3hb9 | pdb_00003hb9
Crystal Structure of S. aureus Pyruvate Carboxylase A610T Mutant
Structural highlights
Function[Q99UY8_STAAM] Catalyzes a 2-step reaction, involving the ATP-dependent carboxylation of the covalently attached biotin in the first step and the transfer of the carboxyl group to pyruvate in the second (By similarity).[PIRNR:PIRNR001594] Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedPyruvate carboxylase (PC) is a conserved metabolic enzyme with important cellular functions. We report crystallographic and cryo-electron microscopy (EM) studies of Staphylococcus aureus PC (SaPC) in complex with acetyl-CoA, an allosteric activator, and mutagenesis, biochemical, and structural studies of the biotin binding site of its carboxyltransferase (CT) domain. The disease-causing A610T mutation abolishes catalytic activity by blocking biotin binding to the CT active site, and Thr908 might play a catalytic role in the CT reaction. The crystal structure of SaPC in complex with CoA reveals a symmetrical tetramer, with one CoA molecule bound to each monomer, and cryo-EM studies confirm the symmetrical nature of the tetramer. These observations are in sharp contrast to the highly asymmetrical tetramer of Rhizobium etli PC in complex with ethyl-CoA. Our structural information suggests that acetyl-CoA promotes a conformation for the dimer of the biotin carboxylase domain of PC that might be catalytically more competent. A symmetrical tetramer for S. aureus pyruvate carboxylase in complex with coenzyme A.,Yu LP, Xiang S, Lasso G, Gil D, Valle M, Tong L Structure. 2009 Jun 10;17(6):823-32. PMID:19523900[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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