Heterologous expression and purification of active divercin V41, a class IIa bacteriocin encoded by a synthetic gene in Escherichia coli.

Divercin V41, a class IIa bacteriocin with strong antilisterial activity, is produced by Carnobacterium divergens V41. To express a recombinant version of divercin V41, we constructed a synthetic gene that encodes the mature divercin V41 peptide and then overexpressed the gene in pET-32b by using the T7 RNA polymerase promoter in the Escherichia coli Origami (DE3)(pLysS) strain. The DvnRV41 peptide was expressed as a translational fusion protein with thioredoxin and accumulated in the cell cytoplasm in a soluble anti-Listeria active form. The fusion protein was then purified and cleaved to obtain pure, soluble, folded DvnRV41 (462 microg per 20 ml of culture). This paper describes the first design of a synthetic bacteriocin gene and the first bacteriocin expressed in the E. coli cytoplasm.