Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UNIPROT:P15088 (
mast cell
)
14,925
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Here we investigated the possible association between the
carboxypeptidase A
(
CPA
)-like activity of the rat mesenteric arterial bed (MAB) perfusate and the ability of this fluid of forming angiotensin (Ang) 1-9 and Ang 1-7 upon incubation with Ang I and Ang II, respectively. Initially, we observed that anion exchange chromatography of the perfusate would consistently split the characteristic Z-Val-Phe-hydrolyzing activity of
CPA
-like enzymes into five distinct peaks, whose proteolytic activities were then determined using also Ang I and Ang II as substrates. The resulting proteolytic profile for each peak indicated that rat MAB perfusate contains a complex mixture of carboxypeptidases; tentatively, five carboxypeptidases were distinguished based on their substrate preferences toward Z-Val-Phe, Ang I and Ang II. The respective reactions, namely, Z-Val-Phe cleavage, Ang I to Ang 1-9 conversion and Ang II to Ang 1-7 conversion, were inhibited by 1,10-phenanthroline and nearly fully blocked by potato carboxypeptidase inhibitor. Also, all the
CPA
-like activity peaks prepared by anion exchange chromatography were tested negative for contaminating Ang I-converting enzyme-2, cathepsin A and
prolylcarboxypeptidase
. Overall, our results indicate that rat MAB perfusate contains a multiplicity of Ang I and Ang II-processing
CPA
-like enzymes whose proteolytic specificities suggest they might perform peculiar regulatory roles in the local renin-angiotensin system.
...
PMID:Angiotensin processing is partially carried out by carboxypeptidases in the rat mesenteric arterial bed perfusate. 1883 88
Through processing peptide and protein C termini, carboxypeptidases participate in the regulation of various biological processes. Few tools are however available to study the substrate specificity profiles of these enzymes. We developed a proteome-derived peptide library approach to study the substrate preferences of carboxypeptidases. Our COFRADIC-based approach takes advantage of the distinct chromatographic behavior of intact peptides and the proteolytic products generated by the action of carboxypeptidases, to enrich the latter and facilitate its MS-based identification. Two different peptide libraries, generated either by chymotrypsin or by metalloendopeptidase Lys-N, were used to determine the substrate preferences of human metallocarboxypeptidases A1 (hCPA1), A2 (hCPA2), and A4 (hCPA4). In addition, our approach allowed us to delineate the substrate specificity profile of mouse
mast cell
carboxypeptidase (MC-CPA or mCPA3), a carboxypeptidase suggested to function in innate immune responses regulation and
mast cell
granule homeostasis, but which thus far lacked a detailed analysis of its substrate preferences. mCPA3 was here shown to preferentially remove bulky aromatic amino acids, similar to hCPA2. This was also shown by a hierarchical cluster analysis, grouping hCPA1 close to hCPA4 in terms of its P1 primed substrate specificity, whereas hCPA2 and mCPA3 cluster separately. The specificity profile of mCPA3 may further aid to elucidate the function of this
mast cell
carboxypeptidase and its biological substrate repertoire. Finally, we used this approach to evaluate the substrate preferences of
prolylcarboxypeptidase
, a serine carboxypeptidase shown to cleave C-terminal amino acids linked to proline and alanine.
...
PMID:Proteome-derived peptide libraries to study the substrate specificity profiles of carboxypeptidases. 2362 May 45