Transcriptional analysis of genes encoding ß-glucosidase of Schizophyllum commune KUC9397 under optimal conditions.

The present study was conducted to determine the gene responsible for beta-glucosidase (BGL) production and to generate a full-length complementary DNA (cDNA) of one of the putative BGL genes, which showed a significant expression level when Schizophyllum commune KUC9397 was grown in optimized medium. The relative expression levels of seven genes encoding BGL of S. commune KUC9397 were determined with real-time quantitative reverse transcription PCR in cellulose-containing optimized medium (OM) compared to glucose-containing basal medium (BM). The most abundant transcript was bgl3a in OM. The transcript number of the bgl3a increased more than 57.60-fold when S. commune KUC9397 was grown on cellulose-containing OM compared to that on glucose-containing BM. The bgl3a was identified, and a deduced amino acid sequence of bgl3a shared homology (97%) with GH3 BGL of S. commune H4-8. This is the first report showing the transcription levels of genes encoding BGL and identification of full-length cDNA of glycoside hydrolase 3 (GH3) BGL from S. commune. Furthermore, this study is one of the steps for consolidated bioprocessing of lignocellulosic biomass to bioethanol.

Enhanced removal of PAHs by Peniophora incarnata and ascertainment of its novel ligninolytic enzyme genes.

The hazardous effects of the PAHs should be managed by removal using white rot fungal ligninolytic enzymes. The white rot fungus Peniophora incarnataKUC8836 was stimulated to produce ligninolytic enzymes in a liquid medium by the addition of four substances: 0.5 g L(-1) Tween 80, 70 mg L(-1) CuSO4·5H2O, 10 mg L(-1) MnSO4·H2O, and 0.3 g L(-1) veratryl alcohol. The experiments were carried out in two different media: basal salt and 2% malt extract (ME) liquid medium. Under the experimental conditions, both laccase and manganese-dependent peroxidase (MnP) demonstrated with the highest activities in 2% ME liquid medium following the addition of Tween 80. The biodegradation of anthracene and pyrene was significantly enhanced by the induced ligninolytic enzymes when Tween 80 was added. Tween 80 is a viable co-substrate for P. incarnata, as it enhances the ability of P. incarnata to manage effective biodegradation of PAHs. Most of all, the novel laccase and MnP genes ascertained in this study, showed that the genes were involved in the production of ligninolytic enzymes from P. incarnataKUC8836.

Investigation of Marine-Derived Fungal Diversity and Their Exploitable Biological Activities.

Marine fungi are potential producers of bioactive compounds that may have pharmacological and medicinal applications. Fungi were cultured from marine brown algae and identified using multiple target genes to confirm phylogenetic placement. These target genes included the internal transcribed spacer (ITS), the nuclear large subunit (LSU), and the ß-tubulin region. Various biological activities of marine-derived fungi were evaluated, including their antifungal, antioxidant and cellulolytic enzyme activities. As a result, a total of 50 fungi was isolated from the brown algae Sargassum sp. Among the 50 isolated fungi, Corollospora angusta was the dominant species in this study. The genus Arthrinium showed a relatively strong antifungal activity to all of the target plant pathogenic fungi. In particular, Arthrinium saccharicola KUC21221 showed high radical scavenging activity and the highest activities in terms of filter paper units (0.39 U/mL), endoglucanase activity (0.38 U/mL), and ß-glucosidase activity (1.04 U/mL).

Comparison of the Diversity of Basidiomycetes from Dead Wood of the Manchurian fir (Abies holophylla) as Evaluated by Fruiting Body Collection, Mycelial Isolation, and 454 Sequencing.

In this study, three different methods (fruiting body collection, mycelial isolation, and 454 sequencing) were implemented to determine the diversity of wood-inhabiting basidiomycetes from dead Manchurian fir (Abies holophylla). The three methods recovered similar species richness (26 species from fruiting bodies, 32 species from mycelia, and 32 species from 454 sequencing), but Fisher's alpha, Shannon-Wiener, Simpson's diversity indices of fungal communities indicated fruiting body collection and mycelial isolation displayed higher diversity compared with 454 sequencing. In total, 75 wood-inhabiting basidiomycetes were detected. The most frequently observed species were Heterobasidion orientale (fruiting body collection), Bjerkandera adusta (mycelial isolation), and Trichaptum fusco-violaceum (454 sequencing). Only two species, Hymenochaete yasudae and Hypochnicium karstenii, were detected by all three methods. This result indicated that Manchurian fir harbors a diverse basidiomycetous fungal community and for complete estimation of fungal diversity, multiple methods should be used. Further studies are required to understand their ecology in the context of forest ecosystems.

Wood decay fungi in South Korea: polypores from seoul.

