Economical Production of Recombinant Human Interleukin – 17E using Industrially Important Salt Inducible Escherichia coli GJ1158: A Fermentation Approach

Abstract

Interleukin-17E (also known as is the distinct member of Interleukin-17 cytokine family, induces the expression of . Economical production of interleukin -17E has lot of importance in the current day research in several clinical applications. The objective of the study was to optimize the physico-chemical parameters i.e., dissolved oxygen (DO) and nutritional factors i.e., carbon, nitrogen and phosphate sources on production of Interleukin-17E using industrially important salt inducible Escherichia coli GJ1158. The expression levels were not increased beyond 30 % DO in batch fermentation, but expression levels were increased beyond 30 % DO in fed-batch fermentation. The threshold level of dissolved oxygen ranges was 50 % in respect to the IL-17E production. Pulses of nutritional factors i.e., glucose, yeast extract and K 2 HPO 4 enhanced the expression levels in fed batch fermentation at 40 % and 50 % dissolved oxygen ranges. When OD 600 of the culture reaches to 74 in fed batch fermentation, culture was induced with 100 mM sterile NaCl and further incubated for next 15 hr. Purification was carried out using Ni -NTA spin column. A final concentration of 98 mg/L of purified IL-17E was obtained using cost effective medium viz., modified M9ON medium. The IL-17E thus produced is tested for its activity. In this study, fed-batch fermentation emphasizes the highest concentration of codon optimized recombinant human interleukin-17E using salt inducible expression host till to date, which manages to satisfy the industrial and clinical requirements.