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Fungal biotechnology is set to play a keystone role in the emerging bioeconomy, notably to address pollution issues arising from human activities. Because they preserve biological diversity, Biological Resource Centres are considered as critical infrastructures to support the development of biotechnological solutions. Here, we report the first large-scale phenotyping of more than 1,000 fungal strains with evaluation of their growth and degradation potential towards five industrial, human-designed and recalcitrant compounds, including two synthetic dyes, two lignocellulose-derived compounds and a synthetic plastic polymer. We draw a functional map over the phylogenetic diversity of Basidiomycota and Ascomycota, to guide the selection of fungal taxa to be tested for dedicated biotechnological applications. We evidence a functional diversity at all taxonomic ranks, including between strains of a same species. Beyond demonstrating the tremendous potential of filamentous fungi, our results pave the avenue for further functional exploration to solve the ever-growing issue of ecosystems pollution., (© 2021. The Author(s).)

We recovered 195 fungal isolates from the sediments of different lakes in the Antarctic Peninsula, which were screened to detect bioactive compounds. Forty-two taxa belonging to the phyla Ascomycota, Basidiomycota, and Mortierellomycota were identified. Thelebolus globosus, Antarctomyces psychrotrophicus, Pseudogymnoascus verrucosus, Vishniacozyma victoriae, and Phenoliferia sp. were found to be the most prevalent. The fungal assemblages showed high diversity and richness, but low dominance values. However, the diversity indices and fungal distribution ranged according to the different lake sediments. Sixty fungal extracts displayed at least one biological activity against the evaluated targets. Among them, Pseudogymnoascus destructans showed selective trypanocidal activity, Cladosporium sp. 1 and Trichoderma polysporum showed antifungal activity, and Pseudogymnoascus appendiculatus and Helotiales sp. showed high herbicidal activity. We detected a rich and diverse fungal community composed of cold cosmopolitan and psychrophilic endemic taxa recognized as decomposers, symbiotics, pathogens, and potential new species, in the sediments of Antarctic lakes. The dynamics and balance of this fungal community represents an interesting aquatic web model for further ecological and evolutionary studies under extreme conditions and potential climate changes in the regions. In addition, we detected fungal taxa and isolates able to produce bioactive compounds that may represent the source of prototype molecules for applications in medicine and agriculture., (Copyright © 2020 British Mycological Society. Published by Elsevier Ltd. All rights reserved.)

Three wastewater treatment plants (WWTPs) located in Gauteng province in South Africa were investigated to determine the diversity, co-occurrence and implications of their fungal communities using illumina sequencing platform and network analysis. Phylogenetic taxonomy revealed that members of the fungal communities were assigned to 6 phyla and 361 genera. Basidiomycota and Ascomycota were the most abundant phyla, dominated by the genera Naumovozyma, Pseudotomentella, Derxomyces, Ophiocordyceps, Pulchromyces and Paecilomyces. Phylogenetic analysis revealed the existence of fungal OTUs related to class lineages such as Agaricomycetes, Eurotiomycetes and Sordariomycetes indicating new fungal diversity in WWTPs. Dominant and rare fungal genera that can potentially be used in bioremediation such as Trichoderma, Acremonium, Talaromyces, Paecilomyces, cladophialophora and Saccharomyces were detected. Conversely, genera whose members are known to be pathogenic to human and plant such as Olpidium, Paecilomyces, Aspergillus, Rhodotorula, Penicillium, Candida, Synchytrium, Phyllosticta and Mucor were also detected in all WWTPs. Phylotype analysis confirmed that some fungal phylotypes were highly similar to the reported fungal pathogens of concern. Co-occurrence network analysis revealed that the fungal genera such as Minimedusa, Glomus, Circinella, Coltricia, Caloplaca, Phylosticta, Peziza, Candida, and Hydnobolites were the major networking hub in the WWTPs. The overall results in this study highlighted that WWTPs represent a potential source of beneficial fungi for bioremediation of pollutants in the ecosystem and the need to consider human and plant fungal pathogens during safety evaluation of treated wastewater for reuse.

