Expression, Purification And Characterization Of Recombinant Serratia Marcescens Nuclease

The expression gene of Serratia marcescens nuclease (strain SM6) is constructed to vector SMnucA-p ET43.1a according to the amino acid sequence. The expression vector SMnucA-p ET43.1a is transformed into E. coli BL21 (DE3) and SMnucA protein is expressed as inclusion bodies under IPTG induction. After purification, the enzyme is refolded. It is shown in the SDS-PAGE analysis that the relative molecular mass of SMnucA is 26 kD which is consistent with the theoretical predicted weight. The enzymatic activity of the refolded Serratia marcescens nuclease is confirmed through DNA degradation experiment. The enzymatic activity is consistant with that in the publication.