Optimization and High Level Production of Recombinant Synthetic Streptokinase in <i>E. coli</i> Using Response Surface Methodology

Abstract

Streptokinase (SK) is an extracellular protein comprising 414 amino acids with considerable clinical importance as a commonly used thrombolytic agent. Due to its wide spread application and clinical importance designing more efficient SK production platforms worth investigation. In this regard, a synthetic SK gene was optimized and cloned in to pET21b plasmid for periplasmic expression. Response surface methodology was used to design a total of 20 experiments for optimization of IPTG concentration, post-induction period, and cell density of induction (OD600). The optimum levels of the selected parameters were successfully determined to be 0.28 mM for IPTG concentration, 9.889 H for post induction period, and 3.40768 for cell density (OD600). These settings result in 4.14fold increase in SK production rate of optimum expression conditions (7663 IU/mL) in comparison to the primary expression conditions (1853 IU/mL). Achieving higher yields of SK production in shake flask could lead to more cost effective industrial production of this drug which is the ultimate aim of SK production studies.