Aims: We aimed to expand the microbial biocatalyst platform to generate essential oxyfunctionalized standards for pharmaceutical, toxicological and environmental research. In particular, we examined the production of oxyfunctionalized nonsteroidal anti-inflammatory drugs (NSAIDs) by filamentous-fungi., Methods and Results: Four NSAIDs; diclofenac, ibuprofen, naproxen and mefenamic acid were used as substrates for oxyfunctionalization in a biocatalytic process involving three filamentous-fungi strains; Beauveria bassiana, Clitocybe nebularis and Mucor hiemalis. Oxyfunctionalized metabolites that are major degradation intermediates formed by Cytochrome P450 monooxygenases in human metabolism were produced in isolated yields of up to 99% using 1 g l -1 of substrate. In addition, a novel compound, 3',4'-dihydroxydiclofenac, was produced by B. bassiana. Proteomic analysis identified CYP548A5 that might be responsible for diclofenac oxyfunctionalization in B. bassiana., Conclusions: Efficient fungi catalysed oxyfunctionalization was achieved when using NSAIDs as substrates. High purities and isolated yields of the produced metabolites were achieved., Significance and Impact of the Study: The lack of current efficient synthetic strategies for oxyfunctionalization of NSAIDs is a bottleneck to perform pharmacokinetic, pharmacodynamic and toxicological analysis for the pharmaceutical industry. Additionally, oxyfunctionalized derivatives are needed for tracking the fate and impact of such metabolites in the environment. Herein, we described a fungi catalysed process that surpasses previously reported strategies in terms of efficiency, to synthesize oxyfunctionalized NSAIDs., (© 2019 The Society for Applied Microbiology.)

We compared the δ 13 C and δ 15 N of forest material with an extensive sporocarp collection to elucidate the role of litter, wood and soil as fungal carbon and nitrogen sources in Finnish boreal Picea abies-dominated forests. Ectomycorrhizal Hydnum and Cortinarius had higher δ 15 N than other ectomycorrhizal fungi, suggesting use of 15 N-enriched, deeper nitrogen. Russula had lower δ 15 N than other ectomycorrhizal fungi and resembled some litter decay genera, suggesting use of litter-derived nitrogen. There was little variation in δ 15 N among other genera of ectomycorrhizal fungi, indicating limited functional diversity in nitrogen use. Saprotrophic Leotia, Gymnopus, Hypholoma, Pholiota, Rhodocollybia and Calocera had δ 15 N values similar to ectomycorrhizal fungi, indicating overlap in use of older nitrogen from soil or roots or use of newly fixed nitrogen. Genera of litter and wood decay fungi varied up to 6‰ in δ 13 C and 10‰ in δ 15 N, suggesting large differences in carbon and nitrogen sources and processing. Similar δ 13 C between white and brown rot wood decay fungi also suggest that white rot fungi do not use lignin-derived carbon. Together, these δ 13 C and δ 15 N patterns of fungi from Finnish boreal forests enhance our knowledge of fungal functional diversity and indicate broad use of litter, wood and soil resources., (Copyright © 2019 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Many trees form ectomycorrhizal symbiosis with fungi. During symbiosis, the tree roots supply sugar to the fungi in exchange for nitrogen, and this process is critical for the nitrogen and carbon cycles in forest ecosystems. However, the extents to which ectomycorrhizal fungi can liberate nitrogen and modify the soil organic matter and the mechanisms by which they do so remain unclear since they have lost many enzymes for litter decomposition that were present in their free-living, saprotrophic ancestors. Using time-series spectroscopy and transcriptomics, we examined the ability of two ectomycorrhizal fungi from two independently evolved ectomycorrhizal lineages to mobilize soil organic nitrogen. Both species oxidized the organic matter and accessed the organic nitrogen. The expression of those events was controlled by the availability of glucose and inorganic nitrogen. Despite those similarities, the decomposition mechanisms, including the type of genes involved as well as the patterns of their expression, differed markedly between the two species. Our results suggest that in agreement with their diverse evolutionary origins, ectomycorrhizal fungi use different decomposition mechanisms to access organic nitrogen entrapped in soil organic matter. The timing and magnitude of the expression of the decomposition activity can be controlled by the below-ground nitrogen quality and the above-ground carbon supply.

