Cloning and sequencing of thiol-specific antioxidant from mammalian brain: alkyl hydroperoxide reductase and thiol-specific antioxidant define a large family of antioxidant enzymes.

摘要: A cDNA corresponding to a thiol-specific antioxidant enzyme (TSA) was isolated from rat brain library with the use of antibodies bovine TSA. The clone encoded an open reading frame capable encoding 198-residue polypeptide. and yeast TSA proteins show significant sequence homology 21-kDa component (AhpC) Salmonella typhimurium alkyl hydroperoxide reductase, we have found that AhpC exhibits activity. define family > 25 different present in organisms all kingdoms. similarity among members extends over entire ranges between 23% 98% identity. majority AhpC/TSA contain two conserved cysteines. At least eight genes AhpC/TSA-like polypeptides are proximity other oxidoreductase activities, expression several homologs has been correlated pathogenicity. We suggest represents widely distributed class enzymes. also report second proteins, defined by 57-kDa (AhpF) reductase thioredoxin expanded include six additional members.