An antifungal protein named PaAFP was isolated and purified from the seeds of Pachyrrhizus erosus by extraction with PB buffer, S Sepharose Fast Flow, CM 52 cellulose and Sephadex G 75 column chromatography. On potato sucrose agar medium, the purified protein obviously inhibited the growth of the important edible fungus pathogens Trichoderma viride and Chrysosporium luteum at 6 2 μg and 12 5 μg per disc respectively. The molecular weight was about 14 kD by SDS PAGE and HPLC. The isoelectric point was pH7 5. Analysis of the composition of amino acids showed that this protein was rich in Asx, but lacking in Met.
From the seeds of red kidney bean( Phaseolus valgaris L.),two novel protein constituents named PV3 and PV5 have been isolated and purified by extraction with PB buffer,S Sepharose Fast Flow column chromatography.These proteins are proved to be homogeneous by SDS PAGE、IEF and HPLC analysis,and presented the typical absorption spectra in ultraviolet region.The molecular weights of the two proteins were approximately 65 kD and 61 kD by HPLC analysis,but 34 kD and 31 kD by using SDS PAGE analysis,respectively.Later two values were in agreement with the amino acid compositions computation.The fact that there were no Cys in these proteins indicated that the subunit was the base composition unit.The isoelectric points of the two proteins were 6.0 and 6.5.The hemagglutinating activity of two proteins was founded.Protein PV3 and PV5 were crystallized using hanging drop vapor diffusion method.
