Process Biotechnology
Electronic Journal of Biotechnology ISSN: 0717-3458 Vol. 14 No. 3, Issue of May 15, 2011
© 2011 by Pontificia Universidad Católica de Valparaíso -- Chile Received August 11, 2010 / Accepted March 7, 2011
DOI: 10.2225/vol14-issue3-fulltext-6

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

Jong-Wan Kim§1 · Jeehyun Yoe§1 · Gil Ho Lee2 · Sung Moon Yoe*1

1 Department of Biological Sciences, Dankook University, Cheonan, Korea
2 Department of Urology, College of Medicine,Dankook University,Cheonan, Korea

*Corresponding author:

§ These authors equally contributed to this work.

Financial support: The present research was conducted by the research fund from Institute of Bio-science and Technology at Dankook University in 2009.

Keywords: antibacterial activity, inclusion body, lysozyme, on-column refolding, recombinant expression, Spodoptera litura.


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.