Effect of lipid composition on the calcium/adenosine 5'-triphosphate coupling ratio of the Ca2+-ATPase of sarcoplasmic reticulum.
Effect of lipid composition on the calcium/adenosine 5'-triphosphate coupling ratio of the Ca2+-ATPase of sarcoplasmic reticulum.
复制标题
脂质成分对肌浆网Ca2-ATP酶钙/腺苷5-三磷酸偶联比的影响。
DOI：
10.1021/bi00296a021
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发表时间：
1984
期刊：
影响因子：
2.9
通讯作者：
Racker,E
中科院分区：
文献类型：
--
作者：
Navarro,J;Toivio-Kinnucan,M;Racker,E
Javier Navarro、Maria Toivio-Kinnucan 和 Efraim Racker* 摘要：通过在 Triton X-100 中溶解并在 DE-52 柱上分级，纯化肌浆网的 Ca2+-ATP 酶并去除蛋白脂质。通过脱氧胆酸盐-胆酸盐透析以低脂质与蛋白质比率（2-5 毫克脂质/毫克蛋白质），用二油酰磷脂酰乙醇胺或单半乳糖基二甘油酯重建蛋白质，表现出较高的 ATP 依赖性 Ca2+ 摄取初始速率 [300-900 nmol min-1（蛋白质毫克）"1] 和耦合比（Ca2+ 转运/ATP 水解） 2. 用甲基化程度增加（二油酰磷脂酰乙醇胺、二油酰单甲基磷脂酰乙醇胺、二油酰二甲基磷脂酰乙醇胺和二油酰磷脂酰胆碱）或糖基化程度增加（单半乳糖甘油二酯和二半乳糖甘油二酯）的脂质重构Ca2+-ATP酶ATP 依赖性 Ca2+ 摄取和偶联比率均降低 随着重建囊泡中二油酰磷脂酰乙醇胺/二油酰磷脂酰胆碱或单半乳糖甘油二酯/二油酰磷脂酰胆碱摩尔比的降低，Ca2+ 摄取的速率和程度降低。0'a2+-ATPase1 肌浆网膜。该蛋白已通过多种方法纯化并重构为磷脂囊泡（Racker，1979），通过脱氧胆酸盐-胆酸盐透析进行的 Ca2+-ATP 酶重构实验表明，磷脂酰乙醇胺是 Ca2+ 吸收所必需的。 ATP 水解和 Ca2+ 转运活性可通过添加适量的硬脂酰胺或油酰胺来恢复（Knowles 等人，1975）。最近，Hidalgo 等人（1982）证明，用荧光胺阻断肌浆网囊泡中的 PE 氨基会导致 Ca2+-ATP 酶的低耦合受到抑制。 Ca2+ 依赖性 ATP 水解不受影响。
Javier Navarro, Maria Toivio-Kinnucan, and Efraim Racker* abstract: The Ca2+-ATPase of sarcoplasmic reticulum was purified and depleted of proteolipids by solubilization in Triton X-100 and by fractionation on a DE-52 column. The protein reconstituted by deoxycholate-cholate dialysis at low lipid to protein ratios (2-5 mg of lipid/mg of protein), with either dioleoylphosphatidylethanolamine or monogalactosyldi-glyceride, exhibited high initial rates of ATP-dependent Ca2+ uptake [300-900 nmol min-1 (mg of protein)" 1] and coupling ratios (Ca2+ transported/ATP hydrolyzed) up to1. 2. Ca2+-ATPase reconstituted with lipids of increasing degrees of methylation (dioleoylphosphatidylethanolamine, dioleoylmonomethylphosphatidylethanolamine, dioleoyldimethyl-phosphatidylethanolamine and dioleoylphosphatidylcholine) or increasing degrees of glycosylation (monogalactosyldiglyceride and digalactosyldiglyceride) revealed a progressive decrease in both ATP-dependent Ca2+-uptake and coupling ratios. The rate and extent of Ca2+ uptake decreased as the dioleoylphosphatidylethanolamine/dioleoylphosphatidylcholine or monogalactosyldiglyceride/dioleoylphosphatidylcholine molar ratios in the reconstituted vesicles were reduced.0'a2+-ATPase1 of sarcoplasmic reticulum membranes cou-ples the hydrolysis of ATP to Ca2+ transport. This protein has been purified and reconstitutedinto phospholipid vesicles by several methods (Racker, 1979). Reconstitution experi-ments with the Ca2+-ATPase by deoxycholate-cholate dialysis demonstrated that phosphatidylethanolamine is required for Ca2+ uptake. Reconstitution of the enzyme with acetyl-PE yielded vesicles lacking both ATP-hydrolysis andCa2+-transport activities, which were restored by addition of suitable amounts of stearoylamine or oleoylamine (Knowles et al., 1975). Recently, Hidalgo et al.(1982) demonstrated that blockage of the amino group of PE in sarcoplasmic reticulum vesicles with fluorescamine resulted in low coupling of the Ca2+-ATPase. Ca2+ transport was inhibited, but Ca2+-dependent ATP hydrolysis was unaffected. These observations