Efficient carbon dioxide sequestration by using recombinant carbonic anhydrase. (October 2018)

• Record Type: Journal Article
• Authors: Tan, Shih-I; Han, Yin-Lung; Yu, You-Jin; Chiu, Chen-Yaw; Chang, Yu-Kaung; Ouyang, Shoung; Fan, Kai-Chun; Lo, Kuei-Ho; Ng, I-Son
• Is Part Of: Process biochemistry. Volume 73(2018)
• Page Start: 38
• Page End: 46
• Publication Date: 2018-10
• Subjects: Carbonic anhydrase -- CO2 fixation -- Sequestration -- Kinetic analysis -- Immobilization; Biochemical engineering -- Periodicals; Biotechnology -- Periodicals; Biochemistry -- periodicals; Biotechnology -- periodicals; Chemical Engineering -- periodicals; Génie biochimique -- Périodiques; Biotechnologie -- Périodiques; Biochemical engineering; Biotechnology; Periodicals; 660.63
• DOI: 10.1016/j.procbio.2018.08.017
• Languages: English
• ISSNs: 1359-5113

Abstract

Graphical abstract: Highlights: The recombinant carbonic anhydrase (CA) production is up to 5 g/L in E. coli . Whole cell biocatalyst has great potential due to its stability is over 40 days. Diffusion theory is first used to calculate the effective diffusivity coefficient. Agar-immobilized CA is applied for CO2 mineralization in a two-column system. Abstract: Efficient biological carbon dioxide sequestration for slowing down the climate changes requires a highly active and stable carbonic anhydrase (CA). A CA from Mesorhizobium loti (i.e., Ml CA) was first over-expressed in E. coli via different vectors and a concentration of up to 5 g/L was obtained with pET32a(+). The whole cell biocatalyst was stable between pH 4.0 and pH 9.0 and maintained 82% activity within 6% salinity. The cations NH4 +, K +, Na +, Mg 2+, Ca 2+ and Mn 2+ did not affect the catalytic activity, while Co 2+, Cu 2+, and Zn 2+ inhibited >70% biocatalyst activity at 5 mM. The Kcat and Km of whole cell CA was observed to be 1.76 × 10 6 /s and 0.0133 mM, while that of the crude enzyme was of 2.35 × 10 6 s −1 and 0.0364 mM, respectively. The effective diffusivity coefficient ( De ) of whole cell CA was 3.98 μ m 2 /s. Whole cell biocatalyst immobilized in 2% ( w/v) agar could be reused for 6 times for CO2 sequestration and remained stable for 40 days. A novel two-column system with immobilized whole cell biocatalyst and recombinant Ml CA effectively converted 100% CO2 to CaCO3 within 3.5 min. This provides an alternative, eco-friendly and low-cost process for carbon capture and storage (CCS) in the future.