[An enzyme that utilizes NADH or NADPH to reduce FLAVINS. It is involved in a number of biological processes that require reduced flavin for their functions such as bacterial bioluminescence. Formerly listed as EC 1.6.8.1 ( MSH )] (UMLS (CSP) C0068341) =Amino Acid, Peptide, or Protein; Enzyme ; =iron sulfur protein; NAD(P)H oxidoreductase; respiratory enzyme;