Spin-label studies on the specificity of interaction of cardiolipin with beef heart cytochrome oxidase.
Spin-label studies on the specificity of interaction of cardiolipin with beef heart cytochrome oxidase.
复制标题
心磷脂与牛心细胞色素氧化酶相互作用特异性的自旋标记研究。
DOI：
10.1021/bi00399a018
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发表时间：
1987
期刊：
影响因子：
2.9
通讯作者：
D. Marsh
中科院分区：
文献类型：
--
作者：
G. Powell;P. Knowles;D. Marsh
用电子自旋共振技术研究了不同心磷脂类似物与牛心细胞色素氧化酶在与二肉豆蔻酰磷脂酰胆碱重组复合物中相互作用的选择性。在心磷脂和其单溶血衍生物之间没有观察到选择性的差异，并且类似地，在磷脂酰胆碱和溶血磷脂酰胆碱之间没有观察到选择性。通过磷酸基团的甲基化去除心磷脂电荷降低但不消除相对于磷脂酰胆碱的选择性。头基和链组成的脂质选择性的依赖性是在顺序心磷脂约等于monolysocardiolipin大于酰基心磷脂大于二甲基心磷脂大于磷脂酰胆碱约等于溶血磷脂酰胆碱，其中酰基心磷脂具有自旋标记链连接在中心-OH的头基。带负电荷的心磷脂衍生物与细胞色素氧化酶的关联程度随着盐浓度的增加而降低，达到与二甲基心磷脂相当的水平。在高离子强度下，相对于磷脂酰胆碱仍有显著的选择性。Li+离子比Na+离子更有效地屏蔽相互作用，二价离子比一价离子更有效。对心磷脂的选择性仅略微降低滴定的蛋白质，以高pH值。烷基化的蛋白质与N-乙基马来酰亚胺的滴定行为的影响不大。通过与柠康酸酐反应的蛋白质的共价修饰降低了与心磷脂相互作用的选择性。它的结论是，心磷脂具有一个额外的特异性与细胞色素氧化酶的其他纯粹的静电起源的相互作用。
The selectivity of interaction of various cardiolipin analogues with beef heart cytochrome oxidase in reconstituted complexes with dimyristoylphosphatidylcholine has been studied by electron spin resonance spectroscopy, using lipids spin-labeled in the acyl chains. No difference in selectivity is observed between cardiolipin and its monolyso derivative, and similarly no selectivity is observed between phosphatidylcholine and lysophosphatidylcholine. Removal of the cardiolipin charge by methylation of the phosphate groups reduces but does not eliminate selectivity relative to phosphatidylcholine. The dependence of the lipid selectivity on head group and chain composition is in the order cardiolipin approximately equal to monolysocardiolipin greater than acylcardiolipin greater than dimethylcardiolipin greater than phosphatidylcholine approximately equal to lysophosphatidylcholine, where acylcardiolipin has the spin-label chain attached at the center -OH of the head group. The degree of association of the negatively charged cardiolipin derivatives with cytochrome oxidase decreases with increasing salt concentration, to a level comparable to that for dimethylcardiolipin. At high ionic strength there is still a marked selectivity relative to phosphatidylcholine. Li+ ions are more effective in screening the interaction than are Na+ ions, and divalent ions are more effective than monovalent ions. The selectivity for cardiolipin is only slightly reduced on titrating the protein to high pH. Alkylation of the protein with N-ethylmaleimide has little effect on the titration behavior. Covalent modification of the protein by reaction with citraconic anhydride decreases the selectivity of interaction with cardiolipin. It is concluded that cardiolipin possesses an additional specificity of interaction with cytochrome oxidase other than that of purely electrostatic origin.
脂质成分对肌浆网Ca2-ATP酶钙/腺苷5-三磷酸偶联比的影响。
影响因子：
2.9
作者：
Navarro,J;Toivio-Kinnucan,M;Racker,E
通讯作者：
Racker,E