title: Bacillus subtilis paraquat resistance is directed by sigmaM, an extracytoplasmic function sigma factor, and is conferred by YqjL and BcrC.
abstract: A Bacillus subtilis sigM null mutant, lacking the extracytoplasmic function sigma(M) protein, was sensitive to paraquat (PQ), a superoxide-generating reagent, but not to the redox stress-inducing compounds hydrogen peroxide, cumene hydroperoxide, t-butyl hydroperoxide, or diamide. Surprisingly, a sigM mutant was only sensitive to superoxide-generating compounds with a dipyridyl ring such as PQ, ethyl viologen, benzyl viologen, and diquat but not to menadione, plumbagin, pyrogallol, or nitrofurantoin. Mutational analysis of candidate sigma(M)-regulated genes revealed that both YqjL, a putative hydrolase, and BcrC, a bacitracin resistance protein, were involved in PQ resistance. Expression of yqjL, but not bcrC, from a xylose-inducible promoter restored PQ resistance to the sigM mutant.
authors.affiliation: Department of Microbiology, Cornell University, Ithaca, NY 14853-8101, USA.
authors.forename: Min
authors.initials: M
authors.lastname: Cao
authors.forename: Charles M
authors.initials: CM
authors.lastname: Moore
authors.forename: John D
authors.initials: JD
authors.lastname: Helmann
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000502:physiology*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001412:Bacillus subtilis / Q000187:drug effects* / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics / Q000502:physiology*; D001555:Benzene Derivatives / Q000494:pharmacology; D004252:DNA Mutational Analysis; D003958:Diamide / Q000494:pharmacology; D004178:Diquat / Q000494:pharmacology; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D006861:Hydrogen Peroxide / Q000494:pharmacology; D006867:Hydrolases / Q000235:genetics / Q000502:physiology*; D009154:Mutation; D009285:Naphthoquinones / Q000494:pharmacology; D009582:Nitrofurantoin / Q000494:pharmacology; D010269:Paraquat / Q000494:pharmacology*; D011748:Pyrogallol / Q000494:pharmacology; D012808:Sigma Factor / Q000235:genetics / Q000502:physiology*; D014755:Viologens / Q000494:pharmacology; D024483:Vitamin K 3 / Q000494:pharmacology; D020122:tert-Butylhydroperoxide / Q000494:pharmacology
chemical_list: D018528:ATP-Binding Cassette Transporters; D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D001555:Benzene Derivatives; D009285:Naphthoquinones; D012808:Sigma Factor; D014755:Viologens; C121796:bacitracin permease; D011748:Pyrogallol; D003958:Diamide; D024483:Vitamin K 3; D009582:Nitrofurantoin; D020122:tert-Butylhydroperoxide; D004178:Diquat; D006861:Hydrogen Peroxide; D006867:Hydrolases; C007164:cumene hydroperoxide; D010269:Paraquat; C014758:plumbagin