National Center for
3TAT: Tyrosine Aminotransferase From E. Coli
Crystallization and preliminary crystallographic analysis of the Escherichia coli tyrosine aminotransferase
Acta Crystallogr. D Biol. Crystallogr. (1999) 55 p.1474-1477
Tyrosine aminotransferase catalyzes transamination for both dicarboxylic and aromatic amino-acid substrates. The substrate-free Escherichia coli tyrosine aminotransferase (eTAT) bound with the cofactor pyridoxal 5'-phosphate (PLP) was crystallized in the trigonal space group P3(2). A low-resolution crystal structure of eTAT was determined by molecular-replacement methods. The overall folding of eTAT resembles that of the aspartate aminotransferases, with the two identical subunits forming a dimer in which each monomer binds a PLP molecule via a covalent bond linked to the epsilon-NH(2) group of Lys258. Comparison of the structure of eTAT with those of the open, half-open or closed form of chicken or E. coli aspartate aminotransferases shows the eTAT structure to be in the open conformation.