Zn2+, a key factor of colony morphogenesis of Tricholoma matsutake

Abstract

Tricholoma matsutake is a basidiomycete producing edible fruiting bodies known as matsutake in Japanese. Matsutake is one of the most valuable edible mushrooms in Japan. Colony morphology on agar plates of T. matsutake is known to vary depending on compositions of media used, while the mechanism is still unknown. In our present work, we have found Zn2+ affects colony morphology of T. matsutake. When Zn2+ was added at concentration more than 1 µM, colony got wrinkled and aerial hyphae formation was activated. No such morphological changes have been confirmed without Zn2+ addition or at concentration less than 1 µM, even when other nutritional ingredients are provided sufficiently. None of the Zn2+ concentrations examined present has affected colony diameter, dry weight, and water content. These findings imply Zn2+ is a key factor involved in colony morphogenesis of T. matsutake such as colony wrinkling and aerial hyphae formation. Metabolomic information obtained with gas chromatography–mass spectrometry has indicated that Zn2+ deficiency has influences on carbohydrate and l-serine metabolisms.