| 초록 |
Carbon dioxide is a major cause for the global warming. Purple non-sulfur bacteria (PNSB) can grow either heterotrophically under aerobic condition or phototrophically under anaerobic light conditions using bicarbonate or CO2 as Ci source and hydrogen or organic compounds as electron donors. Carbonic anhydrase (CA; EC 4.2.1.1) is as zinc-containing metalloenzyme catalyzing the reversible hydration of CO2. In PNSB, intracellular CA enhances the rate of CO2 to HCO3- conversion, for fixation by phosphoelpyruvate carboxylase. In this study, to highly express CA in PNSB, Rhodobacter sphaeroides was used as a recipient strain for transformation using the plasmid pBBR1mcse-2 fused with promoter puc and CA. This result showed that transformed R. sphaeroides used high concentration of CO2 and enhanced the production of physiologically activating compounds. Therefore, the inducible expression of CA in R. sphaeroides is to acceleate the conversion of CO2 to biocarbonate in the intracellular system. In addition, this study will suggest useful approach to improve CO2 fixation and photosynthetic ability in this species for a variety of biotechnological applications. |
