Decolorization and biodegradation of melanoidin contained in beet molasses by an anamorphic strain of Bjerkandera adusta CCBAS930 and its mutants.

We used a ligninolytic strain of the white-rot fungus B. adusta CCBAS 930 and its mutants with modified ligninolytic activity to assess their potential to remove of molasses. The analyzed strains have been shown to be able to decolorize 1% or 2% molasses solutions containing brown-colored toxic melanoidins. It was found that the decolorization process was determined by the transition to the stage of production of sporulating aerial mycelium (liquid and agar cultures) coupled with an increase in peroxidase activity, which was accompanied by a decrease in the level of melanoidin, free radicals, and phenolic compounds. Four different peroxidase activities were detected in post-culture liquids, i.e. horseradish-like (HRP-like), manganese-dependent (MnP), lignin (LiP), and versatile (VP) peroxidase activities. The HRP-like peroxidase was characterized by the highest activity. The efficiency of removal of melanoidins from a 1% molasses solution by the parental strain and the mutants was dependent on the culture method. The highest efficiency was noted in immobilized cultures (threefold higher than in the mycelium-free cultures), which was accompanied by stimulation of HRP-like peroxidase activity. Mutant 930-5 was found to be the most effective in the decolorization and decomposition of melanoidin. The HRP-like activity in the immobilized cultures of B. adusta 930-5 was 640-fold higher than in the mycelium-free cultures of the fungus. Moreover, decolorization and biodegradation of melanoidin by B. adusta CCBAS 930 and 930-5 was coupled with detoxification.

Fomitopsis mounceae and F. schrenkii-two new species from North America in the F. pinicola complex.

Two new species, Fomitopsis mounceae and F. schrenkii (Polyporales, Basidiomycota) in the F. pinicola species complex in North America, are described and illustrated. Previous molecular phylogenetic analyses identified three well-delimited lineages that represent F. mounceae and F. ochracea from Canada, the Appalachian Mountains, and the northern United States and F. schrenkii from western and southwestern regions of the United States. Fomitopsis pinicola sensu stricto is restricted to Eurasia and does not occur in North America. Morphological descriptions of basidiocarps and cultures for F. mounceae, F. schrenkii, and F. ochracea are presented. The three species are readily differentiated by nuc rDNA internal transcribed spacer (ITS1-5.8S-ITS2 = ITS) sequence, geographic distribution, and basidiospore size. Polyporus ponderosus H. Schrenk is an earlier illegitimate synonym of F. schrenkii. Both F. mounceae and F. schrenkii have a heterothallic multiallelic incompatibility system.

Real-Time PCR Detection of the Basidiomycetous Fungus Bjerkandera adusta: A Tool to Identify Itraconazole Responder Patients with Unexplained Chronic Cough.

BACKGROUND: Filamentous basidiomycetes (f-BMs) are involved in some unexplained chronic cough (UCC) cases that can be improved by the administration of antifungal agents. The disease concept was termed fungus-associated chronic cough (FACC). The current diagnostic criteria warrant environmental fungi isolation from respiratory specimens, which is hardly conceivable for such fungi. OBJECTIVES: This study aimed to detect the f-BMs Bjerkandera adusta, the most common pathogen in FACC, from respiratory specimens of patients with UCC using real-time polymerase chain reaction (PCR). It also evaluated the applicability of the PCR system to detect antifungal agent responders among patients with unexplained cough. METHODS: The PCR system specific to B. adusta was developed and its utility was evaluated using sputum samples from 23 patients with chronic cough. RESULTS: B. adusta was detected in 10 out of 14 patients with UCC (71.4%), in contrast to only 2 out of 9 patients with non-UCC (22.2%; p < 0.05 with the Fisher's exact test). The copy number of the samples correlated with the therapeutic impact score for cough symptoms following the oral administration of itraconazole. CONCLUSION: Development of the real-time PCR system enabled us to demonstrate that many patients with UCC might be influenced by B. adusta, a fact evidenced by the improvement of symptoms with itraconazole administration in most PCR-positive patients. This method would help in detecting itraconazole responders among patients with UCC when the isolation of f-BMs is not achievable.

