anticapsin and glucosamine-6-phosphate

Glucosamine-6-phosphate synthetase from Escherichia coli K-12 is progressively inactivated L-beta-(2,3-epoxycyclohexyl-4-on)alanine (anticapsin). With increasing concentrations of anticapsin the reaction exhibits rate saturation: the minimum inactivation half-time is 1.15 minutes, with a Kin alpha ct of 2.5 microM. Glutamine and competitive inhibitors protect against inactivation. Fructose-6-phosphate promotes the inactivation rate. It is concluded that anticapsin is an active-site directed glutamine analog in the reaction catalyzed by glucosamine-6-phosphate synthetase.

Topics: Alanine; Binding Sites; Carbohydrate Epimerases; Escherichia coli; Glucosamine; Glucose-6-Phosphate; Glucosephosphates; Glutamine; Glutamine-Fructose-6-Phosphate Transaminase (Isomerizing); Kinetics