Rapid Gene Cloning, Overexpression and Characterization of a Thermophilic Catalase in E. coli
A thermophilic catalase-encoding gene was rapidly obtained by means a PCR-based protocol with the genomic DNA mixture from compost culture as the template. The open reading frame of this gene is composed of 2208 base pairs, sharing 92.5% homology with the reported Bacillus stearothermophilus gene (NCBI genbank accession No. AB020234. 1). A prokaryotic expression plasmid pET-CATHis was constructed for the gene expression, and two recombinant E. coli, BL21(DE3)/pET-CATHis and BL21(DE3)pLysS/pET-CATHis were finally obtained. After culture optimization, the highest activities for these two strains in shaking flask culture were 74.3 U/ml and 1055.3 U/ml, respectively. The 6 His-tagged recombinant catalase was then purified by using immobilized metal affinity chromatography, and the properties of the purified protein were finally characterized.
H. Luo et al., "Rapid Gene Cloning, Overexpression and Characterization of a Thermophilic Catalase in E. coli", Advanced Materials Research, Vol. 365, pp. 367-374, 2012