Bjornstad P
J Lipid Res. 1966 Sep;7(5):612-20.
The hydrolysis of endogenous phosphatidyl ethanolamine and lecithin in rat liver mitochondria has been studied by using mitochondria from rats injected with ethanolamine-1,2-(14)C or choline-1,2-(14)C. A phospholipase A-like enzyme has been demonstrated, which catalyzes the hydrolysis of one fatty acid ester linkage in phosphatidyl ethanolamine and lecithin. Phosphatidyl ethanolamine is hydrolyzed in preference to lecithin and the main reaction products are free fatty acids and lysophosphatidyl ethanolamine. The further breakdown of lysophospholipids appears to be limited in mitochondria, which indicates that lysophospholipase activity is mainly located extramitochondrially. The enzymic system is greatly stimulated by calcium ions, and also slightly by magnesium ions, while EDTA inhibits it almost completely. These findings are discussed in relation to previous observations on the effect of calcium and of EDTA on the functions of mitochondria. The possible function of the mitochondrial phospholipase for the formation of phospholipids with special fatty acids at the alpha- and -position is discussed.
利用注射了1,2-(14)C-乙醇胺或1,2-(14)C-胆碱的大鼠的线粒体，对大鼠肝线粒体中内源性磷脂酰乙醇胺和卵磷脂的水解进行了研究。已证实存在一种类似磷脂酶A的酶，它催化磷脂酰乙醇胺和卵磷脂中一个脂肪酸酯键的水解。磷脂酰乙醇胺比卵磷脂更易被水解，主要反应产物是游离脂肪酸和溶血磷脂酰乙醇胺。溶血磷脂的进一步分解在线粒体中似乎受到限制，这表明溶血磷脂酶活性主要位于线粒体外。该酶系统受到钙离子的强烈刺激，也受到镁离子的轻微刺激，而乙二胺四乙酸（EDTA）几乎完全抑制它。结合先前关于钙和EDTA对线粒体功能影响的观察结果对这些发现进行了讨论。还讨论了线粒体磷脂酶在α位和β位形成具有特殊脂肪酸的磷脂的可能功能。
