Figure 1. Differential pH response of Hexokinase activity at pH 4 and 5. Hexokinase activities were measured at three concentrations of glucose (0, 20 and 40 mM), at different levels of pH, using 2 units of hexokinase (2.0 U = 10 µL x 0.2 U/µL). Not significant responses were determined at pH 4 and 5.