离子强度、温度及表面活性剂Triton X-100对紫膜质子泵效率的影响  

THE EFFECT OF IONIC STRENGTH, TEMPERATURE AND NONIONIC DETERGENT ON THG QUANTUM EFFICIENCY OF THE PROTON PUMP OF PURPLE MEMBRANE

作　　者：施桦[1] 孙英[1] 谈曼琪 孙纹琦 胡坤生[1] 

机构地区：[1]中国科学院生物物理研究所,北京100101

出　　处：《生物物理学报》1992年第2期221-225,共5页Acta Biophysica Sinica

摘　　要：用毫秒级闪光动力学光谱仪研究了离子强度、温度及表面活性剂Triton X-100对紫膜质子泵效率的影响。结果表明:紫膜溶液中适量离子的加入可使其质子泵效率(H^+/M_(412))显著提高(纯水中,H^+/M_(412)—0.56,而在150mM KCl中可达—1.3),高价离子的影响显然远大于低价离子;在5℃—50℃的较大温度范围内,紫膜的质子泵效率变化不大,但当温度升至60℃以上时,紫膜的质子泵效率迅速下降直至为零;非离子表面活性剂Triton X-100的加入对紫膜的质子泵效率影响不大,仅随Triton量的增加而略微下降。以上实验现象,直接或间接地说明了离子在紫膜质子泵功能中的重要作用。就此对离子及脂在紫膜质子泵中的作用机制进行了进一步的探讨。The quantum efficiency of the proton pump of Purple Membrane (H+/M412 rato) was measured by flash kinetic spectrophotometer under varying conditions of ionic strength, temperature and nonionic detergent Triton X-100. Cations in the medium can significantly increase the quantum yield of proton pumping. But Triton X-100 has only slight effect on it. The H+/M412 ratio decreases rapidly to 0 at about 70℃, but resumes its original value with the decrease of temperature.With the results above, the discussion has been made on the function of cations and lipid in the proton pumping process of Purple Membrane.

关 键 词：离子 温度 质子泵 量子效率 紫膜 

分 类 号：Q734[生物学—分子生物学]