Hamamoto T, Carrasco N, Matsushita K, Kaback H R, Montal M
Proc Natl Acad Sci U S A. 1985 May;82(9):2570-3. doi: 10.1073/pnas.82.9.2570.
Turnover of o-type cytochrome oxidase purified from Escherichia coli and reconstituted into proteoliposomes leads to the generation of a transmembrane electrical potential (interior negative) by means of vectorial electron flow. In the experiments reported here, purified oxidase is reconstituted in planar lipid bilayers formed at the tip of patch pipets, and open-circuit membrane potentials generated by electron transfer are measured directly. Potentials of up to 4 mV (substrate side positive) are generated in the presence of reduced phenazine methosulfate or ubiquinol-1, and with both substrates, electrogenic activity is inhibited by cyanide. Furthermore, the membrane potential generated during oxidase turnover is inhibited progressively with applied voltages (substrate side positive), decreasing almost to zero at an applied voltage of 150 mV.
从大肠杆菌中纯化并重组到蛋白脂质体中的o型细胞色素氧化酶的周转，通过矢量电子流导致跨膜电势的产生（内部为负）。在本文报道的实验中，纯化的氧化酶被重组到在膜片吸管尖端形成的平面脂质双层中，并直接测量由电子转移产生的开路膜电势。在存在还原型吩嗪硫酸甲酯或泛醇-1的情况下会产生高达4 mV的电势（底物侧为正），并且对于这两种底物，产电活性均被氰化物抑制。此外，氧化酶周转过程中产生的膜电势会随着施加电压（底物侧为正）而逐渐受到抑制，在施加电压为150 mV时几乎降至零。
