Expression and characterization of codon-optimized carbonic anhydrase from Dunaliella species for CO(2) sequestration application.
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.
Department of Biotechnology and Bioinformatics, Korea University, Jochiwon, Chungnam 339-700, South Korea.
Bashistha Kumar
BK
Kanth
Kiha
K
Min
Shipra
S
Kumari
Hancheol
H
Jeon
Eon Seon
ES
Jin
Jinwon
J
Lee
Seung Pil
SP
Pack
D000595:Amino Acid Sequence; D001483:Base Sequence; D002245:Carbon Dioxide / Q000378:metabolism*; D002256:Carbonic Anhydrases / Q000737:chemistry* / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D000460:Chlorophyta / Q000201:enzymology* / Q000235:genetics; D003062:Codon; D004795:Enzyme Stability; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D007700:Kinetics; D008969:Molecular Sequence Data; D015202:Protein Engineering
D003062:Codon; D002245:Carbon Dioxide; D002256:Carbonic Anhydrases