细胞色素C/心磷脂相互作用的Langmuir-Blodgett膜界面特性研究  

The interfacial characteristic of mixed Cytochrome C/Cardiolipin Langmuir-Blodgett monolayer

作　　者：李俊花[1] 孙润广[1] 郝长春[1] 王娟[1] 张蕾[1] 逯晓龙 

机构地区：[1]陕西师范大学物理学与信息技术学院生物物理与生物医学工程研究室,西安710062

出　　处：《中国科学：化学》2015年第10期1065-1074,共10页SCIENTIA SINICA Chimica

基　　金：国家自然科学基金(21402114);陕西省自然科学基础研究计划(2012JQ1002);中央高校基本科研业务费专项(GK201402010)资助

摘　　要：心磷脂(CL)是真核细胞线粒体内膜中的主要磷脂之一.细胞色素C(Cyt c)是线粒体内膜呼吸链的必要成分,与许多疾病有关.本文采用Langmuir-Blodgett技术结合原子力显微镜(AFM)研究了不同量的Cyt c与CL单层膜相互作用的特性.结果表明,Cyt c在CL单层膜上吸附量存在阈值.单层膜在5、10 m N/m膜压时经历压缩扩张循环后,界面分子几乎无损失,但是在20 m N/m膜压时,界面分子出现损失.通过Volmer理论模型定量计算界面分子损失的数量,发现当Cyt c分别为0、2.5、5μL时,界面损失的分子占总分子数的1/1000,当Cyt c分别为10、15μL时,界面损失的分子数占总分子数的1/100.线粒体内膜中Cyt c的缺失或释放会引起某些疾病.因此,探究不同量Cyt c和CL之间的相互作用机理可为线粒体异常引起的疾病提供重要的信息.Cardiolipin （CL） is one of main phospholipids in the inner membrane of eukaryotic cell mitochondrion. Cytochrome c （Cyt c） is an essential component of the inner mitochondrial respiratory chain. In this work, Langmuir-Blodgett monolayer technique combined with atomic force microscopy （AFM） was used to study the interaction between different amount of Cyt c and CL monolayer at air-buffer interface. It indicates that there is a threshold value of the adsorption quantity of Cyt c on CL monolayer. The hysteresis curves indicate that the molecules of the monolayer have almost no loss at the air-buffer interface after the compression-expansion cycle under a low pressure of 5, 10 mN/m. However, the expansion curves lag the compression curves under a high pressure of 20 mN/m. With the increment of Cyt c, the hysteresis phenomenon is more and more obvious, the number of losing molecules also increased. The Volmer theoretical model was also introduced to quantitatively calculate the amount of interfacial molecular loss. When the amount of Cyt c is 0, 2.5, 5 μL, the number of losing molecules only accounts for 1/1000 of the total molecules; but the amount of Cyt c is 10, 15 μL, the number of losing molecules accounts for 1/100 of the total molecules. This work provides important information for researching some diseases caused by abnormal mitochondrion.

关 键 词：细胞色素C 心磷脂 单层膜 原子力显微镜 理论分析 

分 类 号：R363[医药卫生—病理学]