title: Proteolysis of endomorphin-1 by brain synaptic membrane-associated peptidases.
abstract: The biotransformation of endomorphin-1 (EM-1) by brain synaptic membranes has been studied. Peptide fragments of EM-1 that were formed during incubation with membrane preparations in vitro were isolated by High-performance liquid chromatography (HPLC) and characterized using determination of amino acid composition. At pH 7.4, two degradation products, EM-1(1-3) and EM-1(1-2), were identified. EM-1 was degraded 77.5% at 30 min incubation with synaptic membranes. The time course of the experiments and the effect of carboxypeptidase inhibitor (CPI) demonstrated that the proteolysis reaction involves the participation of carboxypeptidase activity.
authors: Pharmaceutic Biotechnology Key Laboratory, Nanjing University, Nanjing 210093, P. R. China.
authors: Liming
authors: L
authors: Wu
authors: Junhui
authors: J
authors: Chen
authors: Dulai
authors: D
authors: Zhong
authors: Chentao
authors: C
authors: Lin
authors: Xingchang
authors: X
authors: Wang
mesh_terms: D000595:Amino Acid Sequence / Q000235:genetics; D000818:Animals; D001921:Brain / Q000378:metabolism*; D005260:Female; D008297:Male; D051379:Mice; D009842:Oligopeptides / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D010446:Peptide Fragments / Q000235:genetics / Q000302:isolation & purification; D010447:Peptide Hydrolases / Q000378:metabolism*; D010940:Plant Proteins / Q000494:pharmacology; D011480:Protease Inhibitors / Q000494:pharmacology; D013570:Synaptic Membranes / Q000378:metabolism*; D013997:Time Factors
chemical_list: D009842:Oligopeptides; D010446:Peptide Fragments; D010940:Plant Proteins; D011480:Protease Inhibitors; C105293:endomorphin 1; D010447:Peptide Hydrolases