CBR/b5/P450 Systems
The ubiquitous electron-transport protein cytochrome b5 can serve as an effector (activator or inhibitor) of P450s. It was hypothesized that cytochrome b5 is involved in the transfer of the second electron to P450, either from CPR or from NADH:cytochrome b5 reductase (CBR; EC 1.6.2.2):
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O2 |
| NADH |
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The ability of the CBR/cytochrome b5 system to support P450 catalysis has been demonstrated in vitro using purified CBR and cytochrome b5 from Saccharomyces cerevisiae and CYP51 enzyme from Candida albicans. In this system, both the first and second electrons are donated by CBR.
| NAD(P)H |
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O2 |
Read more about this topic: P450-containing Systems
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