Big endothelin analogues with inhibitory activity on endothelin-converting enzyme-1.
Big endothelin-1 (big ET-1) is converted into an active form, ET-1, by endothelin-converting enzyme-1 (ECE-1). To assess the mechanism of substrate recognition by ECE-1, we examined the effects of variously substituted analogues of big ET-1 on ECE-1 activity, using solubilized membranes prepared from human ECE-1-expressed CHO-K1 cells. Among the big ET-1 analogues tested, [21Phe]big ET-1[18-34] and [31Ala]big ET-1[18-34] exhibited significant inhibition of ECE-1. A kinetic analysis revealed [21Phe]big ET-1[18-34] to be a competitive inhibitor (Ki = 21 microM) and [31Ala]big ET-1[18-34] to be a noncompetitive inhibitor (Ki = 36 microM). These results suggested that ECE-1 recognizes big ET-1 at the P1 position and the C-terminal region in a different manner and that modification of these regions can produce ECE-1 inhibitors.
Takayanagi
R
R
Third Department of Internal Medicine, Faculty of Medicine, Kyushu University, Fukuoka, Japan.
Liu
W
W
Ito
T
T
Ohnaka
K
K
Nawata
H
H
D000818:Animals; D016282:Aspartic Acid Endopeptidases / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D001667:Binding, Competitive / Q000187:drug effects; D016466:CHO Cells; D006224:Cricetinae; D004247:DNA / Q000096:biosynthesis / Q000235:genetics; D019332:Endothelin-1; D000072396:Endothelin-Converting Enzymes; D016232:Endothelins / Q000494:pharmacology*; D006801:Humans; D007700:Kinetics; D008666:Metalloendopeptidases / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D011480:Protease Inhibitors / Q000494:pharmacology*; D011498:Protein Precursors / Q000494:pharmacology*; D013379:Substrate Specificity; D014162:Transfection
D019332:Endothelin-1; D016232:Endothelins; D011480:Protease Inhibitors; D011498:Protein Precursors; D004247:DNA; D016282:Aspartic Acid Endopeptidases; D008666:Metalloendopeptidases; C000606923:ECE1 protein, human; D000072396:Endothelin-Converting Enzymes