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.

Specific detection of Bjerkandera adusta by polymerase chain reaction and its incidence in fungus-associated chronic cough.

Chronic cough is a common symptom at outpatient care. An uncontrollable cough with difficulty in treatment is called chronic idiopathic cough. Recent reports have demonstrated that the presence of basidiomycetous fungi in sputum is an important clinical finding that assists in clarifying the cause of chronic cough in some cases. Research has suggested that Bjerkandera adusta is related to fungus-associated chronic cough (FACC). FACC is defined as a chronic cough associated with basidiomycetous fungi found in induced sputum and can be treated with antifungal medication. B. adusta is one of the basidiomycetous fungi that exist in cosmopolitan environments. The aim of this study was to develop a B. adusta detection method using polymerase chain reaction (PCR) with a specific primer set and to research the incidence of B. adusta in FACC. The new method successfully detected B. adusta from FACC patients. The incidence of B. adusta in FACC was 42.86 %. Antifungal drugs were effective in most cases. Significant differences in treatment duration between B. adusta patients and non-B. adusta patients were observed. It is therefore suggested that the presence of B. adusta may be one of the allergic intractable factors of chronic cough. This finding may provide identifiable differences in clinical manifestations between B. adusta and non-B. adusta in FACC and lead to possible differing remedies to treat the two forms. PCR can specifically detect B. adusta from patients suffering from chronic cough and provides a new diagnosis for FACC associated with B. adusta.

Phylogenetic and phenotypic characterization of Fomes fasciatus and Fomes fomentarius in the United States.

The wood-decay fungi Fomes fasciatus and F. fomentarius share many morphological characters that historically have made species delimitation challenging. We examined morphological, molecular and physiological characters of basidiomata and pure cultures of F. fasciatus and F. fomentarius sampled from multiple plant hosts and geographic regions in the United States to determine whether they support separation of the two species. We find that mean basidiospore size is significantly larger in F. fomentarius and represents the most informative morphological character for delineating the species. Basidiomata and pore-surface shape provided additional resolution of the species, but these characters often overlap and are more variable than basidiospore size. Phylogenetic analyses of ITS and RPB2 sequences suggest that F. fasciatus and F. fomentarius represent distinct evolutionary lineages. The two species share less than 88% maximum identity for the ITS region. Limited intraspecific sequence variation at each locus also was observed. In vitro experiments of hyphal-growth response to a wide range of temperatures support differences in physiology between the two species.

Successful large-scale production of fruiting bodies of Laetiporus sulphureus (Bull.: Fr.) Murrill on an artificial substrate.

Laetiporus sulphureus is an edible wood-rotting basidiomycete fungus whose fruiting bodies contain substances with verified therapeutic evidences and large amounts of α-(1 → 3)-glucan which is used as an effective inducer of microbial α-(1 → 3)-glucanases. However, production of mature fruiting bodies of this species under artificially controlled conditions has not been reported until now. Here, we provide the first report of successful initiation and development of L. sulphureus fruiting bodies in large-scale experiments. Twelve Laetiporus strains were isolated from a natural habitat. A synthetic log production system with a substrate composed of a mixture of sawdust enriched with organic and inorganic additives was developed. It was found that shocking the fungus mycelium with cold water or low temperature was the only suitable method for forced fruiting of L. sulphureus strains. Primordia of two strains were initiated already after 5-6 days from induction, and after another 2 days, they began to develop into fruiting bodies. Carpophores appeared fastest on substrates with high organic supplementation (40-45 %) and a low moisture content (40 %). The resulting mature fruiting bodies reached a weight of 200-300 g. The method of cultivation presented in this paper opens the way to commercial production of this valuable basidiomycete.

