| 초록 |
Carbonic anhydrase (CA; EC 4.2.1.1) has been considered as a biocatalyst adequate for the development of CO2 sequestration process. The high production of functional CA is required for practical CO2 sequestration application mediated by CA. Here, the synthetic gene new α type-CA (HC-aCA) of Hahella chejuensis, which was designed based on Escherichia coli codon usage, was employed for E. coli expression system. We obtained a high yield of functional HC-aCA by denaturing/refolding process and incorporating zinc ion into its active site. The refolded HC-aCA showed a half-deactivation temperature of 60°C with maximal activity at 50°C, and had high pH stability in alkali condition with maximal activity at pH 10.0. The esterase activity of HC-aCA almost doubled at high salt concentration ranging from 0.67 to 2.0 M NaCl. HC-aCA catalyzed the conversion of CO2 to CaCO3 as a calcite form in the presence of Ca2+. The refolded HC-aCA could be a potent candidate for development of efficient CO2 sequestration processes. |
