Microbiome, Probiotics & Gut Nutrition

Biography

Biography: Pratibha Gurung

Abstract

Enterococcus faecalis, a Gram-positive bacteria inhabiting the human gut, poses a formidable challenge as an opportunistic pathogen due to its capacity to develop antimicrobial resistance and form biofilms. Overcoming the host immune response, including lysozyme-induced killing, is a critical aspect of its pathogenicity. E. faecalis cells become more susceptible to lysozyme when the gene encoding the site 2 membrane metalloprotease Eep is disrupted. LiaX, a protein with adhesin and antimicrobial sensing properties, is a key component of the LiaFSR system responsible for sensing and responding to environmental stressors. We found that deletion of liaX in the Δeep background represses the loss of eep-dependent lysozyme resistance, implicating that liaX contributes to the conferral of lysozyme resistance. We hypothesize that deletion of liaX in the Δeep background restores lysozyme resistance by remodeling the cell membrane and modifying cell surface net charge. In support of this hypothesis, the Δeep ΔliaX strain has increased sensitivity to membrane-targeting detergents and the cationic antimicrobial polymyxin B. Understanding the mechanisms of lysozyme resistance and biofilm formation is important for developing targeted strategies against E. faecalis infections. The identification of liaX as a pivotal player in these processes opens up novel avenues for interventions, such as disrupting biofilm formation and mitigating antibiotic resistance. Furthermore, recent studies showing the conservation and functional significance of liaX across different bacterial pathogens highlights the potential application of our research in understanding antimicrobial resistance mechanisms and designing targeted therapies in other bacteria as well.