| Many kinds of protein were obtained by ion-exchange chromatography and Gel filtration from the dry sample of the edible mushroom, Pleurotus eryngii. In terms of local lesion on hosts, these components were confirmed to be against Tobacco mosaic virus ( TMV) and their inhibition rates reach more than 70%, or even 99%. The protein named xb68Ab of MW 23.7kDa was purified by ion-exchange chromatography and Gel filtration. Its inhibition rates against TMV are 99. 43% and 98.9% on Nicotians glutionosa and Chenopodium amaranticolor, respectively.An antiviral protein, YP46-46, was isolated and purified to homogeneity from the edible mushroom, Plearotus citrinopileatus,by precipitation of 40%-60% saturation of ammonium sulfate, followed by DEAE-sepharoseFF ion-exchange column chromatography, and SephacrylS-200 High Resolution molecular sieve chromatography. The protein has a molecular weight of about 27.4kDa by SDS-PAGE. The concentration of the protein is 0.24 M g/mL when the inhibition rate against TMV is 50%. According to the assay system based on HepG2.2. 2.15 cell line, YP46-46 was studied on its inhibitory ability against Hepatitis B virus(HBV). The result shows that the concentration of YP46-46 at inhibition rate of 50% against HBsAg is 0.08u g/mL , but YP46-46 has low effect on HBeAg.Another antiviral protein ,Zb, was also purified to homogeneity from the edible mushroom, Flammulina velutipes, by DEAE-sepharosePF ion-exchange column chromatography ,Superdex75 Gel filtration chromatography and high performance liquid chromatography. The study shows that its content is different in different seasons in the basidiocarps ofthe edible mushroom Flammulina velutipes. In terms of observation of local lesion on Nicotiana glutinosa by half leaf method, the protein has a 50% inhibition rate against TMV when its concentration is 4. 4n g/mL. By observation of TMV treated by Zb throughout the electron microscope via negative-stain and colloidal gold-stain , Zb can result in the degradation of the virions of TMV. It is presumed that Zb act on the capsid of TMV, but not RNA of TMV. By assaying the activity of HBV inhibition in vitro on HepG2. 2.2. 15 cell line, the result shows that the concentrationof Zb is 0.117mg/mL when it has a inhibition rate of 50% against HBsAg , but Zb has low effect on HBeAg as well as YP46-46.It is also found that. Zb has a hemagglutination activity and its titer of agglutinating erythrocytes is 2"12 on the human erythrocytes of type A, B, 0 and the rabbit erythrocytes when the start concentration of Zb is 0. 2961mg/mL. The activity of Zb inhibiting tumor was assayed, and the concentration of Zb is 0. 75ug/mL when carcinoma MGC80-3 cell of 50% is inhibited .Carcinoma MGC80-3 cell can be observated to be lysed by Zb throughout microscope. Zb shows no inhibiting effect on Botrytis clnerea, Fusarium oxysporum, Colletotrichum piperatum, Pseudomonas solanaceavum, Xanthomonas oryzae (Vyedaet Ishiyama) Dowson by means of spore germination method.The antiviral protein, Zb, has an apparent molecular mass of about 30 kDa by SDS-polyacrylamide gel electrophoresis(SDS-PAGE) with or without prior boiling or denaturalization, which indicates that Zb has only a subunit. It has an isoelectric point of 4. 7. Sugar analysis indicates the absence of carbohydrate for Zb. Its N-end sequence of 20 amino acid residues was obtained by amino acid sequencing and it can be confirmed that Zb is the protein TDP or flammutoxin reported by Watanabe et al (1999) and Tomitaetal(1998) . The peptide-mass fingerprinting of Zb degraded by trypsin was obtained via mass spectrometry. The antiserum of Zb was obtained after the protein Zb purified by SDS-PAGE immunnised rabbit of about 3kg , and its high titer and speciality was detected by enzyme-linked immunosorbent assay and western immunoblot.According to the TDP gene sequence, cDNA of Zb was obtained by reverse transcription-polymerase chain reaction. By sequencing cDNA of Zb, its open reading frame encode 272 amino acid residues, which contain a cysteine residue and i...
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