Expression and Characterization of Codon-Optimized Carbonic Anhydrase from Dunaliella Species for CO2 Sequestration Application

Abstract

Carbonic anhydrases (CAs) have been given much attention as biocatalysts for CO(2) sequestration process because of their ability to convert CO(2) to bicarbonate. Here, we expressed codon-optimized sequence of α-type CA cloned from Dunaliella species (Dsp-aCAopt) and characterized its catalyzing properties to apply for CO(2) to calcite formation. The expressed amount of Dsp-aCAopt in Escherichia coli is about 50 mg/L via induction of 1.0 mM isopropyl-β-D-thiogalactopyranoside at 20 °C (for the case of intact Dsp-aCA, negligible). Dsp-aCAopt enzyme shows 47 °C of half-denaturation temperature and show wide pH stability (optimum pH 7.6/10.0). Apparent values of K (m) and V (max) for p-nitrophenylacetate substrate are 0.91 mM and 3.303 × 10(-5) μM min(-1). The effects of metal ions and anions were investigated to find out which factors enhance or inhibit Dsp-aCAopt activity. Finally, we demonstrated that Dsp-aCAopt enzyme can catalyze well the conversion of CO(2) to CaCO(3), as the calcite form, in the Ca(2+) solution [8.9 mg/100 μg (172 U/mg enzyme) with 10 mM of Ca(2+)]. The obtained expression and characterization results of Dsp-aCAopt would be usefully employed for the development of efficient CA-based system for CO(2)-converting/capturing processes.

Biomineralization process of CaCO3 precipitation induced by Bacillus mucilaginosus and its potential in bacteria-based self-healing concrete

“…9. In the whole process of microbial induced calcium carbonate precipitations (MICP), the speci c steps of carbonic anhydrase produced by microorganisms to promote the formation of enzymatic ions and the deposition of mineralized products were as follows [40,44,45]:…”

Microbial Carbonic Anhydrases in Biomimetic Carbon Sequestration for Mitigating Global Warming: Prospects and Perspectives

“…α–CA from Dunaliella sp. produced 8.9 mg of calcite per 100 μg (172 U/mg) of enzyme in presence of 10 mM Ca 2+ (Kanth et al, 2012 ). Another thermo-alkali-stable γ–CA (ApCA) from polyextremophilic bacterium A. pallidus was used for biomineralization and well faceted rhombohedral calcite crystals were observed when viewed under scanning electron microscopy (SEM; Figure 1 ).…”

“…Codon optimization also results in faster translation rates. α–CA from Dunaliella species was codon optimized and effectively expressed in E. coli , which was used for biosequestration of CO 2 (Kanth et al, 2012 ). A synthetic α–CA ( HC-aCA ) from Hahella chejuensis was cloned and expressed (Ki et al, 2013 ).…”

Carbonic anhydrase: Its biocatalytic mechanisms and functional properties for efficient CO2 capture process development

“…In some sense, biomimetic synthesis of CaCO 3 materials using CA is a kind of carbon capture and use (CCU) technology [72][73][74][75]. The major product of CaCO 3 mediated by CA is calcite form.…”