Diversification of Type VI Secretion System Toxins Reveals Ancient Antagonism among Bee Gut Microbes.

ABSTRACT: Microbial communities are shaped by interactions among their constituent members. Some Gram-negative bacteria employ type VI secretion systems (T6SSs) to inject protein toxins into neighboring cells. These interactions have been theorized to affect the composition of host-associated microbiomes, but the role of T6SSs in the evolution of gut communities is not well understood. We report the discovery of two T6SSs and numerous T6SS-associated Rhs toxins within the gut bacteria of honey bees and bumble bees. We sequenced the genomes of 28 strains of Snodgrassella alvi, a characteristic bee gut microbe, and found tremendous variability in their Rhs toxin complements: altogether, these strains appear to encode hundreds of unique toxins. Some toxins are shared with Gilliamella apicola<

SUBMITTER: Steele MI 

PROVIDER: S-EPMC5727410 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature