科研之友
微信
新浪微博
Facebook
分享链接
摘要
Listeria monocytogenes and Cronobacter sakazakii are notorious pathogens involved in numerous food borne outbreaks after ingested contaminated food. Bacteriocins are natural food preservatives, some of which have antimicrobial activity comparable with antibiotics. In this study, a plasmid encoded novel bacteriocin BMP11 produced by Lactobacillus crustorum MN047 was innovatively identified by combining complete genome and LC-MS/MS. The BMPI1 was found to have rich alpha-helix conformation after prediction. Moreover, the antimicrobial activity of BMPI1 was verified after its heterologous expression in E. cob with 1280 and 640 ALIMIL against L monocytogenes and C sakazakii, respectively. After purification by anion-exchange chromatography and HPLC, BMP11 had MIC values of 03-38.4 mu g/mL against tested foodborne pathogens. Further, it was found that BMPII had bactericidal action mode with concomitant cell lysis to pathogens by growth curve and time-kill kinetics. The results of scanning electron microscope (SEM) and transmission electron microscope (TEM) indicated that BMP11 destroyed the integrity of cell envelope of pathogens with cell wall perforation and cell membrane permeabilization. The destruction of cell envelope integrity was further verified by propidium iodide (PI) uptake and lactic dehydrogenase (LDH) release. BMPII increased inner-membrane permeability of C. sakazakii in a concentration-dependent manner. Meanwhile, BMP11 exhibited antibiofilm formation activity. In addition, BMP11 inhibited the growth of L. monocytogenes in milk. Therefore, BMPII had promising potential as antimicrobial to control foodborne pathogens in dairy products.
- 出版日期2018-9
- 单位西北农林科技大学
