Crystal structures have been determined for yeast (Schizosaccharomyces pombe)<unk>  ( PDB: 1VQW) and bacterial (Methylophaga aminisulfidivorans)<unk>  ( PDB: 2XVH). The crystal structures are similar to each other and they share 27% sequence identity. These enzymes share 22% and 31% sequence identity with human<unk> s, respectively. Channel and active site of bacterial<unk>  with bound NADPH and FAD ( PDB: 2XVH).<unk> s have a tightly bound FAD prosthetic group and a binding NADPH cofactor. Both dinucleotide binding motifs form Rossmann folds. The yeast<unk>  and bacterial<unk>  are dimers, with each monomer consisting of two structural domains: the smaller NADPH binding domain and the larger FAD-binding domain. The two domains are connected by a double linker. A channel between the two domains leads to the active site where NADPH binds both domains and occupies a cleft that blocks access to the<unk>  group of FAD, which is bound to the large domain along the channel together with a water molecule. The nicotinamide group of NADPH interacts with the<unk>  group of FAD, and the NADPH binding site overlaps with the substrate binding site on the<unk>  group.<unk> s contain several sequence motifs that are conserved across all domains: * FAD-binding motif (GXGXXG) *<unk>  identifying motif (FXGXXXHXXXF/Y) * NADPH-binding motif (GXSXXA) * F/LATGY motif * arginine residue in the active site The<unk>  identifying motif interacts with the<unk>  of FAD. The F/LATGY motif is a sequence motif common in N-hydroxylating enzymes. The arginine residue interacts with the phosphate group of NADPH.
Flavin-containing monooxygenase
Flavin containing monooxygenase 1
Biotinidase
Disaccharidase
Transfer factor
Proteases 
Amidase
Xanthine oxidase