【摘要】 用荧光标记物1,8-AMS与紫膜结合,测量了能化态和非能化态下紫膜表面电位随介质pH的变化.在pH5.5以下,紫膜表面电位随pH的降低而下降,但囊泡中的紫膜表面电位变化幅度较大;在pH5.5以上,处于非能化态的紫膜(无论是紫膜碎片还是处于囊泡中)的表面电位都没有明显变化,处于能化态时,紫膜碎片的表面电位在pH9.2出现一个峰.更多还原

【Abstract】 The pH-dependence of the surface potential of energized and nonenergized bacteriorhodopsin (bR) has been determined with the qinding of fluorescence probe 1,8-ANS to purple membrane (PM). When pH<5.5, the surface potential of PM decreases according to the decrease of pH. But the change of the surface potential was larger in vesicles. When pH>5.5, the surface potential of nonenergized PM (either in fragments or in vesicles) was a constant. In energization, there was a peak of the surface potential of PM fragment at pH9.2.更多还原