Thermophilic fungi can represent a rich source of industrially relevant enzymes. Here, 105 fungal strains capable of growing at 50 °C and pH 2.0 were isolated from compost and decaying plant matter. Maximum growth temperatures of the strains were in the range 50 °C to 60 °C. Sequencing of the internal transcribed spacer (ITS) regions indicated that 78 fungi belonged to 12 species of Ascomycota and 3 species of Zygomycota, while no fungus of Basidiomycota was detected. The remaining 27 strains could not be reliably assigned to any known species. Phylogenetically, they belonged to the genus Thielavia, but they represented 23 highly divergent genetic groups different from each other and from the closest known species by 12 to 152 nucleotides in the ITS region. Fungal secretomes of all 105 strains produced during growth on untreated rice straw were studied for lignocellulolytic activity at different pH and temperatures. The endoglucanase and xylanase activities differed substantially between the different species and strains, but in general, the enzymes produced by the novel Thielavia spp. strains exhibited both higher thermal stability and tolerance to acidic conditions. The study highlights the vast potential of an untapped diversity of thermophilic fungi in the tropics.

Background: Many small peptides regulate eukaryotic cell biology. In fungi, some of these peptides are produced after KEX2 protease activity on proteins displaying repetitions of identical or nearly identical motifs. Following this endoprotease activity, peptides are released in the extracellular space. This type of protein maturation is involved in the production of the α-type sexual pheromone in Ascomycota. In other cases, this processing allows the production of secreted peptides regulating fungal cell wall structure or acting as mycotoxins. In this work, we report for the first time a genome-wide search of KEX2-processed repeat proteins that we call KEPs. We screened the secreted proteins of 250 fungal species to compare their KEP repertoires with regard to their lifestyle, morphology or lineage., Results: Our analysis points out that nearly all fungi display putative KEPs, suggesting an ancestral origin common to all opisthokonts. As expected, our pipeline identifies mycotoxins but also α-type sexual pheromones in Ascomycota that have not been explored so far, and unravels KEP-derived secreted peptides of unknown functions. Some species display an expansion of this class of proteins. Interestingly, we identified conserved KEPs in pathogenic fungi, suggesting a role in virulence. We also identified KEPs in Basidiomycota with striking similarities to Ascomycota α-type sexual pheromones, suggesting they may also play alternative roles in unknown signalling processes., Conclusions: We identified putative, new, unexpected secreted peptides that fall into different functional categories: mycotoxins, hormones, sexual pheromones, or effectors that promote colonization during host-microbe interactions. This wide survey will open new avenues in the field of small-secreted peptides in fungi that are critical regulators of their intimate biology and modulators of their interaction with the environment.

The scarcity of available drinking water has led the researchers to develop novel and cost-effective ways of bioremediation process for wastewater treatment. Bioremediation is a cost-effective and environmentally sound method for the removal of toxic compounds. Such approach is not only a chemical-less effort but also an energy savior. In the present work Phlebia acerina, a white rot wood rotting fungi have been used to degrade the toxic wastewater pollutants. Congo Red (CR) and Eriochrome Black T (EBT) have been selected as model pollutants to test the wastewater cleaning ability of the fungus. The Lignin modifying enzyme (LME) and Cellulolytic enzyme assays (CMC) potential of Phlebia acerina helped in understanding the dye degradation mechanism. Under the optimum conditions, the fungi was able to degrade as high as 92.4% CR while the EBT was degraded to a maximum of 50%. Phlebia acerina was found to show first-order kinetics of dyes degradation. Further, the seed germination and antimicrobial assay of treated and untreated water were carried out in order to establish the formation of non-toxic end product after degradation., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

