Recombinant expression and refolding of the c-type lysozyme from Spodoptera litura in E. coli

Abstract

The chicken-type lysozyme of the insect Spodoptera litura (SLLyz) is a polypeptide of 121 amino acids containing four disulfide bridges and 17 rare codons and participates in innate defense as an anti-bacterial enzyme. The recombinant S. litura lysozyme (rSLLyz) expressed as a C-terminal fusion protein with glutathione S-transferase (GST) in Rosetta(DE3) Singles. The protein was produced as an inclusion body which was solubilized in 8 M urea, renatured by on-column refolding, and purified by reversed-phase chromatography to 95% purity. The purified rSLLyz demonstrated antibacterial activity against B. megaterium confirmed by inhibition zone assay. The overexpression and refolding strategy described in this study will provide a reliable technique for maximizing production and purification of proteins expressed as inclusion bodies in E. coli.

Applications of Lysozyme, an Innate Immune Defense Factor, as an Alternative Antibiotic

“…Additionally, the lysozyme c-1 of Anopheles gambiae , in the course of its characterization, inhibited the growth of M. luteus but not of E. coli [ 56 ]. The possibility of cloning and overexpressing the lysozyme of Spodoptera litura in E. coli offers a method for the production of the biologically active c-type lysozyme as a natural antibiotic [ 57 , 58 ]. The same authors applied a similar process to the overexpression of lysozyme from Agrius convolvuli obtaining a peptide active against B. megaterium and M. luteus [ 59 ].…”