| 초록 |
CO2 causes global warming and climate change and thus recent researches have focused on producing useful chemicals from CO2. Among chemicals that can be obtained from CO2, formate is emerging due to its high energy density and versatility in various industries. Accordingly, CO2 conversion to formate is of our interest. Herein, we aimed to characterize formate dehydrogenase from Rhodobacter aestuarii (RaFDH) as a newly discovered CO2 reductase. RaFDH was successfully expressed in E. coli and highly concentrated recombinant was obtained, about 2.5 mg from 300 mL culture. Then, optimum condition, effect of KNO3 on RaFDH stability and kinetic constants were examined. As a result, RaFDH-driven CO2 reduction was optimized at pH 7 and 30 ℃. KNO3 has a positive effect on the RaFDH stability, thereby retaining 50.5 % of its initial activity over 216 hours when adding 10 mM of KNO3. Previously reported FDHs interconverting CO2 and formate reversibly prefered formate oxidation to CO2 reduction, but RaFDH-driven CO2 reduction far surpassed formate oxidation. Consequently, RaFDH discussed in this study can be a promising alternative for biocatalytic CO2 reduction to produce formate. |
