Matern H, Barth R, Holzer H
Biochim Biophys Acta. 1979 Apr 12;567(2):503-10. doi: 10.1016/0005-2744(79)90136-0.
The purification as well as some characteristics of the carboxypeptidase Y-inhibitor from baker's yeast have been described in a previous report (Matern, H., Hoffmann, M. and Holzer, H. (1974) Proc. Natl. Acad. Sci. U.S. 71, 4874-4878). In this paper, chemical and physical properties of the purified inhibitor are presented. The molecular weight was estimated at 23 400--24 000 and appears to be a monomeric unit. Amino acid analysis and carbohydrate studies are given, showing the existence of three disulfide bonds and one sulfhydryl group per molecule and the absence of carbohydrate residues. The N-terminal amino acid is blocked by an acetyl group. The C-terminal amino acid is lysine. The isoelectric point (pI) is 6.6 and the inhibitor-enzyme complex is stable (at 25 degrees C) betwen pH 5 and 9. The apparent Ki value was calculated as 2.5.10(-9)M.
之前的一篇报告（Matern, H., Hoffmann, M. 和 Holzer, H. (1974) Proc. Natl. Acad. Sci. U.S. 71, 4874 - 4878）中已经描述了从面包酵母中提取的羧肽酶Y抑制剂的纯化方法及其一些特性。在本文中，给出了纯化抑制剂的化学和物理性质。分子量估计为23400 - 24000，似乎是一个单体单元。给出了氨基酸分析和碳水化合物研究结果，显示每个分子存在三个二硫键和一个巯基，且不存在碳水化合物残基。N端氨基酸被乙酰基封闭。C端氨基酸是赖氨酸。等电点（pI）为6.6，抑制剂 - 酶复合物在pH 5至9之间（25℃）稳定。表观Ki值计算为2.5×10⁻⁹M。
