Role of PemI in the Staphylococcus aureus PemIK toxin-antitoxin complex: PemI controls PemK by acting as a PemK loop mimic.

ABSTRACT: Staphylococcus aureus is a notorious and globally distributed pathogenic bacterium. New strategies to develop novel antibiotics based on intrinsic bacterial toxin-antitoxin (TA) systems have been recently reported. Because TA systems are present only in bacteria and not in humans, these distinctive systems are attractive targets for developing antibiotics with new modes of action. S. aureus PemIK is a type II TA system, comprising the toxin protein PemK and the labile antitoxin protein PemI. Here, we determined the crystal structures of both PemK and the PemIK complex, in which PemK is neutralized by PemI. Our biochemical approaches, including fluorescence quenching and polarization assays, identified Glu20, Arg25, Thr48, Thr49, and Arg84 of PemK as being important for RNase function. Our

SUBMITTER: Kim DH 

PROVIDER: S-EPMC8887465 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature