Linked Life Data

3293664

Source:http://linkedlifedata.com/resource/pubmed/id/3293664

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1988-9-2
pubmed:abstractText
Thymopentin (Arg-Lys-Asp-Val-Tyr) was shown to be degraded in vitro by human lymphocytes into two main fragments; the tetrapeptide Lys-Asp-Val-Tyr and the tripeptide Asp-Val-Tyr. Degradation products were identified by HPLC and amino-acid analysis. Analysis of the time-course of degradation revealed a 'stepwise' degradative event beginning at the N-terminal. The degradation of thymopentin after the first 10 min, as well as the formation of the tetrapeptide (5-30 min) were essentially curvilinear. Degradation of the tripeptide, was linear. Upon screening a panel of compounds that inhibit enzymatic activity, bestatin, amastatin and 1,10-phenanthroline were shown to be the most effective. Bestatin and amastatin caused an 85-90% inhibition of thymopentin degrading activity with IC50 values of 7.1 x 10(-6) M and 4.5 x 10(-9) M, respectively. 1,10-Phenanthroline completely inhibited the degradative process with an IC50 of 2 x 10(-4) M. When the tetrapeptide Lys-Asp-Val-Tyr was used as the starting substrate, similar IC50 values were seen for amastatin, bestatin and 1,10-phenanthroline. The importance of divalent metal ions in the degradative event was demonstrated not only by the effect of 1,10-phenanthroline, but also by the ability of Zn2+ and Co2+ to reverse the inhibition of 1,10-phenanthroline (at its IC50) to activities near control values (no inhibitor). These data strongly suggest that an aminopeptidase(s) is responsible for the degradative activity.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/1,10-phenanthroline, http://linkedlifedata.com/resource/pubmed/chemical/Aminopeptidases, http://linkedlifedata.com/resource/pubmed/chemical/Anti-Bacterial Agents, http://linkedlifedata.com/resource/pubmed/chemical/Leucine, http://linkedlifedata.com/resource/pubmed/chemical/Oligopeptides, http://linkedlifedata.com/resource/pubmed/chemical/Peptide Fragments, http://linkedlifedata.com/resource/pubmed/chemical/Peptides, http://linkedlifedata.com/resource/pubmed/chemical/Phenanthrolines, http://linkedlifedata.com/resource/pubmed/chemical/Thymopentin, http://linkedlifedata.com/resource/pubmed/chemical/Thymopoietins, http://linkedlifedata.com/resource/pubmed/chemical/Thymus Hormones, http://linkedlifedata.com/resource/pubmed/chemical/amastatin, http://linkedlifedata.com/resource/pubmed/chemical/bestatin
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:day
20
pubmed:volume
955
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
164-74
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
Degradation of thymopentin by human lymphocytes: evidence for aminopeptidase activity.
pubmed:affiliation
Department of Surgery, University of Cincinnati College of Medicine, OH 45267-0558.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't