Fed-batch production of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) in soluble form in Escherichia coli and its purification and characterization

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising anticancer agent. The aim of this study is to produce large quantities of highly pure and bioactive recombinant human TRAIL. Here, TRAIL was expressed in soluble form by pH-stat fed-batch cultivation and purified using a rapid and simple two-step chromatographic procedure. To improve the soluble yield, expression of TRAIL in Escherichia coli was induced with low IPTG concentration (0.1 mM) at low temperature (28 degrees C) supplemented with ZnSO4 (0.5 mM), using glycerol as carbon source. Under the optimized conditions, 4.14 +/- 0.19 g/L of TRAIL in soluble form was achieved at 19 h without pure oxygen. To purify the recombinant TRAIL, we developed an efficient two-step chromatographic procedure including affinity chromatography and cation-exchange chromatography, especially improved the cation-exchange chromatography using a combination of pH and NaCl gradients strategy. Consequently, 4313.5 mg of target protein with high purity (98.1%) was obtained from 2.3 L of cell broth. Our results also showed that the purified TRAIL was with ordered secondary and tertiary structures, in homogeneous form and with strong cytotoxicity. (C) 2016 Published by Elsevier Inc.