Chorismate synthase. Pre-steady-state kinetics of phosphate release from 5-enolpyruvylshikimate 3-phosphate

Abstract
The pre-steady-state kinetics of phosphate formation from 5-enolpyruvylshikimate 3-phosphate catalysed by Escherichia coli chorismate synthase (EC 4.6.1.4) were studied by a rapid-acid-quench technique at 25.degree.C at pH 7.5. No pre-steady-state ''burst'' or ''lag'' phase was observed, showing that phosphate is released concomitant with the rate-limiting step of the enzyme. The implications of this result for the mechanism of action of chorismate synthase are discussed.