Isolation and characterization of Schizophyllum commune mutants resistant to indole and caffeine

Two compound-resistant mutants of Schizophyllum commune, In-R-13 (indole resistance) and Caf(R)-9 (caffeine resistance), were screened. The In-R-13 and Caf(R)-9 mutants were characterized by unrepressed and depressed mycelial growth on plates containing indole (350 mu g/ml) and caffeine (4 mg/ml) respectively, and both of them showed flat morphology on an unselective medium. Sexually compatible mating between the mutants and wild-type compound-sensitive strains showed dominant character of specific compound resistance with fruiting in the presence of indole (60 mu g/ml), and the fruit body formation of resulting crosses was advanced by the addition of either diphenylamine or benzoic acid. The partial dikaryons (semicompatible), In-R-13xT37 and Caf(R)-9xT37, showed a B-common phenotype (A not equal B=) with pseudoclamp and nonfruiting. This indicates that the mutations responsible for indole and caffeine resistance may affect the function of B-factor.