The Michaelis constant (Km) is a measure of the affinity of the enzyme towards the substrate, with smaller values representing greater affinity. Km and the maximum rate (Vmax) of leukocyte GCase were obtained through the Lineweaver-Burk plot (Figure 4) with artificial substrate p-NPG in concentrations from 0.71 mM to2.50 mM. Km and Vmax values for leukocyte GCase using p-NPG as substrate was found to be 12.6 mM and 333 U/mg respectively.
Fig. 4. Determination of Michaelis constant of GCase for different p-NPG substrate concentrations (0.71 mM-2.50 mM) in sodium acetate buffer (50mM, pH 5.0). All the samples were assayed in the presence of 6 mg/ml sodium taurocholate and 70 μl of …show more content…
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