, Madrid, Spain
| | - Carmen Olmos
- Instituto Cardiovascular. Hospital Universitario Clínico San Carlos, Madrid, Spain
| | - Javier López
- Department of Cardiology, Instituto de Ciencias del Corazón (ICICOR), CIBERCV, Hospital Clínico Universitario de Valladolid, Valladolid, Spain
| | - Pablo Elpidio García-Granja
- Department of Cardiology, Instituto de Ciencias del Corazón (ICICOR), CIBERCV, Hospital Clínico Universitario de Valladolid, Valladolid, Spain
| | - Cristina Fernández
- Instituto Cardiovascular. Hospital Universitario Clínico San Carlos, Madrid, Spain
| | - Carmen de las Cuevas
- Department of Microbiology, Hospital Universitario de la Princesa, Instituto de Investigación Sanitaria, Universidad Autónoma de Madrid, Spain
| | - Guillermo Reyes
- Department of Cardiac Surgery, Hospital Universitario de la Princesa, Instituto de Investigación Sanitaria, Universidad Autónoma de Madrid, Spain
| | - Lourdes Domínguez
- Department of Cardiology, Hospital Universitario de la Princesa, Instituto de Investigación Sanitaria, Universidad Autónoma de Madrid, Spain
| | - Jose Alberto San Román
- Department of Cardiology, Instituto de Ciencias del Corazón (ICICOR), CIBERCV, Hospital Clínico Universitario de Valladolid, Valladolid, Spain
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Tan XE, Neoh HM, Cui L, Hiramatsu K, Jamal R. Oxidative stress resistance and fitness-compensatory response in vancomycin-intermediate Staphylococcus aureus (VISA). Can J Microbiol 2019; 65:623-628. [DOI: 10.1139/cjm-2019-0048] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In this study, vancomycin-intermediate Staphylococcus aureus (VISA) cells carrying vraS and (or) graR mutations were shown to be more resistant to oxidative stress. Caenorhabditis elegans infected with these strains in turn demonstrated lower survival. Altered regulation in oxidative stress response and virulence appear to be physiological adaptations associated with the VISA phenotype in the Mu50 lineage.
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Affiliation(s)
- Xin-Ee Tan
- UKM Medical Molecular Biology Institute (UMBI), Universiti Kebangsaan Malaysia, Malaysia
| | - Hui-min Neoh
- UKM Medical Molecular Biology Institute (UMBI), Universiti Kebangsaan Malaysia, Malaysia
- Department of Bacteriology, School of Medicine, Juntendo University, Japan
| | - Longzhu Cui
- Division of Bacteriology, Department of Infection and Immunity, School of Medicine, Jichi Medical University, Japan
| | - Keiichi Hiramatsu
- Department of Bacteriology, School of Medicine, Juntendo University, Japan
| | - Rahman Jamal
- UKM Medical Molecular Biology Institute (UMBI), Universiti Kebangsaan Malaysia, Malaysia
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A plasmid-encoded peptide from Staphylococcus aureus induces anti-myeloperoxidase nephritogenic autoimmunity. Nat Commun 2019; 10:3392. [PMID: 31358739 PMCID: PMC6662820 DOI: 10.1038/s41467-019-11255-0] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2018] [Accepted: 06/26/2019] [Indexed: 12/21/2022] Open
Abstract
Autoreactivity to myeloperoxidase (MPO) causes anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV), with rapidly progressive glomerulonephritis. Here, we show that a Staphylococcus aureus peptide, homologous to an immunodominant MPO T-cell epitope (MPO409–428), can induce anti-MPO autoimmunity. The peptide (6PGD391–410) is part of a plasmid-encoded 6-phosphogluconate dehydrogenase found in some S. aureus strains. It induces anti-MPO T-cell autoimmunity and MPO-ANCA in mice, whereas related sequences do not. Mice immunized with 6PGD391–410, or with S. aureus containing a plasmid expressing 6PGD391–410, develop glomerulonephritis when MPO is deposited in glomeruli. The peptide induces anti-MPO autoreactivity in the context of three MHC class II allomorphs. Furthermore, we show that 6PGD391–410 is immunogenic in humans, as healthy human and AAV patient sera contain anti-6PGD and anti-6PGD391–410 antibodies. Therefore, our results support the idea that bacterial plasmids might have a function in autoimmune disease. Autoreactivity to myeloperoxidase (MPO) causes autoimmune vasculitis and severe glomerulonephritis. Here, Ooi et al. show that a Staphylococcus aureus plasmid encodes a peptide that is homologous to an immunodominant MPO epitope and induces anti-MPO autoimmunity and glomerulonephritis in mice.
