Formation of molecular species of mitochondrial cardiolipin. 1. A novel transacylation mechanism to shuttle fatty acids between sn-1 and sn-2 positions of multiple phospholipid species
Formation of molecular species of mitochondrial cardiolipin. 1. A novel transacylation mechanism to shuttle fatty acids between sn-1 and sn-2 positions of multiple phospholipid species
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DOI：
10.1016/j.bbalip.2009.01.004
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发表时间：
2009-04-01
影响因子：
4.8
通讯作者：
Schlame, Michael
中科院分区：
文献类型：
--
作者：
Malhotra, Ashim;Xu, Yang;Schlame, Michael
线粒体心磷脂经历其酰基的广泛重塑以产生均匀取代的物质，例如四氢萘油酰基-心磷脂，但这种重塑的机制尚未阐明，除了它需要tafazzin的事实。在这里，我们表明，纯化的重组果蝇tafazzin交换心磷脂和磷脂酰胆碱之间的正向和反向transacylations相结合的酰基。在没有磷脂酶A的情况下，酰基交换是可能的（2），因为它只需要微量的溶血磷脂。我们表明，纯化的tafazzin反应与各种磷脂类和各种酰基在sn-1和sn-2位置。在Sf 9昆虫细胞中的表达研究表明，他法津对心磷脂种类的影响取决于细胞环境，而不是酶底物特异性。我们的数据表明，tafazzin催化磷脂之间的一般酰基交换，这就提出了一个问题，是否在心磷脂的模式形成的结果是多个磷脂物种之间的酰基平衡分布。(c)2009爱思唯尔有限公司版权所有。
Mitochondrial cardiolipin undergoes extensive remodeling of its acyl groups to generate uniformly substituted species, such as tetralinoleoyl-cardiolipin, but the mechanism of this remodeling has not been elucidated, except for the fact that it requires tafazzin. Here we show that purified recombinant Drosophila tafazzin exchanges acyl groups between cardiolipin and phosphatidylcholine by a combination of forward and reverse transacylations. The acyl exchange is possible in the absence of phospholipase A(2) because it requires only trace amounts of lysophospholipids. We show that purified tafazzin reacts with various phospholipid classes and with various acyl groups both in sn-1 and sn-2 position. Expression studies in Sf9 insect cells suggest that the effect of tafazzin on cardiolipin species is dependent on the cellular environment and not on enzymatic substrate specificity. Our data demonstrate that tafazzin catalyzes general acyl exchange between phospholipids, which raises the question whether pattern formation in cardiolipin is the result of the equilibrium distribution of acyl groups between multiple phospholipid species. (c) 2009 Elsevier B.V. All rights reserved.