White-rot fungi are renowned for their remarkable potential to degrade a wide range of organic pollutants. They are applicable in standard bioreactors offering both the use of the continuous mode of action and easy upscaling of the biodegradation process. The recent advance in this field consisted in the use of various fungi and different types of reactors in the treatment of real wastewaters. Most degradation studies involving white-rot fungi carried out so far used controlled, aseptic conditions. However, during bioremediation of real wastewaters, the degradation capacity of the fungi would be significantly affected by autochthonous microorganisms. Consequently, for the development of sustainable bioremediation technologies, it is important to understand the mechanisms involved in the intermicrobial interactions occurring during the bioremediation process. This review summarizes recent applications of white-rot fungi to biodegradation of recalcitrant organopollutants under non-sterile conditions describing the invading microorganism(s) and the way how they affect the stability and degradation efficiency of the fungal bioreactor cultures. In addition, studies where fungal cultures were exposed to defined microbial stress are also reported documenting the effect and mechanisms of microbial interactions. Advanced OMICs techniques, specifically the genomics and metabolomics analyses, are suggested to help in identification of the invading microorganisms and in discovery of mechanisms taking part in the interspecific interactions.

Sugar transport is of the utmost importance for most cells and is central to a wide range of applied fields. However, despite the straightforward in silico assignment of many novel transporters, including sugar porters, to existing families, their exact biological role and evolutionary trajectory often remain unclear, mainly because biochemical characterization of membrane proteins is inherently challenging, but also owing to their uncommonly turbulent evolutionary histories. In addition, many important shifts in membrane carrier function are apparently ancient, which further limits our ability to reconstruct evolutionary trajectories in a reliable manner. Here, we circumvented some of these obstacles by examining the relatively recent emergence of a unique family of fungal sugar facilitators, related to drug antiporters. The former transporters, named Ffz, were previously shown to be required for fructophilic metabolism in yeasts. We first exploited the wealth of fungal genomic data available to define a comprehensive but well-delimited family of Ffz-like transporters, showing that they are only present in Dikarya. Subsequently, a combination of phylogenetic analyses and in vivo functional characterization was used to retrace important changes in function, while highlighting the evolutionary events that are most likely to have determined extant distribution of the gene, such as horizontal gene transfers (HGTs). One such HGT event is proposed to have set the stage for the onset of fructophilic metabolism in yeasts, a trait that according to our results may be the metabolic hallmark of close to 100 yeast species that thrive in sugar rich environments., (© The Author 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Fungal lignocellulolytic enzymes are promising agents for oxidizing pollutants. This study investigated degradation of Number 6 "Bunker C" fuel oil compounds by the white-rot fungi Irpex lacteus, Trichaptum biforme, Phlebia radiata, Trametes versicolor, and Pleurotus ostreatus (Basidiomycota, Agaricomycetes). Averaging across all studied species, 98.1%, 48.6%, and 76.4% of the initial Bunker C C10 alkane, C14 alkane, and phenanthrene, respectively were degraded after 180 days of fungal growth on pine media. This study also investigated whether Bunker C oil induces changes in gene expression in the white-rot fungus Punctularia strigosozonata, for which a complete reference genome is available. After 20 days of growth, a monokaryon P. strigosozonata strain degraded 99% of the initial C10 alkane in both pine and aspen media but did not affect the amounts of the C14 alkane or phenanthrene. Differential gene expression analysis identified 119 genes with ≥ log2(2-fold) greater expression in one or more treatment comparisons. Six genes were significantly upregulated in media containing oil; these genes included three enzymes with potential roles in xenobiotic biotransformation. Carbohydrate metabolism genes showing differential expression significantly accumulated transcripts on aspen vs. pine substrates, perhaps reflecting white-rot adaptations to growth on hardwood substrates. The mechanisms by which P. strigosozonata may degrade complex oil compounds remain obscure, but degradation results of the 180-day cultures suggest that diverse white-rot fungi have promise for bioremediation of petroleum fuels.

This study investigated the diversity and host component-transforming activity of endophytic fungi in medicinal plant Kadsura angustifolia. A total of 426 isolates obtained were grouped into 42 taxa belonging to Fungi Imperfecti (65.96%), Ascomycota (27.00%), Zygomycota (1.64%), Basidiomycota (0.47%) and Mycelia Sterilia (4.93%). The abundance, richness, and species composition of endophytic assemblages were significantly dependent on the tissue and the sampling site. Many phytopathogenic species associated with healthy K. angustifolia were found prevalent. Among them, Verticillium dahliae was dominant with 16.43% abundance. From 134 morphospecies selected, 39 showed remarkable biocatalytic activity and were further identified as species belonging to the genera Colletotrichum, Eupenicillium, Fusarium, Hypoxylon, Penicillium, Phomopsis, Trametes, Trichoderma, Umbelopsis, Verticillium and Xylaria on the basis of the sequence analysis of the internal transcribed spacer (ITS1-5.8S-ITS2). The results obtained in this work show that K. angustifolia is an interesting reservoir of pathogenic fungal species, and could be a community model for further ecological and evolutionary studies. Additionally, the converting potency screening of some endophytic fungi from this specific medicinal plant may provide an interesting niche on the search for novel biocatalysts., (Copyright © 2014 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.)

Four white rot fungi namely Phanerochaete chrysosporium, Phlebia floridensis, P. radiata and P. brevispora were selected for their ligninolytic enzymes viz., lignin peroxidase, manganese peroxidase and laccase. Cell free enzyme extracts (as such and concentrated) obtained from these fungi were tested for their ability to decolourise reactive red 28 (Congo red), an industrial dye. The use of cell free enzyme extracts helped to overcome the problem of adsorption of dye to mycelia. Laccase production was best expressed in P. brevispora. Increase in decolourisation percentage by concentrated culture extract was comparable to increase in enzyme activity. P. floridensis proved to be a better dye decolouriser in comparison to Pha. chrysosporium, thus showing its potential for biocleaning of industrial wastes and wastewaters.

In this review, the present knowledge on the occurrence of cellulases, with a special emphasis on the presence of carbohydrate-binding modules (CBMs) in various fungal strains, has been summarized. The importance of efficient fungal cellulases is growing due to their potential uses in biorefinery processes where lignocellulosic biomasses are converted to platform sugars and further to biofuels and chemicals. Most secreted cellulases studied in detail have a bimodular structure containing an active core domain attached to a CBM. CBMs are traditionally been considered as essential parts in cellulases, especially in cellobiohydrolases. However, presently available genome data indicate that many cellulases lack the binding domains in cellulose-degrading organisms. Recent data also demonstrate that CBMs are not necessary for the action of cellulases and they solely increase the concentration of enzymes on the substrate surfaces. On the other hand, in practical industrial processes where high substrate concentrations with low amounts of water are employed, the enzymes have been shown to act equally efficiently with and without CBM. Furthermore, available kinetic data show that enzymes without CBMs can desorb more readily from the often lignaceous substrates, that is, they are not stuck on the substrates and are thus available for new actions. In this review, the available data on the natural habitats of different wood-degrading organisms (with emphasis on the amount of water present during wood degradation) and occurrence of cellulose-binding domains in their genome have been assessed in order to identify evolutionary advantages for the development of CBM-less cellulases in nature., (© 2014 Elsevier Inc. All rights reserved.)

