Enzymatic Activity Analysis and Catalytic Essential Residues Identification of Brucella abortus Malate Dehydrogenase
Figure 4
The influence factors of enzymatic activity. (a) The conversion-rate (V) of OAA (S) to L-malate was measured at 340 nm using reaction of 1 μg of His-MDH with nd pH and d racterizationvarious concentrations of OAA (0.1875–3 mM) at pH 6.0, 40°C. Measurements were performed at 1 min intervals for 5 min. Data from 3 independent assays were plotted by the method of Michaelis-Menten and fitted to the equation . and for His-MDH were determined to be 6.45×10−3 M and 0.87 mM L−1 min−1, respectively, by means of a Lineweaver-Burk plot (double-reciprocal plot). Data shown here were the mean values ± standard deviations. (b) The maximal MDH activity occurred at pH 6.0. The experiments were performed in triplicate, and the bars represent standard deviations.
