Munge B, Pendon Z, Frank H A, Rusling J F
Department of Chemistry, University of Connecticut, U-60, 55 North Eagleville Road, Storrs, CT 06269-3060, USA.
Bioelectrochemistry. 2001 Nov;54(2):145-50. doi: 10.1016/s1567-5394(01)00122-0.
Cyclic voltammetry of thin films made from the lipid dimyristoylphosphatidyl choline and reaction centers from the purple bacterium Rhodobacter sphaeroides on pyrolytic graphite electrodes in bromide-free pH 8 buffers at 4 degrees C revealed an oxidation peak at 0.98 V and a reduction peak at -0.17 V vs. NHE. No reverse CV peaks were found, suggesting chemical irreversibility. The reduction peak disappeared for reaction centers depleted of quinones, suggesting that the peak represents reduction of this cofactor. The oxidation peak showed a catalytic current increase in the presence of small amounts of ferrous cytochrome c, and decreased by 85% when illuminated by visible light, suggesting assignment to the primary donor (P) cofactor. While oxidized primary donor P(+) is destroyed upon electrochemical formation in the film, reaction of ferrous cyt c with P(+) suggests its persistence in the films on the microsecond time scale.
在4℃下，于无溴的pH 8缓冲液中，对由脂质二肉豆蔻酰磷脂酰胆碱和来自球形红细菌的反应中心制成的薄膜在热解石墨电极上进行循环伏安法研究，结果显示相对于标准氢电极（NHE），在0.98 V处有一个氧化峰，在-0.17 V处有一个还原峰。未发现反向循环伏安峰，表明存在化学不可逆性。对于醌耗尽的反应中心，还原峰消失，这表明该峰代表这种辅因子的还原。氧化峰在存在少量亚铁细胞色素c时显示出催化电流增加，并且在可见光照射下降低了85%，这表明该氧化峰可归属于初级供体（P）辅因子。虽然氧化的初级供体P(+)在薄膜中通过电化学形成时会被破坏，但亚铁细胞色素c与P(+)的反应表明其在薄膜中在微秒时间尺度上持续存在。
