表面活性剂CHAPS对紫膜脂双层微环境的作用

EFFECT OF DETERGENT CHAPS ON MICRO-SURROUNDINGSIN PURPLE MEMBRANE BILAYER

利用顺磁性自旋标记技术 ,探测在表面活性剂CHAPS(3 -[(3 -Cholamidopropyl)dimethyl-ammonio]propanesulfonicacid )作用下 ,紫膜脂双层微环境的物理参数 (序参数S和旋转相关时间τc)的变化。实验结果表明 :CHAPS的增溶过程对紫膜的表层微环境和深层微环境的影响不同。表层序参数S值随CHAPS浓度的增加而逐渐减小 ;深层旋转相关时间τc值开始随CHAPS浓度的增加而增大 ,在CHAPS浓度为5mmol/l时 ,τc值呈现最大值 ,随着CHAPS浓度的继续增大 ,τc值逐渐减小并趋近于恒定。

The physical parameters (order parameter s and rotational correlation time τc) of the purple membrane bilayer treated with detergent CHAPS, were investigated by technique of spin label. The results showed that the effects of solubilization by CHAPS on the micro-surroundings of polar surface area in purple membrane bilayer were different from that in hydrophobic inner area. The order parameter s decreased while CHAPS concentration increased. The rotational correlation time τc increased with increasing of CHAPS concentration, and reached a maximum when CHAPS concentration was 5mmol/L. With further increase of CHAPS concentration, τc decreased continually and reached a constant value.