passages.id: split_5_test_1678_passage
passages.type: progene_text
passages.text: Midpoint reduction potentials for the flavin cofactors in human NADPH - cytochrome P450 oxidoreductase were determined by anaerobic redox titration of the diflavin ( FAD and FMN ) enzyme and by separate titrations of its isolated FAD / NADPH and FMN domains .