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

Abstract

A cDNA corresponding to a thiol-specifc antioxidant enzyme (TSA) was isolated from a rat brain cDNA library with the use of antibodies to bovine TSA.

Evidence that peroxiredoxins are novel members of the thioredoxin fold superfamily

“…The peroxiredoxin family of enzymes is predicted to contain a domain with a thioredoxin-like fold and with inser- (Chae et al, 1994b: Hudson-Taylor et al, 1995Montemartini et al, 1998) with a structure-based alignment (Holm & Sander, 1998) of Escherichia coli thioredoxin [PDB code: 2TRXl (Katti et al, 1990), Anabaena sp. thioredoxin-2 [ITHX] (Saarinen et al, 1995), bovine glutathione peroxidase [IGPI] (Epp et al, 1983), pig liver glutaredoxin [ IKTE] (Katti et al, 1995), E. coli DsbA [IFVK] (Martin et al, 1993), and E. coli glutaredoxin [IGRX] (Sodano et al, 1991) (ZTRX, ITHX, IGPI, IKTE, IFVK, and IGRX) are colored according to the Prx 75% consensus except for the active site cysteines, colored in magenta (the selenocysteine in lGPl is represented by "C" in italics).…”

“…Prxs (Chae et al, 1994b;Hudson-Taylor et al, 1995;Montemartini et al, 1998;Schr6der et al, 1998). Position-specific iterative BLAST (PSI-BLAST) (Altschul et al, 1997) database searches (using E < 0.001) strongly suggest that Prxs represent a hitherto unknown sixth subclass of the thioredoxin fold-containing enzyme superfamily (for details see Fig.…”

“…Cellular life has evolved a range of ROS-reducing enzymes that regulate the levels of ROS within tissues. These enzymes include catalase, glutathione peroxidase (GPx), and an emerging homologous family of antioxidant enzymes termed the peroxiredoxins (Chae et al, 1994b).…”

“…For the 2-Cys Prxs, the N-terminal conserved cysteine is believed to be oxidized to sulfenic acid during peroxide reduction, and in eukaryotes regeneration of the enzyme in vivo is achieved via a sulfhydryl-reducing enzyme system composed of NADPH, Trx, and Trx reductase (Chae et al, 1994a;Cha & Kim, 1995;Poole, 1996) (consequently many of the eukaryotic 2-Cys Prxs are known as thioredoxin peroxidases). The C-terminal cysteines of 2-Cys TPxs are proposed to be involved in their regulation by Trx (Chae et al, 1994b (Jacobson et al, 1989;Tartaglia et al, 1990;Poole, 1996). Regeneration of the in vivo activities of oxidized 1-Cys TPxs is less clear, although it is likely to depend upon small thiol reducing agents such as cysteine or thioglycerol (Chae et al, 1994a) but not apparently glutathione (Kang et al, 1998a).…”

The plant 2‐Cys peroxiredoxin BAS1 is a nuclear‐encoded chloroplast protein: its expressional regulation, phylogenetic origin, and implications for its specific physiological function in plants

“…Their recent discovery in plants (Baler and Dietz, 1996a,b) shows that 2-Cys peroxiredoxins represent an ubiquitously occurring group of enzymes. For instance, thioredoxindependent peroxide reductases (TPx) have been found in yeast and mammals (Chae et al, 1993(Chae et al, , 1994aKim et al, 1988), subunit C of alkyl hydroperoxide reductase (AhpC) and homologs have been described in various bacteria (for summaries see Baier and Dietz, 1996c;Poole, 1996), and recently basl cDNAs have been reported from Arabidopsis thaliana, barley (Hordeum vulgare) and spinach (Spinacia oleracea) (Baler and Dietz, 1996a,b).…”