Kinetics and mechanism of phosphatidylcholine and cholesterol exchange between single bilayer vesicles and bovine serum high-density lipoprotein.
Kinetics and mechanism of phosphatidylcholine and cholesterol exchange between single bilayer vesicles and bovine serum high-density lipoprotein.
复制标题
单双层囊泡与牛血清高密度脂蛋白之间磷脂酰胆碱和胆固醇交换的动力学和机制。
DOI：
10.1021/bi00576a014
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发表时间：
1979
期刊：
影响因子：
2.9
通讯作者：
G. Maine
中科院分区：
文献类型：
--
作者：
A. Jonas;G. Maine
Ana Jonas**和Gregory T.Maine摘要：我们研究了含有卵磷脂酰胆碱和胆固醇的摩尔比为2：1的超声处理的单层双层囊泡与牛血清高密度脂蛋白之间的脂交换，没有卵磷脂胆固醇酰基转移酶的活性。然后将标记的脂泡([，4C]胆固醇和[~3H]-磷脂酰胆碱)与脂蛋白(与多余的未标记的囊泡预平衡)在37℃恒温下孵育，并在5℃的SepharoseCL-4B柱上分离反应混合物。根据放射性同位素交换处理，将出现在脂蛋白洗脱峰中的放射性标记脂质随时间的比例用于动力学分析。结果表明，在我们的实验条件下，没有脂类的净转移。所有囊泡胆固醇都是可交换的，放射性标记交换半衰期为1小时8分钟。相比之下，只有69%的囊泡磷脂酰胆碱与高密度脂蛋白交换，
Ana Jonas** and Gregory T. Maine abstract: We investigated the exchange of lipids between sonicated, single bilayer vesicles containing egg phosphatidylcholine and cholesterol in a molar ratio of 2: 1 and bovine serum high density lipoprotein, free of lecithimcholesterol acyltransferase activity. Lipid exchange was followed by incubating radiolabeled vesicles ([, 4C] cholesterol and [3H]-phosphatidylcholine) with the lipoprotein (preequilibrated with excess unlabeled vesicles) at a constant temperature of 37 C and by fractionating the reaction mixtures on Sepharose CL-4B columns at 5 C. The proportion of radiolabeled lipid appearing in the lipoprotein elution peak, with time, was used in the kinetic analysis based on the radioisotope exchange treatment. Results indicate that there is no net transfer of lipids under our experimental conditions. All of the vesicle cholesterol is exchangeable, with a radiolabel exchange half-life of 1 h 8 min. In contrast, only 69% of the vesicle phospha-tidylcholine exchanges with the high density lipoprotein,