title: Enzymatic biosynthesis of cephalexin.
abstract: The reaction kinetics of the enzymatic synthesis of cephalexin from 7-aminodeacetoxy cephalosporanic acid and phenylglycine methylester was studied using the synthesizing enzyme obtained from Xanthomonas citri. The activation energy, Km values for 7-aminodeacetoxy cephalosporanic acid and phenylglycine methylester, and Ki value for phenylglycine methylester were determined as 8.63 kcal/mol, 3.7mM, 14.5mM, and 70mM, respectively. The enzyme was found to be constitutive and susceptible to deactivation.
mesh_terms: D000581:Amidohydrolases / Q000378:metabolism*; D001565:Benzoates / Q000494:pharmacology; D002506:Cephalexin / Q000096:biosynthesis*; D004790:Enzyme Induction; D007700:Kinetics; D010100:Oxygen / Q000494:pharmacology; D010399:Penicillin Amidase / Q000096:biosynthesis / Q000378:metabolism*; D010648:Phenylacetates / Q000494:pharmacology; D014974:Xanthomonas / Q000201:enzymology
chemical_list: D001565:Benzoates; D010648:Phenylacetates; D000581:Amidohydrolases; D010399:Penicillin Amidase; D002506:Cephalexin; D010100:Oxygen