[SCAN] Sensing and processing the interspecies quorum sensing signal AI‐2

Scan Seminar

Title: Sensing and processing the interspecies quorum sensing signal AI‐2

Speaker: Karina Xavier

From: Bacterial Signaling Lab, ITQB

Abstract

Advances in molecular microbiology throughout the past decade have shown that cell-cell communication is the norm in the bacterial world and that bacteria use sophisticated cell-cell signaling mechanisms to regulate gene expression on a population-wide scale. This phenomenon, termed quorum sensing, regulates a wide range of activities in diverse bacteria enabling these organisms to form communities that can benefit from group behaviors similar to higher organisms. Hundreds of species of bacteria have been shown to use quorum sensing systems to regulate processes including antibiotic production, virulence gene expression, and biofilm formation.

Certain bacteria, like Escherichia coli, have a mechanism to sequester and degrade the quorum sensing signals produced by others and thus can interfere with group behaviors of neighboring species. We are studying the molecular mechanisms involved in this process and exploring the possibility of using E. coli as a tool to manipulate inter-species quorum sensing in vivo. We have established a mouse model where we use antibiotics to perturb microbiota composition and E. coli as a tool to manipulate inter-species signaling in the mouse gut. With this model system we will determine how cell-cell interactions mediated by inter-species signaling affect recovery of the microbiota and gut homeostasis.