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Research has been conducted on Phanerochaete chrysosporiumcellulase genes. The cloning and characterization of these genes have been carried out, and the results demonstrate that their transcript levels are higher in cellulose-grown than in glucose-grown cultures.

Research has been conducted on Gloeophyllum trabeum, a brown-rot basidiomycete which uses quinone redox cycle to produce a biodegradative system component Fenton reagent. The characterization of the quinone reductase, mRNA and gene encoding this enzyme from G. trabeum has been carried out and the results are reported.

Research has been conducted on the peroxidase-encoding gene and its corresponding cDNA from the white-rot basidiomycete Trametes versicolor PRL 572. The transcripts of this gene have been investigated and the results suggest that plant and fungal peroxidases are produced via the ancient duplication and folding of two structural domains.

Researchers illustrate the use of cultures derived from a single basidiospore of Phanerochaete chrysosporium for genetic analysis of transposons. These haploid homokaryons contain a single nuclear type, unlike the two different nuclear types in dikaryons.

Reverse transcriptase polymerase chain reaction and magnetic capture techniques were employed in the quantification of the transcripts of cellobiohydrolase and cellobiose dehydrogenase in Phanerochaete chrysosporium-colonized wood chips. The transcript patterns were found to be markedly different from that formerly observed on defined media supplemented with glucose or cellulose. Transcripts of some lignin peroxidase and manganese peroxidase genes were also observed in the wood chips.

Two white rot fungi, Phanerochaete sordida and Ceriporiopsis subvermispora, contain lignin peroxidase (LiP)-like sequences but show no LiP activity. The LiP-like genes were identified by PCR amplification of the P. sordida and C. subvermispora genomes. Reverse transcription-PCR shows that the LiP-like gene of P. sordida is transcribed under ligninolytic conditions. However, the transcript is different from the genomic clone. There is no transcription of the C. subvermispora LiP-like gene.

The nucleotide sequences of the small-subunit rRNA genes of 12 geographically diverse Aureobasidium pullulans strains are analyzed to evaluate the vulnerability of rRNA to A. pullulans-specific oligonucleotide probes. Results show that a short oligonucleotide with a single nucleotide mismatch to the target sequence can differentiate strains. This finding suggests that the oligonucleotide probes can be used in quantifying fungi in leaf surface and other microbial communities.

A Phanerochaete chrysosporium manganese peroxidase gene in Aspergillus oryzae (A. oryzae) has been expressed through the use of a similar construct. Expression was achieved through the fusion of mature cDNA of mnp1 with the A. oryzae Taka amylase promoter and secretion signal. The expression of rMnP in A. oryzae provides pure, active enzymes suitable for mechanistic studies.

A cDNA clone (glx-2c), of the white rot fungus Phanerochaete chrysosporium, encoding glyoxal oxidase was identified and its nucleotide sequence was found to be different from that of the previously known clone glx-1c. Genomic clones corresponding to both cDNAs were sequenced and were found to be 98% identical. The predicted proteins were unlike only in a single residue. Their structural variants were found to be alleles.

Phanerochaete sordida, a white rot fungus, generates ligninolytic enzymes in liquid culture, from which three distinct, yet similar manganese peroxide enzymes (MnP) are detected. The three MnP enzymes exhibit similar activity when the pH ranges between 3.0 and 6.0, with optimal pHs ranging from 4.5 to 5.0. MnP enzymes are separate gene products, but P. sordida often reveals allelic variants in these enzymes.

Phanerochaete chrysosporium produces isozymic forms of lignin peroxidase (LiP) which are encoded by a family of structurally related genes. The pattern of regulation of gene expression of Lip in P. chrysosporium was elucidated. Northern blot analysis showed that the levels of transcripts for GLG4, V4 and GLG5 are dependent on culture conditions. The gene for GLG4 was mapped to a dimorphic chromosome separate from the other LiP genes.

