title: The CsoR-like sulfurtransferase repressor (CstR) is a persulfide sensor in Staphylococcus aureus.
abstract: How cells regulate the bioavailability of utilizable sulfur while mitigating the effects of hydrogen sulfide toxicity is poorly understood. CstR [Copper-sensing operon repressor (CsoR)-like sulfurtransferase repressor] represses the expression of the cst operon encoding a putative sulfide oxidation system in Staphylococcus aureus. Here, we show that the cst operon is strongly and transiently induced by cellular sulfide stress in an acute phase and specific response and that cst-encoded genes are necessary to mitigate the effects of sulfide toxicity. Growth defects are most pronounced when S. aureus is cultured in chemically defined media with thiosulfate (TS) as a sole sulfur source, but are also apparent when cystine is used or in rich media. Under TS growth conditions, cells fail to grow as a result of either unregulated expression of the cst operon in a ΔcstR strain or transformation with a non-inducible C31A/C60A CstR that blocks cst induction. This suggests that the cst operon contributes to cellular sulfide homeostasis. Tandem high-resolution mass spectrometry reveals derivatization of CstR by both inorganic tetrasulfide and an organic persulfide, glutathione persulfide, to yield a mixture of Cys31-Cys60' interprotomer cross-links, including di-, tri- and tetrasulfide bonds, which allosterically inhibit cst operator DNA binding by CstR.
authors.affiliation: Department of Chemistry, Indiana University, Bloomington, IN, 47405-7102, USA.
authors.forename: Justin L
authors.initials: JL
authors.lastname: Luebke
authors.forename: Jiangchuan
authors.initials: J
authors.lastname: Shen
authors.forename: Kevin E
authors.initials: KE
authors.lastname: Bruce
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Kehl-Fie
authors.forename: Hui
authors.initials: H
authors.lastname: Peng
authors.forename: Eric P
authors.initials: EP
authors.lastname: Skaar
authors.forename: David P
authors.initials: DP
authors.lastname: Giedroc
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism*; D003300:Copper / Q000378:metabolism; D003470:Culture Media; D015964:Gene Expression Regulation, Bacterial; D006862:Hydrogen Sulfide / Q000494:pharmacology; D009876:Operon; D012097:Repressor Proteins / Q000737:chemistry / Q000378:metabolism*; D013211:Staphylococcus aureus / Q000254:growth & development* / Q000378:metabolism; D013440:Sulfides / Q000378:metabolism*; D053719:Tandem Mass Spectrometry
chemical_list: D001426:Bacterial Proteins; D003470:Culture Media; D012097:Repressor Proteins; D013440:Sulfides; C051552:persulfides; D003300:Copper; D006862:Hydrogen Sulfide