Helicobacter pylori: A chameleon-like approach to life

Abstract

Helicobacter pylori (H. pylori) is widely adaptable for colonization in human stomachs in more than half of the world’s population. The microorganism is characterized by an unusual capability of arranging itself in both genotypic and phenotypic ways. Stressing conditions, including antimicrobial agents in sub-inhibitory concentrations, facilitate entering the viable but nonculturable state in which bacterial cells acquire the coccoid form. This morphotype represents an important strategy for bacterial survival in unsuitable conditions and also allows escape from the immune system. H. pylori is capable of forming biofilm outside and inside the host. For the bacterial population, the sessile growth mode represents an ideal environment for gene rearrangement, as it allows the acquiring of important tools aimed to improve bacterial “fitness” and species preservation. Biofilm formation in H. pylori in the human host also leads to recalcitrance to antibiotic treatment, thus hampering eradication. These lifestyle changes of H. pylori allow for a “safe haven” for its survival and persistence according to different ecological niches, and strongly emphasize the need for careful H. pylori surveillance to improve management of the infection.

Keywords: Helicobacter pylori; Viable But Non Culturable state; Route of transmission; Biofilm in vitro; Biofilm in vivo

Core tip:Helicobacter pylori (H. pylori) is a Gram negative bacterium that colonizes the human stomach early in the life of the host and tends to persist. The present review is focused on the general phenomenon of the fickleness in H. pylori and analyses the significance and role of this “chameleon-like” approach to life in the persistence of this fastidious bacterium outside and inside the host.