Athauda S B, Takahashi T, Kageyama T, Takahashi K
Department of Biophysics and Biochemistry, Faculty of Science, University of Tokyo, Japan.
Biochem Biophys Res Commun. 1991 Feb 28;175(1):152-8. doi: 10.1016/s0006-291x(05)81213-6.
The processing of human gastric procathepsin E to its mature form, cathepsin E, was studied at pH 3.5. The results revealed the autocatalytic and apparently one-step conversion of procathepsin E to cathepsin E within 10 min of incubation at 14 degrees C under the conditions used. Analyses of the amino acid sequences of both procathepsin E and cathepsin E showed that cleavage occurred at the Met36-Ile37 bond to produce the mature form, cathepsin E. The NH2-terminal amino acid sequence of procathepsin E thus determined was identical with that predicted from the cDNA sequence by Azuma et al. except that the NH2-terminal glutamine residue in the latter was converted into a pyroglutamic acid residue in the former and that the glycine residue at position 2 in the latter sequence was deleted in the former. On the other hand, the NH2-terminal amino acid sequence of cathepsin E was identical with that reported previously by us.
在pH 3.5条件下研究了人胃组织中组织蛋白酶E原向其成熟形式——组织蛋白酶E的加工过程。结果显示，在所使用的条件下，于14℃孵育10分钟内，组织蛋白酶E原可自动催化并明显一步转化为组织蛋白酶E。对组织蛋白酶E原和组织蛋白酶E的氨基酸序列分析表明，切割发生在Met36-Ile37键处，从而产生成熟形式的组织蛋白酶E。由此确定的组织蛋白酶E原的NH2末端氨基酸序列与Azuma等人从cDNA序列预测的序列相同，只是后者的NH2末端谷氨酰胺残基在前者中转化为焦谷氨酸残基，并且后者序列中第2位的甘氨酸残基在前者中缺失。另一方面，组织蛋白酶E的NH2末端氨基酸序列与我们之前报道的一致。
