School of Biological and Environmental Engineering, Chaohu University, Bantang Road No.1, Chaohu Economic Development Zone, Hefei 238024, China.
Chaohu Regional Collaborative Technology Service Center for Rural Revitalization, Bantang Road No.1, Chaohu Economic Development Zone, Hefei 238024, China.
FEMS Microbiol Lett. 2024 Jan 9;371. doi: 10.1093/femsle/fnae066.
Garviecin LG34 produced by Lactococcus garvieae LG34 exhibits wide-spectrum antibacterial activity against both Gram-positive and Gram-negative bacteria. This work aimed at clarifying the antibacterial mode of action of garviecin LG34 against Gram-negative bacterium Salmonella typhimurium. To determine the concentration for the bacteriocin antimicrobial mode experiments, the minimum inhibitory concentration of garviecin LG34 against S. typhimurium CICC21484 was determined as 0.25 mg/ml. Garviecin LG34 decreased the viable count of S. typhimurium CICC21484 and its antibacterial activity was the dose and time dependant. Garviecin LG34 led to the dissipation of transmembrane potential, the rise in the extracellular conductivity, UV-absorbing material at 260 nm, and LDH level of S. typhimurium CICC21484. Scanning electron micrographs results shown that garviecin LG34 cause dramatic deformation and fragmentation including the flagellum shedding, pores formation in surface, and even completely breakage of S. typhimurium cell. Moreover, garviecin LG34 decreased the intracellular ATP level. The results of this study demonstrated that garviecin LG34 can destroy cell structure, increase membrane permeability of S. typhimurium, thereby might be used as biopreservative for treating food borne and salmonellosis resulting from Gram-negative bacterium S. typhimurium.
由乳球菌 LG34 产生的加味素 LG34 对革兰氏阳性和革兰氏阴性细菌均表现出广谱抗菌活性。本工作旨在阐明加味素 LG34 对革兰氏阴性菌鼠伤寒沙门氏菌的抗菌作用模式。为了确定抗菌模式实验的抑菌浓度，测定了加味素 LG34 对鼠伤寒沙门氏菌 CICC21484 的最小抑菌浓度为 0.25 mg/ml。加味素 LG34 降低了鼠伤寒沙门氏菌 CICC21484 的活菌计数，其抗菌活性与剂量和时间有关。加味素 LG34 导致跨膜电位耗散、细胞外电导率升高、260nm 处紫外吸收物质和鼠伤寒沙门氏菌 CICC21484 的 LDH 水平升高。扫描电子显微镜结果表明，加味素 LG34 导致鼠伤寒沙门氏菌细胞严重变形和破裂，包括鞭毛脱落、表面形成孔，甚至完全断裂。此外，加味素 LG34 降低了细胞内 ATP 水平。本研究结果表明，加味素 LG34 可以破坏细胞结构，增加鼠伤寒沙门氏菌的膜通透性，因此可能被用作生物防腐剂来治疗食源性和由革兰氏阴性菌鼠伤寒沙门氏菌引起的沙门氏菌病。
