Fungal enzymatic activity in fruitbodies

This study describes a novel method for a culture-independent assay to test enzymatic activity of different fungal strains, using fresh fruitbody expl ants taken from metabolically active areas of fungi. Hydrolases (chitinases , exoglucanases) activity was measured using methylumbelliferyl-labeled sub strate analogs; for oxidases (phenoloxidases, peroxidases) activity natural substrates such as guaiac gum or pyrogallol/H2O2 were used. To exclude pot ential enzymatic activity of bacteria attached to fruitbodies antibiotics w ere applied. The results suggest that most ectomycorrhizal fungi tested wer e able to form peroxidases. Some genera could also produce phenoloxidases, e.g. almost all strains of Lactarius, Russula, and Laccaria; other genera d id not exude phenoloxidases into the test medium. This was the case for alm ost all strains of Boletaceae. Other genera did not show any genus specific enzyme activity pattern, e.g. Cortinarius and Tricholoma. Whether these en zymatic activities tested on fruitbodies of ectomycorrhizal fungi occur als o in the soil and whether they have an ecological impact on fungal growth a nd tree nutrition has still to be studied.