激肽释放酶直接生成血管紧张素的证实。

Confirmation of direct angiotensin formation by kallikrein.

作者信息

Maruta H, Arakawa K

出版信息

Biochem J. 1983 Jul 1;213(1):193-200. doi: 10.1042/bj2130193.

DOI:10.1042/bj2130193

PMID:6555043

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC1152108/

Abstract

This study was undertaken to confirm our previous preliminary observation that hog pancreas kallikrein (EC 3.4.21.35) directly liberated an angiotensin-like substance from human plasma protein Cohn fraction IV-4 at an acidic pH of 4.0-5.0. First, the possibility of proangiotensin or des-Asp1-angiotensin being the pressor substance was ruled out by t.l.c. Secondly, the pressor substance was purified by Sephadex G-25 and Bio-Gel P-2 gel filtration, and finally by high-performance liquid chromatography. The amino acid composition of the isolated pressor substance (residues/mol) was: Asp, 1.03; Val, 1.03; Ile, 1.00; Tyr, 0.69; Phe, 1.04; His, 0.91; Arg, 0.86; Pro, 0.86. This composition was identical with that of angiotensin. Since the reaction mixture was not contaminated with common proteolytic enzymes, such as trypsin, chymotrypsin, renin, cathepsin D and proangiotensin-converting enzyme, and other enzymes activated by kallikrein, it is clear that hog kallikrein directly produces angiotensin in vitro.

摘要

本研究旨在证实我们之前的初步观察结果，即在pH值为4.0 - 5.0的酸性条件下，猪胰激肽释放酶（EC 3.4.21.35）可直接从人血浆Cohn组分IV - 4中释放出一种血管紧张素样物质。首先，通过薄层层析排除了血管紧张素原或去天冬氨酸1 - 血管紧张素作为升压物质的可能性。其次，通过Sephadex G - 25和Bio - Gel P - 2凝胶过滤对升压物质进行纯化，最后通过高效液相色谱法进行纯化。分离出的升压物质的氨基酸组成（每摩尔残基）为：天冬氨酸，1.03；缬氨酸，1.03；异亮氨酸，1.00；酪氨酸，0.69；苯丙氨酸，1.04；组氨酸，0.91；精氨酸，0.86；脯氨酸，0.86。该组成与血管紧张素的组成相同。由于反应混合物未被常见的蛋白水解酶如胰蛋白酶、糜蛋白酶、肾素、组织蛋白酶D和血管紧张素转换酶以及其他被激肽释放酶激活的酶污染，显然猪激肽释放酶在体外可直接产生血管紧张素。