title: YlaC is an extracytoplasmic function (ECF) sigma factor contributing to hydrogen peroxide resistance in Bacillus subtilis.
abstract: In this study, we have attempted to characterize the functions of YlaC and YlaD encoded by ylaC and ylaD genes in Bacillus subtilis. The GUS reporter gene, driven by the yla operon promoter, was expressed primarily during the late exponential and early stationary phase, and its expression increased as the result of hydrogen peroxide treatment. Northern and Western blot analyses revealed that the level of ylaC transcripts and YlaC increased as the result of challenge with hydrogen peroxide. A YlaC-overexpressing strain evidenced hydrogen peroxide resistance and a three-fold higher peroxidase activity as compared with a deletion mutant. YlaC-overexpressing and YlaD-disrupted strains evidenced higher sporulation rates than were observed in the YlaC-disrupted and YlaD-overexpressing strains. Analyses of the results of native polyacrylamide gel electrophoresis of recombinant YlaC and YlaD indicated that interaction between YlaC and YlaD was regulated by the redox state of YlaD in vitro. Collectively, the results of this study appear to suggest that YlaC regulated by the YlaD redox state, contribute to oxidative stress resistance in B. subtilis.
authors.affiliation: School of Biological Sciences, Institute of Microbiology, Seoul National University, Seoul 151-742, Republic of Korea.
authors.forename: Han-Bong
authors.initials: HB
authors.lastname: Ryu
authors.forename: Inji
authors.initials: I
authors.lastname: Shin
authors.forename: Hyung-Soon
authors.initials: HS
authors.lastname: Yim
authors.forename: Sa-Ouk
authors.initials: SO
authors.lastname: Kang
mesh_terms: D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D003001:Cloning, Molecular; D003593:Cytoplasm / Q000378:metabolism; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D017930:Genes, Reporter; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction; D018384:Oxidative Stress / Q000235:genetics; D009195:Peroxidase / Q000235:genetics* / Q000378:metabolism; D012808:Sigma Factor / Q000235:genetics / Q000378:metabolism*; D013171:Spores, Bacterial / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D001426:Bacterial Proteins; D012808:Sigma Factor; D006861:Hydrogen Peroxide; D009195:Peroxidase