PDF(Pubmed)
Abstract：
The present study aimed to characterize the mode of action of a novel antimicrobial peptide isolated from egg yolk hydrolysate. The EYHp6, KGGDLGLFEPTL, exhibited inhibition against Salmonella enterica serovar Typhimurium TISTR 292 and S. enterica serovar Enteritidis DMST 15679 with a MIC value of 2 mM. In contrast, S. enterica serovar Newport ATCC 6962 and other strains of Typhimurium and Enteritidis were inhibited at 4 mM. EYHp6 increased the cell membrane permeability of S. Typhimurium TISTR 292, leading to DNA leakage. Membrane integrity determined by propidium iodide and SYTO9 staining visualized by confocal microscopy demonstrated that EYHp6 at 1 × MIC induced disruption of cell membranes. Electron microscopy revealed that treatment of S. Typhimurium with EYHp6 led to damage to the cell membrane, causing the leakage of intracellular contents. Synchrotron-based Fourier-transform infrared spectroscopy indicated that EYHp6 killed S. Typhimurium by targeting fatty acids and nucleic acids in the cell membrane. The peptide did not show hemolytic activity up to 4 mM. These findings suggest that EYHp6 could be a promising antibacterial agent for controlling the growth of S. enterica.
摘要：
本研究旨在表征从蛋黄水解物中分离的新型抗菌肽的作用方式。EYHp6，KGGDLGLFEPTL，表现出对肠道沙门氏菌TISTR292和肠道沙门氏菌DST15679的抑制作用，MIC值为2mM。相比之下,大肠杆菌血清变型NewportATCC6962和其他鼠伤寒和肠炎菌株在4mM时被抑制。EYHp6增加了鼠伤寒沙门氏菌TISTR292的细胞膜通透性，导致DNA泄漏。通过碘化丙啶测定的膜完整性和通过共聚焦显微镜观察的SYTO9染色表明，1×MIC的EYHp6诱导细胞膜破坏。电子显微镜显示，用EYHp6处理鼠伤寒沙门氏菌导致细胞膜损伤，导致细胞内内容物的泄漏。基于同步加速器的傅里叶变换红外光谱表明，EYHp6通过靶向细胞膜中的脂肪酸和核酸杀死了鼠伤寒沙门氏菌。该肽在高达4mM时不显示溶血活性。这些发现表明EYHp6可能是控制肠链球菌生长的有前途的抗菌剂。