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.

The occurrence and rapid discrimination of Fomes fomentarius genotypes by ITS-RFLP analysis.

Sequence comparison of available Fomes fomentarius (L.) J. Kickx f. internal transcribed spacer (ITS) of ribosomal DNA sequences demonstrated genetic non-homogeneity of the species. Multiple sequence alignment indicated the presence of two genotypes with overall similarity of about 97% and a strong statistics support. Rapid and reliable method for discrimination of F. fomentarius genotypes based on restriction digestion of polymerase chain reaction (PCR)-amplified ITS sequences was developed. BseNI and SchI restriction endonucleases were found to clearly discriminate between two F. fomentarius genotypes. The method was used to study the variability in F. fomentarius isolates collected from natural forest reserves in Vihorlat Mountains (East Slovakia). In most localities both genotypes occur concurrently. The isolates belonging to the genotype A were found to be prevalent on beech (Fagus sylvatica), while genotype B tends to be found mainly on other hosts. The grouping of selected isolates was confirmed by sequence analysis. Our results indicate that F. fomentarius includes at least two sympatric cryptic species.

Screening for thermotolerant ligninolytic fungi with laccase, lipase, and protease activity isolated in Mexico.

The State of Hidalgo (Mexico) has a large area of forests known as the Huasteca Hidalguense, with a large variety of microorganisms inhabiting it. They represent an important resource from the ecological and technological point of view because they can be used in a broad variety of industrial processes. Due to the climatic conditions of this region, fungi inhabiting it must be thermophile or, at least, thermotolerant, as temperatures can be higher than 45°C in the summer, declining to 20°C in the winter. Use of ligninolytic fungi relies on their capacity to produce enzymes of industrial interest, a topic that has been under continuous research by academic and industrial investigators. Among the most important enzymes are proteases that are widely used due to their biotechnological applications with a high economic impact. Other enzymes, laccases, peroxidases, and lipases are of interest for the industries of the state of Hidalgo, especially in the textile industry, specifically in effluent processing. Fungi (n=156) were collected in the Huasteca Hidalguense, of which 100 were isolated in potato-dextrose-agar covered plates and maintained in tilted tubes. Afterwards, enzymatic activity (laccase, protease and lipase) was determined in the plates. The purpose was to select those fungi with the highest potential for biotechnological applications. Fungi generally grew at either 30°C or 37°C, and for some isolates enzymatic activities were detected at this higher temperature. Results are presented as the relation between enzymatic activity and growth rate: 60 fungi presented laccase activity, 49 had lipase activity, and none had protease activity. In most cases, enzymatic activity was higher than the growth rate, indicating that the isolated fungi have a great biotechnological potential. Statistical analysis revealed that isolates 31 (Trametes) and 8.1 (unidentified) have a larger potential to be studied as laccase-producing fungi. On the other hand, isolates 144.2 (Fomes), 154 (Trametes), and 147.2 (Pycnoporus) are of interest as lipase activity producers, an activity scarcely studied in this type of microorganisms.

Proteomic and functional analysis of the cellulase system expressed by Postia placenta during brown rot of solid wood.

Brown rot basidiomycetes have an important ecological role in lignocellulose recycling and are notable for their rapid degradation of wood polymers via oxidative and hydrolytic mechanisms. However, most of these fungi apparently lack processive (exo-acting) cellulases, such as cellobiohydrolases, which are generally required for efficient cellulolysis. The recent sequencing of the Postia placenta genome now permits a proteomic approach to this longstanding conundrum. We grew P. placenta on solid aspen wood, extracted proteins from the biodegrading substrate, and analyzed tryptic digests by shotgun liquid chromatography-tandem mass spectrometry. Comparison of the data with the predicted P. placenta proteome revealed the presence of 34 likely glycoside hydrolases, but only four of these--two in glycoside hydrolase family 5, one in family 10, and one in family 12--have sequences that suggested possible activity on cellulose. We expressed these enzymes heterologously and determined that they all exhibited endoglucanase activity on phosphoric acid-swollen cellulose. They also slowly hydrolyzed filter paper, a more crystalline substrate, but the soluble/insoluble reducing sugar ratios they produced classify them as nonprocessive. Computer simulations indicated that these enzymes produced soluble/insoluble ratios on reduced phosphoric acid-swollen cellulose that were higher than expected for random hydrolysis, which suggests that they could possess limited exo activity, but they are at best 10-fold less processive than cellobiohydrolases. It appears likely that P. placenta employs a combination of oxidative mechanisms and endo-acting cellulases to degrade cellulose efficiently in the absence of a significant processive component.

Analysis of expressed sequence tags from the wood-decaying fungus Fomitopsis palustris and identification of potential genes involved in the decay process.

Fomitopsis palustris, a brown-rot basidiomycete, causes the most destructive type of decay in wooden structures. In spite of its great economic importance, very little information is available at the molecular level regarding its complex decay process. To address this, we generated over 3,000 expressed sequence tags (ESTs) from a cDNA library constructed from F. palustris. Clustering of 3,095 high-quality ESTs resulted in a set of 1,403 putative unigenes comprising 485 contigs and 918 singlets. Homology searches based on BlastX analysis revealed that 78% of the F. palustris unigenes had a significant match to proteins deposited in the nonredundant databases. A subset of F. palustris unigenes showed similarity to the carbohydrateactive enzymes (CAZymes), including a range of glycosyl hydrolase (GH) family proteins. Some of these CAZymeencoded genes were previously undescribed for F. palustris but predicted to have potential roles in biodegradation of wood. Among them, we identified and characterized a gene (FpCel45A) encoding the GH family 45 endoglucanase. Moreover, we also provided functional classification of 473 (34%) of F. palustris unigenes using the Gene Ontology hierarchy. The annotated EST data sets and related analysis may be useful in providing an initial insight into the genetic background of F. palustris.

Ecology of coarse wood decomposition by the saprotrophic fungus Fomes fomentarius.

Saprotrophic wood-inhabiting basidiomycetes are the most important decomposers of lignin and cellulose in dead wood and as such they attracted considerable attention. The aims of this work were to quantify the activity and spatial distribution of extracellular enzymes in coarse wood colonised by the white-rot basidiomycete Fomes fomentarius and in adjacent fruitbodies of the fungus and to analyse the diversity of the fungal and bacterial community in a fungus-colonised wood and its potential effect on enzyme production by F. fomentarius. Fungus-colonised wood and fruitbodies were collected in low management intensity forests in the Czech Republic. There were significant differences in enzyme production by F. fomentarius between Betula pendula and Fagus sylvatica wood, the activity of cellulose and xylan-degrading enzymes was significantly higher in beech wood than in birch wood. Spatial analysis of a sample B. pendula log segment proved that F. fomentarius was the single fungal representative found in the log. There was a high level of spatial variability in the amount of fungal biomass detected, but no effects on enzyme activities were observed. Samples from the fruiting body showed high ß-glucosidase and chitinase activities compared to wood samples. Significantly higher levels of xylanase and cellobiohydrolase were found in samples located near the fruitbody (proximal), and higher laccase and Mn-peroxidase activities were found in the distal ones. The microbial community in wood was dominated by the fungus (fungal to bacterial DNA ratio of 62-111). Bacterial abundance composition was lower in proximal than distal parts of wood by a factor of 24. These results show a significant level of spatial heterogeneity in coarse wood. One of the explanations may be the successive colonization of wood by the fungus: due to differential enzyme production, the rates of biodegradation of coarse wood are also spatially inhomogeneous.

Phylogenetic relationships in European Ceriporiopsis species inferred from nuclear and mitochondrial ribosomal DNA sequences.

