A broadly distributed toxin family mediates contact-dependent antagonism between gram-positive bacteria
Abstract
The Firmicutes are a phylum of bacteria that dominate numerous polymicrobial habitats of importance to human health and industry. Although these communities are often densely colonized, a broadly distributed contact-dependent mechanism of interbacterial antagonism utilized by Firmicutes has not been elucidated. Here we show that proteins belonging to the LXG polymorphic toxin family present in Streptococcus intermedius mediate cell contact- and Esx secretion pathway-dependent growth inhibition of diverse Firmicute species. The structure of one such toxin revealed a previously unobserved protein fold that we demonstrate directs the degradation of a uniquely bacterial molecule required for cell wall biosynthesis, lipid II. Consistent with our functional data linking LXG toxins to interbacterial interactions in S. intermedius, we show that LXG genes are prevalent in the human gut microbiome, a polymicrobial community dominated by Firmicutes. We speculate that interbacterial antagonism mediated by LXG toxins plays a critical role in shaping Firmicute-rich bacterial communities.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jul 11, 2017
- Source ID
- 10.7554/elife.26938
Entities
People
- Adrian J Verster
- Diane Bryant
- Elhanan Borenstein
- Hemantha D Kulasekara
- John C Whitney
- Joseph D. Mougous
- Jungyun Kim
- Manuel Pazos
- Mary Q Ching
- Matthew C. Radey
- Michael G. Surette
- Nathan P Bullen
- Snow Peterson
- Waldemar Vollmer
- Young Ah Goo
Organizations
- Burroughs Wellcome Fund
- Canadian Institutes of Health Research
- Defense Threat Reduction Agency
- Howard Hughes Medical Institute
- McMaster University
- Medical Research Council
- National Cancer Institute
- National Institutes of Health
- Natural Sciences and Engineering Research Council
- Newcastle University
- Northwestern University
- Santa Fe Institute
- University of Washington