NADPH-dependent glutathione peroxidase-like proteins (Gpx-1, Gpx-2) reduce unsaturated fatty acid hydroperoxides in Synechocystis PCC 6803.
Here we isolated and characterized two genes (slr1171, slr1992) designated gpx-1 and gpx-2, respectively, encoding glutathione peroxidase (GPX)-like proteins (Gpx-1, Gpx-2) from Synechocystis PCC 6803. The deduced amino acid sequences for gpx-1 and gpx-2 showed high similarity to those of GPX-like proteins from higher plants and mammalian GPXs, respectively. Surprisingly, both recombinant proteins in Escherichia coli were able to utilize NADPH, but not reduced glutathione, as an electron donor and unsaturated fatty acid hydroperoxides or alkyl hydroperoxides as an acceptor. It seems accurate to refer to Gpx-1 and Gpx-2 as NADPH-dependent GPX-like proteins that serve as a new defense system for the reduction of unsaturated fatty acid hydroperoxides.
Gaber
A
A
Department of Applied Biological Chemistry, Osaka Prefecture University, Sakai, Japan.
Tamoi
M
M
Takeda
T
T
Nakano
Y
Y
Shigeoka
S
S
D000595:Amino Acid Sequence; D003001:Cloning, Molecular; D000458:Cyanobacteria / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000235:genetics; D005231:Fatty Acids, Unsaturated / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D008054:Lipid Peroxides / Q000378:metabolism*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009249:NADP / Q000378:metabolism*; D011994:Recombinant Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D016415:Sequence Alignment; D013379:Substrate Specificity; D000094765:Glutathione Peroxidase GPX1
D005231:Fatty Acids, Unsaturated; D008054:Lipid Peroxides; D011994:Recombinant Proteins; D009249:NADP; D005979:Glutathione Peroxidase; D000094765:Glutathione Peroxidase GPX1