Biofilm fermentation of iturin A by a recombinant strain of Bacillus subtilis 168.

Bacillus subtilis 168 produces thin and fragile biofilm in the static culture, however, it was found out that its transformant B. subtilis RM/iSd16 containing wild sfp, itu operon and degQ, which produced lipopeptide antibiotic iturin A, produced thick and much stable biofilm. Production of iturin A by RM/iSd16 in biofilm was almost two times higher compared to that in the submerged culture at 28 degrees C.