| 초록 |
Carbon monoxide dehydrogenase (CODH), which is a key enzyme in CO metabolism, usually catalyzes the oxidation of CO to CO2. CO is used as a carbon source to produce value-added organic compounds as metabolite in some microorganisms. To utilize CODH in a two stage biocatalytic CO-conversion system (CO-CO2-formate), ChCODH which originates from Carboxydothermus hydrogenoformans was manufactured in metabolically engineered Escherichia coli under anaerobic condition. However, this heterologous enzyme is vulnerable to produce soluble recombinant proteins because of inclusion body formation. First, the chaperone protein was introduced in metabolically engineered E. coli for decreasing formation of inclusion body and increasing the soluble expression of ChCODH with high activity. Second, various promoters (pBAD, pT7, Pzt-1) were tested to induce chaperone proteins in metabolically engineered E. coli, and the soluble expression level and activity of ChCODH were compared. As a result, we have confirmed that soluble expression and activity of ChCODH were dramatically increased by the co-expression of the chaperone proteins using the pT7 promoter. |
