Characterization of the glutathione S-transferases that belong to the GSTFuA class in Ceriporiopsis subvermispora: Implications in intracellular detoxification and metabolism of wood-derived compounds.

Glutathione S-transferases (GSTs) of wood-degrading fungi play essential roles in cellular detoxification processes and endogenous metabolism. Fungal GSTs of GSTFuA class are suggested to be involved in lignin degradation. Ceriporiopsis subvermispora is one of the important model fungi of the selective lignin degraders, we found it interesting to study its GSTs. Here, we characterized the activities of two GSTs of the GSTFuA class of C. subvermispora (CsGST63524 and CsGST83044). A high-yield expression systems involving Escherichia coli was developed for each of these enzymes. Both enzymes were found to exhibit GSH-conjugation activity toward 1-chloro-2,4-dinitrobenzene, and GSH-peroxidase activity toward cumene hydroperoxide. Both enzymes showed high GSH-conjugation activity under basic conditions (pH8.0 to 9.0), and the optimum temperature for their activity was 40°C. In addition, three fluorescent compounds were used i.e., methylumbelliferyl acetovanillone was used to monitor etherase activity, and 5-chloromethylfluorescein diacetate and 4-methylumbelliferyl acetate to monitor esterase activity. CsGST83044 exhibited both etherase and esterase activities, while CsGST63524 displayed only esterase activity, which was much higher than that of CsGST83044. These findings imply the functional diversity of the GSTFuA class GSTs of C. subvermispora, suggesting that each protein plays distinctive roles in both the fungal detoxification system and wood compound metabolism.

Two new polyols from cultures of the fungus Daedaleopsis tricolor.

Two new polyols, (2E,4E)-octa-2,4-diene-1,6,7-triol (1) and (E)-7,8-dihydroxyoct-5-en-2-one (2) were isolated from cultures of the basidiomycete Daedaleopsis tricolor. Their structures were elucidated by spectroscopic methods including extensive 2D NMR techniques. Two compounds showed no significant activity against five human cancer cell lines.

Biological characteristics of teleomorph and optimized in vitro fruiting conditions of the Hoelen medicinal mushroom, Wolfiporia extensa (Higher Basidiomycetes).

Wolfiporia extensa is a basidiomycetous brown rot fungus and is of well-known medicinal import in China, Japan, and other Asiatic countries. Fruiting body induction is of major relevance for basic biological research and for their use in industrial applications. Based on the evaluation of the effects of temperature, time in the dark before induction and culture, and wounding treatment on fruiting, this report describes the most efficient protocol for inducing fruiting of W. extensa growing on agar plates. Furthermore, several biological characteristics of teleomorph, such as the locations of hymenium, the configuration of basidiospores and primary mycelia, and events involved in basidiosporogenesis in W. extensa, were analyzed for the first time using fluorescence microscopy. The results showed that the hymenium born on both sides of the wall of the honeycomb-like structure on the surface of fruiting bodies and the hymenophoral trama situated in the middle. Each basidia has 4 binuclear basidiospores, and the primary mycelia are multinucleate without clamp connections. These results broaden our knowledge about this brown rot fungus and promote further studies of the sexual reproduction, fruiting body development, and advancement of breeding program, new topics related to the contents of pharmacologically active substances in W. extensa fruiting bodies.

Morphological and molecular evidence for two new species of Laetiporus (Basidiomycota, Polyporales) from southwestern China.

Two Laetiporus species, L. ailaoshanensis and L. zonatus spp. nov., are described from southwestern China based on morphological and molecular characters. Laetiporus ailaoshanensis is characterized by orange-yellow to reddish orange pileal surface and cream to buff pores when fresh, azonate to faintly zonate pileus, ovoid to ellipsoid basidiospores (5.0-6.2 × 4.0-5.0 µm), and it has been observed only on Lithocarpus. Laetiporus zonatus is characterized by white to cream pileal surface with buff to clay-buff base when fresh, concentrically zonate basidiocarps, ellipsoid to pyriform or drop-shaped basidiospores (5.8-7.2 × 4.3-5.5 µm), and it has been found only on Quercus. The phylogenetic relationships of all recognized Laetiporus species were inferred from a combined dataset of ITS and nLSU-rDNA sequences, and L. ailaoshanensis and L. zonatus represent two new lineages in this group.

