Isolation and characterization of a novel small antifungal peptide from bacillus megaterium D4 isolated from the dung of wild plateau yak in China

A novel small antifungal peptide-producing strain d4 was isolated from the dung of wild plateau yak and identified as bacillus megaterium. the purification procedure of peptide consisted of acid precipitation,methanol extract and c18 reverse-phase chromatography. the amino acid composition of peptide yp differed from those of antifungal peptides which have been reported to date. peptide yp was proved to be a novel small antifungal cyclic peptide. it exhibited strong inhibitory activity against many phytopathogenic fungi and had a wild range of thermo stability and ph stability and was not susceptible to all proteases tested. © 2010 bentham science publishers ltd.