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Zhao X, Palma Medina LM, Stobernack T, Glasner C, de Jong A, Utari P, Setroikromo R, Quax WJ, Otto A, Becher D, Buist G, van Dijl JM. Exoproteome Heterogeneity among Closely Related Staphylococcus aureus t437 Isolates and Possible Implications for Virulence. J Proteome Res 2019; 18:2859-2874. [PMID: 31119940 PMCID: PMC6617432 DOI: 10.1021/acs.jproteome.9b00179] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Staphylococcus aureus with spa-type t437 has been identified as a predominant community-associated methicillin-resistant S. aureus clone from Asia, which is also encountered in Europe. Molecular typing has previously shown that t437 isolates are highly similar regardless of geographical regions or host environments. The present study was aimed at assessing to what extent this high similarity is actually reflected in the production of secreted virulence factors. We therefore profiled the extracellular proteome, representing the main reservoir of virulence factors, of 20 representative clinical isolates by mass spectrometry. The results show that these isolates can be divided into three groups and nine subgroups based on exoproteome abundance signatures. This implies that S. aureus t437 isolates show substantial exoproteome heterogeneity. Nonetheless, 30 highly conserved extracellular proteins, of which about 50% have a predicted role in pathogenesis, were dominantly identified. To approximate the virulence of the 20 investigated isolates, we employed infection models based on Galleria mellonella and HeLa cells. The results show that the grouping of clinical isolates based on their exoproteome profile can be related to virulence. We consider this outcome important as our approach provides a tool to pinpoint differences in virulence among seemingly highly similar clinical isolates of S. aureus.
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Affiliation(s)
- Xin Zhao
- University of Groningen , University Medical Center Groningen, Department of Medical Microbiology , Hanzeplein 1 , P.O. Box 30001, 9700 RB Groningen , The Netherlands
| | - Laura M Palma Medina
- University of Groningen , University Medical Center Groningen, Department of Medical Microbiology , Hanzeplein 1 , P.O. Box 30001, 9700 RB Groningen , The Netherlands
| | - Tim Stobernack
- University of Groningen , University Medical Center Groningen, Department of Medical Microbiology , Hanzeplein 1 , P.O. Box 30001, 9700 RB Groningen , The Netherlands
| | - Corinna Glasner
- University of Groningen , University Medical Center Groningen, Department of Medical Microbiology , Hanzeplein 1 , P.O. Box 30001, 9700 RB Groningen , The Netherlands
| | - Anne de Jong
- University of Groningen , Groningen Biomolecular Sciences and Biotechnology Institute, Department of Molecular Genetics , 9747 AG Groningen , The Netherlands
| | - Putri Utari
- University of Groningen , Groningen Research Institute of Pharmacy, Department of Chemical and Pharmaceutical Biology , A. Deusinglaan 1 , 9713 AV Groningen , The Netherlands
| | - Rita Setroikromo
- University of Groningen , Groningen Research Institute of Pharmacy, Department of Chemical and Pharmaceutical Biology , A. Deusinglaan 1 , 9713 AV Groningen , The Netherlands
| | - Wim J Quax
- University of Groningen , Groningen Research Institute of Pharmacy, Department of Chemical and Pharmaceutical Biology , A. Deusinglaan 1 , 9713 AV Groningen , The Netherlands
| | - Andreas Otto
- Institut für Mikrobiologie , University of Greifswald , Felix-Hausdorff-Str. 8 , 17475 Greifswald , Germany
| | - Dörte Becher
- Institut für Mikrobiologie , University of Greifswald , Felix-Hausdorff-Str. 8 , 17475 Greifswald , Germany
| | - Girbe Buist
- University of Groningen , University Medical Center Groningen, Department of Medical Microbiology , Hanzeplein 1 , P.O. Box 30001, 9700 RB Groningen , The Netherlands
| | - Jan Maarten van Dijl
- University of Groningen , University Medical Center Groningen, Department of Medical Microbiology , Hanzeplein 1 , P.O. Box 30001, 9700 RB Groningen , The Netherlands
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Sheehan G, Dixon A, Kavanagh K. Utilization of Galleria mellonella larvae to characterize the development of Staphylococcus aureus infection. MICROBIOLOGY-SGM 2019; 165:863-875. [PMID: 31107207 DOI: 10.1099/mic.0.000813] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Staphylococcus aureus is a human opportunistic pathogen that causes a wide range of superficial and systemic infections in susceptible patients. Here we describe how an inoculum of S. aureus activates the cellular and humoral response of Galleria mellonella larvae while growing and disseminating throughout the host, forming nodules and ultimately killing the host. An inoculum of S. aureus (2×106 larva- 1 ) decreased larval viability at 24 (80±5.77 %), 48 (55.93±5.55 %) and 72 h (10.23±2.97 %) and was accompanied by significant proliferation and dissemination of S. aureus between 6 and 48 h and the formation of nodules in the host. The hemocyte (immune cell) densities increased between 4 and 24 h and hemocytes isolated from larvae after 24 h exposure to heat-killed S. aureus (2×106 larva- 1 ) showed altered killing kinetics as compared to those from control larvae. Alterations in the humoral immune response of larvae 6 and 24 h post-infection were also determined by quantitative shotgun proteomics. The proteome of 6 h-infected larvae was enriched for antimicrobial proteins, proteins of the prophenoloxidase cascade and a range of peptidoglycan recognition proteins. By 24 h there was a significant increase in the abundance of a range of antimicrobial peptides with anti-staphylococcal activity and proteins associated with nodule formation. The results presented here indicate how S. aureus interacts with the larval immune response, induces the expression of a variety of immune-related peptides and also forms nodules which are a hallmark of soft tissue infections during human infection.
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Affiliation(s)
- Gerard Sheehan
- Department of Biology, Maynooth University, Maynooth, Co. Kildare, Ireland
| | - Amy Dixon
- Department of Biology, Maynooth University, Maynooth, Co. Kildare, Ireland
| | - Kevin Kavanagh
- Department of Biology, Maynooth University, Maynooth, Co. Kildare, Ireland
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Brignoli T, Manetti AGO, Rosini R, Haag AF, Scarlato V, Bagnoli F, Delany I. Absence of Protein A Expression Is Associated With Higher Capsule Production in Staphylococcal Isolates. Front Microbiol 2019; 10:863. [PMID: 31133995 PMCID: PMC6523524 DOI: 10.3389/fmicb.2019.00863] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 04/04/2019] [Indexed: 12/19/2022] Open
Abstract
Staphylococcus aureus is a major human pathogen, and a leading cause of soft tissue and blood stream infections. One of the causes of its success as a pathogen is the peculiar array of immune evasion factors through which the bacterium avoids host defenses, where the staphylococcal protein A (SpA) plays a major role thanks to its IgG binding activities. Moreover, SpA has recently been proposed as a promising vaccine antigen. In this study, we evaluated the expression of SpA in a collection of staphylococcal strains, about 7% of which did not express SpA (SpA- strains), despite the presence of the gene. By a comparative genomic analysis, we identified that a mutation in the spa 5′ UTR sequence affecting the RBS is responsible for the loss of SpA in a subset of SpA- strains. Using a high-throughput qRT-PCR approach on a selected panel of virulence-related genes, we identified that the SpA- phenotype is associated with lower spa transcript levels and increased expression and production of capsule as well as other changes in the transcription of several key virulence factors. Our data suggest that the SpA- phenotype has occurred in geographically distinct strains through different molecular mechanisms including both mutation, leading likely to translation alterations, and transcriptional deregulation. Furthermore, we provide evidence that SpA- strains are highly susceptible to phagocytic uptake mediated by anti-capsule antibodies. These data suggest that S. aureus may alter its virulence factor expression pattern as an adaptation to the host or environment. Vaccination strategies targeting both SpA and capsule could therefore result in broader coverage against staphylococcal isolates than SpA alone.
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Affiliation(s)
- Tarcisio Brignoli
- GSK Vaccines, Siena, Italy.,Department of Pharmacy and Biotechnology (FaBiT), University of Bologna, Bologna, Italy
| | | | | | - Andreas F Haag
- GSK Vaccines, Siena, Italy.,Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - Vincenzo Scarlato
- Department of Pharmacy and Biotechnology (FaBiT), University of Bologna, Bologna, Italy
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Subramanian D, Natarajan J. RNA-seq analysis reveals resistome genes and signalling pathway associated with vancomycin-intermediate Staphylococcus aureus. Indian J Med Microbiol 2019; 37:173-185. [PMID: 31745016 DOI: 10.4103/ijmm.ijmm_18_311] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Context Vancomycin-intermediate Staphylococcus aureus remains one of the most prevalent multidrug-resistant pathogens causing healthcare infections that are difficult to treat. Aims This study uses a comprehensive computational analysis to systematically investigate various gene expression profiles of resistant and sensitive S. aureus strains on exposure to antibiotics. Settings and Design The transcriptional changes leading to the development of multiple antibiotic resistance were examined by an integrative analysis of nine differential expression experiments under selected conditions of vancomycin-intermediate and -sensitive strains for four different antibiotics using publicly available RNA-Seq datasets. Materials and Methods For each antibiotic, three experimental conditions for expression analysis were selected to identify those genes that are particularly involved in the development of resistance. The results were further scrutinised to generate a resistome that can be analysed for their role in the development or adaptation to antibiotic resistance. Results The 99 genes in the resistome are then compiled to create a multiple drug resistome of 25 known and novel genes identified to play a part in antibiotic resistance. The inclusion of agr genes and associated virulence factors in the identified resistome supports the role of agr quorum sensing system in multiple drug resistance. In addition, enrichment analysis also identified the kyoto encyclopedia of genes and genomes (KEGG) pathways - quorum sensing and two-component system pathways - in the resistome gene set. Conclusion Further studies on understanding the role of the identified molecular targets such as SAA6008_00181, SAA6008_01127, agrA, agrC and coa in adapting to the pressure of antibiotics at sub-inhibitory concentrations can help in learning the molecular mechanisms causing resistance to the pathogens as well as finding other potential therapeutics.
