Diflavin reductase

The differences in structures and redox partners between the two classes of P450 and NOS enzymes give rise to differences in reduction potentials and electron transfer mechanisms. The fusion of the oxygenase domain to its diflavin reductase domain facilitates ET (of relevance here is that P450 BM3 has the highest mono-oxygenase activity of all P450s [56]). 

CPR is the prototype for a small family of diflavin reductases which are believed to have... 

Figure 4.3. Schematic outline of the diflavin reductase family. Members contain an N-terminal FMN-binding flavodoxin-like domain and a C-terminal FAD/NADPH-binding ferredoxin reductase-like domain, which contains an additional linker region. Shown are CPR, which has an amino-terminal membrane anchor region (Anc) NRl (Novel reductase 1) MSR (methionine synthase reductase), which contains an additional inlerdomain sequence P450 BM3, which is fused to a P450 domain and NOS (nitric oxide synthases), which has linked to a heme-containing oxygenase domain that is structurally distinct from the P450s.

Ferredoxin, CPR cytochrome P450 diflavin reductase. Fid flavodoxin, PFOR phthalate-family dioxygenase reductase... 

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