Premium
RsrA, an anti‐sigma factor regulated by redox change
Author(s) -
Kang JuGyeong,
Paget Mark S.B.,
Seok YeongJae,
Hahn MiYoung,
Bae JaeBum,
Hahn JiSook,
Kleanthous Colin,
Buttner Mark J.,
Roe JungHye
Publication year - 1999
Publication title -
the embo journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 7.484
H-Index - 392
eISSN - 1460-2075
pISSN - 0261-4189
DOI - 10.1093/emboj/18.15.4292
Subject(s) - sigma factor , thioredoxin , biology , streptomyces coelicolor , sigma , biochemistry , transcription (linguistics) , redox , transcription factor , rpos , thiol , oxidative stress , microbiology and biotechnology , rna polymerase , chemistry , mutant , promoter , rna , gene expression , gene , linguistics , physics , philosophy , organic chemistry , quantum mechanics
SigR (σ R ) is a sigma factor responsible for inducing the thioredoxin system in response to oxidative stress in the antibiotic‐producing, Gram‐positive bacterium Streptomyces coelicolor A3(2). Here we identify a redox‐sensitive, σ R ‐specific anti‐sigma factor, RsrA, which binds σ R and inhibits σ R ‐directed transcription in vitro only under reducing conditions. Exposure to H 2 O 2 or to the thiol‐specific oxidant diamide caused the dissociation of the σ R –RsrA complex, thereby allowing σ R ‐dependent transcription. This correlated with intramolecular disulfide bond formation in RsrA. Thioredoxin was able to reduce oxidized RsrA, suggesting that σ R , RsrA and the thioredoxin system comprise a novel feedback homeostasis loop that senses and responds to changes in the intracellular thiol–disulfide redox balance.