Production of recombinant mouse beta-interferon

A plasmid was constructed to express a mouse beta-interferon (IFN-beta) in Escherichia coli under the control of the modified tryptophan (trp) promoter. E. coli carrying the plasmid were cultivated in a minijar fermentor and synthesized up to 2.7 X 10(6) IU/ml of antiviral activity. At the end of the cultivation the cells became elongated and curved.