Reliability of poly B-411, a polymeric anthraquinone-based dye, in determining the rot type caused by wood-inhabiting fungi

Multiplex PCR for species discrimination of Sclerotiniaceae by novel laccase introns

Common PCR-based targets for the identification of filamentous fungi and yeasts are the sequences of the internal transcribed spacer region (ITS1, 5.8S rDNA, ITS2). Within the Sclerotiniaceae the ITS-region is homogenous and the identification is almost impossible. Furthermore, the lack of IGS-data (intergenic spacer region) requires new specific marker genes for a rapid identification of phytopathogenic Sclerotiniaceae. We sequenced and analyzed new laccase2 (lcc2) genes from the phylogenetically related Sclerotinia sclerotiorum (Lib.) de Bary, Sclerotinia minor Jagger, and Monilinia fructigena Honey. Comparative analysis revealed remarkable differences in length and sequence compared to the well-known lcc2 gene of Botrytis cinerea caused by a different number of intron sequences. These results gave us the possibility to develop a primer set for a rapid multiplex PCR-identification of different species in environmental samples, e.g. wine, fruit, or soil. Therefore, the application of this technique allows the simultaneous detection of different phytopathogenic Sclerotiniaceae in complex microbiota like decomposed herbal material. In the present study prevailed problems in the field of a general identification of fungal specimen are highlighted.

Necrotrophic mycoparasitism of Botrytis cinerea by cellulolytic and ligninocellulolytic Basidiomycetes

Twenty-six isolates representing 17 species of aphyllophoraceous, wood-decaying Basidiomycetes and five species of agaricoid, turf-borne, thatch-decaying Basidiomycetes were screened for their abilities to degrade cellulose, lignin, and melanin by using colorimetric degradation assays on agar media. Selected ligninocellulolytic Basidiomycetes capable of degrading melanin were screened for antagonism of Botrytis cinerea Per.:Fr. The greatest inhibition of Botrytis colony and hyphal growth in vitro was observed in confrontations with Irpex lacteus (Fr.) Fr., Trametes versicolor (L.:Fr.) Pilat, and Chondrostereum purpureum (Pers.:Fr.) Pouzar. Hyphal interference and necrotrophic mycoparasitism by these ligninocellulolytic Basidiomycetes were recognized microscopically as coagulation and degeneration of Botrytis cytoplasm and as coiling and invasion of hyphae, conidiophores, and conidia, respectively. Sclerotia of B. cinerea were killed and parasitized in agar media, straw mulch, or moist sand infested separately with these three mycoparasites.

Lignin degrading system of white-rot fungi and its exploitation for dye decolorization

With global attention and research now focused on looking for the abatement of pollution, white-rot fungi is one of the hopes of the future. The lignin-degrading ability of these fungi have been the focus of attention for many years and have been exploited for a wide array of human benefits. This review highlights the various enzymes produced by white-rot fungi for lignin degradation, namely laccases, peroxidases, aryl alcohol oxidase, glyoxal oxidase, and pyranose oxidase. Also discussed are the various radicals and low molecular weight compounds that are being produced by white-rot fungi and its role in lignin degradation. A brief summary on the developments in research of decolorization of dyes using white-rot fungi has been made.

Production and Characterization of Trametes versicolor Mutants Unable To Bleach Hardwood Kraft Pulp

Protoplasts of the monokaryotic strain 52J of Trametes versicolor were treated with UV light and screened for the inability to produce a colored precipitate on guaiacol-containing agar plates. Mutants unable to oxidize guaiacol had absent or very low secretion of laccase and manganese peroxidase (MnP) proteins. All isolates unable to secrete MnP were also unable to bleach or delignify kraft pulp. One mutant strain, M49, which grew normally but did not oxidize guaiacol, was tested further with a number of other substrates whose degradation has been associated with delignification by white rot fungi. Compared with the parent, 52J, mutant M49, secreting no MnP and low laccase, could not brighten or delignify kraft pulp, produced less ethylene from 2-keto methiolbutyric acid, released much less (sup14)CO(inf2) from [(sup14)C]DHP (a synthetic lignin-like polymerizate), and produced much less methanol from pulp. This mutant also displayed decreased abilities to oxidize the dyes poly B-411, poly R-478, and phenol red compared with the wild-type strain and was also unable to decolorize kraft bleachery effluent or mineralize its organochlorine. Addition of purified MnP in conjunction with H(inf2)O(inf2), MnSO(inf4), and an Mn(III) chelator to M49 cultures partially restored methanol production, pulp delignification, and biobleaching in some cases.