Proteolysis of endomorphin-1 by brain synaptic membrane-associated peptidases.
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.
Wu
Liming
L
Pharmaceutic Biotechnology Key Laboratory, Nanjing University, Nanjing 210093, P. R. China.
Chen
Junhui
J
Zhong
Dulai
D
Lin
Chentao
C
Wang
Xingchang
X
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
D009842:Oligopeptides; D010446:Peptide Fragments; D010940:Plant Proteins; D011480:Protease Inhibitors; C105293:endomorphin 1; D010447:Peptide Hydrolases