文章基本信息

标题：Separate myocardial ethanolamine phosphotransferase activities responsible for plasmenylethanolamine and phosphatidylethanolamine synthesis
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作者：David A. Ford
期刊名称：JLR Papers In Press
印刷版ISSN：0022-2275
电子版ISSN：1539-7262
出版年度：2003
卷号：44
期号：3
页码：554-559
DOI：10.1194/jlr.M200426-JLR200
语种：English
出版社：American Society for Biochemistry and Molecular Biology
摘要：Ethanolamine phosphotransferase (EPT) is a key enzyme responsible for the synthesis of ethanolamine glycerophospholipids. Plasmenylethanolamine is a predominant molecular subclass of ethanolamine glycerophospholipids in the heart. The present study was designed to identify the selective use of 1- O -alk-1′-enyl-2-acyl- sn -glycerol as a substrate for EPT as a mechanism responsible for the predominance of plasmenylethanolamine in the rabbit heart. EPT activity in rabbit myocardial membranes using 1,2-diacyl- sn -glycerol as substrate is activated by Mn²⁺, inhibited by dithiobisnitrobenzoic acid (DTNB) and is unaffected by Ca²⁺. In contrast, ethanolamine phosphotransferase activity using 1- O -alk-1′-enyl-2-acyl- sn -glycerol as substrate is inhibited by Mn²⁺ and Ca²⁺, but is activated by DTNB. Additionally, ethanolamine phosphotransferase activity using 1- O -alk-1′-enyl-2-acyl- sn -glycerol substrate was more sensitive to thermal denaturation compared with that of 1,2-diacyl- sn -glycerol. Taken together, these results suggest that separate ethanolamine phosphotransferase activities are present in heart membranes that are responsible for the synthesis of phosphatidylethanolamine and plasmenylethanolamine.