The aim of this work was to clarify taxonomy and examine evolutionary relationships within European Ceriporiopsis species using a combined analysis of the large subunit (nLSU) nuclear rRNA and small subunit (mtSSU) mitochondrial rRNA gene sequences. Data from the ITS region were applied to enhance the view of the phylogenetic relationships among different species. The studied samples grouped into four complex clades, suggesting that the genus Ceriporiopsis is polyphyletic. The generic type Ceriporiopsis gilvescens formed a separate group together with Ceriporiopsis guidella and Phlebia spp. in the phlebioid clade. In this clade, the closely related species Ceriporiopsis resinascens and Ceriporiopsis pseudogilvescens grouped together with Ceriporiopsis aneirina. C. resinascens and C. pseudogilvescens have identical LSU and SSU sequences but differ in ITS. Ceriporiopsis pannocincta also fell in the phlebioid clade, but showed closer proximity to Gloeoporus dichrous than to C. gilvescens or C. aneirina-C. pseudogilvescens-C. resinascens group. Another clade was composed of a Ceriporiopsis balaenae-Ceriporiopsis consobrina group and was found to be closely related to Antrodiella and Frantisekia, with the overall clade highly reminiscent of the residual polyporoid clade. The monotypic genus Pouzaroporia, erected in the past for Ceriporiopsis subrufa due to its remarkable morphological differences, also fell within the residual polyporoid clade. Ceriporiopsis subvermispora held an isolated position from the other species of the genus. Therefore, the previously proposed name Gelatoporia subvermispora has been adopted for this species. Physisporinus rivulosus appeared unrelated to two other European Physisporinus species. Moreover, Ceriporiopsis (=Skeletocutis) jelicii grouped in a separate clade, distinct from Ceriporiopsis species. Finally, the ITS data demonstrated the proximity of some Ceriporiopsis species (Ceriporiopsis portcrosensis and Ceriporiopsis subsphaerospora) to Skeletocutis amorpha.

Laccase and its role in production of extracellular reactive oxygen species during wood decay by the brown rot basidiomycete Postia placenta.

Brown rot basidiomycetes initiate wood decay by producing extracellular reactive oxygen species that depolymerize the structural polysaccharides of lignocellulose. Secreted fungal hydroquinones are considered one contributor because they have been shown to reduce Fe(3+), thus generating perhydroxyl radicals and Fe(2+), which subsequently react further to produce biodegradative hydroxyl radicals. However, many brown rot fungi also secrete high levels of oxalate, which chelates Fe(3+) tightly, making it unreactive with hydroquinones. For hydroquinone-driven hydroxyl radical production to contribute in this environment, an alternative mechanism to oxidize hydroquinones is required. We show here that aspen wood undergoing decay by the oxalate producer Postia placenta contained both 2,5-dimethoxyhydroquinone and laccase activity. Mass spectrometric analysis of proteins extracted from the wood identified a putative laccase (Joint Genome Institute P. placenta protein identification number 111314), and heterologous expression of the corresponding gene confirmed this assignment. Ultrafiltration experiments with liquid pressed from the biodegrading wood showed that a high-molecular-weight component was required for it to oxidize 2,5-dimethoxyhydroquinone rapidly and that this component was replaceable by P. placenta laccase. The purified laccase oxidized 2,5-dimethoxyhydroquinone with a second-order rate constant near 10(4) M(-1) s(-1), and measurements of the H(2)O(2) produced indicated that approximately one perhydroxyl radical was generated per hydroquinone supplied. Using these values and a previously developed computer model, we estimate that the quantity of reactive oxygen species produced by P. placenta laccase in wood is large enough that it likely contributes to incipient decay.

Isolation and characterization of a novel lignocellulose decomposing fungal strain.

