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Characterization of a dipeptidyl aminopeptidase from bovine adrenal medulla
journal contribution
posted on 2023-05-17, 10:07 authored by Kecorius, E, David SmallDavid Small, Livett, BGAbstract: A dipeptidyl aminopeptidase was partially purified from a supernatant fraction of bovine adrenal medulla by gel filtration and anionâ€exchange chromatography. From gel filtration, the apparent molecular weight of the enzyme was 68,100 and its pH optimum was 9.5. Its Km for hydrolysis of the synthetic substrate arginylarginineâ€Î²â€naphthylamide was 5.5 × 10−6M. The enzyme was inhibited by metal ion chelating agents and thiol blocking agents. suggesting the requirement for both a metal ion and an active cysteine residue for its activity. Several peptides were cleaved by the dipeptidyl aminopeptidase involving the sequential removal of dipeptides from the Nâ€terminus. Biologically active peptides, such as leucineâ€enkephalin, methionineâ€enkephalin, and angiotensin II, were hydrolyzed by the dipeptidyl aminopeptidase although opioid peptides with a length greater than five amino acid residues were not susceptible to hydrolysis. Other peptides with a blocked Nâ€terminus (neurotensin, bombesin) or a proline residue adjacent to a potential cleavage site (substance P) were not hydrolyzed. The ability of this dipeptidyl aminopeptidase to degrade certain neuropeptides suggests that it could be involved in neuropeptide degradation. Copyright © 1988, Wiley Blackwell. All rights reserved
History
Publication title
Journal of NeurochemistryVolume
50Pagination
38-44ISSN
0022-3042Department/School
Menzies Institute for Medical ResearchPublisher
Blackwell Publishing LtdPlace of publication
9600 Garsington Rd, Oxford, England, Oxon, Ox4 2DgRights statement
The definitive published version is available online at: http://www3.interscience.wiley.com/Repository Status
- Restricted