We studied on two DNA-binding proteins PRIB and Le. CDC5 of Lentinula edodes. PRIB possessed a DNA-binding domain consisting of Zn(II)2Cys6 and bZIP motifs and bound to a 16-bp sequence with the consensus sequence 5'-GGGGGGGACAGGANCC-3'. Three target genes of PRIB were identified: priB, uck1 (UMP-CMP kinase gene) and a novel gene (named mfbC). The uck1 gene appeared to play a role in nucleotide biosynthesis especially for production of basidiospores and divergence of mycelial cells in the hymenophore. MFBC, the product of mfbC gene, interacted with eIFSA and may play a role in the divergence of mycelial cells. Le. CDC5 contained a c-Myb-type DNA-binding domain and a leucine zipper and bound to a 7-bp sequence with the consensus sequence 5'-GCAATGT-3'. Le. CDC5 and the novel interacting protein CIPB, which bound to a 6-bp sequence with the consensus sequence 5'-CAACAC/T/G-3', appeared to regulate the transcription of the ctg1 gene involved in regulation of stipe elongation. We also identified blue-light photoreceptor PHRA and its interacting protein PHRB, which are most likely involved in fruiting initiation and development of L. edodes. Although PHRA seemed to bind to DNA non-specifically, PHRB bound to a 7-bp sequence with consensus sequence 5'-GATA/TTT/G/AC-3' and the consensus sequence in the 5'-upstream promoter region of L. edodes tyrosinase gene (Le. tyr). We succeeded in breeding Coprinopsis cinerea monokaryotic strains with high lignin- and xylan-degrading activities and Trametes hirsuta monokaryotic strains producing large amounts of lignin-degrading enzymes or rat cytochrome P450, CYP1A1. C. cinerea strains were used to isolate cellulose from rice straw and T. hirsuta strains were used to degrade dioxins.

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We previously discovered that some genera of mushroom including Schizophyllum produce alcohol dehydrogenase (ADH), allowing wine production via mushrooms instead of Saccharomyces cerevisiae. In this study, we examined the 40-kDa ADH monomer in S. commune for wine production. The alcohol production of S. commune was better under aerobic than anaerobic conditions. Grape juice with 25% sugar concentration was suitable for wine production (6.6% alcohol) using S. commune. Arg, Ala, Glu and Ser were formed in blueberry wine through mushroom fermentation of its juice. The ratio of sweet amino acids like Ala to total amino acids in blueberry wine was higher than that in grape wine. Grape wine produced under aerobic conditions showed fibrinolytic activity on a fibrin plate. Thrombin clotting of blueberry wine produced by S. commune under aerobic conditions was more than 20 times longer than that of the control (blueberry juice). Thus, wine made with S. commune seems to be a functional food with potential preventive effects against thrombosis.

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Application of spent substrate of shiitake (Lentinula edodes) for compost was investigated. The severity of anthracnose symptoms was extremely low in cucumber plants grown in the nursery soil containing spent substrate. Anthracnose symptoms were even inhibited by autoclaved spent substrate. Expression of the POD gene, a putative systemic acquired resistance marker in cucumber, was higher in plants grown in nursery soil containing spent substrate than in control plants. These results indicate that spent shiitake substrate may be a valuable addition to nursery soil for cucumber plant production.

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In order to investigate the efficient use of food waste (sesame hulls) and determine the changes in the form of calcium contained therein, a strain of Pleurotus ostreatus was cultured on media enriched with sesame hulls, and mycelial growth rate, fruiting body yield, calcium content and calcium form were determined. The mycelial growth rate for sawdust and sesame hull (weight ratio of 7:3 and 8:2) medium was comparable to that for sawdust to rice bran (volume ratio of 5:1) medium; thus, sesame hulls can be used as a medium substrate. The calcium content of fruiting bodies cultivated on rice bran media was higher than those on mixed media containing sesame hulls. Among the fruiting bodies cultivated on mixed media containing sesame hulls, the calcium content of fruiting bodies was highest for the 9:1 sawdust to sesame hull medium. The fruiting body yield for 100% sesame hull medium was the highest, and about 72% of the calcium in those fruiting bodies was water-soluble. By cultivating P. ostreatus on 100% sesame hull medium, calcium oxalate in sesame hulls is converted inside the fruiting bodies into calcium salts that are slightly more absorbable by the human body.

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