In Seoul, a majority of plant communities have undergone significant changes over the last few decades; however, how wood decay fungi have responded and adapted to the changes in vegetation remains unknown. Through an ongoing investigation of Korean indigenous fungi, ca. 300 specimens with poroid basidiocarp were collected in Seoul during 2008~2012. Morphological examination and molecular analysis using the internal transcribed spacer and nuclear large subunit ribosomal DNA region sequences helped identify 38 species belonging to 28 genera, 10 families, and 5 orders in this area. Among them, three polypores, Abundisporus pubertatis, Coriolopsis strumosa, and Perenniporia maackiae were found to be new to South Korea.

Isolation and analysis of the enzymatic properties of thermophilic fungi from compost.

To the best of our knowledge, this is the first report on thermophilic fungi isolated in Korea. Three species of thermophiles were isolated from compost and were identified as Myriococcum thermophilum, Thermoascus aurantiacus, and Thermomyces lanuginosus. They can grow at temperatures above 50℃ and produce high levels of cellulolytic and xylanolytic enzymes at high temperatures. Notably, the considerable thermostability of the endo-glucanase produced by T. aurantiacus has made the fungus an attractive source of industrial enzymes.

Biotechnological procedures to select white rot fungi for the degradation of PAHs.

White rot fungi are essential in forest ecology and are deeply involved in wood decomposition and the biodegradation of various xenobiotics. The fungal ligninolytic enzymes involved in these processes have recently become the focus of much attention for their possible biotechnological applications. Successful bioremediation requires the selection of species with desirable characteristics. In this study, 150 taxonomically and physiologically diverse white rot fungi, including 55 species, were investigated for their performance in a variety of biotechnological procedures, such as dye decolorization, gallic acid reaction, ligninolytic enzymes, and tolerance to four PAHs, phenanthrene, anthracene, fluoranthene, and pyrene. Among these fungi, six isolates showed the highest (>90%) tolerance to both individual PAH and mixed PAHs. And six isolates oxidized gallic acid with dark brown color and they rapidly decolorized RBBR within ten days. These fungi revealed various profiles when evaluated for their biotechnological performance to compare the capability of degradation of PAHs between two groups selected. As the results demonstrated the six best species selected from gallic acid more greatly degraded four PAHs than the other isolates selected via tolerance test. It provided that gallic acid reaction test can be performed to rank the fungi by their ability to degrade the PAHs. Most of all, Peniophora incarnata KUC8836 and Phlebia brevispora KUC9033 significantly degraded the four PAHs and can be considered prime candidates for the degradation of xenobiotic compounds in environmental settings.

White-rot fungus Merulius tremellosus KUC9161 identified as an effective degrader of polycyclic aromatic hydrocarbons.

Polycyclic aromatic hydrocarbons (PAHs) have a highly recalcitrant structure; however, they can be degraded by white-rot fungi which have the potential to biodegrade recalcitrant organic compounds. Four fungal isolates were selected from 23 newly isolated basidiomycetes, based on their dye decolorization rate, and they were evaluated for their ability to degrade 50 ppm of pyrene. The isolate phylogenetically affiliated to Merulius tremellosus KUC9161 demonstrated the highest degradation rate of pyrene, regardless of the production of ligninolytic enzyme activities. The selected isolates were tested for their ability to degrade pyrene and other PAHs in creosote-contaminated soil. The results of the degradation tests indicated that M. tremellosus KUC9161 degraded a larger variety of PAH compounds than Phanerochaete chrysosporium, a known PAH degrader. On the basis of our results, the isolate M. tremellosus KUC9161 has a high potential to be used in the large-scale biodegradation of PAHs, and the species may also be used to degrade recalcitrant materials in creosote-contaminated soil.

Diversity of fungi in creosote-treated crosstie wastes and their resistance to polycyclic aromatic hydrocarbons.

This study was conducted to generate information regarding the diversity of fungi inhabiting creosote-treated wood in a storage yard for crosstie wastes in Gwangmyeong, Korea. Additionally, the resistance to polycyclic aromatic hydrocarbons (PAHs) of indigenous fungi that mainly occupy creosote-treated wood was evaluated. We isolated fungi from the surface and inner area of crosstie wastes and identified them using a combination of traditional methods and molecular techniques. Overall, 179 isolates including 47 different species were isolated from 240 sampling sites. The identified fungal species included 23 ascomycetes, 19 basidiomycetes, and 5 zygomycetes. Three species, Alternaria alternata, Irpex lacteus, and Rhizomucor variabilis, were the most frequently isolated ascomycetes, basidiomycetes, and zygomycetes, respectively. The results of this study showed that there was a large difference in the fungal diversity between the surface and the inner area. Additionally, zygomycetes and ascomycetes were found to have a greater tolerance to PAHs than basidiomycetes. However, two basidiomycetes, Heterobasidion annosum and Schizophyllum commune, showed very high resistance to PAHs, even in response to the highest concentration (1,000 ppm), which indicates that these species may play a role in the degradation of PAHs.