Promoter optimization in the pHP49 backbone for improving the protease titer in B. pumilus Jo2.1 cultivations. Used promoters: Pref, P
apr E1 I, P
apr E1 II, P
apr E1 III, P
apr E1 IV, P
apr E2. Cultivations were carried out in the optimized fed batch fermentation process. Yielded enzyme concentrations scaled in correlation to the subtilisin BL18 protease titer of the current production host B. licheniformis/pHP49 in a lab scale cultivation serving as industrial relevant reference in this contribution. Error bars represents the standard deviation of at least three biological replicates. P
apr E2 represents the mean value of only two independent cultivations (with this promoter the two fermenter yields were essentially identical).