| 摘要 |
<p>A psychrophilic protease is here disclosed which has the following physicochemical properties: (a) specific activity and substrate specificity: the protease acts on casein, gelatin, hemoglobin and albumin to specifically decompose them in the order of casein, gelatin, hemoglobin and albumin; (b) optimal pH: 8.0; (c) pH stability: the protease is stable at a pH in the range of 6.5 to 10.0 at 30 °C for 1 hour; (d) optimal temperature: about 40 °C; (e) temperature stability: at pH 7 for 1 hour, the protease is scarcely inactivated at a temperature up to 30 °C, but it is inactivated at 40 °C as much as about 40 % and completely inactivated at 50 °C in about 10 minutes; (f) enzyme activity: the protease has about 50 % or more of its maximum activity at 20 °C; (g) the active center of the enzyme is serine; and (h) the molecular weight of the protease is about 70 kDa as measured by SDS-PAGE.</p> |
