[Inhibition property of a polypeptide APS against phytopathogenic fungi and the possible antifungal mechanism].

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 micrograms/ml and 1.78 micrograms/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.