Soil fungi are key players in the degradation of recalcitrant organic matter in terrestrial ecosystems. To examine the organisms and genes responsible for complex organic matter degradation in soil, we tracked changes in fungal community composition and expressed genes in soil adjacent to mesh bags containing maize leaves undergoing decomposition. Using high-throughput sequencing approaches, changes in fungal community composition were determined by targeting 18S rRNA gene sequences, whereas community gene expression was examined via a metatranscriptomic approach. The majority of the 93 000 partial 18S rRNA gene sequences generated, were affiliated with the Ascomycota and Basidiomycota. Fungal diversity was at least 224 operational taxonomic units at the 97% similarity cutoff level. During litter degradation, the relative proportion of Basidiomycota increased, with a decrease in Ascomycota : Basidiomycota ratios over time. The most commonly detected decomposition-associated fungi included Agaricomycetes and Tremellales as well as unclassified Mucoromycotina. The majority of protein families found in the metatranscriptomic data were affiliated to fungal groups described to degrade plant-derived cellulose, such as Mucoraceae, Chaetomiaceae, Sordariaceae, Sebacinaceae, Tremellaceae, Psathyrellaceae and Schizophyllaceae. The combination of high-throughput rRNA gene-based and metatranscriptomic approaches provided perspectives into the organisms and genes involved in complex organic matter in soil., (© 2013 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.)

Liquid chromatography negative ion electrospray ionisation tandem mass spectrometry has been used for characterisation of naturally occurring prenylated fungal metabolites and synthetic derivatives. The fragmentation studies allow an elucidation of the decomposition pathways for these compounds. It could be shown, that the prenyl side chain is degraded by successive radical losses of C(5) units. Both the benzoquinones and the phenolic derivatives display significant key ions comprising the aromatic ring. In some cases, the formation of significant oxygen-free key ions could be evidenced by high-resolution MS/MS measurements. Furthermore, the different types of basic skeletons, benzoquinones and phenol type as well as cyclic prenylated compounds, can be differentiated by their MS/MS behaviour. Figure Fruiting bodies of Suillus bovinus, the structure of boviquinone-4 and its negative ion MS2 spectrum.

Bisphenol A (BPA) is an endocrine disruptor compound (EDC) of xenobiotic origin occurring in natural waters and wastewaters, especially in the most industrialized and urbanized areas. Recent investigations report the use of ligninolytic fungi for the removal of aromatic contaminants, including some EDCs, from different matrices. Humic acids (HA) are widely spread in all natural systems and their presence is ascertained to interfere with microbial growth and activity. The objective of this study was to assess the capacity of three ligninolytic fungi, Trametes versicolor, Stereum hirsutum and Pleurotus ostreatus, to remove BPA at the concentration of 4.6 mg L(-1) from water. Fungal growth on potato dextrose agar (PDA), in the absence and in the presence of a leonardite HA or a green compost HA, was evaluated during the biodecontamination process. The methodological approach adopted in this study excluded the presence of the mycelium in the contaminated water. Results obtained evidenced a relevant removal of BPA by any fungus when PDA only was used as growing medium. The addition of leonardite HA and compost HA stimulated the mycelial growth of any fungus, especially T. versicolor, and significantly enhanced the removal of the contaminant from water by, respectively, T. versicolor only and T. versicolor and S. hirsutum., (Copyright © 2012 Elsevier Inc. All rights reserved.)

We tested the decay abilities of 28 isolates from 28 lignicolous fungal species (Basidiomycota, Ascomycota and Zygomycota) with the pure culture test. We used beech wood powder in varying moisture conditions and decay stages (nondecayed, intermediately decayed and well decayed) as substrates. The weight loss in wood powder was -0.2-17.8%. Five isolates of Basidiomycota (Bjerkandera adusta, Mycena haematopus, Omphalotus guepiniformis, Trametes hirsuta, Trametes versicolor) caused high weight losses in nondecayed wood. We detected significant effects of decay stage on weight loss in wood in most isolates tested, whereas moisture content rarely had an effect on weight loss. Among Basidiomycota and Xylariaceae in Ascomycota weight loss was greater for nondecayed wood than for intermediately and well decayed wood. In contrast four isolates in Ascomycota (Scytalidium lignicola, Trichoderma hamatum, T. harzianum, T. koningii) caused substantial weight loss in intermediately and well decayed wood, although they rarely caused weight loss in nondecayed wood. Zygomycota caused low weight loss in wood. Wood decay stages also affected decomposition of wood chemical components. Acid-unhydrolyzable residue (AUR) decomposition was reduced, whereas holocellulose decomposition was stimulated by some strains of Basidiomycota and Ascomycota in well decayed wood. T. harzianum in particular caused significant weight loss of holocellulose in well decayed wood, although this fungus caused negligible weight loss of both AUR and holocellulose in nondecayed wood. We discuss these changes in the decay patterns of AUR and holocellulose with varying wood decay stages in relation to the role of fungal decomposition of woody debris in forests.

