A Common Pathway for Activation of Host-Targeting and Bacteria-Targeting Toxins in Human Intestinal Bacteria.

ABSTRACT: Human gut microbes exhibit a spectrum of cooperative and antagonistic interactions with their host and also with other microbes. The major Bacteroides host-targeting virulence factor, Bacteroides fragilis toxin (BFT), is produced as an inactive protoxin by enterotoxigenic B. fragilis strains. BFT is processed by the conserved bacterial cysteine protease fragipain (Fpn), which is also encoded in B. fragilis strains that lack BFT. In this report, we identify a secreted antibacterial protein (fragipain-activated bacteriocin 1 [Fab1]) and its cognate immunity protein (resistance to fragipain-activated bacteriocin 1 [RFab1]) in enterotoxigenic and nontoxigenic strains of B. fragilis. Although BFT and Fab1 share no sequence identity, Fpn also activates the Fab1 protoxin, resulting in its

SUBMITTER: Bao Y 

PROVIDER: S-EPMC8406203 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature