Bacillus subtilis Type I antitoxin SR6 Promotes Degradation of Toxin yonT mRNA and Is Required to Prevent Toxic yoyJ Overexpression.

ABSTRACT: yonT/SR6 is the second type I toxin-antitoxin (TA) system encoded on prophage SPβ in the B. subtilis chromosome. The yonT ORF specifying a 58 aa toxin is transcribed on a polycistronic mRNA under control of the yonT promoter. The antitoxin SR6 is a 100 nt antisense RNA that overlaps yonT at its 3' end and the downstream gene yoyJ encoding a second, much weaker, toxin at its 5' end. SR6 displays a half-life of >60 min, whereas yonT mRNA is less stable with a half-life of ≈8 min. SR6 is in significant excess over yonT mRNA except in minimal medium with glucose. It interacts with the 3' UTR of yonT mRNA, thereby promoting its degradation by RNase III. By contrast, SR6 does not affect the amount or half-life of yoyJ mRNA. However, in its absence, a yoyJ overexpression plasmid could not be esta

SUBMITTER: Reif C 

PROVIDER: S-EPMC5848175 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature