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Kavanaugh DW, Sivignon A, Rossez Y, Chouit Z, Chambon C, Béal L, Bonnet M, Hébraud M, Guérardel Y, Nguyen HTT, Barnich N. Biochemical characterization of the Escherichia coli surfaceome: a focus on type I fimbriae and flagella. Front Microbiol 2025; 16:1507286. [PMID: 39973929 PMCID: PMC11839208 DOI: 10.3389/fmicb.2025.1507286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2024] [Accepted: 01/16/2025] [Indexed: 02/21/2025] Open
Abstract
The Escherichia coli surfaceome consists mainly of the large surface organelles expressed by the organism to navigate and interact with the surrounding environment. The current study focuses on type I fimbriae and flagella. These large polymeric surface organelles are composed of hundreds to thousands of subunits, with their large size often preventing them from being studied in their native form. Recent studies are accumulating which demonstrate the glycosylation of surface proteins or virulence factors in pathogens, including E. coli. Using biochemical and glycobiological techniques, including biotin-hydrazide labeling of glycans and chemical and glycosidase treatments, we demonstrate (i) the presence of a well-defined and chemically resistant FimA oligomer in several strains of pathogenic and non-pathogenic E. coli, (ii) the major subunit of type I fimbriae, FimA, in pathogenic and laboratory strains is recognized by concanavalin A, (iii) standard methods to remove N-glycans (PNGase F) or a broad-specificity mannosidase fail to remove the glycan structure, despite the treatments resulting in altered migration in SDS-PAGE, (iv) PNGase F treatment results in a novel 32 kDa band recognized by anti-FliC antiserum. While the exact identity of the glycan(s) and their site of attachment currently elude detection by conventional glycomics/glycoproteomics, the current findings highlight a potential additional layer of complexity of the surface (glyco) proteome of the commensal or adhesive and invasive E. coli strains studied.
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Affiliation(s)
- Devon W. Kavanaugh
- Université Clermont Auvergne, Inserm, INRAE, M2iSH, Université Clermont Auvergne, Clermont–Ferrand, France
| | - Adeline Sivignon
- Université Clermont Auvergne, Inserm, INRAE, M2iSH, Université Clermont Auvergne, Clermont–Ferrand, France
| | - Yannick Rossez
- Unité de Glycobiologie Structurale et Fonctionnelle (UGSF), Université de Lille, Lille, France
| | - Zina Chouit
- Unité de Glycobiologie Structurale et Fonctionnelle (UGSF), Université de Lille, Lille, France
| | - Christophe Chambon
- Plateforme d’Exploration du Métabolisme, Composante Protéomique (PFEMcp), Theix, France
- UR 0370 Qualité des Produits Animaux (QuaPA), INRAE, Theix, France
| | - Louane Béal
- Université Clermont Auvergne, Inserm, INRAE, M2iSH, Université Clermont Auvergne, Clermont–Ferrand, France
| | - Mathilde Bonnet
- Université Clermont Auvergne, Inserm, INRAE, M2iSH, Université Clermont Auvergne, Clermont–Ferrand, France
| | - Michel Hébraud
- Plateforme d’Exploration du Métabolisme, Composante Protéomique (PFEMcp), Theix, France
- Université Clermont Auvergne, INRAE, Microbiologie Environnement Digestif Santé (MEDiS), Clermont–Ferrand, France
| | - Yann Guérardel
- Unité de Glycobiologie Structurale et Fonctionnelle (UGSF), Université de Lille, Lille, France
| | - Hang Thi Thu Nguyen
- Université Clermont Auvergne, Inserm, INRAE, M2iSH, Université Clermont Auvergne, Clermont–Ferrand, France
| | - Nicolas Barnich
- Université Clermont Auvergne, Inserm, INRAE, M2iSH, Université Clermont Auvergne, Clermont–Ferrand, France
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Govindarajan DK, Kandaswamy K. Virulence factors of uropathogens and their role in host pathogen interactions. Cell Surf 2022; 8:100075. [PMID: 35198842 PMCID: PMC8841375 DOI: 10.1016/j.tcsw.2022.100075] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 02/01/2022] [Accepted: 02/06/2022] [Indexed: 12/26/2022] Open
Abstract
Gram-positive and Gram-negative bacterial pathogens are commonly found in Urinary Tract Infection (UTI), particularly infected in females like pregnant women, elder people, sexually active, or individuals prone to other risk factors for UTI. In this article, we review the expression of virulence surface proteins and their interaction with host cells for the most frequently isolated uropathogens: Escherichia coli, Enterococcus faecalis, Proteus mirabilis, Klebsiella pneumoniae, and Staphylococcus saprophyticus. In addition to the host cell interaction, surface protein regulation was also discussed in this article. The surface protein regulation serves as a key tool in differentiating the pathogen isotypes. Furthermore, it might provide insights on novel diagnostic methods to detect uropathogen that are otherwise easily overlooked due to limited culture-based assays. In essence, this review shall provide an in-depth understanding on secretion of virulence factors of various uropathogens and their role in host-pathogen interaction, this knowledge might be useful in the development of therapeutics against uropathogens.
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Affiliation(s)
| | - Kumaravel Kandaswamy
- Corresponding author at: Department of Biotechnology, Kumaraguru College of Technology (KCT), Chinnavedampatti, Coimbatore 641049, Tamil Nadu, India.
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Hatton NE, Baumann CG, Fascione MA. Developments in Mannose-Based Treatments for Uropathogenic Escherichia coli-Induced Urinary Tract Infections. Chembiochem 2021; 22:613-629. [PMID: 32876368 PMCID: PMC7894189 DOI: 10.1002/cbic.202000406] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 08/28/2020] [Indexed: 12/16/2022]
Abstract
During their lifetime almost half of women will experience a symptomatic urinary tract infection (UTI) with a further half experiencing a relapse within six months. Currently UTIs are treated with antibiotics, but increasing antibiotic resistance rates highlight the need for new treatments. Uropathogenic Escherichia coli (UPEC) is responsible for the majority of symptomatic UTI cases and thus has become a key pathological target. Adhesion of type one pilus subunit FimH at the surface of UPEC strains to mannose-saturated oligosaccharides located on the urothelium is critical to pathogenesis. Since the identification of FimH as a therapeutic target in the late 1980s, a substantial body of research has been generated focusing on the development of FimH-targeting mannose-based anti-adhesion therapies. In this review we will discuss the design of different classes of these mannose-based compounds and their utility and potential as UPEC therapeutics.
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Affiliation(s)
- Natasha E. Hatton
- York Structural Biology Lab, Department of ChemistryUniversity of YorkHeslington RoadYorkYO10 5DDUK
| | | | - Martin A. Fascione
- York Structural Biology Lab, Department of ChemistryUniversity of YorkHeslington RoadYorkYO10 5DDUK
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The Nontypeable Haemophilus influenzae Major Adhesin Hia Is a Dual-Function Lectin That Binds to Human-Specific Respiratory Tract Sialic Acid Glycan Receptors. mBio 2020; 11:mBio.02714-20. [PMID: 33144377 PMCID: PMC7642680 DOI: 10.1128/mbio.02714-20] [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] [Indexed: 12/25/2022] Open
Abstract
Host-adapted bacterial pathogens like NTHi have evolved specific mechanisms to colonize their restricted host niche. Relatively few of the adhesins expressed by NTHi have been characterized as regards their binding affinity at the molecular level. In this work, we show that the major NTHi adhesin Hia preferentially binds to Neu5Ac-α2-6-sialyllactosamine, the form of sialic acid expressed in humans. The receptors targeted by Hia in the human airway mirror those targeted by influenza A virus and indicates the broad importance of sialic acid glycans as receptors for microbes that colonize the human airway. NTHi is a human-adapted pathogen that colonizes the human respiratory tract. Strains of NTHi express multiple adhesins; however, there is a unique, mutually exclusive relationship between the major adhesins Hia and HMW1 and HMW2 (HMW1/2). Approximately 25% of NTHi strains express Hia, a phase-variable autotransporter protein that has a critical role in colonization of the host nasopharynx. The remaining 75% of strains express HMW1/2. Previous work has shown that the HMW1 and HMW2 proteins mediate binding to 2-3- and 2-6-linked sialic acid glycans found in the human respiratory tract. Here, we show that the high-affinity binding domain of Hia, binding domain 1 (BD1), is responsible for binding to α2-6-sialyllactosamine (2-6 SLN) glycans. BD1 is highly specific for glycans that incorporate the form of sialic acid expressed by humans, N-acetylneuraminic acid (Neu5Ac). We further show that Hia has lower-affinity binding activity for 2-3-linked sialic acid and that this binding activity is mediated via a distinct domain. Thus, Hia with its dual binding activities functionally mimics the combined activities of the HMW1 and HMW2 adhesins. In addition, we show that Hia has a role in biofilm formation by strains of NTHi that express the adhesin. Knowledge of the binding affinity of this major NTHi adhesin and putative vaccine candidate will direct and inform development of future vaccines and therapeutic strategies for this important pathogen.
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Andrei CC, Moraillon A, Lau S, Felidj N, Yamakawa N, Bouckaert J, Larquet E, Boukherroub R, Ozanam F, Szunerits S, Chantal Gouget-Laemmel A. Rapid and sensitive identification of uropathogenic Escherichia coli using a surface-enhanced-Raman-scattering-based biochip. Talanta 2020; 219:121174. [PMID: 32887096 DOI: 10.1016/j.talanta.2020.121174] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 05/10/2020] [Accepted: 05/14/2020] [Indexed: 02/01/2023]
Abstract
Rapid, selective and sensitive sensing of bacteria remains challenging. We report on a highly sensitive and reproducible surface-enhanced Raman spectroscopy (SERS)-based sensing approach for the detection of uropathogenic Escherichia coli (E. coli) bacteria in urine. The assay is based on the specific capture of the bacteria followed by interaction with cetyltrimethylammonium bromide (CTAB)-stabilised gold nanorods (Au NRS) as SERS markers. High sensitivity up to 10 CFU mL-1 is achieved by optimizing the capture interface based on hydrogenated amorphous silicon a-Si:H thin films. The integration of CH3O-PEG750 onto a-Si:H gives the sensing interface an efficient anti-fouling character, while covalent linkage of antibodies directed against the major type-1 fimbrial pilin FimA of the human pathogen E. coli results in the specific trapping of fimbriated E. coli onto the SERS substrate and their spectral fingerprint identification.
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Affiliation(s)
- Cristina-Cassiana Andrei
- Laboratoire de Physique de La Matière Condensée, Ecole Polytechnique, CNRS, IP Paris, 91128, Palaiseau, France
| | - Anne Moraillon
- Laboratoire de Physique de La Matière Condensée, Ecole Polytechnique, CNRS, IP Paris, 91128, Palaiseau, France
| | - Stephanie Lau
- Université de Paris, ITODYS, CNRS, UMR 7086, 15 Rue J-A de Baïf, F-75013, Paris, France
| | - Nordin Felidj
- Université de Paris, ITODYS, CNRS, UMR 7086, 15 Rue J-A de Baïf, F-75013, Paris, France
| | - Nao Yamakawa
- Unité de Glycobiologie Structurale et Fonctionnelle (UGSF), UMR 8576 of the CNRS and the Univ. Lille, 50 Avenue de Halley, 59658, Villeneuve d'Ascq, France
| | - Julie Bouckaert
- Unité de Glycobiologie Structurale et Fonctionnelle (UGSF), UMR 8576 of the CNRS and the Univ. Lille, 50 Avenue de Halley, 59658, Villeneuve d'Ascq, France
| | - Eric Larquet
- Laboratoire de Physique de La Matière Condensée, Ecole Polytechnique, CNRS, IP Paris, 91128, Palaiseau, France
| | - Rabah Boukherroub
- Univ. Lille, CNRS, Centrale Lille, Univ. Polytechnique Hauts-de-France, UMR 8520-IEMN, F-59000, Lille, France
| | - François Ozanam
- Laboratoire de Physique de La Matière Condensée, Ecole Polytechnique, CNRS, IP Paris, 91128, Palaiseau, France
| | - Sabine Szunerits
- Univ. Lille, CNRS, Centrale Lille, Univ. Polytechnique Hauts-de-France, UMR 8520-IEMN, F-59000, Lille, France.
| | - Anne Chantal Gouget-Laemmel
- Laboratoire de Physique de La Matière Condensée, Ecole Polytechnique, CNRS, IP Paris, 91128, Palaiseau, France.
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6
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Wang P, Meng X, Li J, Chen Y, Zhang D, Zhong H, Xia P, Cui L, Zhu G, Wang H. Transcriptome profiling of avian pathogenic Escherichia coli and the mouse microvascular endothelial cell line bEnd.3 during interaction. PeerJ 2020; 8:e9172. [PMID: 32509459 PMCID: PMC7246031 DOI: 10.7717/peerj.9172] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 04/21/2020] [Indexed: 12/20/2022] Open
Abstract
Background Avian pathogenic Escherichia coli (APEC), an important extraintestinal pathogenic E. coli, causes colibacillosis, an acute and mostly systemic disease involving multiple organ lesions such as meningitis. Meningitis-causing APEC can invade the host central nervous system by crossing the blood–brain barrier (BBB), which is a critical step in the development of meningitis. However, the bacteria-host interaction mechanism in this process remains unclear. Methods In this study, we examined E. coli and bEnd.3 cells transcriptomes during infection and mock infection to investigate the global transcriptional changes in both organisms using RNA sequencing approach. Results When APEC infected the bEnd.3 cells, several significant changes in the expression of genes related to cell junctional complexes, extracellular matrix degradation, actin cytoskeleton rearrangement, immune activation and the inflammatory response in bEnd.3 cells were observed as compared to the mock infection group. Thus, the immune activation of bEnd.3 cells indicated that APEC infection activated host defenses. Furthermore, APEC may exploit cell junction degradation to invade the BBB. In addition, amino acid metabolism and energy metabolism related genes were downregulated and the protein export pathway related genes were upregulated in APEC cultured with bEnd.3 cells, compared to that in control. Thus, APEC may encounter starvation and express virulence factors during incubation with bEnd.3 cells. Conclusion This study provides a comprehensive overview of transcriptomic changes that occur during APEC infection of bEnd.3 cells, and offers insights into the bacterial invasion strategies and the subsequent host defense mechanism.
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Affiliation(s)
- Peili Wang
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, China
| | - Xia Meng
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, China
| | - Jianji Li
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, China
| | - Yanfei Chen
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, China
| | - Dong Zhang
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, China
| | - Haoran Zhong
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, China
| | - Pengpeng Xia
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, China
| | - Luying Cui
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, China
| | - Guoqiang Zhu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, China
| | - Heng Wang
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, China
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Methylation of Salmonella Typhimurium flagella promotes bacterial adhesion and host cell invasion. Nat Commun 2020; 11:2013. [PMID: 32332720 PMCID: PMC7181671 DOI: 10.1038/s41467-020-15738-3] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 03/13/2020] [Indexed: 11/09/2022] Open
Abstract
The long external filament of bacterial flagella is composed of several thousand copies of a single protein, flagellin. Here, we explore the role played by lysine methylation of flagellin in Salmonella, which requires the methylase FliB. We show that both flagellins of Salmonella enterica serovar Typhimurium, FliC and FljB, are methylated at surface-exposed lysine residues by FliB. A Salmonella Typhimurium mutant deficient in flagellin methylation is outcompeted for gut colonization in a gastroenteritis mouse model, and methylation of flagellin promotes bacterial invasion of epithelial cells in vitro. Lysine methylation increases the surface hydrophobicity of flagellin, and enhances flagella-dependent adhesion of Salmonella to phosphatidylcholine vesicles and epithelial cells. Therefore, posttranslational methylation of flagellin facilitates adhesion of Salmonella Typhimurium to hydrophobic host cell surfaces, and contributes to efficient gut colonization and host infection. Flagellin proteins of Salmonella flagella are methylated. Here, the authors show that flagellin methylation facilitates adhesion of Salmonella to hydrophobic host-cell surfaces, and contributes to efficient gut colonization and host infection.
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Zhou M, Duan Q, Li Y, Yang Y, Hardwidge PR, Zhu G. Membrane cholesterol plays an important role in enteropathogen adhesion and the activation of innate immunity via flagellin-TLR5 signaling. Arch Microbiol 2015; 197:797-803. [PMID: 25935453 DOI: 10.1007/s00203-015-1115-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2015] [Revised: 03/17/2015] [Accepted: 04/23/2015] [Indexed: 11/28/2022]
Abstract
Lipid rafts are cholesterol- and sphingolipid-rich ordered microdomains distributed in the plasma membrane that participates in mammalian signal transduction pathways. To determine the role of lipid rafts in mediating interactions between enteropathogens and intestinal epithelial cells, membrane cholesterol was depleted from Caco-2 and IPEC-J2 cells using methyl-β-cyclodextrin. Cholesterol depletion significantly reduced Escherichia coli and Salmonella enteritidis adhesion and invasion into intestinal epithelial cells. Complementation with exogenous cholesterol restored bacterial adhesion to basal levels. We also evaluated the role of lipid rafts in the activation of Toll-like receptor 5 signaling by bacterial flagellin. Depleting membrane cholesterol reduced the ability of purified recombinant E. coli flagellin to activate TLR5 signaling in intestinal cells. These data suggest that both membrane cholesterol and lipid rafts play important roles in enteropathogen adhesion and contribute to the activation of innate immunity via flagellin-TLR5 signaling.
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Affiliation(s)
- Mingxu Zhou
- College of Veterinary Medicine, Yangzhou University, 12 East Wenhui Road, Yangzhou, 225009, China,
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Positively selected FimH residues enhance virulence during urinary tract infection by altering FimH conformation. Proc Natl Acad Sci U S A 2013; 110:15530-7. [PMID: 24003161 DOI: 10.1073/pnas.1315203110] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Chaperone-usher pathway pili are a widespread family of extracellular, Gram-negative bacterial fibers with important roles in bacterial pathogenesis. Type 1 pili are important virulence factors in uropathogenic Escherichia coli (UPEC), which cause the majority of urinary tract infections (UTI). FimH, the type 1 adhesin, binds mannosylated glycoproteins on the surface of human and murine bladder cells, facilitating bacterial colonization, invasion, and formation of biofilm-like intracellular bacterial communities. The mannose-binding pocket of FimH is invariant among UPEC. We discovered that pathoadaptive alleles of FimH with variant residues outside the binding pocket affect FimH-mediated acute and chronic pathogenesis of two commonly studied UPEC strains, UTI89 and CFT073. In vitro binding studies revealed that, whereas all pathoadaptive variants tested displayed the same high affinity for mannose when bound by the chaperone FimC, affinities varied when FimH was incorporated into pilus tip-like, FimCGH complexes. Structural studies have shown that FimH adopts an elongated conformation when complexed with FimC, but, when incorporated into the pilus tip, FimH can adopt a compact conformation. We hypothesize that the propensity of FimH to adopt the elongated conformation in the tip corresponds to its mannose binding affinity. Interestingly, FimH variants, which maintain a high-affinity conformation in the FimCGH tip-like structure, were attenuated during chronic bladder infection, implying that FimH's ability to switch between conformations is important in pathogenesis. Our studies argue that positively selected residues modulate fitness during UTI by affecting FimH conformation and function, providing an example of evolutionary tuning of structural dynamics impacting in vivo survival.
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Abstract
Uropathogenic Escherichia coli (UPEC) is the leading cause of urinary tract infections in women, causing significant morbidity and mortality in this population. Adherence to host epithelial cells is a pivotal step in the pathogenesis of UPEC. One of the most important virulence factors involved in mediating this attachment is the type 1 pilus (type 1 fimbria) encoded by a set of fim genes arranged in an operon. The expression of type 1 pili is controlled by a phenomenon known as phase variation, which reversibly switches between the expression of type 1 pili (Phase-ON) and loss of expression (Phase-OFF). Phase-ON cells have the promoter for the fimA structural gene on an invertible DNA element called fimS, which lines up to allow transcription, whereas transcription of the structural gene is silenced in Phase-OFF cells. The orientation of the fimS invertible element is controlled by two site-specific recombinases, FimB and FimE. Environmental conditions cause transcriptional and post-transcriptional changes in UPEC cells that affect the level of regulatory proteins, which in turn play vital roles in modulating this phase switching ability. The role of fim gene regulation in UPEC pathogenesis will be discussed.
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Scharenberg M, Abgottspon D, Cicek E, Jiang X, Schwardt O, Rabbani S, Ernst B. A Flow Cytometry-Based Assay for Screening FimH Antagonists. Assay Drug Dev Technol 2011; 9:455-64. [DOI: 10.1089/adt.2010.0357] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Meike Scharenberg
- Institute of Molecular Pharmacy, Pharmacenter, University of Basel, Basel, Switzerland
| | - Daniela Abgottspon
- Institute of Molecular Pharmacy, Pharmacenter, University of Basel, Basel, Switzerland
| | - Evelin Cicek
- Institute of Molecular Pharmacy, Pharmacenter, University of Basel, Basel, Switzerland
| | - Xiaohua Jiang
- Institute of Molecular Pharmacy, Pharmacenter, University of Basel, Basel, Switzerland
| | - Oliver Schwardt
- Institute of Molecular Pharmacy, Pharmacenter, University of Basel, Basel, Switzerland
| | - Said Rabbani
- Institute of Molecular Pharmacy, Pharmacenter, University of Basel, Basel, Switzerland
| | - Beat Ernst
- Institute of Molecular Pharmacy, Pharmacenter, University of Basel, Basel, Switzerland
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Korea CG, Ghigo JM, Beloin C. The sweet connection: Solving the riddle of multiple sugar-binding fimbrial adhesins in Escherichia coli. Bioessays 2011; 33:300-11. [DOI: 10.1002/bies.201000121] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Rabbani S, Jiang X, Schwardt O, Ernst B. Expression of the carbohydrate recognition domain of FimH and development of a competitive binding assay. Anal Biochem 2010; 407:188-95. [DOI: 10.1016/j.ab.2010.08.007] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2010] [Revised: 07/26/2010] [Accepted: 08/04/2010] [Indexed: 10/19/2022]
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Antão EM, Wieler LH, Ewers C. Adhesive threads of extraintestinal pathogenic Escherichia coli. Gut Pathog 2009; 1:22. [PMID: 20003270 PMCID: PMC2797515 DOI: 10.1186/1757-4749-1-22] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2009] [Accepted: 12/10/2009] [Indexed: 12/25/2022] Open
Abstract
The ability to adhere to host surfaces is by far the most vital step in the successful colonization by microbial pathogens. Colonization begins with the attachment of the bacterium to receptors expressed by cells forming the lining of the mucosa. Long hair like extracellular appendages called fimbriae, produced by most Gram-negative pathogens, mediate specific attachment to the epithelial cell surface. Associated with the fimbriae is a protein called an adhesin, which directs high-affinity binding to specific cell surface components. In the last couple of years, an enormous amount of research has been undertaken that deals with understanding how bacterial pathogens adhere to host cells. E. coli in all probability is one of the best studied free-living organisms. A group of E. coli called Extraintestinal pathogenic E. coli (ExPEC) including both human and animal pathogens like Uropathogenic E. coli (UPEC), Newborn meningitic E. coli (NMEC) and Avian pathogenic E. coli (APEC), have been found to harbour many fimbriae including Type 1 fimbriae, P fimbriae, curli fibres, S fimbriae, F1C fimbriae, Dr fimbriae, afimbrial adhesins, temperature-sensitive haemagglutinin and many novel adhesin gene clusters that have not yet been characterized. Each of these adhesins is unique due to the recognition of an adhesin-specific receptor, though as a group these adhesins share common genomic organization. A newly identified putative adhesin temporarily termed ExPEC Adhesin I, encoded by gene yqi, has been recently found to play a significant role in the pathogenesis of APEC infection, thus making it an interesting candidate for future research. The aim of this review is to describe the role of ExPEC adhesins during extraintestinal infections known till date, and to suggest the idea of investigating their potential role in the colonization of the host gut which is said to be a reservoir for ExPEC.
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Affiliation(s)
- Esther-Maria Antão
- Institut für Mikrobiologie und Tierseuchen, Freie Universität Berlin, Philippstr, 13, 10115 Berlin, Germany.
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15
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Shin S, Kim KS. Human brain endothelial ATP synthase beta-subunit is mannose-insensitive binding target of FimH. FEMS Microbiol Lett 2009; 303:156-62. [PMID: 20067530 DOI: 10.1111/j.1574-6968.2009.01878.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Binding of meningitis-causing Escherichia coli K1 to human brain microvascular endothelial cells (HBMEC) contributes to traversal of the blood-brain barrier, which occurs in part by the mannose-sensitive binding of FimH. In this study, we showed that FimH also binds to HBMEC, independent of mannose, and identified ATP synthase beta-subunit and actin proteins from the surface biotinylated HBMEC as the mannose-insensitive binding targets for FimH. Co-immunoprecipitation experiments in the presence of alpha-methyl mannose verified the binding of FimH to ATP synthase beta-subunit of HBMEC. ATP synthase beta-subunit antibody decreased E. coli K1 binding to HBMEC in the presence of alpha-methyl mannose. Taken together, these findings demonstrate that FimH of E. coli K1 binds to HBMEC in both mannose-sensitive and -insensitive manner.
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Affiliation(s)
- Sooan Shin
- Division of Pediatric Infectious Diseases, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
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16
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Antão EM, Ewers C, Gürlebeck D, Preisinger R, Homeier T, Li G, Wieler LH. Signature-tagged mutagenesis in a chicken infection model leads to the identification of a novel avian pathogenic Escherichia coli fimbrial adhesin. PLoS One 2009; 4:e7796. [PMID: 19907658 PMCID: PMC2771359 DOI: 10.1371/journal.pone.0007796] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2009] [Accepted: 10/07/2009] [Indexed: 11/23/2022] Open
Abstract
The extraintestinal pathogen, avian pathogenic E. coli (APEC), known to cause systemic infections in chickens, is responsible for large economic losses in the poultry industry worldwide. In order to identify genes involved in the early essential stages of pathogenesis, namely adhesion and colonization, Signature-tagged mutagenesis (STM) was applied to a previously established lung colonization model of infection by generating and screening a total of 1,800 mutants of an APEC strain IMT5155 (O2:K1:H5; Sequence type complex 95). The study led to the identification of new genes of interest, including two adhesins, one of which coded for a novel APEC fimbrial adhesin (Yqi) not described for its role in APEC pathogenesis to date. Its gene product has been temporarily designated ExPEC Adhesin I (EA/I) until the adhesin-specific receptor is identified. Deletion of the ExPEC adhesin I gene resulted in reduced colonization ability by APEC strain IMT5155 both in vitro and in vivo. Furthermore, complementation of the adhesin gene restored its ability to colonize epithelial cells in vitro. The ExPEC adhesin I protein was successfully expressed in vitro. Electron microscopy of an afimbriate strain E. coli AAEC189 over-expressed with the putative EA/I gene cluster revealed short fimbrial-like appendages protruding out of the bacterial outer membrane. We observed that this adhesin coding gene yqi is prevalent among extraintestinal pathogenic E. coli (ExPEC) isolates, including APEC (54.4%), uropathogenic E. coli (UPEC) (65.9%) and newborn meningitic E. coli (NMEC) (60.0%), and absent in all of the 153 intestinal pathogenic E. coli strains tested, thereby validating the designation of the adhesin as ExPEC Adhesin I. In addition, prevalence of EA/I was most frequently associated with the B2 group of the EcoR classification and ST95 complex of the multi locus sequence typing (MLST) scheme, with evidence of a positive selection within this highly pathogenic complex. This is the first report of the newly identified and functionally characterized ExPEC adhesin I and its significant role during APEC infection in chickens.
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Affiliation(s)
- Esther-Maria Antão
- Institut für Mikrobiologie und Tierseuchen, Freie Universität Berlin, Berlin, Germany.
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17
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Tiels P, Verdonck F, Coddens A, Goddeeris B, Cox E. The excretion of F18+ E. coli is reduced after oral immunisation of pigs with a FedF and F4 fimbriae conjugate. Vaccine 2008; 26:2154-63. [PMID: 18543416 DOI: 10.1016/j.vaccine.2008.01.054] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Currently, no vaccines are available for edema disease and post-weaning diarrhoea (PWD) in pigs. In the present study, a subunit vaccine containing the F18 fimbrial adhesin FedF was studied. Hereto, recombinant FedF was produced as a fusion protein with maltose-binding protein. Even though the produced MBPFedF was shown to attach in vitro to enterocytes, almost no FedF-specific immune response could be detected after oral administration to piglets. The delivery of FedF to the intestinal mucosa was improved by conjugating the MBPFedF to F4 fimbriae. Indeed, this conjugation induced a systemic and local FedF-specific immune response and led to a reduction in excretion after infection with F18+ E. coli. Although complete protection was not observed, the conjugation between FedF and F4 fimbriae can be considered as a first step towards the development of a combined vaccine against F4+ and F18+ E. coli infections.
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Affiliation(s)
- P Tiels
- Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium
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18
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Bergsten G, Wullt B, Schembri MA, Leijonhufvud I, Svanborg C. Do type 1 fimbriae promote inflammation in the human urinary tract? Cell Microbiol 2007; 9:1766-81. [PMID: 17359236 DOI: 10.1111/j.1462-5822.2007.00912.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Type 1 fimbriae have been implicated as virulence factors in animal models of urinary tract infection (UTI), but the function in human disease remains unclear. This study used a human challenge model to examine if type 1 fimbriae trigger inflammation in the urinary tract. The asymptomatic bacteriuria strain Escherichia coli 83972, which fails to express type 1 fimbriae, due to a 4.25 kb fimB-fimD deletion, was reconstituted with a functional fim gene cluster and fimbrial expression was monitored through a gfp reporter. Each patient was inoculated with the fim+ or fim- variants on separate occasions, and the host response to type 1 fimbriae was quantified by intraindividual comparisons of the responses to the fim+ or fim- isogens, using cytokines and neutrophils as end-points. Type 1 fimbriae did not promote inflammation and adherence was poor, as examined on exfoliated cells in urine. This was unexpected, as type 1 fimbriae enhanced the inflammatory response to the same strain in the murine urinary tract and as P fimbrial expression by E. coli 83972 enhances adherence and inflammation in challenged patients. We conclude that type 1 fimbriae do not contribute to the mucosal inflammatory response in the human urinary tract.
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Affiliation(s)
- Göran Bergsten
- Department of Microbiology, Immunology, and Glycobiology, Lund University, Lund, Sweden
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19
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Abstract
Bacterial adhesion is often a prelude to infection. In many cases, this process is governed by protein-carbohydrate interactions. Intervention at this early stage of infection is a conceptually highly attractive alternative to conventional antibiotics that are increasingly prone to resistance. The lack of high-affinity inhibitors of adhesion has proven to be a hurdle for further exploitation of this concept; however, new developments indicate a positive change. Structure-based design at the monovalent level and also evaluation of glycodendrimers and glycopolymers have yielded structures of high affinity. In addition to the development of inhibitors, topics of this review include available structural information of adhesion proteins, carbohydrate specificities of the various pathogens and their adhesion proteins. Other new developments aimed at affecting bacterial adhesion and the use of the adhesins for bacterial detection are also discussed.
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Affiliation(s)
- Roland J Pieters
- Department of Medicinal Chemistry and Chemical Biology, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, NL-3508 TB Utrecht, The Netherlands.
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20
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Teng CH, Xie Y, Shin S, Di Cello F, Paul-Satyaseela M, Cai M, Kim KS. Effects of ompA deletion on expression of type 1 fimbriae in Escherichia coli K1 strain RS218 and on the association of E. coli with human brain microvascular endothelial cells. Infect Immun 2006; 74:5609-16. [PMID: 16988236 PMCID: PMC1594875 DOI: 10.1128/iai.00321-06] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We have previously shown that outer membrane protein A (OmpA) and type 1 fimbriae are the bacterial determinants involved in Escherichia coli K1 binding to human brain microvascular endothelial cells (HBMEC), which constitute the blood-brain barrier. In investigating the role of OmpA in E. coli K1 binding to HBMEC, we showed for the first time that ompA deletion decreased the expression of type 1 fimbriae in E. coli K1. Decreased expression of type 1 fimbriae in the ompA deletion mutant was largely the result of driving the fim promoter toward the type 1 fimbrial phase-OFF orientation. mRNA levels of fimB and fimE were found to be decreased with the OmpA mutant compared to the parent strain. Of interest, the ompA deletion further decreased the abilities of E. coli K1 to bind to and invade HBMEC under the conditions of fixing type 1 fimbria expression in the phase-ON or phase-OFF status. These findings suggest that the decreased ability of the OmpA mutant to interact with HBMEC is not entirely due to its decreased type 1 fimbrial expression and that OmpA and type 1 fimbriae facilitate the interaction of E. coli K1 with HBMEC at least in an additive manner.
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Affiliation(s)
- Ching-Hao Teng
- Division of Clinical Research, National Health Research Institutes, Tainan, Taiwan
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21
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Xie Y, Yao Y, Kolisnychenko V, Teng CH, Kim KS. HbiF regulates type 1 fimbriation independently of FimB and FimE. Infect Immun 2006; 74:4039-47. [PMID: 16790777 PMCID: PMC1489709 DOI: 10.1128/iai.02058-05] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Type 1 fimbriae have been suggested to play a role in the pathogenesis of extraintestinal Escherichia coli infection. Type 1 fimbriation in E. coli is phase variable and known to be dependent upon FimB and FimE, the two recombinases that invert the molecular switch fimS and control the expression of the downstream fim operon. Here we showed that HbiF, a novel site-specific recombinase, inverted fimS independently of FimB and FimE. HbiF-mediated fimS inversion appeared to be predominantly switching from "off" (termed OFF) to "on" (termed ON) orientation. This is different from the fimS inversion mediated by either FimB (bidirectional ON to OFF and OFF to ON) or FimE (unidirectional ON to OFF). Constitutive expression of the hbiF gene in E. coli resulted in a fimS-locked-ON phenotype, which resulted in the pathogenic E. coli K1 strain being incapable of inducing a high degree of bacteremia in neonatal rats. Discovery of HbiF-mediated OFF-to-ON fimS switching provides a new opportunity to develop a strategy for the prevention and therapy of extraintestinal E. coli infection including bacteremia and meningitis.
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Affiliation(s)
- Yi Xie
- Division of Pediatric Infectious Diseases, Johns Hopkins University School of Medicine, 600 North Wolfe St., Park 256, Baltimore, MD 21287, USA
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22
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Weissman SJ, Chattopadhyay S, Aprikian P, Obata-Yasuoka M, Yarova-Yarovaya Y, Stapleton A, Ba-Thein W, Dykhuizen D, Johnson JR, Sokurenko EV. Clonal analysis reveals high rate of structural mutations in fimbrial adhesins of extraintestinal pathogenic Escherichia coli. Mol Microbiol 2006; 59:975-88. [PMID: 16420365 PMCID: PMC1380272 DOI: 10.1111/j.1365-2958.2005.04985.x] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Type 1 fimbriae of Escherichia coli mediate mannose-specific adhesion to host epithelial surfaces and consist of a major, antigenically variable pilin subunit, FimA, and a minor, structurally conserved adhesive subunit, FimH, located on the fimbrial tip. We have analysed the variability of fimA and fimH in strains of vaginal and other origin that belong to one of the most prominent clonal groups of extraintestinal pathogenic E. coli, comprised of O1:K1-, O2:K1- and O18:K1-based serotypes. Multiple locus sequence typing (MLST) of this group revealed that the strains have identical (at all but one nucleotide position) eight housekeeping loci around the genome and belong to the ST95 complex defined by the publicly available E. coli MLST database. Multiple highly diverse fimA alleles have been introduced into the ST95 clonal complex via horizontal transfer, at a frequency comparable to that of genes defining the major O- and H-antigens. However, no further significant FimA diversification has occurred via point mutation after the transfers. In contrast, while fimH alleles also move horizontally (along with the fimA loci), they acquire point amino acid replacements at a higher rate than either housekeeping genes or fimA. These FimH mutations enhance binding to monomannose receptors and bacterial tropism for human vaginal epithelium. A similar pattern of rapid within-clonal structural evolution of the adhesive, but not pilin, subunit is also seen, respectively, in papG and papA alleles of the di-galactose-specific P-fimbriae. Thus, while structurally diverse pilin subunits of E. coli fimbriae are under selective pressure for frequent horizontal transfer between clones, the adhesive subunits of extraintestinal E. coli are under strong positive selection (Dn/Ds > 1 for fimH and papG) for functionally adaptive amino acid replacements.
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Affiliation(s)
- Scott J. Weissman
- Division of Infectious Disease, Immunology and Rheumatology, Department of Pediatrics, University of Washington, Seattle, WA, USA
| | | | - Pavel Aprikian
- Department of Microbiology, University of Washington, Seattle, WA, USA
| | - Mana Obata-Yasuoka
- Department of Obstetrics/Gynecology, University of Tsukuba, Tsukuba, Japan
| | - Yuliya Yarova-Yarovaya
- Division of Allergy and Infectious Disease, Department of Medicine, University of Washington, Seattle, WA, USA
| | - Ann Stapleton
- Division of Allergy and Infectious Disease, Department of Medicine, University of Washington, Seattle, WA, USA
| | - William Ba-Thein
- Department of Microbiology/Immunology, Thammasit University, Pathum-Thani, Thailand
| | - Daniel Dykhuizen
- Department of Evolutionary Biology, State University of New York, Stony Brook, NY, USA
| | - James R. Johnson
- Mucosal and Vaccine Research Center, Minneapolis VA Medical Center, University of Minnesota, Minneapolis, MN, USA
- Department of Medicine, University of Minnesota, Minneapolis, MN, USA
| | - Evgeni V. Sokurenko
- Department of Microbiology, University of Washington, Seattle, WA, USA
- *For correspondence. E-mail ; Tel. (+1) 206 685 2162; Fax (+1) 206 543 8297
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23
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Bergsten G, Wullt B, Svanborg C. Escherichia coli, fimbriae, bacterial persistence and host response induction in the human urinary tract. Int J Med Microbiol 2005; 295:487-502. [PMID: 16238023 DOI: 10.1016/j.ijmm.2005.07.008] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Urinary tract infections (UTI) are among the most common bacterial infections in humans. Symptomatic UTIs may be acute, recurrent or chronic but the most frequent form of UTI is asymptomatic bacteruria (ABU). In ABU, the mucosa remains inert, despite the presence of large bacterial numbers in urine. The difference in disease severity reflects the virulence of the infecting strain and the propensity of the host to respond to infection. It is essential to understand the molecular basis of disease diversity and the molecular interactions between bacteria and host that determine asymptomatic carriage and the transition to disease. We discuss the initial interactions between bacteria and the mucosal surfaces in the human urinary tract, and the bacterial factors involved in the breach of mucosal inertia. Specifically, the contribution of P and type 1 fimbriae to bacterial establishment and host response induction are investigated. The results show that P fimbriae serve as independent virulence factors when expressed by an ABU strain, by promoting the establishment of bacteriuria and the innate host response, which is the cause of symptoms and tissue damage. P fimbriae thus fulfil the molecular Koch postulates as independent virulence factors in the human urinary tract. Type 1 fimbriae, in contrast, did not act as virulence factors in this model, and thus appear to serve a different function in man than in the murine model.
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Affiliation(s)
- Göran Bergsten
- Department of Microbiology, Immunology and Glycobiology, Institute of Laboratory Medicine, Lund University, Lund, Sweden
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24
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Duncan MJ, Mann EL, Cohen MS, Ofek I, Sharon N, Abraham SN. The Distinct Binding Specificities Exhibited by Enterobacterial Type 1 Fimbriae Are Determined by Their Fimbrial Shafts. J Biol Chem 2005; 280:37707-16. [PMID: 16118220 DOI: 10.1074/jbc.m501249200] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Type 1 fimbriae of enterobacteria are heteropolymeric organelles of adhesion composed of FimH, a mannose-binding lectin, and a shaft composed primarily of FimA. We compared the binding activities of recombinant clones expressing type 1 fimbriae from Escherichia coli, Klebsiella pneumoniae, and Salmonella typhimurium for gut and uroepithelial cells and for various soluble mannosylated proteins. Each fimbria was characterized by its capacity to bind particular epithelial cells and to aggregate mannoproteins. However, when each respective FimH subunit was cloned and expressed in the absence of its shaft as a fusion protein with MalE, each FimH bound a wide range of mannose-containing compounds. In addition, we found that expression of FimH on a heterologous fimbrial shaft, e.g. K. pneumoniae FimH on the E. coli fimbrial shaft or vice versa, altered the binding specificity of FimH such that it closely resembled that of the native heterologous type 1 fimbriae. Furthermore, attachment to and invasion of bladder epithelial cells, which were mediated much better by native E. coli type 1 fimbriae compared with native K. pneumoniae type 1 fimbriae, were found to be dependent on the background of the fimbrial shaft (E. coli versus K. pneumoniae) rather than the background of the FimH expressed. Thus, the distinct binding specificities of different enterobacterial type 1 fimbriae cannot be ascribed solely to the primary structure of their respective FimH subunits, but are also modulated by the fimbrial shaft on which each FimH subunit is presented, possibly through conformational constraints imposed on FimH by the fimbrial shaft. The capacity of type 1 fimbrial shafts to modulate the tissue tropism of different enterobacterial species represents a novel function for these highly organized structures.
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Affiliation(s)
- Matthew J Duncan
- Molecular Genetics and Microbiology and Pathology, Duke University Medical Center, Durham, NC 27710, USA
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25
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Serafini-Cessi F, Monti A, Cavallone D. N-Glycans carried by Tamm-Horsfall glycoprotein have a crucial role in the defense against urinary tract diseases. Glycoconj J 2005; 22:383-94. [PMID: 16622944 DOI: 10.1007/s10719-005-2142-z] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Tamm-Horsfall glycoprotein (THGP), produced exclusively by renal cells from the thick ascending limb of Henle's loop, is attached by a glycosyl-phosphatidylinositol (GPI)-anchor to the luminal face of the cells. Urinary excretion of THGP (50-100 mg/day) occurs upon proteolytic cleavage of the large ectodomain of the GPI-anchored form. N-Glycans, consisting of a large repertoire of sialylated polyantennary chains and high-mannose structures, account for approximately 30% of the weight of human urinary THGP. We describe: (i) the involvement of urinary THGP high-mannose glycans in defense against infections of the urinary tract, caused by type-1 fimbriated Escherichia coli, which recognize high-mannose structures, (ii) the role of GalNAcbeta1-4(NeuAcalpha2-3)Galbeta1-4GlcNAcbeta1-3Gal (Sd(a) determinant) carried by human THGP in protecting the distal nephron from colonization of type-S fimbriated E. coli which recognise NeuAcalpha2-3Gal, (iii) the inhibitory effect of sialylated THGP on crystal aggregation of calcium oxalate and calcium phosphate, thus preventing nephrolithiasis. Finally, we outline the importance of N-glycans in promoting the polymerization of THGP, a process resulting in the formation of homopolymers with an M(r) of several million in urine. Since THGP defense against diseases of the urinary tract mainly consists in binding damaging agents, its ability to behave as a multivalent ligand significantly enhances this protective role.
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Affiliation(s)
- Franca Serafini-Cessi
- Department of Experimental Pathology, University of Bologna, Italy. serafini@.alma.unibo.it
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26
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Teng CH, Cai M, Shin S, Xie Y, Kim KJ, Khan NA, Di Cello F, Kim KS. Escherichia coli K1 RS218 interacts with human brain microvascular endothelial cells via type 1 fimbria bacteria in the fimbriated state. Infect Immun 2005; 73:2923-31. [PMID: 15845498 PMCID: PMC1087349 DOI: 10.1128/iai.73.5.2923-2931.2005] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Escherichia coli K1 is a major gram-negative organism causing neonatal meningitis. E. coli K1 binding to and invasion of human brain microvascular endothelial cells (HBMEC) are a prerequisite for E. coli penetration into the central nervous system in vivo. In the present study, we showed using DNA microarray analysis that E. coli K1 associated with HBMEC expressed significantly higher levels of the fim genes compared to nonassociated bacteria. We also showed that E. coli K1 binding to and invasion of HBMEC were significantly decreased with its fimH deletion mutant and type 1 fimbria locked-off mutant, while they were significantly increased with its type 1 fimbria locked-on mutant. E. coli K1 strains associated with HBMEC were predominantly type 1 fimbria phase-on (i.e., fimbriated) bacteria. Taken together, we showed for the first time that type 1 fimbriae play an important role in E. coli K1 binding to and invasion of HBMEC and that type 1 fimbria phase-on E. coli is the major population interacting with HBMEC.
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Affiliation(s)
- Ching-Hao Teng
- Division of Pediatric Infectious Diseases, School of Medicine, Johns Hopkins University, Baltimore, MD 21287, USA
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27
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Affiliation(s)
- T Feizi
- Glycoconjugates Section, Clinical Research Centre, Watford Road, Harrow, Middlesex, HA1 3UJ, UK
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28
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Novel multivalent mannose compounds and their inhibition of the adhesion of type 1 fimbriated uropathogenic E. coli. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/j.tetasy.2004.11.014] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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29
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Kariyawasam S, Wilkie BN, Gyles CL. Resistance of broiler chickens to Escherichia coli respiratory tract infection induced by passively transferred egg-yolk antibodies. Vet Microbiol 2004; 98:273-84. [PMID: 15036536 DOI: 10.1016/j.vetmic.2003.10.022] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2003] [Revised: 10/08/2003] [Accepted: 10/27/2003] [Indexed: 11/18/2022]
Abstract
Egg-yolk antibodies induced by immunizing hens with selected Escherichia coli antigens were evaluated for their ability to protect broiler chickens against respiratory/septicemic disease caused by avian pathogenic E. coli (APEC). Seven groups of broiler breeder hens were vaccinated three times, 1 week apart with live E. coli, killed E. coli, E. coli antigens [lipopolysaccharide (LPS), type 1 pilus adhesin (FimH), P pilus adhesin (PapG), aerobactin outer membrane receptor (IutA)] or phosphate buffered saline (PBS). An O78 APEC strain was used for preparation of all the antigens. Egg yolk immunoglobulins (IgY) were purified from eggs of each group and antibody activity in serum and purified IgY was determined by enzyme-linked immunosorbent assay (ELISA). IgY (100mg) was injected intramuscularly into 11-day-old broiler chickens, which were challenged 3 days later with homologous (O78) or heterologous (O1 or O2) E. coli by the intra-air sac route. Mortality was recorded and surviving chickens were euthanized 1 week after the challenge and examined for macroscopic lesions. Passive antibodies against all antigens except FimH were protective (90-100%) against the homologous challenge, but only anti-PapG and anti-IutA were effective against heterologous challenge. Anti-PapG IgY provided the greatest protection against the three serogroups of E. coli used for challenge. Hence vaccination of broiler breeders to induce anti-PapG and anti-IutA antibodies may provide passive protection of progeny chicks against respiratory/septicemic disease caused by APEC.
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Affiliation(s)
- S Kariyawasam
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ont., Canada N1G 2W1
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30
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Mo L, Zhu XH, Huang HY, Shapiro E, Hasty DL, Wu XR. Ablation of the Tamm-Horsfall protein gene increases susceptibility of mice to bladder colonization by type 1-fimbriated Escherichia coli. Am J Physiol Renal Physiol 2003; 286:F795-802. [PMID: 14665435 DOI: 10.1152/ajprenal.00357.2003] [Citation(s) in RCA: 134] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The adhesion of uropathogenic Escherichia coli to the urothelial surface of the bladder is a prerequisite for the establishment of bladder infections. This adhesion process relies on E. coli adhesins and their cognate urothelial receptors, and it also is influenced by an intricate array of defense mechanisms of the urinary system. In this study, we examined the in vivo role of Tamm-Horsfall protein (THP), the most abundant urinary protein, in innate urinary defense. We genetically ablated the mouse THP gene and found that THP deficiency predisposes mice to bladder infections by type 1-fimbriated E. coli. Inoculation of too few type 1-fimbriated E. coli to colonize wild-type mice caused significant bladder colonization in THP-knockout mice. In contrast, THP deficiency did not enhance the ability of P-fimbriated E. coli to colonize the bladder. Our results provide the first in vivo evidence indicating that under physiological conditions, the mannosylated THP can serve as an effective soluble "receptor," binding to the type 1-fimbriated E. coli and competitively inhibiting them from adhering to the uroplakin Ia receptors present on the urothelial surface. These results suggest that potential THP defects, either quantitative or qualitative, could predispose the urinary bladder to bacterial infections. The generation of THP-deficient mice established the role of THP as a first line of urinary defense and should help elucidate other potential functions of this major protein in urinary tract physiology and diseases.
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Affiliation(s)
- Lan Mo
- Dept. of Urology, New York Univ. School of Medicine, 423 East 23 St., 18th Floor, Rm. 18064 South, New York, NY 10010, USA.
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31
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Langermann S, Ballou WR. Development of a recombinant FimCH vaccine for urinary tract infections. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2003; 539:635-48. [PMID: 15176317 DOI: 10.1007/978-1-4419-8889-8_41] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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32
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Abstract
An elementary step in the assembly of adhesive type 1 pili of Escherichia coli is the folding of structural pilus subunits in the periplasm. The previously determined X-ray structure of the complex between the type 1 pilus adhesin FimH and the periplasmic pilus assembly chaperone FimC has shown that FimH consists of a N-terminal lectin domain and a C-terminal pilin domain, and that FimC exclusively interacts with the pilin domain. The pilin domain fold, which is common to all pilus subunits, is characterized by an incomplete beta-sheet that is completed by a donor strand from FimC in the FimC-FimH complex. This, together with unsuccessful attempts to refold isolated, urea-denatured FimH in vitro had suggested that folding of pilin domains strictly depends on sequence information provided by FimC. We have now analyzed in detail the folding of FimH and its two isolated domains in vitro. We find that not only the lectin domain, but also the pilin domain can fold autonomously and independently of FimC. However, the thermodynamic stability of the pilin domain is very low (8-10kJmol(-1)) so that a significant fraction of the domain is unfolded even in the absence of denaturant. This explains the high tendency of structural pilus subunits to aggregate non-specifically in the absence of stoichiometric amounts of FimC. Thus, pilus chaperones prevent non-specific aggregation of pilus subunits by native state stabilization after subunit folding.
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Affiliation(s)
- Michael Vetsch
- Institut für Molekularbiologie und Biophysik, Eidgenössische Technische Hochschule Hönggerberg, CH-8093 Zurich, Switzerland
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Lifshitz S, Dagan R, Shani-Sekler M, Grossman N, Fleminger G, Friger M, Nebenzahl YM. Age-dependent preference in human antibody responses to Streptococcus pneumoniae polypeptide antigens. Clin Exp Immunol 2002; 127:344-53. [PMID: 11876760 PMCID: PMC1906324 DOI: 10.1046/j.1365-2249.2002.01745.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/12/2001] [Indexed: 11/20/2022] Open
Abstract
Vulnerability to Streptococcus pneumoniae is most pronounced in children. The microbial virulence factors and the features of the host immune response contributing to this phenomenon are not completely understood. In the current study, the humoral immune response to separated Strep. pneumoniae surface proteins and the ability to interfere with Strep. pneumoniae adhesion to cultured epithelial cells were analysed in adults and in children. Sera collected from healthy adults recognized Strep. pneumoniae separated lectin and nonlectin surface proteins in Western blot analysis and inhibited on average 80% of Strep. pneumoniae adhesion to epithelial cells in a concentration-dependent manner. However, sera longitudinally collected from healthy children attending day care centres from 18 months of age and over the course of the following 2 years revealed: (a) development of antibodies to previously unrecognized Strep. pneumoniae surface proteins with age; (b) a quantitative increase in antibody responses, measured by densitometry, towards separated Strep. pneumoniae surface proteins with age; and (c) inhibition of Strep. pneumoniae adhesion to epithelial cells, which was 50% on average at 18 months of age, increased significantly to an average level of 80% inhibition at 42 months of age equalling adult sera inhibitory values. The results obtained in the current study, from the longitudinally collected sera from healthy children with documented repeated Strep. pneumoniae colonization, show that repeated exposures are insufficient to elicit an immune response to Strep. pneumoniae proteins at 18 months of age. This inability to recognize Strep. pneumoniae surface proteins may stem from the inefficiency of T-cell-dependent B-cell responses at this age and/or from the low immunogenicity of the proteins.
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Affiliation(s)
- S Lifshitz
- Paediatric Infectious Disease Unit, Soroka University Medical Centre, Tel Aviv, Israel
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Iida K, Mizunoe Y, Wai SN, Yoshida S. Type 1 fimbriation and its phase switching in diarrheagenic Escherichia coli strains. CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY 2001; 8:489-95. [PMID: 11329445 PMCID: PMC96088 DOI: 10.1128/cdli.8.3.489-495.2001] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Type 1 fimbriae can be expressed by most Escherichia coli strains and mediate mannose-sensitive (MS) adherence to mammalian epithelial cells. However, the role of type 1 fimbriae in enteric pathogenesis has been unclear. Expression of type 1 fimbriae in E. coli is phase variable and is associated with the inversion of a short DNA element (fim switch). Forty-six strains of diarrheagenic E. coli were examined for the expression of type 1 fimbriae. Only four of these strains were originally type 1 fimbriated. Seventeen strains, originally nonfimbriated, expressed type 1 fimbriae in association with off-to-on inversion of the fim switch, after serial passages in static culture. The switching frequencies of these strains, from fimbriate to nonfimbriate, were greater than that of the laboratory strain E. coli K-12. None of the 16 strains of serovar O157:H7 or O157:H(-) expressed type 1 fimbriae after serial passages in static culture. The nucleotide sequence analysis of the fim switch region revealed that all of the O157:H7 and O157:H(-) strains had a 16-bp deletion in the invertible element, and the fim switch was locked in the "off" orientation. The results suggest that expression of type 1 fimbriae may be regulated differently in different E. coli pathogens causing enteric infections.
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Affiliation(s)
- K Iida
- Department of Bacteriology, Faculty of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan
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35
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Townsend SM, Kramer NE, Edwards R, Baker S, Hamlin N, Simmonds M, Stevens K, Maloy S, Parkhill J, Dougan G, Bäumler AJ. Salmonella enterica serovar Typhi possesses a unique repertoire of fimbrial gene sequences. Infect Immun 2001; 69:2894-901. [PMID: 11292704 PMCID: PMC98240 DOI: 10.1128/iai.69.5.2894-2901.2001] [Citation(s) in RCA: 127] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2000] [Accepted: 01/29/2001] [Indexed: 12/21/2022] Open
Abstract
Salmonella enterica serotype Typhi differs from nontyphoidal Salmonella serotypes by its strict host adaptation to humans and higher primates. Since fimbriae have been implicated in host adaptation, we investigated whether the serotype Typhi genome contains fimbrial operons which are unique to this pathogen or restricted to typhoidal Salmonella serotypes. This study established for the first time the total number of fimbrial operons present in an individual Salmonella serotype. The serotype Typhi CT18 genome, which has been sequenced by the Typhi Sequencing Group at the Sanger Centre, contained a type IV fimbrial operon, an orthologue of the agf operon, and 12 putative fimbrial operons of the chaperone-usher assembly class. In addition to sef, fim, saf, and tcf, which had been described previously in serotype Typhi, we identified eight new putative chaperone-usher-dependent fimbrial operons, which were termed bcf, sta, stb, ste, std, stc, stg, and sth. Hybridization analysis performed with 16 strains of Salmonella reference collection C and 22 strains of Salmonella reference collection B showed that all eight putative fimbrial operons of serotype Typhi were also present in a number of nontyphoidal Salmonella serotypes. Thus, a simple correlation between host range and the presence of a single fimbrial operon seems at present unlikely. However, the serotype Typhi genome differed from that of all other Salmonella serotypes investigated in that it contained a unique combination of putative fimbrial operons.
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Affiliation(s)
- S M Townsend
- Department of Medical Microbiology and Immunology, College of Medicine, Texas A&M University, College Station, Texas 77843, USA
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36
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Metzler DE, Metzler CM, Sauke DJ. How Macromolecules Associate. Biochemistry 2001. [DOI: 10.1016/b978-012492543-4/50010-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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37
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Kjaergaard K, Sørensen JK, Schembri MA, Klemm P. Sequestration of zinc oxide by fimbrial designer chelators. Appl Environ Microbiol 2000; 66:10-4. [PMID: 10618196 PMCID: PMC91778 DOI: 10.1128/aem.66.1.10-14.2000] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Type 1 fimbriae are surface organelles of Escherichia coli. By engineering a structural component of the fimbriae, FimH, to display a random peptide library, we were able to isolate metal-chelating bacteria. A library consisting of 4 x 10(7) independent clones was screened for binding to ZnO. Sequences responsible for ZnO adherence were identified, and distinct binding motifs were characterized. The sequences selected exhibited various degrees of affinity and specificity towards ZnO. Competitive binding experiments revealed that the sequences recognized only the oxide form of Zn. Interestingly, one of the inserts exhibited significant homology to a specific sequence in a putative zinc-containing helicase, which suggests that searches such as this one may aid in identifying binding motifs in nature. The zinc-binding bacteria might have a use in detoxification of metal-polluted water.
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Affiliation(s)
- K Kjaergaard
- Department of Microbiology, Technical University of Denmark, DK-2800 Lyngby, Denmark
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38
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Thankavel K, Shah AH, Cohen MS, Ikeda T, Lorenz RG, Curtiss R, Abraham SN. Molecular basis for the enterocyte tropism exhibited by Salmonella typhimurium type 1 fimbriae. J Biol Chem 1999; 274:5797-809. [PMID: 10026202 DOI: 10.1074/jbc.274.9.5797] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Salmonella typhimurium exhibits a distinct tropism for mouse enterocytes that is linked to their expression of type 1 fimbriae. The distinct binding traits of Salmonella type 1 fimbriae is also reflected in their binding to selected mannosylated proteins and in their ability to promote secondary bacterial aggregation on enterocyte surfaces. The determinant of binding in Salmonella type 1 fimbriae is a 35-kDa structurally distinct fimbrial subunit, FimHS, because inactivation of fimHS abolished binding activity in the resulting mutant without any apparent effect on fimbrial expression. Surprisingly, when expressed in the absence of other fimbrial components and as a translational fusion protein with MalE, FimHS failed to demonstrate any specific binding tropism and bound equally to all cells and mannosylated proteins tested. To determine if the binding specificity of Salmonella type 1 fimbriae was determined by the fimbrial shaft that is intimately associated with FimHS, we replaced the amino-terminal half of FimHS with the corresponding sequence from Escherichia coli FimH (FimHE) that contains the receptor binding domain of FimHE. The resulting hybrid fimbriae bearing FimHES on a Salmonella fimbrial shaft exhibited binding traits that resembled that of Salmonella rather than E. coli fimbriae. Apparently, the quaternary constraints imposed by the fimbrial shaft on the adhesin determine the distinct binding traits of S. typhimurium type 1 fimbriae.
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Affiliation(s)
- K Thankavel
- Departments of Pathology and Microbiology, Duke University Medical Center, Durham, North Carolina 27710, USA.
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39
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Abstract
Blocking the primary stages of infection, namely bacterial attachment to host cell receptors and colonization of the mucosal surface, may be the most effective strategy to prevent bacterial infections. Bacterial attachment usually involves an interaction between a bacterial surface protein called an adhesin and the host cell receptor. Recent preclinical vaccine studies with the FimH adhesin (derived from uropathogenic Escherichia coli) have confirmed that antibodies elicited against an adhesin can impede colonization, block infection, and prevent disease. The studies indicate that prophylactic vaccination with adhesins can block bacterial infections. With recent advances in the identification, characterization, and isolation of other adhesins, similar approaches are being explored to prevent infections, from otitis media and dental caries to pneumonia and sepsis.
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Affiliation(s)
- T M Wizemann
- MedImmune, Inc., Gaithersburg, Maryland 20878, USA
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40
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Klier CM, Roble AG, Kolenbrander PE. Actinomyces serovar WVA963 coaggregation-defective mutant strain PK2407 secretes lactose-sensitive adhesin that binds to coaggregation partner Streptococcus oralis 34. ORAL MICROBIOLOGY AND IMMUNOLOGY 1998; 13:337-40. [PMID: 9872108 DOI: 10.1111/j.1399-302x.1998.tb00688.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Actinomyces serovar WVA963 strain PK1259 mediates intergeneric coaggregation with several oral streptococci. These lactose-inhibitable coaggregations appear to involve a 95-kDa putative actinomyces adhesin in complex with type 2 fimbriae. A coaggregation-defective strain PK2407 lacking type 2 fimbriae synthesizes the putative adhesin but appears unable to present it properly on its surface. Antiserum was raised against surface sonicates of PK2407 and was absorbed with a different coaggregation-defective mutant PK3092 that synthesizes type 2 fimbriae but no adhesin. This absorbed antiserum specifically blocked lactose-inhibitable coaggregation of wild-type strain PK1259 and Streptococcus oralis 34 and identified a 95-kDa protein in ammonium sulfate precipitates of culture supernatant of the coaggregation-defective mutant PK2407. The 95-kDa secreted protein was bound to the streptococcal partner cells and to lactose-agarose affinity beads and was released by lactose from both the affinity beads and partner, indicating that the secreted and precipitated protein is biochemically active and may mediate coaggregation with streptococci.
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Affiliation(s)
- C M Klier
- Oral Infection and Immunity Branch, National Institute of Dental Research, National Institutes of Health, Bethesda, Maryland 20892-4350, USA
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41
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Pratt LA, Kolter R. Genetic analysis of Escherichia coli biofilm formation: roles of flagella, motility, chemotaxis and type I pili. Mol Microbiol 1998; 30:285-93. [PMID: 9791174 DOI: 10.1046/j.1365-2958.1998.01061.x] [Citation(s) in RCA: 1138] [Impact Index Per Article: 42.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We have used Escherichia coli as a model system to investigate the initiation of biofilm formation. Here, we demonstrate that E. coli forms biofilms on multiple abiotic surfaces in a nutrient-dependent fashion. In addition, we have isolated insertion mutations that render this organism defective in biofilm formation. One-half of these mutations was found to perturb normal flagellar function. Using defined fli, flh, mot and che alleles, we show that motility, but not chemotaxis, is critical for normal biofilm formation. Microscopic analyses of these mutants suggest that motility is important for both initial interaction with the surface and for movement along the surface. In addition, we present evidence that type I pili (harbouring the mannose-specific adhesin, FimH) are required for initial surface attachment and that mannose inhibits normal attachment. In light of the observations presented here, a working model is discussed that describes the roles of both motility and type I pili in biofilm development.
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Affiliation(s)
- L A Pratt
- Department of Microbiology and Molecular Genetics, Harvard Medical School, 200 Longwood Ave, Boston, MA 02115, USA
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42
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Abstract
This map is an update of the edition 9 map by Berlyn et al. (M. K. B. Berlyn, K. B. Low, and K. E. Rudd, p. 1715-1902, in F. C. Neidhardt et al., ed., Escherichia coli and Salmonella: cellular and molecular biology, 2nd ed., vol. 2, 1996). It uses coordinates established by the completed sequence, expressed as 100 minutes for the entire circular map, and adds new genes discovered and established since 1996 and eliminates those shown to correspond to other known genes. The latter are included as synonyms. An alphabetical list of genes showing map location, synonyms, the protein or RNA product of the gene, phenotypes of mutants, and reference citations is provided. In addition to genes known to correspond to gene sequences, other genes, often older, that are described by phenotype and older mapping techniques and that have not been correlated with sequences are included.
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Affiliation(s)
- M K Berlyn
- Department of Biology and School of Forestry and Environmental Studies, Yale University, New Haven, Connecticut 06520-8104, USA.
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43
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Pan YT, Xu B, Rice K, Smith S, Jackson R, Elbein AD. Specificity of the high-mannose recognition site between Enterobacter cloacae pili adhesin and HT-29 cell membranes. Infect Immun 1997; 65:4199-206. [PMID: 9317027 PMCID: PMC175603 DOI: 10.1128/iai.65.10.4199-4206.1997] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Enterobacter cloacae has been implicated as one of the causative agents in neonatal infection and causes a septicemia thought to be initiated via the gastrointestinal tract. The adhesion of radiolabeled E. cloacae to HT-29 cells was concentration and temperature dependent and was effectively blocked by unlabeled bacteria or by millimolar concentrations of alpha-mannosides and micromolar concentrations of high-mannose oligosaccharides. A variety of well-characterized mannose oligosaccharides were tested as inhibitors of adhesion. The best inhibitor was the Man9(GlcNAc)2-tyrosinamide, which was considerably better than other tyrosinamide-linked oligosaccharides such as Man7(GlcNAc)2, Man6(GlcNAc)2 or Man5(GlcNAc)2. Further evidence that the bacteria preferred Man9(GlcNAc)2 structures was obtained by growing HT-29 cells in the presence of glycoprotein processing inhibitors that block mannosidase I and increase the amount of protein-bound Man9(GlcNAc)2 at the cell surface. Such cells bound 1.5- to 2-fold more bacteria than did control cells. The adhesin involved in binding to high-mannose structures was purified from isolated pili. On sodium dodecyl sulfate-gels, a 35-kDa protein was identified by its specific binding to a mannose-containing biotinylated albumin. The amino acid sequences of several peptides from the 35-kDa subunit showed over 85% identity to FimH, the mannose-specific adhesin of Salmonella typhimurium. Pili were labeled with 125I and examined for the ability to bind to HT-29 cells. Binding showed saturation kinetics and was inhibited by the addition of Man9(GlcNAc)2-tyrosinamide but not by oligosaccharides with fewer mannose residues. Polyclonal antibody against this 35-kDa protein also effectively blocked adhesion of pili or E. cloacae, but no effect was observed with nonspecific antibody. These studies demonstrate that the 35-kDa pilus subunit is a lectin whose specificity is directed toward Man, (GlcNAc)2 oligosaccharides.
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MESH Headings
- 1-Deoxynojirimycin/pharmacology
- Adhesins, Bacterial/chemistry
- Adhesins, Bacterial/genetics
- Adhesins, Bacterial/metabolism
- Adhesins, Escherichia coli
- Alkaloids/pharmacology
- Amino Acid Sequence
- Bacterial Adhesion/physiology
- Carbohydrate Sequence
- Cell Membrane/metabolism
- Cells, Cultured
- Enterobacter cloacae/pathogenicity
- Fimbriae Proteins
- Fimbriae, Bacterial/chemistry
- Fimbriae, Bacterial/metabolism
- Indolizines/pharmacology
- Lectins/metabolism
- Lectins, C-Type
- Mannose Receptor
- Mannose-Binding Lectins
- Molecular Sequence Data
- Oligosaccharides/chemistry
- Oligosaccharides/pharmacology
- Peptide Fragments/chemistry
- Protein Binding/drug effects
- Protein Processing, Post-Translational
- Receptors, Cell Surface/antagonists & inhibitors
- Receptors, Cell Surface/metabolism
- Sequence Analysis
- Sequence Homology, Amino Acid
- Swainsonine/pharmacology
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Affiliation(s)
- Y T Pan
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock 72205, USA
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44
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Sokurenko EV, Chesnokova V, Doyle RJ, Hasty DL. Diversity of the Escherichia coli type 1 fimbrial lectin. Differential binding to mannosides and uroepithelial cells. J Biol Chem 1997; 272:17880-6. [PMID: 9211945 DOI: 10.1074/jbc.272.28.17880] [Citation(s) in RCA: 138] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Type 1 fimbriae are the most common adhesive organelles of Escherichia coli. Because of their virtual ubiquity, previous epidemiological studies have not found a correlation between the presence of type 1 fimbriae and urinary tract infections (UTIs). Recently it has become clear that type 1 fimbriae exhibit several different phenotypes, due to allelic variation of the gene for the lectin subunit, FimH, and that these phenotypes are differentially distributed among fecal and UTI isolates. In this study, we have analyzed in more detail the ability of isogenic, recombinant strains of E. coli expressing fimH genes of the predominant fecal and UTI phenotypes to adhere to glycoproteins and to uroepithelial cells. Evidence was obtained to indicate that type 1 fimbriae differ in their ability to recognize various mannosides, utilizing at least two different mechanisms. All FimH subunits studied to date are capable of mediating adhesion via trimannosyl residues, but only certain variants are capable of mediating high levels of adhesion via monomannosyl residues. The ability of the FimH lectins to interact with monomannosyl residues strongly correlates with their ability to mediate E. coli adhesion to uroepithelial cells. In this way, it would be possible for certain phenotypic variants of type 1 fimbriae to contribute more than others to virulence of E. coli in the urinary tract.
