Interaction between the biotin carboxyl carrier domain and the biotin carboxylase domain in pyruvate carboxylase from Rhizobium etli.

ABSTRACT: Pyruvate carboxylase (PC) catalyzes the ATP-dependent carboxylation of pyruvate to oxaloacetate, an important anaplerotic reaction in mammalian tissues. To effect catalysis, the tethered biotin of PC must gain access to active sites in both the biotin carboxylase domain and the carboxyl transferase domain. Previous studies have demonstrated that a mutation of threonine 882 to alanine in PC from Rhizobium etli renders the carboxyl transferase domain inactive and favors the positioning of biotin in the biotin carboxylase domain. We report the 2.4 Å resolution X-ray crystal structure of the Rhizobium etli PC T882A mutant which reveals the first high-resolution description of the domain interaction between the biotin carboxyl carrier protein domain and the biotin carboxylase domain. The overal

SUBMITTER: Lietzan AD 

PROVIDER: S-EPMC3214759 | biostudies-literature | 2011 Nov

REPOSITORIES: biostudies-literature