灰鹤(Grus grus)消化系统各器官蛋白水解酶的种类和活性研究

STUDY ON KINDS AND ACTIVITIES OF PROTEOLYTIC ENZYMES IN THE DIGESTIVE SYSTEM OF GRUS GRUS

目的研究灰鹤(Grus grus)消化系统各器官蛋白水解酶的种类和性质,为探讨野生鸟类的分类地位、系统演化提供基础资料。方法采用蛋白水解酶复性电泳(G-PAGE)技术。结果1.灰鹤消化系统蛋白水解酶种类多,在各种pH条件下,共计有26种;2.灰鹤消化系统蛋白水解酶的活性受pH值的影响和制约,在中性条件下酶活性最强,酸性条件下最弱,总的酶活性表现为中性>碱性>酸性;3.同一器官在不同的pH条件下,蛋白水解酶的种类和活性有较大的变化,不同器官蛋白水解酶的最适pH条件各不相同;4.在各种pH条件下,19kD酶带普遍存在于除腺胃以外的各器官中,在中性条件下,各消化器官都分布有66和22kD两条酶带。结论灰鹤消化系统蛋白水解酶的最适pH为7.0;66、22、19kD酶带的分布、活性及pH依赖性特点是灰鹤消化系统蛋白水解酶的主要特征。

Objective The kinds and activities of proteolytie enzymes of organs in the digestive system of Grus grus were studied to provide basic information for the taxonomy and evolvement study of wild birds. Methods The experiment was carried out at 4℃ by using gelatine polyacrylamide gel electrophoresis （G-PAGE） ameliorat. Results 1. Altogether 26 kinds of proteolytic enzymes were found in the digestive system of Grus grus in all pH value conditions. 2. The kinds and activities of proteolytic enzymes in the digestive system of Grus grus were affected by pH. The activities of proteolytic enzymes were weakest in the acid environment and strongest in the neutral environment, which shows that the activities of the neutral proteolytic enzymes were stronger than those of the alkaline proteolytic enzymes, and those of the acid proteolytic enzymes were weakest. 3. The kinds and activities of proteolytic enzymes of the same organ varied tremendously in different pH value conditions. The proteolytic enzymes of different organs had different optimal pH values. 4. Proteolytic enzymes with 19 kD molecular weight existed in every organ of the digestive system except glandular stomach in all pH conditions. Proteolytic enzyme with 66 and 22 kD molecular weight was found in every organ of the digestive system in the neutral environment. Conclusion The optimal pH value of proteolytic enzymes in the digestive system of Grus grus is 7.0. The distribution, activity and pH-dependency of proteolytic enzymes of 66 kD, 22 kD, 19 kD molecular weight are the important characteristic of proteolytic enzymes in the digestive system of Grus grus.