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Affiliation(s)
- Devika Subramanian
- Department of Bioinformatics, Data Mining and Text Mining Laboratory, Bharathiar University, Coimbatore, Tamil Nadu, India
| | - Jeyakumar Natarajan
- Department of Bioinformatics, Data Mining and Text Mining Laboratory, Bharathiar University, Coimbatore, Tamil Nadu, India
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Biocide Exposure Induces Changes in Susceptibility, Pathogenicity, and Biofilm Formation in Uropathogenic Escherichia coli. Antimicrob Agents Chemother 2019; 63:AAC.01892-18. [PMID: 30642923 PMCID: PMC6395906 DOI: 10.1128/aac.01892-18] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 12/23/2018] [Indexed: 12/15/2022] Open
Abstract
Uropathogenic Escherichia coli (UPEC) is a frequent cause of catheter-associated urinary tract infection (CAUTI). Biocides have been incorporated into catheter coatings to inhibit bacterial colonization while, ideally, exhibiting low cytotoxicity and mitigating the selection of resistant bacterial populations. We compared the effects of long-term biocide exposure on susceptibility, biofilm formation, and relative pathogenicity in eight UPEC isolates. MICs, minimum bactericidal concentrations (MBCs), minimum biofilm eradication concentrations (MBECs), and antibiotic susceptibilities were determined before and after long-term exposure to triclosan, polyhexamethylene biguanide (PHMB), benzalkonium chloride (BAC), and silver nitrate. Biofilm formation was quantified using a crystal violet assay, and relative pathogenicity was assessed via a Galleria mellonella waxworm model. Cytotoxicity and the resulting biocompatibility index values were determined by use of an L929 murine fibroblast cell line. Biocide exposure resulted in multiple decreases in biocide susceptibility in planktonic and biofilm-associated UPEC. Triclosan exposure induced the largest frequency and magnitude of susceptibility decreases at the MIC, MBC, and MBEC, which correlated with an increase in biofilm biomass in all isolates. Induction of antibiotic cross-resistance occurred in 6/84 possible combinations of bacteria, biocide, and antibiotic. Relative pathogenicity significantly decreased after triclosan exposure (5/8 isolates), increased after silver nitrate exposure (2/8 isolates), and varied between isolates for PHMB and BAC. The biocompatibility index ranked the antiseptic potential as PHMB > triclosan > BAC > silver nitrate. Biocide exposure in UPEC may lead to reductions in biocide and antibiotic susceptibility, changes in biofilm formation, and alterations in relative pathogenicity. These data indicate the multiple consequences of biocide adaptation that should be considered when selecting an anti-infective catheter-coating agent.
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Lee HS, Lee S, Kim JS, Lee HR, Shin HC, Lee MS, Jin KS, Kim CH, Ku B, Ryu CM, Kim SJ. Structural and Physiological Exploration of Salmonella Typhi YfdX Uncovers Its Dual Function in Bacterial Antibiotic Stress and Virulence. Front Microbiol 2019; 9:3329. [PMID: 30692978 PMCID: PMC6339873 DOI: 10.3389/fmicb.2018.03329] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 12/21/2018] [Indexed: 12/31/2022] Open
Abstract
YfdX is a prokaryotic protein encoded by several pathogenic bacteria including Salmonella enterica serovar Typhi, which causes one of the most fatal infectious diseases, typhoid fever. YfdX is a product of the yfdXWUVE operon and is known to be under the control of EvgA, a regulator protein controlling the expression of several proteins involved in response to environmental stress, in Escherichia coli. Nevertheless, unlike other proteins encoded by the same operon, the structural and physiological aspects of YfdX have been poorly characterized. Here, we identified a previously unknown pH-dependent stoichiometric conversion of S. Typhi YfdX between dimeric and tetrameric states; this conversion was further analyzed via determining its structure by X-ray crystallography at high resolution and by small-angle X-ray scattering in a solution state and via structure-based mutant studies. Biologically, YfdX was proven to be critically involved in Salmonella susceptibility to two β-lactam antibiotics, penicillin G and carbenicillin, as bacterial growth significantly impaired by its deficiency upon treatment with each of the two antibiotics was recovered by chromosomal complementation. Furthermore, by using Galleria mellonella larvae as an in vivo model of Salmonella infection, we demonstrated that Salmonella virulence was remarkably enhanced by YfdX deficiency, which was complemented by a transient expression of the wild-type or dimeric mutant but not by that of the monomeric mutant. The present study work provides direct evidence regarding the participation of YfdX in Salmonella antibiotic susceptibility and in the modulation of bacterial virulence, providing a new insight into this pathogen's strategies for survival and growth.
