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Published on: March 20, 2018
Cytochrome P450 2S1 is reduced by NADPH-cytochrome P450 reductase
Yi Xiao1, Raku Shinkyo, F Peter Guengerich
1Department of Biochemistry and Center in Molecular Toxicology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA.
Abstract:
Cytochrome P450 (P450) 2S1 is one of the orphan P450s without a clear physiological function. Controversy has arisen as to whether it can interact with NADPH-P450 reductase and accept electrons. The reduction of 1,4-bis{[2-(dimethylamino-N-oxide)ethyl]amino}-5,8-dihydroxyanthracene-9,10-dione (AQ4N) by P450 2S1 was confirmed, and the NADPH consumption rates were measured aerobically and anaerobically in the absence and presence of the drug. The reduction kinetics of P450 2S1 were rapid, as measured by stopped-flow kinetics. These results confirm that P450 2S1 can be reduced by NADPH-P450 reductase and suggest normal mixed-function oxidase roles of P450 2S1 to be revealed.
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