title: Bacterial scavengase p20 is structurally and functionally related to peroxiredoxins.
abstract: Scavengase p20 was recently identified as a novel family of bacterial antioxidant enzymes possessing thioredoxin-linked thiol peroxidase activity. In this study, the Escherichia coli gene coding for scavengase p20 was isolated from three different strains and the nucleotide sequence was determined. Multiple alignment of amino acid sequence revealed that a previously unidentified Cys-61 is most conserved among all bacterial p20 scavengases and corresponds to the active site in the well-characterized peroxiredoxins. Phylogenetic analysis further supported that scavengase p20 is a novel subfamily of peroxiredoxins. Site-directed mutagenesis studies demonstrated that Cys-61 is indispensable for the antioxidant activities of scavengase p20. Taken together, our findings strongly suggest that the p20 scavengases are structurally and functionally related to peroxiredoxins.
authors.affiliation: National Key Laboratory of Molecular Biology and Genetic Engineering, Chinese Academy of Preventive Medicine, Beijing, People's Republic of China.
authors.forename: Y
authors.initials: Y
authors.lastname: Zhou
authors.forename: X Y
authors.initials: XY
authors.lastname: Wan
authors.forename: H L
authors.initials: HL
authors.lastname: Wang
authors.forename: Z Y
authors.initials: ZY
authors.lastname: Yan
authors.forename: Y D
authors.initials: YD
authors.lastname: Hou
authors.forename: D Y
authors.initials: DY
authors.lastname: Jin
mesh_terms: D000595:Amino Acid Sequence; D000975:Antioxidants / Q000737:chemistry / Q000378:metabolism*; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D003001:Cloning, Molecular; D017124:Conserved Sequence; D017931:DNA Primers / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D029968:Escherichia coli Proteins; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D015394:Molecular Structure; D016297:Mutagenesis, Site-Directed; D033903:Periplasmic Proteins; D010544:Peroxidases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D010802:Phylogeny; D017386:Sequence Homology, Amino Acid
chemical_list: D000975:Antioxidants; D017931:DNA Primers; D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; D033903:Periplasmic Proteins; D010544:Peroxidases; C097049:Tpx protein, E coli