Structure and function of NADPH-cytochrome P450 reductase and nitric oxide synthase reductase domain
- Biometal Science Laboratory, RIKEN Harima Institute/Spring8, 1-1-1 Kouto, Mikazuki-cho, Sayo-gun, Hyogo 679-5148 (Japan)
NADPH-cytochrome P450 reductase (CPR) and the nitric oxide synthase (NOS) reductase domains are members of the FAD-FMN family of proteins. The FAD accepts two reducing equivalents from NADPH (dehydrogenase flavin) and FMN acts as a one-electron carrier (flavodoxin-type flavin) for the transfer from NADPH to the heme protein, in which the FMNH {sup {center_dot}}/FMNH{sub 2} couple donates electrons to cytochrome P450 at constant oxidation-reduction potential. Although the interflavin electron transfer between FAD and FMN is not strictly regulated in CPR, electron transfer is activated in neuronal NOS reductase domain upon binding calmodulin (CaM), in which the CaM-bound activated form can function by a similar mechanism to that of CPR. The oxygenated form and spin state of substrate-bound cytochrome P450 in perfused rat liver are also discussed in terms of stepwise one-electron transfer from CPR. This review provides a historical perspective of the microsomal mixed-function oxidases including CPR and P450. In addition, a new model for the redox-linked conformational changes during the catalytic cycle for both CPR and NOS reductase domain is also discussed.
- OSTI ID:
- 20793210
- Journal Information:
- Biochemical and Biophysical Research Communications, Vol. 338, Issue 1; Other Information: DOI: 10.1016/j.bbrc.2005.08.043; PII: S0006-291X(05)01713-4; Copyright (c) 2005 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0006-291X
- Country of Publication:
- United States
- Language:
- English
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