Boheim G, Benz R
Biochim Biophys Acta. 1978 Feb 21;507(2):262-70. doi: 10.1016/0005-2736(78)90421-2.
Charge-pulse relaxation studies with the alamethicin-lipid membrane system reveal a triphasic decay of membrane voltage. At short times (resolution time 2 microseconds), where a voltage decay due to the orientation of alamethicin dipoles from the interface into the membranes interior ("gating current") could possibly be expected, only a slow decrease with a time constant determined by the bare membrane conductance occurs. After approximately 1 ms (depending on the experimental conditions) the formation of alamethicin pores starts, leading to an increase in the voltage decay rate. When the characteristic voltage Vcpc is approached, pores close and after passing Vcpc the voltage decreases slowly again according to the bare membrane conductance. Vcpc is determined as a function of the initially applied voltage Vo, alamethicin and KCl concentration. Since the membrane voltage decreases continuously, the system does not reach the equilibrium states obtained at constant voltages. Taking the presented experimental results into account the estimate of the electrical potential at the functional membrane of photosynthesis induced by a saturating single turnover flash of deltaphio approximately 105-135 mV (Zickler, Witt and Boheim (1976) FEBS Lett. 66, 142-148) is changed to deltaphio approximately 200 mV.
用阿拉霉素 - 脂质膜系统进行的电荷脉冲弛豫研究揭示了膜电压的三相衰减。在短时间内（分辨时间为2微秒），由于阿拉霉素偶极子从界面进入膜内部的取向（“门控电流”）可能会导致电压衰减，然而此时仅出现由裸膜电导决定时间常数的缓慢下降。大约1毫秒后（取决于实验条件），阿拉霉素孔开始形成，导致电压衰减速率增加。当接近特征电压Vcpc时，孔关闭，在超过Vcpc后，电压又根据裸膜电导再次缓慢下降。Vcpc是作为初始施加电压Vo、阿拉霉素和KCl浓度的函数来确定的。由于膜电压持续下降，该系统未达到在恒定电压下获得的平衡状态。考虑到所呈现的实验结果，由饱和单周转闪光诱导的光合作用功能膜处的电势估计值，即约105 - 135 mV（齐克勒、维特和博海姆（1976年），《欧洲生物化学学会联合会快报》66，142 - 148），变为约200 mV。
