SUBSTRATE AND INHIBITOR SPECIFICITY OF GLUTAMINE CYCLOTRANSFERASE (QC)

Citation
My. Gololobov et al., SUBSTRATE AND INHIBITOR SPECIFICITY OF GLUTAMINE CYCLOTRANSFERASE (QC), Biological chemistry Hoppe-Seyler, 377(6), 1996, pp. 395-398
Citations number
14
Categorie Soggetti
Biology
ISSN journal
01773593
Volume
377
Issue
6
Year of publication
1996
Pages
395 - 398
Database
ISI
SICI code
0177-3593(1996)377:6<395:SAISOG>2.0.ZU;2-N
Abstract
This paper reports a systematic study of the substrate and inhibitor s pecificity of papaya latex glutamine cyclotransferase (QC). The result s showed that the second amino acid residue in N-terminal glutaminyl p eptides significantly accelerated papaya latex QC-catalyzed reactions while the third residue provided no further rate enhancement. Substrat e binding was shown to be the main specificity-determining step. Fifte en proline derivatives and dipeptides containing an N-terminal proline were tested and found to inhibit papaya latex QC. This supports our p revious molecular modeling study of the QC catalytic pathway which sug gested a structure of the reaction intermediates similar to that of L- proline.