Department of Chemical Engineering, Kwangwoon University, 139-701 Seoul, Republic of Korea.
The Institute of Molecular Biology and Genetics, Seoul National University, 151-742 Seoul, Republic of Korea.
Bioresour Technol. 2015 Jun;185:35-9. doi: 10.1016/j.biortech.2015.02.086. Epub 2015 Feb 27.
The use of biocatalysts to convert CO2 into useful chemicals is a promising alternative to chemical conversion. In this study, the electro-biocatalytic conversion of CO2 to formate was attempted with a whole cell biocatalyst. Eight species of Methylobacteria were tested for CO2 reduction, and one of them, Methylobacterium extorquens AM1, exhibited an exceptionally higher capability to synthesize formate from CO2 by supplying electrons with electrodes, which produced formate concentrations of up to 60mM. The oxygen stability of the biocatalyst was investigated, and the results indicated that the whole cell catalyst still exhibited CO2 reduction activity even after being exposed to oxygen gas. From the results, we could demonstrate the electro-biocatalytic conversion of CO2 to formate using an obligate aerobe, M. extorquens AM1, as a whole cell biocatalyst without providing extra cofactors or hydrogen gas. This electro-biocatalytic process suggests a promising approach toward feasible way of CO2 conversion to formate.
利用生物催化剂将二氧化碳转化为有用的化学物质是一种有前途的化学转化替代方法。在这项研究中，使用全细胞生物催化剂尝试了电生物催化将二氧化碳转化为甲酸盐。测试了八种甲基杆菌属物种进行二氧化碳还原，其中一种，甲基杆菌extorquens AM1，通过用电极提供电子表现出异常高的从二氧化碳合成甲酸盐的能力，可产生高达 60mM 的甲酸盐浓度。研究了生物催化剂的氧气稳定性，结果表明，即使在暴露于氧气后，全细胞催化剂仍表现出二氧化碳还原活性。从结果中，我们可以证明使用专性需氧菌 M. extorquens AM1 作为全细胞生物催化剂，无需提供额外的辅因子或氢气，即可实现二氧化碳到甲酸盐的电生物催化转化。这种电生物催化过程为可行的二氧化碳转化为甲酸盐的方法提供了一种有前途的途径。
