Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P20366 (substance P)
 21,176 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cultured bovine pulmonary artery endothelial cells contain a second peptidyl dipeptidase, distinct from angiotensin-converting enzyme, present in an inactive form associated with a non-dialyzable inhibitor. Partial purification by glycine affinity chromatography separates enzyme from inhibitor to yield a preparation which hydrolyzes angiotensin-1, bradykinin, substance P, atriopeptin-2, enkephalin and Hip-His-Leu. This enzyme is resistant to inhibition by lisinopril, captopril, thiorphan, phosphoramidon, soybean trypsin inhibitor, PMSF and aminopeptidase and carboxypeptidase inhibitors, but is inhibited by EDTA.
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PMID:Conversion of angiotensin-1 to angiotensin-2 by a latent endothelial cell peptidyl dipeptidase that is not angiotensin-converting enzyme. 351 10

We have studied inhibition of purified canine angiotensin converting enzyme by substance P and its nonapeptide derivative using Hip-His-Leu as the substrate. Kinetic studies indicated that both substance P and its nonapeptide derivative inhibited the hydrolysis of Hip-His-Leu at different concentrations. The mode of inhibition was competitive with a Ki of 1.15 microM for substance P. These results indicate that substance P is a potent inhibitor of angiotensin converting enzyme in vitro.
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PMID:Inhibition of canine lung angiotensin converting enzyme by substance P. 618 2

Angiotensin I-converting enzyme (ACE, E.C.3.4.15.1) has been recently shown to contain two very similar domains, each of which bears a functional active site hydrolyzing Hip-His-Leu or angiotensin I (AI). The substrate specificity of the two active sites of ACE was compared using wild-type recombinant ACE and mutants, where one active site is suppressed by deletion or inactivated by mutations of 2 histidines coordinating an essential zinc atom. Both active sites converted bradykinin (BK) to BK1-7 and BK1-5 with similar kinetics and with Kappm at least 30 times lower and kcat/kappm 10 times higher than for AI. The carboxyl-terminal active site, but not the amino-terminal site, was activated by chloride; however, chloride activation was minimal compared with AI. Both domains also hydrolyzed substance P and cleaved a carboxyl-terminal protected dipeptide and tripeptide. The carboxyl-terminal active site was more readily activated by chloride and hydrolyzed substance P faster. Luteinizing-hormone releasing hormone was hydrolyzed by both active sites, but hydrolysis by the amino-terminal active site was faster. It performed the endoproteolytic amino-terminal cleavage of this peptide at least 30 times faster than the carboxyl-terminal active site. Both active sites cleaved a carboxyl-terminal tripeptide from luteinizing hormone-releasing hormone. Thus, both active sites of ACE possess dipeptidyl carboxypeptidase and endopeptidase activities. However, only the carboxyl-terminal active site can undergo a chloride-induced alteration that greatly enhances the hydrolysis of AI or substance P, and the amino-terminal active site possesses an unusual amino-terminal endoproteolytic specificity for a natural peptide. This suggests physiologically important differences between the subsites of the two active centers, and different substrate specificity, despite the high degree of sequence homology.
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PMID:Differences in the properties and enzymatic specificities of the two active sites of angiotensin I-converting enzyme (kininase II). Studies with bradykinin and other natural peptides. 768 54