Oxidoreductase FAD-binding domain explained

The oxidoreductase FAD-binding domain is an evolutionary conserved protein domain. To date, the 3D-structures of the flavoprotein domain of Zea mays nitrate reductase^[1] and of pig NADH:cytochrome b5 reductase^[2] have been solved. The overall fold is similar to that of ferredoxin:NADP⁺ reductase:^[3] the FAD-binding domain (N-terminal) has the topology of an anti-parallel beta-barrel, while the NAD(P)-binding domain (C-terminal) has the topology of a classical pyridine dinucleotide-binding fold (i.e. a central parallel beta-sheet flanked by 2 helices on each side).

Examples

Human genes encoding proteins containing this domain include:

• CYB5R1; CYB5R2; CYB5R4; CYB5RL;

Notes and References

1. Lindqvist Y, Schneider G, Campbell WH, Lu G . Crystal structure of the FAD-containing fragment of corn nitrate reductase at 2.5 A resolution: relationship to other flavoprotein reductases . Structure . 2 . 9 . 809–821 . 1994 . 7812715 . 10.1016/s0969-2126(94)00082-4. free .
2. Miki K, Nishida H, Inaka K, Yamanaka M, Kaida S, Kobayashi K . Crystal structure of NADH-cytochrome b5 reductase from pig liver at 2.4 A resolution . Biochemistry . 34 . 9 . 2763–2767 . 1995 . 7893687 . 10.1021/bi00009a004.
3. Karplus PA, Bruns CM . Structure-function relations for ferredoxin reductase . J. Bioenerg. Biomembr. . 26 . 1 . 89–99 . 1994 . 8027025 . 10.1007/BF00763221. 1004663 .