The hydrolysis of endothelins by neutral endopeptidase 24.11 (enkephalinase)

• Published in: The Journal of biological chemistry Vol. 265; no. 24; pp. 14150 - 14155
• Main Authors: VIJAYARAGHAVAN, J, SCICLI, A. G, CARRETERO, O. A, SLAUGHTER, C, MOOMAW, C, HERSH, L. B
• Format: Journal Article
• Language: English
• Published: Bethesda, MD American Society for Biochemistry and Molecular Biology 25-08-1990
• Subjects: Amino Acid Sequence; Analytical, structural and metabolic biochemistry; Animals; Biological and medical sciences; Chromatography, High Pressure Liquid; endothelin; Endothelins; Endothelium, Vascular; Enzymes and enzyme inhibitors; Fundamental and applied biological sciences. Psychology; Hydrolases; Hydrolysis; Kidney - enzymology; Kinetics; Molecular Sequence Data; Neprilysin - isolation & purification; Neprilysin - metabolism; Peptide Fragments - isolation & purification; Peptides - metabolism; Rats; Substrate Specificity; Thermolysin - metabolism; Endothelin; Rat; Rodentia; Peptide hormone; HPLC chromatography; Kidney; Membrane metallo-endopeptidase; Vertebrata; Mammalia; Enzymatic digestion; Vasoconstrictor agent; Kinetics; Mechanism of action
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1016/S0021-9258(18)77280-3

Endothelins 1-3 are a family of 21-amino acid peptides whose structure consists of two rings formed by intra-chain disulfide
bonds and a linear "COOH-terminal tail." These peptides were originally described on the basis of their potent vasoconstrictor
activity. The hydrolytic inactivation of endothelin action has recently been implicated to be attributed, at least in part,
to the enzyme neutral endopeptidase 24.11 (Scicli, A. G., Vijayaraghavan, J., Hersh, L., and Carretero, O. (1989) Hypertension
14, 353). The kinetic properties and mode of hydrolysis of the endothelins by this enzyme are reported in this study. The
Km for endothelins 1 and 3 hydrolysis is approximately 2 microM while endothelin2 exhibits a 5-fold higher Km. Endothelins
1 and 2 exhibit similar Vmax values while endothelin3 is hydrolyzed considerably more slowly. The initial cleavage site in
endothelin1 is at the Ser5-Leu6 bond located within one of the cyclic structures. Thermolysin, a bacterial neutral endopeptidase
with a similar substrate specificity to neutral endopeptidase 24.11 initially cleaves endothelin1 between His16-Leu17 which
lies within the COOH-terminal linear "tail" portion of the molecule. The cleavage of endothelins 2 and 3 by neutral endopeptidase
24.11 differs from that observed with endothelin1 in that cleavage of these endothelins occurs at Asp18-Ile19 within the linear
COOH-terminal tail structure. These results demonstrate that the endothelins are good substrates for neutral endopeptidase
24.11 and suggest that their mode of cleavage is dependent upon both amino acid sequence as well as peptide conformation.