Heat Induced Conformational Changes Generate Mitogenicity to Splenocytes by Sclerogen from Sclerotinia sclerotiorum IFO 9395

The fungal mitogen, sclerogen, obtained from sclerotia of Sclerotinia scleotiorum IFO 9395 showed significant mitogenic activity to murine splenocytes after heat denaturation in relation to polymerization. To evaluate the conditions generating mitogenicity, we performed several chromatographic and spectral analyses. After heat denaturation of sclerogen, significant reduction of intrinsic fluorescence, sigificant changes on the ultraviolet absorption spectrum, sigificant changes on the circular dichroism specturm, and an extreme change of the surface charge to anionic, were observed. These results strongly suggested that local as well as overall conformational changes of sclerogen associated with a high molecular mass and polyanionic chargres are important in generating mitogenicity to murine splenocytes.