Bile Salts Modulate the Mucin-Activated Type VI Secretion System of Pandemic Vibrio Cholerae

Overview

Journal PLoS Negl Trop Dis

Specialties Infectious Diseases
Tropical Medicine

Date 2015 Aug 29

PMID 26317760

Citations 62

Authors

Verena Bachmann

Benjamin Kostiuk

Daniel Unterweger

Laura Diaz-Satizabal

Stephen Ogg

Stefan Pukatzki

Affiliations

Soon will be listed here.

Abstract

The causative agent of cholera, Vibrio cholerae, regulates its diverse virulence factors to thrive in the human small intestine and environmental reservoirs. Among this pathogen's arsenal of virulence factors is the tightly regulated type VI secretion system (T6SS). This system acts as an inverted bacteriophage to inject toxins into competing bacteria and eukaryotic phagocytes. V. cholerae strains responsible for the current 7th pandemic activate their T6SS within the host. We established that T6SS-mediated competition occurs upon T6SS activation in the infant mouse, and that this system is functional under anaerobic conditions. When investigating the intestinal host factors mucins (a glycoprotein component of mucus) and bile for potential regulatory roles in controlling the T6SS, we discovered that once mucins activate the T6SS, bile acids can further modulate T6SS activity. Microbiota modify bile acids to inhibit T6SS-mediated killing of commensal bacteria. This interplay is a novel interaction between commensal bacteria, host factors, and the V. cholerae T6SS, showing an active host role in infection.

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