Ma Haotian, Ding Yuexia, Peng Jinju, Li Yang, Pan Ruixue, Long Yuner, Zhao Yining, Guo Rongxian, Ma Yi
College of Coastal Agricultural Sciences, Guangdong Ocean University, Zhanjiang 524088, China.
Laboratory of Functional Microbiology and Animal Health, Luoyang Key Laboratory of Live Carrier Biomaterial and Animal Disease Prevention and Control, College of Animal Science and Technology, Henan University of Science and Technology, Luoyang 471003, China.
Microbiol Res. 2025 Jan;290:127980. doi: 10.1016/j.micres.2024.127980. Epub 2024 Nov 22.
Listeria monocytogenes, a pathogenic bacterium causing zoonotic diseases, necessitates the urgent search for novel anti-Listeria monocytogenes drugs due to the continuous emergence of drug-resistant bacteria. In this study, we isolated and identified a bacteriocin-producing strain CM7-4 from seawater as Bacillus velezensis through 16S rRNA sequence analysis. Moreover, we successfully purified a novel bacteriocin named PCM7-4 from Bacillus velezensis CM7-4. The molecular weight of PCM7-4 was determined to be 40,228.99 Da. Notably, PCM7-4 exhibited broad-spectrum antibacterial activity against both Gram-positive and Gram-negative bacteria with a minimum inhibitory concentration (MIC) of 5.625 μg/mL against Listeria monocytogenes specifically. It demonstrated heat resistance and high stability within the pH range of 2-12 while being sensitive to proteinase K degradation without any observed hemolytic activity. Furthermore, SEM analysis revealed that PCM7-4 effectively inhibited biofilm formation and disrupted cell membranes in Listeria monocytogenes cells. Transcriptome analysis revealed that PCM7-4 exerts an impact on genes associated with crucial metabolic pathways, encompassing the biosynthesis of secondary metabolites, phosphotransferase systems (PTS), and starch/sucrose metabolism. These findings highlight the significant potential of bacteriocin PCM7-4 for the development of effective antimicrobial interventions targeting food-borne pathogenic bacteria.
单核细胞增生李斯特菌是一种可导致人畜共患病的致病细菌，由于耐药菌的不断出现，迫切需要寻找新型抗单核细胞增生李斯特菌药物。在本研究中，我们通过16S rRNA序列分析从海水中分离并鉴定出一株产细菌素的菌株CM7-4为贝莱斯芽孢杆菌。此外，我们成功地从贝莱斯芽孢杆菌CM7-4中纯化出一种新型细菌素PCM7-4。PCM7-4的分子量测定为40228.99 Da。值得注意的是，PCM7-4对革兰氏阳性菌和革兰氏阴性菌均表现出广谱抗菌活性，对单核细胞增生李斯特菌的最低抑菌浓度（MIC）为5.625 μg/mL。它表现出耐热性，在pH值2至12的范围内具有高稳定性，同时对蛋白酶K降解敏感，未观察到溶血活性。此外，扫描电子显微镜分析表明，PCM7-4有效地抑制了单核细胞增生李斯特菌细胞的生物膜形成并破坏了细胞膜。转录组分析表明，PCM7-4对与关键代谢途径相关的基因产生影响，包括次级代谢产物的生物合成、磷酸转移酶系统（PTS）以及淀粉/蔗糖代谢。这些发现突出了细菌素PCM7-4在开发针对食源性病原体的有效抗菌干预措施方面的巨大潜力。