Sequence validation for the identification of the white-rot fungi Bjerkandera in public sequence databases.

White-rot fungi of the genus Bjerkandera are cosmopolitan and have shown potential for industrial application and bioremediation. When distinguishing morphological characters are no longer present (e.g., cultures or dried specimen fragments), characterizing true sequences of Bjerkandera is crucial for accurate identification and application of the species. To build a framework for molecular identification of Bjerkandera, we carefully identified specimens of B. adusta and B. fumosa from Korea based on morphological characters, followed by sequencing the internal transcribed spacer region and 28S nuclear ribosomal large subunit. The phylogenetic analysis of Korean Bjerkandera specimens showed clear genetic differentiation between the two species. Using this phylogeny as a framework, we examined the identification accuracy of sequences available in GenBank. Analyses revealed that many Bjerkandera sequences in the database are either misidentified or unidentified. This study provides robust reference sequences for sequence-based identification of Bjerkandera, and further demonstrates the presence and dangers of incorrect sequences in GenBank.

Taxonomy and phylogeny of the genus Megasporoporia and its related genera.

Taxonomic and phylogenetic studies on Megasporoporia s.l. were carried out. Phylogenetic analysis based on ITS and nLSU sequences showed that Megasporoporia s.l. belonging to the core polyporoid clade, however, it is not monophyletic, and four clades were recognized. The Megasporoporia s.s. clade includes M. setulosa and two new species, M. bannaensis and M. minor spp. nov. Two monophyletic clades were segregated from Megasporoporia s.l., and two new genera were established. Megasporia gen. nov. is composed of M. cystidiolophora, M. ellipsoidea, M. hexagonoides, M. major, M. violacea, and two new species, M. guangdongensis and M. hengduanensis spp. nov. Megasporoporiella gen. nov. including M. cavernulosa, M. rhododendri, M. subcavernulosa, and two new species, M. lacerata and M. pseudocavernulosa spp. nov. Megasporoporia quercina grouped with Grammothele fuligo in the Grammothele clade, so it is transferred to Grammothele and a new combination, G. quercina, is proposed. The main morphological characters of Megasporoporia and the two new genera are discussed, and identification keys to the three genera are provided.

Enhancement of autofluorescence of the brown-rot fungus Piptoporus betulinus by metal ions.

The autofluorescence (primary fluorescence, AF) of agar cultures of the brown-rot fungus Piptoporus betulinus was investigated in Zeiss Jenalumar and Nikon Eclipse 8201 fluorescence microscopes at various excitations. The strongest AF of hyphae was found in minimal medium with glucose, where the hyphae exhibited green AF at violet (450 nm) excitation and red AF at green (570 nm) excitation. Addition of metals to cultivation media led to enhanced white-blue AF in the presence of Co (at 450 nm) and yellow to yellow-brown AF at 510 nm. When cultivated with Mn and Zn, enhanced AF of intracellular content was observed. Only a weak signal was found in the presence of Cu and Fe.

Thiamine increases beta-glucosidase production in the newly isolated strain of Fomitopsis pinicola.

AIMS: To isolate a high beta-glucosidase (BGL)-producing strain and to optimize BGL production in the isolated strain. METHODS AND RESULTS: A high BGL-producing strain was isolated and identified as Fomitopsis pinicola KMJ812 based on its morphology and a comparison of sequence of its internal transcribed spacer rDNA gene. To increase BGL production, F. pinicola was supplemented with various vitamins. Supplementation with thiamine (20 mg l(-1)) improved BGL production in F. pinicola cultures by 3.7-fold to give a specific activity of 114.4 micromol min(-1) mg(-1) protein, one of the highest among BGL-producing micro-organisms. The increased production of BGL in the thiamine-supplemented culture was confirmed by 2D electrophoresis followed by MS/MS sequencing. The BGL purified from F. pinicola culture showed the highest catalytic efficiency ever reported. CONCLUSION: Supplemental thiamine remarkably increased BGL production by a novel BGL-producing strain, F. pinicola KMJ812. SIGNIFICANCE AND IMPACT OF THE STUDY: Our results provide a high BGL-producing strain and the production media for BGL production, and should contribute to better industrial production of glucose via biological processes.