Sucrose induces simultaneous autolysis attenuation and keratinase production enhancement in Bacillus subtilis WB600

This study investigated the inhibitory effect of sucrose on the autolysis of recombinant Bacillus subtilis WB600 during keratinase production and elucidated its mechanism. Growth curves, cell morphology observations, cell wall integrity detection, and transcriptome analysis revealed that 2 % sucrose significantly increased cell biomass and delayed autolysis. Keratinase activity reached 5670.70 ± 8.09 U/mL at 60 h of fermentation, approximately 1.3-fold higher than the control. Sucrose achieves this by reprogramming metabolism to promote cell wall peptidoglycan synthesis gene expression, remodeling the autolysin spectrum, enhancing central carbon metabolism, and boosting anti-oxidative stress capacity. These combined effects synergistically inhibit autolysis and promote keratinase production. This research offers a novel strategy for mitigating Bacillus subtilis autolysis in industrial fermentation.