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Catalytic site studies on tuna (Thunnus albacares) pyloric caeca aminopeptidase
Tuna pyloric caeca aminopeptidase (tAP) is a glycosylated zinc-metalloenzyme containing apparently two identical subunits. The enzyme is reversibly inhibited in a time-dependent manner by amastatin. Slow development of tAP inhibition by this inhibitor could be demonstrated. Dissociation of the compl...
Autores principales: | , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Published by Elsevier B.V.
1995
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7148818/ https://www.ncbi.nlm.nih.gov/pubmed/7669802 http://dx.doi.org/10.1016/0167-4838(95)00099-G |
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author | Hajjou, Mustapha Le Gal, Yves |
author_facet | Hajjou, Mustapha Le Gal, Yves |
author_sort | Hajjou, Mustapha |
collection | PubMed |
description | Tuna pyloric caeca aminopeptidase (tAP) is a glycosylated zinc-metalloenzyme containing apparently two identical subunits. The enzyme is reversibly inhibited in a time-dependent manner by amastatin. Slow development of tAP inhibition by this inhibitor could be demonstrated. Dissociation of the complex of tAP with amastatin is also slow. Two molar equivalents of the inhibitor are bound by the enzyme suggesting the presence of one catalytic site in each subunit. Chemical modification of tAP with 1-cyclohexyl-3-(2-morpholinoethyl)carbonyl-metho-p-toluene sulfonate and N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinone revealed the presence of essential acidic amino acid residues probably located at the active site. Compatible with the presence of arginine and tyrosine residues at the catalytic site of most metalloproteinases, tAP is reversibly inhibited by phenylglyoxal and inactivated by tetranitromethane in a time-dependent fashion. The rate of inhibition by these modifiers could be significantly decreased if the enzyme was previously treated with amastatin suggesting that the modified amino acid residues are located at the catalytic site. Diethylpyrocarbonate did not affect the activity of both native and zinc-depleted tAP suggesting that histidine is not involved in the zinc-ligand formation. |
format | Online Article Text |
id | pubmed-7148818 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 1995 |
publisher | Published by Elsevier B.V. |
record_format | MEDLINE/PubMed |
spelling | pubmed-71488182020-04-13 Catalytic site studies on tuna (Thunnus albacares) pyloric caeca aminopeptidase Hajjou, Mustapha Le Gal, Yves Biochimica et Biophysica Acta (BBA) - Protein Structure and Molecular Enzymology Article Tuna pyloric caeca aminopeptidase (tAP) is a glycosylated zinc-metalloenzyme containing apparently two identical subunits. The enzyme is reversibly inhibited in a time-dependent manner by amastatin. Slow development of tAP inhibition by this inhibitor could be demonstrated. Dissociation of the complex of tAP with amastatin is also slow. Two molar equivalents of the inhibitor are bound by the enzyme suggesting the presence of one catalytic site in each subunit. Chemical modification of tAP with 1-cyclohexyl-3-(2-morpholinoethyl)carbonyl-metho-p-toluene sulfonate and N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinone revealed the presence of essential acidic amino acid residues probably located at the active site. Compatible with the presence of arginine and tyrosine residues at the catalytic site of most metalloproteinases, tAP is reversibly inhibited by phenylglyoxal and inactivated by tetranitromethane in a time-dependent fashion. The rate of inhibition by these modifiers could be significantly decreased if the enzyme was previously treated with amastatin suggesting that the modified amino acid residues are located at the catalytic site. Diethylpyrocarbonate did not affect the activity of both native and zinc-depleted tAP suggesting that histidine is not involved in the zinc-ligand formation. Published by Elsevier B.V. 1995-09-06 2001-06-22 /pmc/articles/PMC7148818/ /pubmed/7669802 http://dx.doi.org/10.1016/0167-4838(95)00099-G Text en Copyright © 1995 Published by Elsevier B.V. Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. |
spellingShingle | Article Hajjou, Mustapha Le Gal, Yves Catalytic site studies on tuna (Thunnus albacares) pyloric caeca aminopeptidase |
title | Catalytic site studies on tuna (Thunnus albacares) pyloric caeca aminopeptidase |
title_full | Catalytic site studies on tuna (Thunnus albacares) pyloric caeca aminopeptidase |
title_fullStr | Catalytic site studies on tuna (Thunnus albacares) pyloric caeca aminopeptidase |
title_full_unstemmed | Catalytic site studies on tuna (Thunnus albacares) pyloric caeca aminopeptidase |
title_short | Catalytic site studies on tuna (Thunnus albacares) pyloric caeca aminopeptidase |
title_sort | catalytic site studies on tuna (thunnus albacares) pyloric caeca aminopeptidase |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7148818/ https://www.ncbi.nlm.nih.gov/pubmed/7669802 http://dx.doi.org/10.1016/0167-4838(95)00099-G |
work_keys_str_mv | AT hajjoumustapha catalyticsitestudiesontunathunnusalbacarespyloriccaecaaminopeptidase AT legalyves catalyticsitestudiesontunathunnusalbacarespyloriccaecaaminopeptidase |