title: Functional characterization of Hsp33 protein from Bacillus psychrosaccharolyticus; additional function of HSP33 on resistance to solvent stress.
abstract: Psychrophiles have been known as efficient organism to degrade organic solvent. To investigate the mechanism of solvent stress and identify the factors that affect the solvent stress in psychrophiles, we selected Bacillus psychrosaccharolyticus one of the psychrophiles and two-dimensional gel electrophoresis was performed. Among the protein spots analyzed by 2-DE, five spots induced in 3% IPA stress conditions were identified by MS/MS, and one of these spots was identified as a Hsp33 family. The Hsp33 protein sequence of B. psychrosaccharolyticus exhibited a high similarity with the corresponding proteins of other bacteria. The Hsp33 protein of B. psychrosaccharolyticus has a highly conserved zinc-binding domain (CXCX, CXXC) that includes four cysteine residues in the C-terminus. In addition, the transcriptional induction of the HSP33 of B. psychrosaccharolyticus was confirmed by Northern blot analysis, and formation of free thiol linkage was induced under stress conditions such as exposure to solvents, heat-shock, and oxidative stress. Furthermore, over-expressed strains of HSP33 of B. psychrosaccharolyticus in Escherichia coli improved stress tolerance to the organic solvent when compared with the wild-type. These data suggest that the solvent stress condition was similar to heat-shock or oxidative stress, especially through the triggering of induction and activation of a redox-regulatory chaperone, Hsp33, and Hsp33 plays a critical role in the tolerance to stress.
authors.affiliation: School of Life Sciences and Biotechnology, Korea University, Anam-dong, Sungbuk-gu, Seoul, Republic of Korea.
authors.forename: Hyun-Jun
authors.initials: HJ
authors.lastname: Kang
authors.forename: Dong-Hyuk
authors.initials: DH
authors.lastname: Heo
authors.forename: So-Woong
authors.initials: SW
authors.lastname: Choi
authors.forename: Kyung-Nam
authors.initials: KN
authors.lastname: Kim
authors.forename: Jaekyung
authors.initials: J
authors.lastname: Shim
authors.forename: Chan-Wha
authors.initials: CW
authors.lastname: Kim
authors.forename: Ha-Chin
authors.initials: HC
authors.lastname: Sung
authors.forename: Cheol-Won
authors.initials: CW
authors.lastname: Yun
mesh_terms: D000595:Amino Acid Sequence; D001407:Bacillus / Q000201:enzymology; D001426:Bacterial Proteins / Q000737:chemistry* / Q000502:physiology; D015180:Electrophoresis, Gel, Two-Dimensional; D004926:Escherichia coli / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000737:chemistry* / Q000502:physiology; D013058:Mass Spectrometry; D018832:Molecular Chaperones / Q000737:chemistry* / Q000502:physiology; D008969:Molecular Sequence Data; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D012313:RNA / Q000737:chemistry; D017386:Sequence Homology, Amino Acid; D012997:Solvents / Q000737:chemistry; D013438:Sulfhydryl Compounds / Q000737:chemistry; D014158:Transcription, Genetic; D015032:Zinc / Q000737:chemistry
chemical_list: D001426:Bacterial Proteins; D006360:Heat-Shock Proteins; D018832:Molecular Chaperones; D012997:Solvents; D013438:Sulfhydryl Compounds; D012313:RNA; D015032:Zinc