A sucrose-inducible promoter system for the intra- and extracellular protein production in Bacillus megaterium

A sucrose-inducible promoter system (PsacB) from Bacillus megaterium was identified using a secretome approach. It was successfully employed for the extracellular production of the homologous levansucrase SacB (4252.4 U l−1) and the heterologous green fluorescent protein GFP (7.9 mg gCDW−1). Mutational analysis of B. megaterium PsacB allowed the identification of important promoter elements. The sucrose-inducible promoter provides a useful alternative to the established xylose-inducible promoter system (PxylA) for recombinant gene expression in B. megaterium.