Inactivation of monoamine oxidase B by 1-phenylcyclopropylamine: mass spectral evidence for the flavin adduct

Incubation of 1-phenylcyclopropylamine with bovine liver MAO (MAO B), followed by complete enzymatic digestion to single amino acid residues and subsequent analysis by on-line liquid chromatography–electrospray ionization mass spectrometry, was used to investigate the resulting flavin adduct structure.