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Affiliation(s)
- E V Sokurenko
- Department of Anatomy & Neurobiology, University of Tennessee, Memphis, Tennessee 38163, USA
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45
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Rudin A, Svennerholm AM. Identification of a cross-reactive continuous B-cell epitope in enterotoxigenic Escherichia coli colonization factor antigen I. Infect Immun 1996; 64:4508-13. [PMID: 8890199 PMCID: PMC174405 DOI: 10.1128/iai.64.11.4508-4513.1996] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Enterotoxigenic Escherichia coli (ETEC) colonizes the intestine by means of several antigenically distinct colonization factors (CFs). Several of these CFs have very significant amino acid sequence similarity or identity, particularly in the N-terminal end. We have previously shown that a monoclonal antibody (MAb) raised against the subunits of colonization factor antigen I (CFA/I) fimbriae, which reacts with a peptide corresponding to the 25 N-terminal amino acids of such subunits, can inhibit attachment to intestinal cells of ETEC expressing heterologous as well as homologous CFs, with related amino acid sequences. In this study we have, by means of Pepscan analysis, determined the sequence of the MAb-specific linear epitope to be 15IDLLQ19. Parenteral immunization of rabbits with an N-terminal 25-mer synthetic peptide of CFA/I fimbrial subunit, either covalently coupled to bovine serum albumin or uncoupled, induced high titers of specific antibodies against this peptide as well as against CFA/I fimbriae. Increased titers against several heterologous CF fimbriae with a related N-terminal sequence were also induced, whereas no increase was seen against fimbriae with an unrelated sequence. Neither antisera against the coupled peptide nor antisera against the uncoupled peptide inhibited binding of CF-expressing bacteria to the human intestinal cell line Caco-2 in spite of high titers. The difference in the inhibitory capabilities of the antipeptide sera and the MAb might be due to slightly different epitope specificities. Thus, whereas the antipeptide sera bound to several continuous epitopes in the N-terminal end, none of them reacted specifically with the epitope 15IDLLQ19.
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Affiliation(s)
- A Rudin
- Department of Medical Microbiology and Immunology, Göteborg University, Sweden.
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46
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Mol O, Oudega B. Molecular and structural aspects of fimbriae biosynthesis and assembly in Escherichia coli. FEMS Microbiol Rev 1996; 19:25-52. [PMID: 8916554 DOI: 10.1111/j.1574-6976.1996.tb00252.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Fimbriae are long filamentous polymeric protein structures located at the surface of bacterial cells. They enable the bacteria to bind to specific receptor structures and thereby to colonise specific surfaces. Fimbriae consist of so-called major and minor subunits, which form, in a specific order, the fimbrial structure. In this review emphasis is put on the genetic organisation, regulation and especially on the biosynthesis of fimbriae of enterotoxigenic Escherichia coli strains, and more in particular on K88 and related fimbriae, with ample reference to well-studied P and type 1 fimbriae. The biosynthesis of these fimbriae requires two specific and unique proteins, a periplasmic chaperone and an outer membrane located molecular usher ('doorkeeper'). Molecular and structural aspects of the secretion of fimbrial subunits across the cytoplasmic membrane, the interaction of these subunits with periplasmic molecular chaperone, their translocation to the inner site of the outer membrane and their interaction with the usher protein, as well as the (ordered) translocation of the subunits across the outer membrane and their assembly into a growing fimbrial structure will be described. A model for K88 fimbriae is presented.
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Affiliation(s)
- O Mol
- Department of Molecular Microbiology, IMBW, BioCentrum Amsterdam, Faculty of Biology, The Netherlands
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47
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Wu XR, Sun TT, Medina JJ. In vitro binding of type 1-fimbriated Escherichia coli to uroplakins Ia and Ib: relation to urinary tract infections. Proc Natl Acad Sci U S A 1996; 93:9630-5. [PMID: 8790381 PMCID: PMC38479 DOI: 10.1073/pnas.93.18.9630] [Citation(s) in RCA: 231] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Urinary tract infections, caused mainly by Escherichia coli, are among the most common infectious diseases. Most isolates of the uropathogenic E.coli can express type 1 and P fimbriae containing adhesins that recognize cell receptors. While P fimbriae recognize kidney glycolipid receptors and are involved in peyelonephritis, the urothelial for type 1 fimbriae were not identified. We show that type 1-fimbriated E. coli recognize uroplakins Ia and Ib, two major glycoproteins of urothelial apical plaques. Anchorage of E. coli to urothelial surface via type 1 fimbriae-uroplakin I interactions may play a role in its bladder colonization and eventual ascent through the ureters, against urine flow, to invade the kidneys.
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Affiliation(s)
- X R Wu
- Department of Urology, New York University School of Medicine, NY 10016, USA
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48
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Sokurenko EV, Courtney HS, Maslow J, Siitonen A, Hasty DL. Quantitative differences in adhesiveness of type 1 fimbriated Escherichia coli due to structural differences in fimH genes. J Bacteriol 1995; 177:3680-6. [PMID: 7601831 PMCID: PMC177083 DOI: 10.1128/jb.177.13.3680-3686.1995] [Citation(s) in RCA: 115] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Type 1 fimbriae are heteropolymeric surface organelles responsible for the D-mannose-sensitive (MS) adhesion of Escherichia coli. We recently reported that variation of receptor specificity of type 1 fimbriae can result solely from minor alterations in the structure of the gene for the FimH adhesin subunit. To further study the relationship between allelic variation of the fimH gene and adhesive properties of type 1 fimbriae, the fimH genes from five additional strains were cloned and used to complement the FimH deletion in E. coli KB18. When the parental and recombinant strains were tested for adhesion to immobilized mannan, a wide quantitative range in the ability of bacteria to adhere was noted. The differences in adhesion do not appear to be due to differences in the levels of fimbriation or relative levels of incorporation of FimH, because these parameters were similar in low-adhesion and high-adhesion strains. The nucleotide sequence for each of the fimH genes was determined. Analysis of deduced FimH sequences allowed identification of two sequence homology groups, based on the presence of Asn-70 and Ser-78 or Ser-70 and Asn-78 residues. The consensus sequences for each group conferred very low adhesion activity, and this low-adhesion phenotype predominated among a group of 43 fecal isolates. Strains isolated from a different host niche, the urinary tract, expressed type 1 fimbriae that conferred an increased level of adhesion. The results presented here strongly suggest that the quantitative variations in MS adhesion are due primarily to structural differences in the FimH adhesin. The observed differences in MS adhesion among populations of E. coli isolated from different host niches call attention to the possibility that phenotypic variants of FimH may play a functional role in populations dynamics.
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Affiliation(s)
- E V Sokurenko
- Department of Anatomy and Neurobiology, University of Tennessee, Memphis 38163, USA
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Moureaux N, Karjalainen T, Givaudan A, Bourlioux P, Boemare N. Biochemical Characterization and Agglutinating Properties of Xenorhabdus nematophilus F1 Fimbriae. Appl Environ Microbiol 1995; 61:2707-12. [PMID: 16535079 PMCID: PMC1388497 DOI: 10.1128/aem.61.7.2707-2712.1995] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Xenorhabdus spp., entomopathogenic bacteria symbiotically associated with nematodes of the family Steinernematidae, occur spontaneously in two phases. Only the phase I variants of Xenorhabdus nematophilus F1 expressed fimbriae when the bacteria were grown on a solid medium (nutrient agar; 24 and 48 h of growth). These appendages were purified and characterized. They were rigid, with a diameter of 6.4 (plusmn) 0.3 nm, and were composed of 16-kDa pilin subunits. The latter were synthesized and assembled during the first 24 h of growth. Phase II variants of X. nematophilus did not possess fimbriae and apparently did not synthesize pilin. Phase I variants of X. nematophilus have an agglutinating activity with sheep, rabbit, and human erythrocytes and with hemocytes of the insect Galleria mellonella. The purified fimbriae agglutinated sheep and rabbit erythrocytes. The hemagglutination by bacteria and purified fimbriae was mannose resistant and was inhibited by porcine gastric mucin and N-acetyl-lactosamine. The last sugar seems to be a specific inhibitor of hemagglutination by X. nematophilus.
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Jones CH, Pinkner JS, Roth R, Heuser J, Nicholes AV, Abraham SN, Hultgren SJ. FimH adhesin of type 1 pili is assembled into a fibrillar tip structure in the Enterobacteriaceae. Proc Natl Acad Sci U S A 1995; 92:2081-5. [PMID: 7892228 PMCID: PMC42427 DOI: 10.1073/pnas.92.6.2081] [Citation(s) in RCA: 322] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Type 1 pili are heteropolymeric mannosebinding fibers produced by all members of the Enterobacteriaceae family. The bulk of the fiber is composed of FimA. Two macromolecular complexes responsible for mediating an interaction with mannose-containing receptors were purified from fimA- Escherichia coli by mannose affinity chromatography and ion-exchange chromatography. One complex contained only the mannose-binding adhesin, FimH, associated with FimG, a minor component of the type 1 pilus. In the other complex the FimG-FimH moiety was loosely associated with a chaperone-minor subunit complex (FimC-FimF), possibly representing an intermediate in tip fibrilla assembly. The FimC chaperone has also been shown to form a preassembly complex with FimH that has been purified and characterized previously. Purified FimC did not bind to the FimG-FimH complex but did recognize FimH dissociated from the FimG-FimH complex. Quick-freeze deep-etch electron microscopy revealed that the FimG-FimH complex had a thin fibrillar architecture. High-resolution electron microscopy of type 1 pili revealed that a 16-nm fibrillar tip structure with an architecture identical to that of the FimG-FimH complex was joined end-to-end to the pilus rod. In a fimH- deletion mutant, the tip fibrillae joined to pilus rods were approximately 3 nm in length. The full-length tip fibrilla was restored by complementation with the fimH gene in trans. The bipartite nature of the type 1 pilus was also demonstrated on pili purified from clinical isolates of members of the Enterobacteriaceae family arguing that it is a conserved feature of the type 1 pilus.
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Affiliation(s)
- C H Jones
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO 63110
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