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Affiliation(s)
- Hye Seon Lee
- Disease Target Structure Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, South Korea
- Department of Biology, Chungnam National University, Daejeon, South Korea
| | - Soohyun Lee
- Infectious Disease Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, South Korea
| | - Jun-Seob Kim
- Infectious Disease Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, South Korea
| | - Hae-Ran Lee
- Infectious Disease Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, South Korea
| | - Ho-Chul Shin
- Disease Target Structure Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, South Korea
| | - Moo-Seung Lee
- Infectious Disease Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, South Korea
| | - Kyeong Sik Jin
- Pohang Accelerator Laboratory, Pohang University of Science and Technology, Pohang, South Korea
| | - Cheol-Hee Kim
- Department of Biology, Chungnam National University, Daejeon, South Korea
| | - Bonsu Ku
- Disease Target Structure Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, South Korea
| | - Choong-Min Ryu
- Infectious Disease Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, South Korea
- Department of Biotechnology, University of Science and Technology KRIBB School, Daejeon, South Korea
| | - Seung Jun Kim
- Disease Target Structure Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, South Korea
- Department of Bioscience, University of Science and Technology KRIBB School, Daejeon, South Korea
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Kim T, Chong YP, Park KH, Bang KM, Park SJ, Kim SH, Jeong JY, Lee SO, Choi SH, Woo JH, Kim YS. Clinical and microbiological factors associated with early patient mortality from methicillin-resistant Staphylococcus aureus bacteremia. Korean J Intern Med 2019; 34:184-194. [PMID: 28859468 PMCID: PMC6325428 DOI: 10.3904/kjim.2016.351] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 02/01/2017] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND/AIMS Methicillin-resistant Staphylococcus aureus bacteremia (MRSAB) is a major bloodstream infection with a high mortality rate. Identification of factors associated with early mortality in MRSAB patients would be useful for predicting prognosis and developing new therapeutic options. METHODS A prospective cohort of MRSAB patients was examined between August 2008 and June 2011. Early and late mortality was defined as death within 2 and 28 days of blood culture, respectively. The clinical and microbiological characteristics in the early and late mortality and survival groups were compared. Risk factors associated with severe sepsis or septic shock were also investigated. RESULTS A total of 385 adult MRSAB patients whose S. aureus isolates were available were enrolled; of these patients, 25 patients (6.5%) and 50 (13%) died early and late, respectively. Compared with both the late-mortality group and the survival group, severe sepsis or septic shock was a statistically significant independent risk factor associated with early mortality. Rapidly or ultimately fatal McCabe and Jackson classification (adjusted odds ratio [aOR], 1.94; 95% confidence interval [CI], 1.25 to 3.02) and pneumonia (aOR, 2.04; 95% CI, 1.03 to 4.02) were independently associated with severe sepsis or septic shock. A vancomycin minimum inhibitory concentration (MIC) ≥ 1.5 μg/mL was associated with a reduced incidence of severe sepsis or septic shock (aOR, 0.53; 95% CI, 0.34 to 0.84). CONCLUSION Severity of illness seems to be the most important risk factor associated with early mortality in MRSAB. Although vancomycin MIC was not independently associated with early mortality, reduced vancomycin susceptibility appears to be linked to reduced disease severity.
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Affiliation(s)
- Tark Kim
- Department of Internal Medicine, Soonchunhyang University Bucheon Hospital, Bucheon, Korea
| | - Yong Pil Chong
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
- Center for Antimicrobial Resistance and Microbial Genetics, University of Ulsan, Seoul, Korea
| | - Ki-Ho Park
- Department of Internal Medicine, Kyung Hee University Hospital, Seoul, Korea
| | - Kyung Mi Bang
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
- Center for Antimicrobial Resistance and Microbial Genetics, University of Ulsan, Seoul, Korea
| | - Su-Jin Park
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
- Center for Antimicrobial Resistance and Microbial Genetics, University of Ulsan, Seoul, Korea
| | - Sung-Han Kim
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Jin-Yong Jeong
- Center for Antimicrobial Resistance and Microbial Genetics, University of Ulsan, Seoul, Korea
- Asan Institute of Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Sang-Oh Lee
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Sang-Ho Choi
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Jun Hee Woo
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Yang Soo Kim
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
- Center for Antimicrobial Resistance and Microbial Genetics, University of Ulsan, Seoul, Korea
- Correspondence to Yang Soo Kim, M.D. Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 05505, Korea Tel: +82-2-3010-3303 Fax: +82-2-3010-6970 E-mail:
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Doyle AA, Krämer T, Kavanagh K, Stephens JC. Cinnamaldehydes: Synthesis, antibacterial evaluation, and the effect of molecular structure on antibacterial activity. RESULTS IN CHEMISTRY 2019. [DOI: 10.1016/j.rechem.2019.100013] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
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Abelenda Alonso G, Corbacho Loarte MD, Ramos RN, Jiménez MC, Ruiz-Capillas JJJ. Staphylococcus aureus bacteremia in a secondary level Spanish hospital: clinical implications of high vancomycin MIC. REVISTA ESPANOLA DE QUIMIOTERAPIA : PUBLICACION OFICIAL DE LA SOCIEDAD ESPANOLA DE QUIMIOTERAPIA 2018; 31:353-362. [PMID: 30014681 PMCID: PMC6172687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
OBJECTIVE One of the most controversial issues in recent years has been the clinical significance of high vancomycin MIC in Staphylococcus aureus bacteremia. The aim of this study was to elucidate the clinical implication that this parameter has in the staphylococcal bacteremia of a second level hospital. METHODS Retrospective descriptive study between January 2014 and September 2016 with 138 records from the blood culture Severo Ochoa University Hospital registry. A total of 98 cases were finally analized. Microbiological analysis of vancomycin MIC was performed using micro dilution technique. RESULTS The mean age was 71.4 ± 12.45 and 63.26% of the patients had a Charlson index ≥6. A 30.61% were carriers of a venous central catheter. The most frequent source was venous central catheter (26.53%). There were 14.24% metastatic events. Global mortality rate at 30 days was 25.51%. The 43.87% of strains had a vancomycin MIC ≥ 2 mg/L. High vancomycin MIC was significantly associated with persistent bacteremia (OR 3.12 [1.13-8.93]), maintaining this statistical significance in methicillin-resistant S. aureus (MRSA) group (p =0.001) but no in methicillin-susceptible S. aureus (MSSA) group (p = 0.13). Persistent bacteremia was also significantly related with permanent catheter carriers (OR 4.18 [1.38-12.61]), peripheric catheter source (OR 5.18 [1.13-8.93]) and metastatic complications (OR 3.82 [1.03- 12.81]). There was no significant association between high vancomycin MIC and mortality. CONCLUSIONS High vancomycin MIC may be useful in daily clinical practice as a marker of poor clearance of S. aureus bacteremia, specially when is due to MRSA strains.
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Affiliation(s)
| | | | - Ruth Núñez Ramos
- Microbiology Clinical Service, Severo Ochoa University Hospital, Leganés, Spain
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Betts JW, Abdul Momin HF, Phee LM, Wareham DW. Comparative activity of tedizolid and glycopeptide combination therapies for the treatment of Staphylococcus aureus infections: an in vitro and in vivo evaluation against strains with reduced susceptibility to glycopeptides. J Med Microbiol 2018; 67:265-271. [DOI: 10.1099/jmm.0.000671] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- J. W. Betts
- Antimicrobial Research Group, Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - H. F. Abdul Momin
- Antimicrobial Research Group, Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - L. M. Phee
- Antimicrobial Research Group, Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
- Division of Infection, Barts Healthcare NHS Trust, London, UK
| | - D. W. Wareham
- Antimicrobial Research Group, Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
- Division of Infection, Barts Healthcare NHS Trust, London, UK
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San-Juan R, Viedma E, Chaves F, Lalueza A, Fortún J, Loza E, Pujol M, Ardanuy C, Morales I, de Cueto M, Resino-Foz E, Morales-Cartagena A, Rico A, Romero MP, Orellana MÁ, López-Medrano F, Fernández-Ruiz M, Aguado JM. High MICs for Vancomycin and Daptomycin and Complicated Catheter-Related Bloodstream Infections with Methicillin-Sensitive Staphylococcus aureus. Emerg Infect Dis 2018; 22:1057-66. [PMID: 27192097 PMCID: PMC4880091 DOI: 10.3201/eid2206.151709] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Patients infected with these bacteria were more likely to have local endovascular complications. We investigated the prognostic role of high MICs for antistaphylococcal agents in patients with methicillin-sensitive Staphylococcus aureus catheter-related bloodstream infection (MSSA CRBSI). We prospectively reviewed 83 episodes from 5 centers in Spain during April 2011–June 2014 that had optimized clinical management and analyzed the relationship between E-test MICs for vancomycin, daptomycin, oxacillin, and linezolid and development of complicated bacteremia by using multivariate analysis. Complicated MSSA CRBSI occurred in 26 (31.3%) patients; MICs for vancomycin and daptomycin were higher in these patients (optimal cutoff values for predictive accuracy = 1.5 μg/mL and 0.5 μg/mL). High MICs for vancomycin (hazard ratio 2.4, 95% CI 1.2–5.5) and daptomycin (hazard ratio 2.4, 95% CI 1.1–5.9) were independent risk factors for development of complicated MSSA CRBSI. Our data suggest that patients with MSSA CRBSI caused by strains that have high MICs for vancomycin or daptomycin are at increased risk for complications.
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Silva LO, Nobre LS, Mil-Homens D, Fialho A, Saraiva LM. Repair of Iron Centers RIC protein contributes to the virulence of Staphylococcus aureus. Virulence 2018; 9:312-317. [PMID: 29020514 PMCID: PMC5955197 DOI: 10.1080/21505594.2017.1389829] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
RICs are a family of bacterial proteins involved in the repair of iron centers containing proteins damaged by the antimicrobial reactive species liberated by the innate immune system of infected hosts. Staphylococcus aureus is a human pathogen with increasing antibiotic resistance that also contains a RIC-like protein. In this work, we show that the survival of S. aureus within macrophages decreases upon inactivation of ric, and that the viability was restored to levels similar to the wild-type strain by reintroduction of ric via in trans complementation. Importantly, in macrophages that do not produce reactive oxygen species, the lower survival of the ric mutant was no longer observed. In lung epithelial cells, the intracellular viability of the S. aureus ric mutant was also shown to be lower than that of the wild-type. The wax moth larvae Galleria mellonella infected with S. aureus ric mutant presented an approximately 2.5-times higher survival when compared to the wild-type strain. Moreover, significantly lower bacterial loads were determined in the larvae hemolymph infected with strains not expressing ric, and complementation assays confirmed that this behavior was related to RIC. Furthermore, expression of the S. aureus ric gene within the larvae increased along the course of infection with a ~20-fold increase after 8 h of infection. Altogether, the data show that RIC is important for the virulence of S. aureus.
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Affiliation(s)
- Liliana O Silva
- a Instituto de Tecnologia Química e Biológica NOVA , Av. da República Oeiras , Portugal
| | - Lígia S Nobre
- a Instituto de Tecnologia Química e Biológica NOVA , Av. da República Oeiras , Portugal
| | - Dalila Mil-Homens
- b Institute for Bioengineering and Biosciences (iBB), Instituto Superior Técnico , Av. Rovisco Pais, 1, Lisboa , Portugal
| | - Arsénio Fialho
- b Institute for Bioengineering and Biosciences (iBB), Instituto Superior Técnico , Av. Rovisco Pais, 1, Lisboa , Portugal
| | - Lígia M Saraiva
- a Instituto de Tecnologia Química e Biológica NOVA , Av. da República Oeiras , Portugal
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Wagley S, Borne R, Harrison J, Baker-Austin C, Ottaviani D, Leoni F, Vuddhakul V, Titball RW. Galleria mellonella as an infection model to investigate virulence of Vibrio parahaemolyticus. Virulence 2018; 9:197-207. [PMID: 28960137 PMCID: PMC5801645 DOI: 10.1080/21505594.2017.1384895] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 09/14/2017] [Accepted: 09/21/2017] [Indexed: 11/24/2022] Open
Abstract
Non-toxigenic V. parahaemolyticus isolates (tdh-/trh-/T3SS2-) have recently been isolated from patients with gastroenteritis. In this study we report that the larvae of the wax moth (Galleria mellonella) are susceptible to infection by toxigenic or non-toxigenic clinical isolates of V. parahaemolyticus. In comparison larvae inoculated with environmental isolates of V. parahaemolyticus did not succumb to disease. Whole genome sequencing of clinical non-toxigenic isolates revealed the presence of a gene encoding a nudix hydrolase, identified as mutT. A V. parahaemolyticus mutT mutant was unable to kill G. mellonella at 24 h post inoculation, indicating a role of this gene in virulence. Our findings show that G. mellonella is a valuable model for investigating screening of possible virulence genes of V. parahaemolyticus and can provide new insights into mechanisms of virulence of atypical non-toxigenic V. parahaemolyticus. These findings will allow improved genetic tests for the identification of pathogenic V. parahaemolyticus to be developed and will have a significant impact for the scientific community.
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Affiliation(s)
- Sariqa Wagley
- Biosciences College of life and Environmental Sciences, University of Exeter, Exeter, Devon, EX4 S4QD, UK
| | | | - Jamie Harrison
- Biosciences College of life and Environmental Sciences, University of Exeter, Exeter, Devon, EX4 S4QD, UK
| | - Craig Baker-Austin
- Centre for Environment, Fisheries, and Aquaculture Science, Weymouth Laboratory, Weymouth, Dorset DT4 8UB UK
| | - Donatella Ottaviani
- Istituto Zooprofilattico Sperimentale dell'Umbria e delle Marche, Laboratorio Nazionale di Riferimento Contaminazioni Batteriologiche dei Molluschi Bivalvi, Ancona, Italy
| | - Francesca Leoni
- Istituto Zooprofilattico Sperimentale dell'Umbria e delle Marche, Laboratorio Nazionale di Riferimento Contaminazioni Batteriologiche dei Molluschi Bivalvi, Ancona, Italy
| | - Varaporn Vuddhakul
- Department of Microbiology, Faculty of Science, Prince of Songkla University, Hat Yai 90110, Thailand
| | - Richard W. Titball
- Biosciences College of life and Environmental Sciences, University of Exeter, Exeter, Devon, EX4 S4QD, UK
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RgpF Is Required for Maintenance of Stress Tolerance and Virulence in Streptococcus mutans. J Bacteriol 2017; 199:JB.00497-17. [PMID: 28924033 DOI: 10.1128/jb.00497-17] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 09/12/2017] [Indexed: 02/01/2023] Open
Abstract
Bacterial cell wall dynamics have been implicated as important determinants of cellular physiology, stress tolerance, and virulence. In Streptococcus mutans, the cell wall is composed primarily of a rhamnose-glucose polysaccharide (RGP) linked to the peptidoglycan. Despite extensive studies describing its formation and composition, the potential roles for RGP in S. mutans biology have not been well investigated. The present study characterizes the impact of RGP disruption as a result of the deletion of rgpF, the gene encoding a rhamnosyltransferase involved in the construction of the core polyrhamnose backbone of RGP. The ΔrgpF mutant strain displayed an overall reduced fitness compared to the wild type, with heightened sensitivities to various stress-inducing culture conditions and an inability to tolerate acid challenge. The loss of rgpF caused a perturbation of membrane-associated functions known to be critical for aciduricity, a hallmark of S. mutans acid tolerance. The proton gradient across the membrane was disrupted, and the ΔrgpF mutant strain was unable to induce activity of the F1Fo ATPase in cultures grown under low-pH conditions. Further, the virulence potential of S. mutans was also drastically reduced following the deletion of rgpF The ΔrgpF mutant strain produced significantly less robust biofilms, indicating an impairment in its ability to adhere to hydroxyapatite surfaces. Additionally, the ΔrgpF mutant lost competitive fitness against oral peroxigenic streptococci, and it displayed significantly attenuated virulence in an in vivoGalleria mellonella infection model. Collectively, these results highlight a critical function of the RGP in the maintenance of overall stress tolerance and virulence traits in S. mutansIMPORTANCE The cell wall of Streptococcus mutans, the bacterium most commonly associated with tooth decay, is abundant in rhamnose-glucose polysaccharides (RGP). While these structures are antigenically distinct to S. mutans, the process by which they are formed and the enzymes leading to their construction are well conserved among streptococci. The present study describes the consequences of the loss of RgpF, a rhamnosyltransferase involved in RGP construction. The deletion of rgpF resulted in severe ablation of the organism's overall fitness, culminating in significantly attenuated virulence. Our data demonstrate an important link between the RGP and cell wall physiology of S. mutans, affecting critical features used by the organism to cause disease and providing a potential novel target for inhibiting the pathogenesis of S. mutans.