Research was conducted to examine the expression of Phanerochaete chrysosporium genes encoding lignin peroxidases, manganese peproxidases, and glyoxal oxidase in wood. Extraction of poly(A) RNA was done from colonized wood chips using magnetic capture while specific transcripts were quantified through competitive reverse transcriptase PCR. Results suggest that genes previously shown to be highly expressed under a wide range of cultural conditions are unlikely to play a significant role in biopulping performance on aspen.

The use of competitive reverse transcription-polymerase chain reaction (RT-PCR) techniques help the detecting and sequencing of cbh1-4 gene which encodes the major cellobiohydrolases (CBH) of the white rot fungus Phanerochaete chrysosporium. A study of the quantity of cbh1-3, cbh1-4, cbh1-5 and cbh1-6 transcripts under cellulose induction reveals that cbh1-4 is the dominant transcript which indicates that the major isozyme of the fungus, CBH1, is encoded by cbh1-4. Amino acid sequences of the cbh1-4 gene are similar to the peptide sequences of isozyme CBH1.

A study was conducted to demonstrate that aspen wood undergoing decay by the oxalate producer basidiomycetes Postia placenta contained both 2,5-dimethoxyhydroquinone and laccase activity. The estimated quantify of reactive oxygen species produced by P. placenta laccase in wood which large enough possibly contributed to incipient decay.

A protocol for identification and differentiation of allelic variants of the lignin peroxidase gene in Phanerochaete chrysosporium was developed and is presented. The method involves genomic DNA amplification by the polymerase chain reaction. The amplified genes are then probed with allele-specific oligonucleotides using the Southern blot technique. This protocol allows rapid identification of lignin peroxidase genes and alleles and is useful for classifying P. chrysosporium strains.

The white rot basidiomycete Phanerochaete chrysosporium on cellulose or glucose as the carbon source are grown and monitored to assess the mineralization of a [14.sup.C-labeled] synthetic lignin by ligninolytic competence. The results showed that the cellulose-grown cultures are ligninolytic while the glucose-grown ones are not and the proteomic analysis of partially purified plasma membranes from ligninolytic P. chrysosporium are most likely associated with the outer envelope of the fungus.

Study done to identify and characterize the glucose-oxidizing activity of Phanerochaete chrysosporium grown on solid substrate is reported. 13C-nuclear magnetic resonance (NMR) and 13C-labeled glucose were used to unambiguously distinguish glucose 1-oxidase (GOX) from pyranose 2-oxidase (POX). High levels of pox transcript were found under carbon-starved ligninolytic conditions but not under nutrient sufficiency and thus, this regulation pattern supports the evidence that POX has a role in lignocellulose degradation.

Research reveals that the laccase activity of Phanerochaete chrysosporium is due to a new multicopper oxidase distinct from fungal laccase as shown by the identification of the clustered multicopper oxidase-encoding sequences.

Pyranose 2-oxidase (POX) was recovered from Phanerochaete chrysosporium BKM-F-1767 solid substrate culture using mild extraction conditions and was purified. 13C-nuclear magnetic resonance confirmed production of D-arabino-hexos-2-ulose (glucosone) from n-glucose with the oxidase. Peptide fingerprints generated by liquid chromatography-tandem mass spectrometry of tryptic digests and analysis of the corresponding cDNA revealed a structurally unusual sequence for the P. chrysosporium POX. Relatively high levels of pox transcript were detected under carbon-starved culture conditions but not under nutrient sufficiency. This regulation pattern is similar to that observed for lignin peroxidases, manganese peroxidases, and glyoxal oxidase of P. chrysosporium, supporting evidence that POX has a role in lignocellulose degradation. [ABSTRACT FROM AUTHOR]

Reports on the transcript analysis of genes encoding a family 61 endoglucanase and a putative membrane-anchored family 9 glycosyl hydrolase from Phanerochaete chrysosporium. Cloning and characterization of Phanerochaete chrysosporium cellulase genes; Transcript analysis; Nucleotide sequence accession numbers.

Identifies quinone reductase expressed by Gloeophyllum trabeum under conditions eliciting high levels of quinone redox recycling. Presence of molecule of flavin mononucleotide in the enzymes; Affinity of reductase for quinones; Role of G. trabeum quinone reductase in quinone detoxification.