Diphosphatidylglycerol is required for optimal activity of beef heart cytochrome c oxidase.
Diphosphatidylglycerol is required for optimal activity of beef heart cytochrome c oxidase.
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二磷脂酰甘油是牛心细胞色素 C 氧化酶最佳活性所必需的。
DOI：
10.1073/pnas.78.3.1456
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发表时间：
1981
影响因子：
11.1
通讯作者：
Capaldi,RA
中科院分区：
文献类型：
--
作者：
Vik,SB;Georgevich,G;Capaldi,RA
分离的牛心细胞色素c氧化酶(亚铁细胞色素c：氧氧化还原酶，EC 1.9.3.1)每个单体含有四个或五个紧密结合的二磷脂酰甘油(2-血红素复合体)。通过将酶与高浓度的Triton X-100混合，然后通过在同一洗涤剂中平衡的甘油梯度对混合物进行离心，可以部分或全部去除这种脂质。在1-油酰化溶血磷脂酰胆碱中，每个单体保留三个或三个以上二磷脂酰甘油分子的细胞色素c氧化酶是完全活性的。当去除这些二磷脂酰甘油中的一个或多个时，酶活性就会丧失。在测定混合物中加入二磷脂酰甘油和溶血磷脂酰胆碱可获得完全激活，但不能加入磷脂酰胆碱或磷脂酰乙醇胺。直接结合实验、动力学研究以及以前使用芳基细胞色素c衍生物[Bisson，R.，Jacobs，B.&Capaldi，R.(1980)BioChemical 10,4173-4178]的工作表明，二磷脂酰甘油参与了底物细胞色素c与细胞色素c氧化酶的结合。
Isolated beef heart cytochrome c oxidase (ferrocytochrome c:oxygen oxidoreductase, EC 1.9.3.1) contains four or five molecules of tightly bound diphosphatidylglycerol per monomer (2-heme complex). This lipid could be removed in part, or wholly, by mixing the enzyme with high concentrations of Triton X-100 and then centrifuging the mixture through a glycerol gradient equilibrated in the same detergent. Cytochrome c oxidase retaining three or more diphosphatidylglycerol molecules per monomer was fully active when assayed in 1-oleoyl lysophosphatidylcholine. Upon removal of one or more of these diphosphatidylglycerols, enzymic activity was lost. Full activation could be obtained by adding diphosphatidylglycerol to the assay mixture along with lysophosphatidylcholine but not by adding phosphatidylcholine or phosphatidylethanolamine. Direct binding experiments, kinetic studies, and previous work using arylazidocytochrome c derivatives [Bisson, R., Jacobs, B. & Capaldi, R. A. (1980) Biochemistry 10, 4173-4178], indicate that diphosphatidylglycerol is involved in binding of substrate cytochrome c to cytochrome c oxidase.