Please use this identifier to cite or link to this item:
Title: Investigation the roles of residues controlling the direct and indirect interaction with acetyl CoA in allosteric regulation of Rhizobium etli pyruvate carboxylase
Authors: Sarawut Jitrapakdee
Keywords: pyruvate carboxylase;Rhizobium etli;acetyl CoA;allosteric regulation
Issue Date: 2015
Publisher: 2015 Published by Burapha University
Citation: Proceedings of the Burapha University International Conference 2015; ST-P-043;988-995
Abstract: We have executed the site-directed mutagenesis to study roles of 4 residues in the allosteric binding site of pyruvate carboxylase from Rhizobium etli. Arg469 mutants slightly affect the acetyl CoA-induced enzyme activity than that of Arg427 and Arg472, but they increase in enzyme activation in the absence of acetyl CoA. The three dimensional structure of pyruvate carboxylase from R. etli revealed a network interaction between Arg469, Asp471, Thr474, and Arg1059.Asp471 has the most impact on the enzyme because this mutation completely eliminates the acetyl CoA-induced enzyme activation. Glu1027 and Asp1018 mutants have small effects on acetyl CoA binding and pyruvate carboxylation activity in the presence of acetyl CoA. However, Glu1027 and Asp1018 mutants increase in the acetyl CoA-independent pyruvate carboxylation activity. It may happen from destruction of network interactions among residues in allosteric binding site which normally restrain the enzyme structure and dynamic into the inactive form in the absence of acetyl CoA. owever,more dynamic of residues does not allow the appropriate position similar in the normal active form of the enzyme in the presence of acetyl CoA because most mutation reduce the degree of activation of the enzyme by acetyl CoA (kcat/k0cat).
Appears in Collections:Biochemistry: International Proceedings

Files in This Item:
There are no files associated with this item.

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.