Peguin S, Soucaille P
Centre de Bioingénierie Gilbert Durand, Institut National des Sciences Appliquées, Toulouse Cédex, France.
Biotechnol Bioeng. 1996 Aug 5;51(3):342-8. doi: 10.1002/(SICI)1097-0290(19960805)51:3<342::AID-BIT9>3.0.CO;2-D.
The metabolism of Clostridium acetobutylicum was manipulated in chemostat culture at pH 5 and 6.5 in a three-electrode potentiostatic system with methyl viologen (MV) as the electron carrier. When a constant potential was applied at pH 5, the broth redox potential continuously decreased and, simultaneously, a high increase in the reduced MV concentration (MV(+.)) and the specific rate of butanol production was observed while butyric acid was taken up. A linear relationship was reported between the specific rate of NAD(P)(+) reduction by ferredoxin-NAD(P)(+) reductase and the broth redox potential, as long as the growth rate was not affected. To reach a steady state in glucose limited culture, a control system of the redox potential was required. However, it seems that C. acetobutylicum is able to adapt its metabolism when the broth redox potential was regulated at low value. On the other hand, at pH 6.5, the current generated by the electrochemical device had no effect either on broth redox potential and MV(+.) concentration or on the metabolism.
在以甲基紫精（MV）作为电子载体的三电极恒电位系统中，在pH值为5和6.5的条件下，对丙酮丁醇梭菌在恒化器培养中的代谢进行了调控。当在pH值为5时施加恒定电位，发酵液的氧化还原电位持续下降，同时，观察到还原态MV浓度（MV(+)）和丁醇产生比速率大幅增加，而丁酸被消耗。据报道，只要生长速率不受影响，铁氧化还原蛋白-NAD(P)(+)还原酶还原NAD(P)(+)的比速率与发酵液氧化还原电位之间呈线性关系。为了在葡萄糖受限培养中达到稳态，需要一个氧化还原电位控制系统。然而，当发酵液氧化还原电位被调节到较低值时，丙酮丁醇梭菌似乎能够适应其代谢。另一方面，在pH值为6.5时，电化学装置产生的电流对发酵液氧化还原电位、MV(+)浓度或代谢均无影响。
