Redox Partners: Function Modulators of Bacterial P450 Enzymes.

The superfamily of cytochrome P450 monooxygenases (P450s) is widespread in all kingdoms of life. Functionally versatile P450s are extensively involved in diverse anabolic and catabolic processes. P450s require electrons to be transferred by redox partners (RPs) for O activation and substrate monooxygenation. Unlike monotonic eukaryotic cytochrome P450 reductases, bacterial RP systems are more diverse and complicated. Recent studies have demonstrated that the type, the amount, the combination, and the mode of action of bacterial RPs can affect not only the catalytic rate and product distribution but also the type and selectivity of P450 reactions. These results are leading to a novel opinion that RPs not only function as auxiliary electron transfer proteins but are also important P450 function modulators.