Human peroxiredoxin 5 is a peroxynitrite reductase.
Peroxiredoxins are an ubiquitous family of peroxidases widely distributed among prokaryotes and eukaryotes. Peroxiredoxin 5, which is the last discovered mammalian member, was previously shown to reduce peroxides with the use of reducing equivalents derived from thioredoxin. We report here that human peroxiredoxin 5 is also a peroxynitrite reductase. Analysis of peroxiredoxin 5 mutants, in which each of the cysteine residues was mutated, suggests that the nucleophilic attack on the O-O bond of peroxynitrite is performed by the N-terminal peroxidatic Cys(47). Moreover, with the use of pulse radiolysis, we show that human peroxiredoxin 5 reduces peroxynitrite with an unequalled high rate constant of (7+/-3)x10(7) M(-1)s(-1).
Laboratory of Cell Biology, Institut des Sciences de la Vie, Université catholique de Louvain, 1348 Louvain-la-Neuve, Belgium.
Marlène
M
Dubuisson
Delphine
D
Vander Stricht
André
A
Clippe
Florence
F
Etienne
Thomas
T
Nauser
Reinhard
R
Kissner
Willem H
WH
Koppenol
Jean-François
JF
Rees
Bernard
B
Knoops
D000595:Amino Acid Sequence; D000818:Animals; D006801:Humans; D007448:Invertebrates; D007700:Kinetics; D008322:Mammals; D008969:Molecular Sequence Data; D010088:Oxidoreductases / Q000737:chemistry* / Q000378:metabolism; D010544:Peroxidases / Q000737:chemistry* / Q000378:metabolism; D054464:Peroxiredoxins; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
D010088:Oxidoreductases; D010544:Peroxidases; C515974:PRDX5 protein, human; D054464:Peroxiredoxins; C109110:peroxynitrite reductase