梨形四膜虫细胞中的血小板活化因子乙酰水解酶活性。

A PAF-acetylhydrolase activity in Tetrahymena pyriformis cells.

作者信息

Tselepis A D, Lekka M E, Tsoukatos D

机构信息

Department of Chemistry, University of Ioannina, Greece.

出版信息

FEBS Lett. 1991 Aug 19;288(1-2):147-50. doi: 10.1016/0014-5793(91)81022-z.

DOI:10.1016/0014-5793(91)81022-z

PMID:1908796

Abstract

Our study provides evidence for the existence of an acylhydrolase activity in Tetrahymena pyriformis cells, capable of hydrolyzing the sn-2 ester bond of the PAF molecule. This activity is mainly distributed in the microsomal fraction (76.5% of total) and has properties similar to the mammalian PAF-acetylhydrolase since it is Ca(2+)-independent, acid-labile, is inhibited by DFP and PMSF but it is not affected by egg yolk phosphatidylcholine. This microsomal acylhydrolase has apparent Km and Vmax values of 1.56 microM and 373 pmols.mg.min respectively. This is the first report of the existence of a PAF-acetylhydrolase activity in a non-mammalian cell.

摘要

我们的研究为梨形四膜虫细胞中存在酰基水解酶活性提供了证据，该酶能够水解PAF分子的sn-2酯键。这种活性主要分布在微粒体部分（占总量的76.5%），并且具有与哺乳动物PAF-乙酰水解酶相似的特性，因为它不依赖Ca(2+)，对酸不稳定，受DFP和PMSF抑制，但不受蛋黄磷脂酰胆碱影响。这种微粒体酰基水解酶的表观Km和Vmax值分别为1.56 microM和373 pmols.mg.min。这是关于非哺乳动物细胞中存在PAF-乙酰水解酶活性的首次报道。