Kinetic and thermal stability studies of rulactine,a proteolytic enzyme fromMicrococcus caseolyticus

Summary Kinetics and thermostability of Rulactine, a protease fromMicrococcus caseolyticus were investigated. Study of the enzyme activity as a function of the temperature showed an optimum peak of 45°C. The effeci of the substrate concentration on the initial velocity at various temperatures was examined, and V_max and K_M were determined using a Lineweaver-Burk reciprocal plot. The activation energy evaluation gave a value of 9500 cal/mole. Studies of additives such as polyhydric alcohols (glycerol, erythritol, xylitol and sorbitol) and disaccharides (sucrose and lactose) to Rulactine at 58°C proved that they have a stabilizing effect on Rulactine.