A putative opioid-peptide processing activity in enriched Golgi fraction from rat brain.
A Golgi enriched fraction from rat brain was prepared. The preparation has no carboxypeptidase activity and is not contaminated with cytosol, mitochondria and lysosomes as judged by marker enzyme activities for these constituents. Associated with the Golgi membranes a putative opioid peptide processing activity was demonstrated, which acts on Dynorphin 1-13, alpha- and beta-Neoendorphin. The enzyme cleaves the bond between the paired basic residues, releasing Leucine-enkephalin-Arg6. The activity has a pH-optimum around 9 and is inhibited by serine-protease inhibitors. Intracellular location and substrate specificity suggest that this endopeptidase activity may be involved in proenkephalin processing.
D000595:Amino Acid Sequence; D000818:Animals; D001921:Brain / Q000648:ultrastructure*; D002851:Chromatography, High Pressure Liquid; D010450:Endopeptidases / Q000378:metabolism*; D004723:Endorphins / Q000378:metabolism*; D006056:Golgi Apparatus / Q000201:enzymology*; D006863:Hydrogen-Ion Concentration; D007425:Intracellular Membranes / Q000201:enzymology; D011480:Protease Inhibitors / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D013379:Substrate Specificity
D004723:Endorphins; D011480:Protease Inhibitors; D010450:Endopeptidases