title: Allostery and cooperativity in Escherichia coli aspartate transcarbamoylase.
abstract: The allosteric enzyme aspartate transcarbamoylase (ATCase) from Escherichia coli has been the subject of investigations for approximately 50 years. This enzyme controls the rate of pyrimidine nucleotide biosynthesis by feedback inhibition, and helps to balance the pyrimidine and purine pools by competitive allosteric activation by ATP. The catalytic and regulatory components of the dodecameric enzyme can be separated and studied independently. Many of the properties of the enzyme follow the Monod, Wyman Changeux model of allosteric control thus E. coli ATCase has become the textbook example. This review will highlight kinetic, biophysical, and structural studies which have provided a molecular level understanding of how the allosteric nature of this enzyme regulates pyrimidine nucleotide biosynthesis.
authors.affiliation: Department of Chemistry, Boston College, Merkert Chemistry Center, Chestnut Hill, MA 02467, USA. evan.kantrowitz@bc.edu
authors.forename: Evan R
authors.initials: ER
authors.lastname: Kantrowitz
mesh_terms: D000494:Allosteric Regulation; D001221:Aspartate Carbamoyltransferase / Q000737:chemistry* / Q000378:metabolism*; D020134:Catalytic Domain; D004926:Escherichia coli / Q000201:enzymology*; D007700:Kinetics; D020836:Protein Structure, Quaternary
chemical_list: D001221:Aspartate Carbamoyltransferase