Purification and characterization of an antimicrobial peptide from Paris polyphylla var.chinensis
华重楼内生菌抗菌肽的分离纯化及其特性

Abstract: Objective] We isolated an endophyte PCE45 from the rhizome of Paris polyphylla var. chinensis. From PCE45, we purified and characterized an antimicrobial peptide. Methods] After ammonium sulfate salting-out, acetone precipitation, SephadexG75,DE52 and SephadexG25 column chromatography, we separated an antimicrobial peptide PCP-1 from the strain PCE45. The stability against high temperature and proteinase, and antimicrobial activity were also analyzed. Results] The antimicrobial peptide PCP-1 was stable to proteinase and tolerated high temperature, strong acid and strong base. PCP-1 caused deformation of the hyphae of Pyricularia oryzae and prohibited the spore germination. It also inhibited fungi such as Curvularia lunata and bacteria such as Escherichia coli. Mass spectrogram measurement revealed its molecular weight of 1058.3 Da. The amino acid composition of the peptide composed of 7 amino acids. Ninhydrin reaction showed negative trait whereas after acid hydrolysis with positive ninhydrin reaction and biuret reaction. Conclusion] The ninhydrin reaction and biuret reaction imply that the peptide PCP-1 is a cyclic lipeptide. This is the first report about antimicrobial peptide from Paris polyphylla var.chinensis.