Molecular cloning and heterologous expression of lipase gene from Pseudomonas aeruginosa in Escherichia coli.

Abstract

Lipases, enzymes that perform the hydrolysis of triglycerides into fatty acids and glycerol, present a potential paradigm shift in the realms of food and detergent industries. Their enhanced efficiency, energy conservation and environmentally friendly attributes make them promising substitutes for chemical catalysts. Motivated by this prospect, this present study was targeted on the heterologous expression of a lipase gene, employing E. coli as the host organism. The lipase gene was sourced from Pseudomonas aeruginosa genomic DNA open reading frame spanning 936 bp by PCR using gene-specific primers. Initial cloning into the T/A vector (pTZ57 R/T) and subsequent sub-cloning into the pET-28a(+) bacterial expression vector. Transformation into E. coli BL21 codon plus strain ensued for the expression of the recombinant protein which was induced at 37 °C. The recombinant lipase protein was purified by immobilized metal ion chromatography. The Optimal activity of the recombinant enzyme was found to be at 40 °C and pH 8.0. The partial purified lipase exhibited a specific activity of 6595.71 U/mg in the dialyzed fraction, markedly surpassing the crude fraction's 1182.87 U/mg.