Optimization of the Fermentation Conditions of Pep-1-Fused EGF in Escherichia coli

Abstract

Human epidermal growth factor (hEGF), a well-known polypeptide agent which has been widely used in the medicine and cosmetics, is a 6.2 kDa single-chain polypeptide consisting of 53 amino acids. Here, to enhance its transmembrane ability, a recombinant EGF fused with Pep-1, a cell-penetrating peptides (CPP) that has been previously shown to be powerful transport vector tool for the intracellular delivery of a variety of cargos through the cell membrane, was expressed in Escherichia coli. Furthermore, The expression conditions was optimized, and the results showed that the Pep-1-fused EGF (P-EGF) could be successfully expressed in E. coli BL21-TrixB (DE3) using an expression vector, pGEX-6P-3, which contains a GST tag. The recombinant product reached the highest soluble expression when the expression strain was induced by 0.2 mmol/l IPTG and cultivated at the temperature of 20 °C with a rotation speed of 200 rpm for 8 h.