A strain F1 with high cellulase activity obtained from the deadwood stack was characterized as Ceriporia lacerate by examination of the general taxonomical characteristics and phylogenetic sequence analysis of rDNA ITS gene. The endoglucanase (EG) and filter paper cellulase (FPase) activities of the strain showed remarkable stability in the pH range of 4.0-7.0, and maintained about their maximal value of 76% and 50% after incubation at 70 degrees C for 6 h respectively. The strain grew particularly well with CMC-Na (1.0%) and yeast extract (0.4%) at 28 degrees C (pH 6.0) in flasks stirred at 150 x g for 6 days. Based on the thermostability and pH stability of cellulase, the strain appears to have potential in industrial applications and bioresource utilization.

Is Bjerkandera adusta Important to fungus-associated chronic cough as an allergen? Eight cases' reports.

BACKGROUND: Recently, we have reported a new clinical disease concept called fungus-associated chronic cough (FACC), which entailed the following manifestations: (1) chronic cough; (2) the presence of environmental fungi, particularly basidiomycetous (BM) fungi, in the sputum; and (3) good clinical response to antifungal drugs. To clarify the relationship between the exposure to environmental fungi and the development of cough attacks, we reviewed the clinical records of patients with FACC and performed a molecular biological analysis of the BM fungi. METHODS: We successfully selected 8 patients with chronic cough, wherein a sputum culture yielded B. adusta beforehand; moreover, we conducted allergological tests such as the immediate-type skin test, a serological test, bronchoprovocation test, and lymphocyte stimulation test (LST), using the antigenic solution of B. adusta. The efficacy of individualized therapy and the clinical manifestations in the eight patients were examined. RESULTS: All the eight patients were diagnosed with FACC. Although three patients who did not show a positive reaction to the bronchoprovocation test or LST showed excellent clinical response to anti-fungal drugs; other 5 patients who showed a positive reaction to the bronchoprovocation test and/or LST seemed to be more intractable because of taking a longer time for complete remission and more frequent recurrence of cough. CONCLUSION: It was suggested that so-called allergic fungal cough (AFC), which is characterized by sensitization to B. adusta, may be included in a part of chronic intractable cough.

Disseminated Oxyporus corticola infection in a German shepherd dog.

The filamentous basidiomycetous fungus, Oxyporus corticola, has not previously been reported in the human or veterinary medical literature. Identification of this organism as the etiologic agent of fungal osteomyelitis and multiorgan dissemination in a German shepherd dog was confirmed by comparison of ITS and D1/D2 sequences with known isolates.

Isolation and screening of natural organic matter-degrading fungi.

Drinking water quality and its treatment are negatively impacted by the presence of coloured natural organic matter (NOM) derived from the breakdown of animal and plant materials. Ligninolytic fungi (i.e., white rot fungi - WRF) secrete non-specific oxidative enzymes that can oxidise a wide range of recalcitrant organic compounds. The potential for these organisms to decolourise concentrated aquatic NOM was investigated. Twenty-one isolates from diverse fungal genera were screened using NOM plate assays. Four WRF strains: Trametes sp., Polyporus sp., Trametes versicolor ATCC 7731 and Bjerkandera adusta, which displayed good NOM decolourisation on solid medium were further investigated in shake-flask culture using concentrated NOM as the only source of nutrients. Of these, B. adusta demonstrated the greatest decolourisation (65% for 100 mg C L(-1) NOM). NOM decolourisation coincided with ligninolytic enzyme activity and decrease in average molecular weight of NOM. The expression of the oxidative enzymes (manganese peroxidase (MnP), lignin peroxidase and laccase (Lac)) varied with fungal strain. The enzyme activities of Polyporus sp. and the two Trametes strains were significantly greater than those of B. adusta, although their decolourisation was less. For the Trametes and Polyporus sp., Lac activity was greatest, whereas for B. adusta MnP activity was greatest, suggesting its predominant role in the decolourisation process. This research demonstrates the significant potential for WRF in NOM removal so long as the enzyme activity can be controlled.