Double-stranded RNA production and the kinetics of recombinant Escherichia coli HT115 in fed-batch culture.

Double-stranded RNA can induce interference processes. The specificity of this system raises the possibility of using dsRNA for therapeutic applications targeting viral diseases. Escherichia coli HT115 (DE3) has been widely used to produce dsRNA; however, the kinetics of dsRNA production and the relationship between dsRNA and biomass remain unknown. Our aims were to study the kinetics of dsRNA production and to improve dsRNA productivity with fed-batch technology. The results revealed that the production of dsRNA was growth-associated. In batch fermentation, the dsRNA/biomass yield remained close to 0.06 g·g-1 , with a maximum productivity of 11.1 mg l-1  h-1 at 10 h of culture. In fed-batch fermentation, the yield was 0.06 g g-1 , with a maximum dsRNA productivity of 15.2 mg l-1  h-1 at the end of the feed (12 h). Therefore, to increase the production of dsRNA, it is necessary to enhance the biomass that produces the recombinant nucleic acid.