Effects of degU32(Hy), degQa and degR pleiotropic regulatory genes on the growth and protease fermentation of Bacillus subtilis Ki-2-132.

Effects of degU32 (Hy), degR genes from Bacillus subtilis 168 and degQa gene from Bacillus amyloliquefaciens on Bacillus subtilis Ki-2-132 cell growth, sporulation and protease fermentation were investigated by introducing these genes into B. subtilis Ki-2-132 chromosome and/or cytoplasm. Although the genes come from different species and strains, they showed pleiotropic effects in B. subtilis Ki-2-132. B. subtilis Ki-2-132degU32 (Hy) showed increased protease production, and when cooperating with degQa either in plasmid or in chromosome, further altered cell growth, increased protease production and affected the spore formation in a glucose and dosage dependent manner. By contrast, degR did not significantly affect the protease productivity in degU32 (Hy) mutant, consisting with that DegR was used to stabilise DegU-phosphate, which in degU32 (Hy) strain no longer further amplify the DegU-phosphate effect.