L-ornithine N5 monooxygenase (EC 1.14.13.195 or EC 1.14.13.196) is an enzyme which catalyzes one of the following chemical reactions: L-ornithine + NADPH + O2 N(5)-hydroxy-L-ornithine + NADP+ + H2OL-ornithine + NAD(P)H + O2 N(5)-hydroxy-L-ornithine + NAD(P)+ + H2O The three ligands of this enzyme are L-ornithine (substrate), FAD (cofactor), and NADPH or NAD(P)H (cofactor and electron donor).