Heterologous expression of potential bacteriocin in Bacillus velezensis CM7-4 in Escherichia coli

Abstract Background Bacteriocins are peptides produced by bacteria that have antibacterial effects on other bacterial species. They have emerged as novel antimicrobial alternatives or feed additives in the field of veterinary medicine. Heterologous expression systems have been demonstrated to be capable of high-level expression of bacteriocins when bacteriocins are used in commercial and industrial contexts. Results The bacteriocin amylocyclicin was expressed in Escherichia coli BL21 (DE3), and the induction conditions were optimized by a single-factor method. The composition of the induction medium was optimized using response surface methodology (RSM). The induction conditions that yielded optimal results were an isopropylthio-β-galactopyranoside (IPTG) concentration of 0.5 mM, an induction temperature of 28 ℃, and an induction time of 6 h. The optimal sucrose, ethanol, and NaCl additions were 0.804 g/100 mL, 1.547%, and 0.809 g/100 mL, respectively. Conclusions The bacteriocin amylocyclicin was identified in the genome of Bacillus velezensis CM7-4 by BAGEL 4 and was successfully heterologous expressed in E. coli BL21 (DE3). The cultivation conditions and culture medium components were optimized. These findings contribute to the research and biotechnological production of bacteriocins, and to the development of novel antimicrobial drugs in veterinary medicine.