The unusual metabolism of the cruciferous phytoalexin camalexin by virulent and weakly virulent isolates of the root rot fungus Rhizoctonia solani Kuhn is reported. This biotransformation proceeded via 5-hydroxycamalexin, which was further biotransformed into more polar metabolites. Importantly, the metabolites resulting from transformation of camalexin were significantly less toxic to the pathogen than camalexin. Thus, it was ...