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Peng H, Hu Q, Shang W, Yuan J, Zhang X, Liu H, Zheng Y, Hu Z, Yang Y, Tan L, Li S, Hu X, Li M, Rao X. WalK(S221P), a naturally occurring mutation, confers vancomycin resistance in VISA strain XN108. J Antimicrob Chemother 2017; 72:1006-1013. [PMID: 27999059 DOI: 10.1093/jac/dkw518] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Accepted: 11/03/2016] [Indexed: 02/06/2023] Open
Abstract
Objectives Vancomycin-intermediate Staphylococcus aureus (VISA) strains have spread globally. We previously isolated an ST239 VISA (XN108) with a vancomycin MIC of 12 mg/L. The mechanism for XN108 resistance to vancomycin was investigated in this study. Methods Genome comparison was performed to characterize mutations that might contribute to the XN108 resistance phenotype. The novel mutation WalK(S221P) was identified and investigated using allelic replacement experiments. Vancomycin susceptibilities, autolytic activities and morphologies of the strains were examined. Autophosphorylation activities of WalK and the WalK(S221P) mutant were determined in vitro with [λ- 32 P]ATP, and binding activity of WalK(S221P)-activated WalR to the promoter region of its target gene lytM was determined by electrophoretic mobility shift assay. Results Genome comparison revealed three mutations, GraS(T136I), RpoB(H481N) and WalK(S221P), which might be responsible for vancomycin resistance in XN108. The introduction of WalK(S221P) to the vancomycin-susceptible strain N315 increased its vancomycin MIC from 1.5 to 8 mg/L, whereas the allelic replacement of WalK(S221P) with the native N315 WalK allele in XN108 decreased its vancomycin MIC from 12 to 4 mg/L. The VISA strains have thickened cell walls and decreased autolysis, consistent with observed changes in the expression of genes involved in cell wall metabolism and virulence regulation. WalK(S221P) exhibited reduced autophosphorylation, which may lead to reduced phosphorylation of WalR. WalK(S221P)-phosphorylated WalR also exhibited a reduced capacity to bind to the lytM promoter. Conclusions The naturally occurring WalK(S221P) mutation plays a key role in vancomycin resistance in XN108.
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Galleria mellonella is low cost and suitable surrogate host for studying virulence of human pathogenic Vibrio cholerae. Gene 2017; 628:1-7. [PMID: 28698162 DOI: 10.1016/j.gene.2017.07.019] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 07/04/2017] [Accepted: 07/07/2017] [Indexed: 01/05/2023]
Abstract
Vibrio cholerae causes a severe diarrheal disease affecting millions of people worldwide, particularly in low income countries. V. cholerae successfully persist in aquatic environment and its pathogenic strains results in sever enteric disease in humans. This dual life style contributes towards its better survival and persistence inside host gut and in the environment. Alternative animal replacement models are of great value in studying host-pathogen interaction and for quick screening of various pathogenic strains. One such model is Galleria mellonella, a wax moth which has a complex innate immune system and here we investigate its suitability as a model for clinical human isolates of O1 El TOR, Ogawa serotype belonging to two genetically distinct subclades found in Pakistan (PSC-1 and PSC-2). We demonstrate that the PSC-2 strain D59 frequently isolated from inland areas, was more virulent than PSC-1 strain K7 mainly isolated from coastal areas (p=0.0001). In addition, we compared the relative biofilm capability of the representative strains as indicators of their survival and persistence in the environment and K7 showed enhanced biofilm forming capabilities (p=0.004). Finally we present the annotated genomes of the strains D59 and K7, and compared them with the reference strain N16961.
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