A Symmetrical Tetramer for S. aureus Pyruvate Carboxylase in Complex with Coenzyme A

Journal Article · Thu Jan 01 04:00:00 EST 2009 · Structure

DOI:https://doi.org/10.1016/j.str.2009.04.008· OSTI ID:979990

Yu, L; Xiang, S; Lasso, G; Gil, D; Valle, M; Tong, L

Pyruvate 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.

• Research Organization: Brookhaven National Laboratory (BNL) National Synchrotron Light Source
• Sponsoring Organization: Doe - Office Of Science
• DOE Contract Number: AC02-98CH10886
• OSTI ID: 979990
• Report Number(s): BNL--92908-2010-JA
• Journal Information: Structure, Journal Name: Structure Journal Issue: 6 Vol. 17
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
59 BASIC BIOLOGICAL SCIENCES
99 GENERAL AND MISCELLANEOUS
BIOTIN
CARBOXYLASE
CHANNELING
COENZYMES
CRYSTAL STRUCTURE
DIMERS
ENZYMES
FUNCTIONS
INFORMATION
MICROSCOPY
MOLECULES
MUTAGENESIS
MUTATIONS
RHIZOBIUM
STAPHYLOCOCCUS
national synchrotron light source