多肽APS体外抗病原真菌活性及其抗菌机理初探

Inhibition Property of a Polypeptide APS Against Phytopathogenic Fungi and the Possible Antifungal Mechanism

目的 探讨抗菌肽 APS的体外抗病原真菌的活性及可能的抗菌机理。方法 微量稀释法测定 APS对不同真菌的最低抑菌浓度 (MIC)及最低杀菌浓度 (MBC) ,并检测 APS对脂质平面膜电学性质的影响。结果 除过烟曲霉菌外 ,APS对其它受试病原真菌有较低的 MIC及 MBC。同时 ,经 APS作用后 ,脂质平面膜上形成跨膜电流。结论 APS对多种常见病原真菌均有较强的抑制和杀灭作用。APS抗真菌的可能机制是在膜上持续形成孔道(pores) ,破坏了膜的完整性 ,引起细胞内容物的外流 。

Objective To investigate the inhibition property of a novel antifungal polypeptide APS in vitro and its possible antifungal mechanism. Methods The minimal inhibitory concentration(MIC) and minimal bactericidal concentration(MBC) of APS against different fungi were detected by microdilution test. And the voltaic change of planar lipid bilayer was observed during APS treatment. Results APS at low MIC and MBC was shown to have effects on phytopathogenic fungi tested except aspergillus fumigatus, the minimum values of MIC and MBC being 1.43 μg/ml and 1.78 μg/ml respectively. After APS was put in, the transmembrane current could be recorded. Conclusion APS has strong inhibitory effects on the germination of spores of several phytopathogenic fungi. Its antifungal mechanism is likely to form persistent pores on the cell membrane, thus causing membrane permeation and the death of fungi.