一种来自狗胃的胃蛋白酶原。

A pepsinogen from dog stomach.

Twining S S, Huibregtse K, Glick D M

Comp Biochem Physiol B. 1983;75(1):103-7. doi: 10.1016/0305-0491(83)90045-7.

Abstract

A pepsinogen has been purified from dog stomach in 20% yield. 2. At pH values below 4 it spontaneously converts to a pepsin, the first order rate constant at pH 2, 22 degrees C, being 11 min-1. 3. The pepsinogen is stable to denaturation at pH values up to 9, in contrast to the pepsin which is irreversibly denatured above pH 7. 4. Its proteolytic activity against denatured hemoglobin is equal to that of pig pepsin, but in the milk-clotting assay at pH 5.5 its has only 14% the activity.

摘要

已从狗胃中纯化出一种胃蛋白酶原，产率为20%。2. 在pH值低于4时，它会自发转化为胃蛋白酶，在pH 2、22℃时的一级速率常数为11分钟⁻¹。3. 与在pH值高于7时会不可逆变性的胃蛋白酶不同，该胃蛋白酶原在pH值高达9时对变性稳定。4. 它对变性血红蛋白的蛋白水解活性与猪胃蛋白酶相当，但在pH 5.5的凝乳试验中，其活性仅为猪胃蛋白酶的14%。