Insight into the carboxyl transferase domain mechanism of pyruvate carboxylase from Rhizobium etli.

ABSTRACT: The effects of mutations in the active site of the carboxyl transferase domain of Rhizobium etli pyruvate carboxylase have been determined for the forward reaction to form oxaloacetate, the reverse reaction to form MgATP, the oxamate-induced decarboxylation of oxaloacetate, the phosphorylation of MgADP by carbamoyl phosphate, and the bicarbonate-dependent ATPase reaction. Additional studies with these mutants examined the effect of pyruvate and oxamate on the reactions of the biotin carboxylase domain. From these mutagenic studies, putative roles for catalytically relevant active site residues were assigned and a more accurate description of the mechanism of the carboxyl transferase domain is presented. The T882A mutant showed no catalytic activity for reactions involving the carboxyl tran

SUBMITTER: Zeczycki TN 

PROVIDER: S-EPMC2746095 | biostudies-literature | 2009 May

REPOSITORIES: biostudies-literature