Phospholipid composition of highly purified mitochondrial outer membranes of rat liver and Neurospora crassa. Is cardiolipin present in the mitochondrial outer membrane?
Phospholipid composition of highly purified mitochondrial outer membranes of rat liver and Neurospora crassa. Is cardiolipin present in the mitochondrial outer membrane?
复制标题
DOI：
10.1016/s0005-2736(96)00240-4
复制
发表时间：
1997-04-03
影响因子：
3.4
通讯作者：
deKruijff, B
中科院分区：
文献类型：
--
作者：
deKroon, AIPM;Dolis, D;deKruijff, B
分离的线粒体外膜囊泡（OMV）是研究线粒体外膜各种功能的合适系统。对于线粒体脂质输入的研究以及对于脂质在外膜中发生的过程中的作用的研究，外膜的磷脂组成的知识是必不可少的。最近，描述了从粗糙脉孢菌的线粒体中分离高度纯化的OMV的温和亚分级分离方法（Mayer，A.，利尔河和Neupert，W.等（1993）J. Cell Biol.121，1233-1243）。该方法包括溶胀和机械破碎线粒体，然后进行两步蔗糖密度梯度离心，适用于从大鼠肝线粒体中分离OMV。使用适当的酶标记物，结果表明，所得OMV的产率为25%，其纯度上级于以前的OMV制剂。对OMV的磷脂组成的分析表明，磷脂酰胆碱、磷脂酰乙醇胺和磷脂酰肌醇是主要的磷脂成分，并且心磷脂仅以痕量存在。磷脂组成与来自粗糙脉孢菌线粒体的高度纯化的OMV的磷脂组成非常相似，尽管后者仍然含有少量的心磷脂。
Isolated mitochondrial outer membrane vesicles (OMV) are a suitable system for studying various functions of the mitochondrial outer membrane. For studies on mitochondrial lipid import as well as for studies on the role of lipids in processes occurring in the outer membrane, knowledge of the phospholipid composition of the outer membrane is indispensable. Recently, a mild subfractionation procedure was described for the isolation of highly purified OMV from mitochondria of Neurospora crassa (Mayer, A., Lill, R. and Neupert, W. (1993) J. Cell Biol. 121, 1233-1243). This procedure, which consists of swelling and mechanical disruption of mitochondria followed by two steps of sucrose density gradient centrifugation, was adapted for the isolation of OMV from rat liver mitochondria. Using the appropriate enzyme markers it is shown that the resulting OMV are obtained in a yield of 25%, and that their purity is superior to that of previous OMV preparations. Analysis of the phospholipid composition of the OMV showed that phosphatidylcholine, phosphatidylethanolamine and phosphatidylinositol are the major phospholipid constituents, and that cardiolipin is only present in trace amounts. The phospholipid composition is very similar to that of the highly purified OMV from mitochondria of Neurospora crassa, although the latter still contain a small amount of cardiolipin.