Henri-Michaelis-Menten plot for the hydrolysis ofp-NP-Neu5Ac by NanA. The normalized initial rates (V0/E0) are plotted as a function of substrate concentration, showing the perfect agreement between the initial rates measured with the conventional indirect method (empty circles) and our direct method (black circles). Reactions followed a first-order kinetics. Inset. An example of complete hydrolysis time course of 116, 232 and 464 μM p-NP-Neu5Ac (dotted, dashed and plain line, respectively) by 100 nM NanA, which allowed to compute the catalytic efficiency as described by DeMeester et al.
Hayre et al. BMC Biochemistry 2012 13:19 doi:10.1186/1471-2091-13-19