摘要
目的研究天蚕素A-马盖宁杂合肽对耐甲氧西林金黄色葡萄球菌(MRSA)杀菌作用的作用机制。方法采用微量稀释法测定杂合肽对MRSA的最低抑菌浓度(MIC)。通过透射电子显微镜观察该杂合肽作用于MRSA后细菌细胞膜的变化,采用原子吸收光谱仪检测待测菌液与杂合肽相互作用后细菌细胞外K+的浓度变化,用流式细胞仪分析杂合肽作用于MRSA后细菌细胞膜完整性的变化。结果杂合肽对MRSA的MIC是64μg/mL。通过超微结构图像观察到细菌细胞膜破坏,杂合肽作用后细胞外钾离子浓度的升高,杂合肽引起碘化丙啶(PI)流入细胞质内,PI着染阳性细胞的比率增高。结论天蚕素A-马盖宁杂合肽可能是通过破坏MRSA细胞膜,使细胞外钾离子浓度的升高同时导致PI进入胞质,细胞内部成分被破坏,从而起到杀菌作用。
Objective To study the mechanism of cecropinA-mangainin treatment on the meticillin-resistant Staphylococcus anreus biofilms.Methods The activity of the hybrid antibacterial peptide against Staphylococcus anreus was evaluated by the minimum inhibitory concentration（MIC）test and its effect on the bacteria membrane changes were observed through transmission electron microscope.The concentration of K＋of the tested bacterial liquid after interact with antibacterial peptide was detected with atomic absorption spectrometer.The changes of the treated bacteria biofilm was also evaluated by using flow cytometry.Results The results demonstrated that the MIC of the peptide against Staphylococcus aureus was 64μg/mL.The ultrastructure changes of the meticillinresistant Staphylococcus anreus membrane and the rising concentration of intracellular K＋were observed.And increased number of PI positive cells was also observed after hybrid antibacterial peptide treatmennt.ConclusionThe hybrid antibacterial peptide could kill the meticillin-resistant Staphylococcus anreus by damage the treated bacteria membrane.
出处
《四川大学学报（医学版）》
CAS
CSCD
北大核心
2015年第2期218-221,共4页
Journal of Sichuan University(Medical Sciences)
基金
国家自然科学基金(No.31360622)资助
