The function of the chloroplast 2-cysteine peroxiredoxin in peroxide detoxification and its regulation.
The Arabidopsis genome contains nine open reading frames with homology to members of the peroxiredoxin (prx) family: one 1-Cys-prx, two 2-Cys-prx, five type II-prx, and one peroxiredoxin Q. The function of the peroxiredoxins in plant metabolism is only slowly emerging. They are assumed to reduce toxic peroxides to their corresponding alcohols with a rather broad substrate specificity. The 2-Cys peroxiredoxins (2-CP) were recently identified as members of the antioxidant defence system of chloroplasts. Knock-out mutants of Synechocystis and antisense mutants of Arabidopsis have provided insight into the function of 2-CPs in the photosynthetic antioxidant network. This review summarizes present knowledge on the enzymatic mechanism, the physiological context and the genetic regulation of the 2-CPs in plants and cyanobacteria. In addition, an extrapolation on the metabolic role of the chloroplast 2-CP is attempted based on the molecular features of 2-CPs from other organisms.
Dietz
K J
KJ
University of Bielefeld, Department of Plant Physiology and Biochemistry/W5, 33501 Bielefeld, Germany. karl-josef.dietz@biologie.uni-bielefeld.de
Horling
F
F
König
J
J
Baier
M
M
D000975:Antioxidants / Q000378:metabolism; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism* / Q000382:microbiology; D001205:Ascorbic Acid / Q000378:metabolism; D002384:Catalysis; D002736:Chloroplasts / Q000378:metabolism*; D000458:Cyanobacteria / Q000235:genetics / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D008956:Models, Chemical; D010084:Oxidation-Reduction; D010544:Peroxidases / Q000235:genetics / Q000378:metabolism*; D010545:Peroxides / Q000378:metabolism*; D054464:Peroxiredoxins; D010802:Phylogeny; D015398:Signal Transduction
D000975:Antioxidants; D010545:Peroxides; D010544:Peroxidases; D054464:Peroxiredoxins; D001205:Ascorbic Acid