Enhanced Production Of Streptokinase By Chemical Mutagenesis Of Streptococcus agalactiae EBL-20

Abstract

Streptokinase (SK) is an enzyme that is used for the treatment of cardiovascular diseases. The current study focused on the enhanced production of SK by inducing mutation in Streptococcus agalactiae EBL-20 and optimization of medium components and culture conditions for the maximum growth of mutant derived strain. S. agalactiae EBL-32 was selected as a potent mutant after exposure of S. agalactiae EBL-20 to EMS for 180 minutes. SK activity obtained from mutant derived strain was found to be 1.6 fold higher as compared to the activity achieved by wild strain. Nutritional requirements of the mutated strain were optimized by single factor analysis method suggesting glucose as the optimum carbon source; yeast extract and peptone as a suitable nitrogen sources and corn steep liquor (CSL) as an appropriate substrate for the maximum SK production. The culture conditions determined by response surface methodology (RSM) suggested that a temperature value of 37.5°C and pH 7 of the fermentation medium with 2.50 mL inoculum size for 36 hours of incubation was optimum for maximum yield of SK. Hence the optimization studies resulted into 1.92 fold increase in the yield of SK suggesting the new isolate suitable for commercial scale production of SK.