Bacillus subtilis type I antitoxin SR6 explained

SR6 is a 100 nucleotide long antisense RNA antitoxin that overlaps 2 toxins: 3' end of yonT and yoyJ at its 5'end. In type I toxin-antitoxin (TA) systems the antitoxin is a small RNA that neutralizes a toxin protein. Several type I TA systems have been described in B. subtilis.^[1] YonT/SR6 system is located on the SPβ prophage of the B. subtilis chromosome and it was shown to be multi-stress responsive. SR6 acts by promoting yonT mRNA degradation. It may regulate the second toxin, yoyJ by a different mechanism.^[2]

Other B. Subtilis type I TA systems

• txpA/RatA
• bsrG/SR4, bsrE/SR5

Notes and References

1. Durand S, Jahn N, Condon C, Brantl S . Type I toxin-antitoxin systems in Bacillus subtilis . RNA Biology . 9 . 12 . 1491–1497 . December 2012 . 23059907 . 10.4161/rna.22358 . free .
2. Reif C, Löser C, Brantl S . Bacillus subtilis Type I antitoxin SR6 Promotes Degradation of Toxin yonT mRNA and Is Required to Prevent Toxic yoyJ Overexpression . Toxins . 10 . 2 . February 2018 . 74 . 29414903 . 5848175 . 10.3390/toxins10020074 . free .