Zhang Xu, Wang Yang, Liu Lei, Wei Yunlu, Shang Nan, Zhang Xiangmei, Li Pinglan
Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science & Nutritional Engineering, China Agricultural University, Beijing 100083, China.
Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Food Science & Nutritional Engineering, China Agricultural University, Beijing 100083, China.
Biochim Biophys Acta. 2016 Feb;1858(2):274-80. doi: 10.1016/j.bbamem.2015.11.018. Epub 2015 Nov 23.
Biologically active, artificially synthesized two-peptide bacteriocin PlnEF was used to study its mode of action on sensitive bacteria Lactobacillus plantarum pl2. The data obtained showed that PlnEF induced membrane permeabilization, allowing for the efflux of electrolytes, which was evidenced by the increased extracellular conductivity, the dissipation of transmembrane electrical potential and pH gradient, and rapid intracellular ATP depletion after L. plantarum pl2 cells were treated with PlnEF for minutes. Laser confocal microscopy showed that PlnEF accumulated very quickly in L. plantarum pl2 cells and the accumulation of PlnEF caused damage to cell membrane. Scanning electron microscopy and transmission electron microscopy further showed that PlnEF induced morphological changes and structure disruption to L. plantarum pl2 cells, such as the formation of blebs, microspheres, membrane deformation and cell lysis. In summary, the data obtained show that PlnEF caused cell membrane damage to L. plantarum pl2 cells. Our study reveals the antimicrobial mechanism of two-peptide bacteriocin PlnEF against L. plantarum.
具有生物活性的人工合成二肽细菌素PlnEF被用于研究其对敏感菌植物乳杆菌pl2的作用模式。所获得的数据表明，PlnEF诱导细胞膜通透性增加，导致电解质外流，这可通过细胞外电导率增加、跨膜电位和pH梯度的消散以及植物乳杆菌pl2细胞经PlnEF处理数分钟后细胞内ATP迅速耗竭得以证明。激光共聚焦显微镜显示，PlnEF在植物乳杆菌pl2细胞中积累非常迅速，且PlnEF的积累对细胞膜造成损伤。扫描电子显微镜和透射电子显微镜进一步显示，PlnEF诱导植物乳杆菌pl2细胞发生形态变化和结构破坏，如形成泡状、微球体、膜变形和细胞裂解。总之，所获得的数据表明，PlnEF对植物乳杆菌pl2细胞造成了细胞膜损伤。我们的研究揭示了二肽细菌素PlnEF对植物乳杆菌的抗菌机制。
