鉴定一种在MEL细胞分化过程中活性降低的类弹性蛋白酶活性为脯氨酰内肽酶。

Identification of an elastase-like activity, that decreased during the differentiation of MEL cells, as a prolyl endopeptidase.

Tsukahara T, Ishiura S, Sugita H

National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan.

Int J Biochem. 1991;23(1):79-83. doi: 10.1016/0020-711x(91)90012-c.

Abstract

A Suc-APA-MCA hydrolytic activity was significantly decreased in murine erythroleukemia cells during DMSO-induced differentiation, but not in DMSO-resistant cells. 2. The Suc-APA-MCA hydrolytic enzyme was purified by ion exchange, adsorption, gel filtration and affinity chromotographies. The results of the chromatographies showed that only one enzyme hydrolyzed Suc-APA-MCA in MEL cells. 3. This enzyme is more sensitive to hydrolysis by Suc-GPLGP-MCA than Suc-APA-MCA at slightly acidic pH, and its activity is stimulated by 2-mercaptoethanol. 4. A cysteine proteinase inhibitor did not affect the activity, but a specific inhibitor of prolyl endopeptidase, Z-thioprothiazolidine, completely inhibited it. These results suggest that the Suc-APA-MCA hydrolytic enzyme is identical to a prolyl endopeptidase.

摘要

在二甲基亚砜（DMSO）诱导的分化过程中，鼠红细胞白血病细胞中的琥珀酰-对氨基苯甲酰-L-丙氨酰-对甲氧基肉桂酰-L-精氨酸甲酯（Suc-APA-MCA）水解活性显著降低，但在对DMSO耐药的细胞中则没有。2. 通过离子交换、吸附、凝胶过滤和亲和层析法纯化了Suc-APA-MCA水解酶。层析结果表明，在MEL细胞中只有一种酶能水解Suc-APA-MCA。3. 在略酸性pH条件下，该酶对Suc-GPLGP-MCA水解的敏感性高于对Suc-APA-MCA的敏感性，其活性受2-巯基乙醇刺激。4. 半胱氨酸蛋白酶抑制剂不影响该活性，但脯氨酰内肽酶的特异性抑制剂Z-硫代噻唑烷能完全抑制它。这些结果表明，Suc-APA-MCA水解酶与脯氨酰内肽酶相同。