牛蛙（Rana catesbeiana）蝌蚪尾巴中组织蛋白酶D样蛋白酶的纯化与特性分析

Purification and characterization of cathepsin D-like proteinase from the tadpole tail of bullfrog, Rana catesbeiana.

Nanbu M, Kobayashi K, Horiuchi S

Life Science Institute, Sophia University, Tokyo, Japan.

Comp Biochem Physiol B. 1988;89(3):569-75. doi: 10.1016/0305-0491(88)90176-9.

Abstract

An acid aspartic proteinase in the regressing tadpole tail was purified about 800-fold with a 36% recovery. 2. The mol. wt of the enzyme was found to be 42,000 on gel filtration and 38,000 on sodium dodecyl sulfate polyacrylamide gel electrophoresis, respectively. 3. The purified enzyme had a maximum activity at pH 3.5 and an apparent Km of 0.084% with acid-denatured hemoglobin as substrate. 4. The enzyme activity was strongly inhibited by pepstatin. In addition, diazoacetylnorleucine methyl ester inactivated the enzyme in the presence of cupric ions. 5. The enzyme was identified as a cathepsin D (EC. 3.4.23.5)-like proteinase.

摘要

在正在退化的蝌蚪尾巴中，一种酸性天冬氨酸蛋白酶被纯化了约800倍，回收率为36%。2. 经凝胶过滤法测得该酶的分子量为42,000，经十二烷基硫酸钠聚丙烯酰胺凝胶电泳法测得为38,000。3. 纯化后的酶在pH 3.5时具有最大活性，以酸变性血红蛋白为底物时的表观Km为0.084%。4. 该酶的活性受到胃蛋白酶抑制剂的强烈抑制。此外，重氮乙酰正亮氨酸甲酯在铜离子存在的情况下会使该酶失活。5. 该酶被鉴定为一种组织蛋白酶D（EC. 3.4.23.5）样蛋白酶。