Fig. 4

Kinetics of acetate inhibition of ALR and ALR^A131K. a, b ALR and ALR^A131K were assayed for 5 min at 30 °C and pH 7.0 (MES buffer) using various concentrations of l-alanine and acetate as the substrate and inhibitor, respectively. Shown are double reciprocal plots of the initial velocity of ALR (a) or ALR^A131K (b) against l-alanine concentrations at several concentrations of acetate (n = 3 for each enzyme). Open circles, without acetate; filled circles, 1.0 mM acetate; open squares, 10.0 mM acetate; filled squares, 20.0 mM acetate; open triangles, 40.0 mM acetate