Conversion of big endothelin-1 by membrane-bound metalloendopeptidase in cultured bovine endothelial cells.
We propose a candidate for the "putative" endothelin (ET) converting enzyme in the cultured endothelial cells (ECs) of bovine carotid artery. The enzyme is membrane-bound, soluble in 0.5% Triton X-100, and capable of converting human big ET-1 to ET-1 by a specific cleavage between Trp21 and Val22. The conversion reached 90% after a 5-hr incubation in the presence of DFP, PCMS and pepstatin A, but it was inhibited by EDTA, omicron-phenanthroline or phosphoramidon. The enzyme is very sensitive to pH, and active only between pH 6.6 and pH 7.6. Conversion of big ET-3 by this enzyme was only 1/9 that of big ET-1. From these results, ET-1 converting enzyme in the bovine EC is most likely to be a membrane-bound, neutral metalloendopeptidase, which is much less susceptible to big ET-3.
Okada
K
K
Central Research Laboratories, Banyu Pharmaceutical Co., Ltd., Tokyo, Japan.
Miyazaki
Y
Y
Takada
J
J
Matsuyama
K
K
Yamaki
T
T
Yano
M
M
D000595:Amino Acid Sequence; D000818:Animals; D002339:Carotid Arteries; D002413:Cations, Divalent; D002417:Cattle; D002462:Cell Membrane / Q000201:enzymology; D002478:Cells, Cultured; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D019332:Endothelin-1; D016232:Endothelins / Q000302:isolation & purification / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000201:enzymology*; D007700:Kinetics; D008666:Metalloendopeptidases / Q000378:metabolism*; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000302:isolation & purification; D011480:Protease Inhibitors / Q000494:pharmacology; D011498:Protein Precursors / Q000302:isolation & purification / Q000378:metabolism*; D011863:Radioimmunoassay
D002413:Cations, Divalent; D019332:Endothelin-1; D016232:Endothelins; D010446:Peptide Fragments; D011480:Protease Inhibitors; D011498:Protein Precursors; D008666:Metalloendopeptidases