Micro-coulometric study of bioelectrochemical reaction coupled with TCA cycle

详细信息	查看全文 | 推荐本文 |

• 作者：Seiya Tsujimura^a ; ^{seiya@ims.tsukuba.ac.jp} ; Jun Fukuda^a ; Osamu Shirai^a ; Kenji Kano^a ; Hideki Sakai^b ; Yuichi Tokita^b ; Tsuyonobu Hatazawa^b
• 关键词：Tricarboxylic acid cycle ; Bioelectrocatalysis ; Coulometry ; Biofuel cell ; Bioreactor ; Diaphorase
• 刊名：Biosensors and Bioelectronics
• 出版年：2012
• 期刊代码：12_09565663
• 类别：ch
• 出版时间：15 April, 2012
• 卷：34
• 期：1
• 页码：244-248
• 文件大小：515 K

摘要

The mediated electro-enzymatic electrolysis systems based on the tricarboxylic acid (TCA) cycle reaction were examined on a micro-bulk electrolytic system. A series of the enzyme-catalyzed reactions in the TCA cycle was coupled with electrode reaction. Electrochemical oxidation of NADH was catalyzed by diaphorase with an aid of a redox mediator with a formal potential of 鈭?.15 V vs. Ag|AgCl. The mediator was also able to shuttle electrons between succinate dehydrogenase and electrode. The charge during the electrolysis increased on each addition of dehydrogenase reaction in a cascade of the TCA cycle. However, the electrolysis efficiencies were close to or less than 90%because of the product inhibition. Lactate oxidation to acetyl-CoA catalyzed by two NAD-dependent dehydrogenases was coupled with the bioelectrochemical TCA cycle reaction to achieve the 12-electron oxidation of lactate to CO₂. The charge passed in the bioelectrocatalytic oxidation of 5 nmol of lactate was 4 mC, which corresponds to 70%of the electrolysis efficiency.