COMPARATIVE-ANALYSIS OF THE IN-VIVO AND IN-VITRO METABOLITES PRODUCEDBY THE ENTOMOPATHOGEN BEAUVERIA-BASSIANA

Beauveria bassiana, like other insect mycopathogens, has evolved mecha nisms to penetrate the insect exoskeleton via germ tubes and to replic ate in the host hemocoel. Our initial studies have shown that biologic ally active metabolites released in the hemolymph during the vegetativ e growth phase of B. bassiana disrupt the host immune response and met amorphosis. These components cause an immediate reduction in filopodia l-producing hemocytes and an increase in the level of serum phenoloxid ase. Radiolabeling of tissues explanted from healthy versus infected l arvae has demonstrated both the induction and repression of polypeptid es in B. bassiana infected hemolymph. None of the polypeptides detecte d with S-35 pulse labeling were responsible for the cytotoxic and inse cticidal activities detected in infected hemolymph. Western blots of S DS gels containing chromatographic fractions from healthy and infected sera probed with both antibodies against B. bassiana cell homogenates and culture filtrates contained a complex of antigens. The results of lectin labeling and sodium periodate treatments suggested that carboh ydrates were the major epitopes being recognized by both monoclonal an d polyclonal probes.