**4.5.8 Kinetic parameters**

In order to evaluate the kinetic constants for the purified protease, the initial velocities of the enzyme reactions were determined at various concentrations of the casein substrate. The kinetic constants, *Km* and *Vmax* values of the protease were calculated from the Lineweaver-Burk plot. The *Vmax*/*Km* value, which is the physiological or catalysis efficiency value, was calculated. The higher *Vmax*/*Km* value means the stronger catalytic activity to hydrolyze the substrate. Therefore the protease produced by *B. subtilis* JM3 exhibited the strongest catalytic activity among the three salt –tolerant acid proteases.


Table 8. Kinetic parameters of the purified protease produced by *Bacillus subtilis* JM3, *Bacillus megaterium* KLP-98, and *Aspergillus oryzae* LK-101 (W.J. Kim and S.M. Kim, 2005; Fu et al., 2008; Hwang et al., 2010).
