Mechanism of aminoacyl-tRNA acetylation by an aminoacyl-tRNA acetyltransferase AtaT from enterohemorrhagic E. coli.

ABSTRACT: Toxin-antitoxin systems in bacteria contribute to stress adaptation, dormancy, and persistence. AtaT, a type-II toxin in enterohemorrhagic E. coli, reportedly acetylates the α-amino group of the aminoacyl-moiety of initiator Met-tRNAf^Met, thus inhibiting translation initiation. Here, we show that AtaT has a broader specificity for aminoacyl-tRNAs than initially claimed. AtaT efficiently acetylates Gly-tRNA^Gly, Trp-tRNA^Trp, Tyr-tRNA^Tyr and Phe-tRNA^Phe isoacceptors, in addition to Met-tRNAf^Met, and inhibits global translation. AtaT interacts with the acceptor stem of tRNAf^Met, and the consecutive G-C pairs in the bottom-half of the acceptor stem are required for acetylation. Consistently, tRNA^Gly, tRNA

SUBMITTER: Yashiro Y 

PROVIDER: S-EPMC7595197 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature