INFECTIVITY SUPPRESSING AND VIRUS-BINDING ACTIVITIES OF A MEMBRANE MATERIAL ISOLATED FROM TOBACCO-LEAVES

TMV binding substance (R) was isolated from a tobacco leaf membrane fraction and was purified by extraction with organic solvents and by column chromatography. Experimental results suggest that the binding of R with TMV results in inactivation of TMV. When tobacco leaves were inoculated with the R‐TMV complex, it was found that the formation of polysome containing infecting viral RNA was inhibited. Model experiments showed that the mode of R‐TMV adsorption to the membrane is different from that of TMV adsorption and that stripping of coat protein from TMV by SDS was inhibited by R. A possible explanation for the mechanism of this inhibition by R is that the R‐TMV complex follows a pathway which does not lead to establishment of infection. Although less efficient, R was still active when it was applied after virus inoculation. Due to its affinity to coat protein, R might also interfere with a later process of viral multiplication. © owned by Center for Academic Publications Japan (Publisher)