title: Characterization of an aminopeptidase in cerebrospinal fluid. Structure elucidation of enzyme hydrolysis products of synthetic methionine-enkephalin by reversed-phase high-performance liquid chromatography and mass spectrometry.
abstract: An aminopeptidase was found in canine cerebrospinal fluid via the presence of two products: Y, which has an [M + H]+ ion at m/z 182; and GGFM, which has an [M + H]+ ion at m/z 411. The linked scan at a constant ratio of the magnetic field to the electric field of the GGFM [M + H]+ ion at m/z 411 generates product ions at m/z 120, 150, 266, 297, 354, 357, and 411. That aminopeptidase was bestatin-sensitive (BSAP = bestatin-sensitive aminopeptidase), and had a half-time for disappearance of 60 min, maximum velocity of 1.08 nmol ml-1 min-1, and Michaelis constant of 0.26 nM.
authors.affiliation: Charles B. Stout Neuroscience Mass Spectrometry Laboratory, University of Tennessee, Memphis 38163.
authors.forename: J J
authors.initials: JJ
authors.lastname: Kusmierz
authors.forename: D M
authors.initials: DM
authors.lastname: Desiderio
mesh_terms: D000626:Aminopeptidases / Q000134:cerebrospinal fluid*; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D004285:Dogs; D004744:Enkephalin, Methionine / Q000378:metabolism*; D006868:Hydrolysis; D007700:Kinetics; D013058:Mass Spectrometry
chemical_list: D004744:Enkephalin, Methionine; D000626:Aminopeptidases