In order to reveal the regulation of the glucoamylase gene from Pholiota microspora, the promoter region about 2734 bp upstream of the start codon of PnGlu1 gene was amplified and characterized. Two TATA box like sequences and consensus sequences of two yeast mating factor alpha1 (MATα1) and three mating factor a1 (MATa1) binding sites were discovered. To investigate the relationship between regulation of PnGlu1 and the mating type system, PnGlu1 gene expression was investigated in a monokaryon, a dikaryon and four transformants into which were introduced homeodomain protein genes. PnGlu1 gene expression was induced in the dikaryon, and PnGlu1 gene expression in four transformants was higher than that in the monokaryon. To investigate the relationship between regulation of PnGlu1 and fruiting body development, P. microspora was cultivated in sawdust media and then quantitative reverse transcription-PCR was carried out. The PnGlu1 expression level, glucoamylase activity and glucose content dramatically increased until fruiting. These results suggested that glucoamylase gene expression is closely related with dikaryotization and fruiting body development.

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The enzyme in Pleurotus cornucopiae var. citrinopileatus which produces yellow pigment from L-DOPA was isolated from the fruit body and characterized. The enzyme was purified from fruit body homogenate to electrophoretic homogeneity by ammonium sulfate precipitation, anion exchange chromatography and gel-filtration. The molecular weight of the purified enzyme was estimated to be 19 kDa by SDS-PAGE and 350 kDa by HPLC-GPC. The purified enzyme was stable between pH 5 to 8 and at temperatures up to 28℃; maximum activity was observed at 28℃ and pH 8. Enzyme activity was considerably inhibited by Co^<2+>, Fe^<2+>, Hg^+, Pb^<2+>, and metal ion chelator EDTA. The enzyme can use L-DOPA and dopamine as substrates with Km values of 1.2 and 1.1 mM, respectively. However, the enzyme could not utilize tyrosine and catechol, which are usual tyrosinase substrates.

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The pink and yellow pigments of Pleurotus salmoneostramineus L. Vass. were separated by gel filtration. The pink pigment was purified as a chromoprotein by purification procedures that included successive ammonium sulfate fractionation and DEAE-Toyopearl and Toyopearl HW55 column chromatography. A single protein band was observed following SDS-PAGE, and its molecular mass was estimated to be approximately 24.5 kDa. The relative molecular mass of the native chromoprotein, as estimated based on its behavior in high-performance liquid chromatography-gel permeation chromatography (HPLC-GPC), was approximately 30 kDa. The chromoprotein was stable against heating at 28℃ for 30 min and at pH values between 4 and 10. The major absorption maxima of the chromoprotein were observed at 267, 348, and 493 nm. The three yellow pigments were purified by repeated gel filtration on Sephadex G-25 columns. The molecular masses of the yellow pigments were estimated by HPLC-GPC as 10.8, 5.3 and 4.4 kDa. None of the isolated yellow pigments showed specific maximum absorption in the visible region, and all of the yellow pigments were soluble only in water. The pigments were bleached by H_2O_2, KMnO_4, and NaOCl, and reduced Fe^<3+> to Fe^<2+>. These characteristics are consistent with those of melanin pigments.

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