The diversity and antimicrobial activities of 80 fungi isolated from Haliclona simulans were assessed using different fungal media containing either agar or gellum gum. In total, 19 different genotypes were detected. These fungal isolates could be classified as members of the Agaricomycotina, Mucoromycotina, Saccharomycotina, and Pezizomycotina, although the majority of the isolates were associated with the latter class. Some of these fungal isolates showed antimicrobial inhibition of Escherichia coli, Bacillus sp., Staphylococcus aureus, and Candida glabrata. Fungal 18S rRNA gene sequences belonging to Eurotiales, Calosphaeriales, and Chaetothyriales were amplified from DNA and RNA extracted from this marine sponge. This study indicates that in contrast to the low diversity of fungi detected by polymerase chain reaction (PCR) and reverse transcription (RT)-PCR amplification from extracts of this marine sponge, a much higher diversity of fungi could be cultured. The data suggests that some fungi live in symbiosis with H. simulans, whereas other fungi may have been ingested from the surrounding seawater.

Bioautography of extracts of the fruiting bodies of the basidiomycete Gomphus floccosus (Schw.) Singer indicated the presence of fungitoxic compounds in the ethyl acetate fraction against the plant pathogens Colletotrichum fragariae, Colletotrichum gloeosporioides, and Colletotrichum acutatum. Bioassay-guided fractionation of this fraction resulted in the isolation of the bioactive fatty acids (9 S,10 E,12 Z)-9-hydroxy-10,12-octadecadienoic acid (1), (9 E,11 Z)-13-oxo-9,11-octadecadienoic acid (2), and (10 E,12 E)-9-oxo-10,12-octadecadienoic acid (3). These three oxylipins were further evaluated for activity against a greater range of fungal plant pathogens (C. fragariae, C. gloeosporioides, C. acutatum, Botrytis cinerea, Fusarium oxysporum, Phomopsis obscurans, and Phomopsis viticola) in in vitro dose-response studies. Phomopis species were the most sensitive fungi to these compounds. At 120 h of treatment, the IC50 values for compounds 1, 2, and 3 for P. obscurans were 1.0, 4.5, and 23 microM, respectively, as compared to 1.1 microM for the captan positive control.

The present paper reports the presence of bacteria and yeasts tightly associated with spores of an isolate of Glomus mosseae. Healthy spores were surface disinfected by combining chloramine-T 5%, Tween-40, and cephalexin 2.5 g L(-1) (CTCf). Macerates of these spores were incubated on agar media, microorganisms were isolated, and two yeasts were characterized (EndoGm1, EndoGm11). Both yeasts were able to solubilize low-soluble P sources (Ca and Fe phosphates) and accumulate polyphosphates (polyPs). Sequence analysis of 18S ribosomal deoxyribonucleic acid showed that the yeasts belong to the genera Rhodotorula or Rhodosporidium (EndoGm1) and Cryptococcus (EndoGm11). Results from inoculation experiments showed an effect of the spore-associated yeasts on the root growth of rice, suggesting potential tripartite interactions with mycorrhizal fungi and plants.

Fungi, in particular, basidiomycetous fungi, are very successful in colonizing microconfined mazelike networks (for example, soil, wood, leaf litter, plant and animal tissues), a fact suggesting that they may be efficient solving agents of geometrical problems. We therefore evaluated the growth behavior and optimality of fungal space-searching algorithms in microfluidic mazes and networks. First, we found that fungal growth behavior was indeed strongly modulated by the geometry of microconfinement. Second, the fungus used a complex growth and space-searching strategy comprising two algorithmic subsets: 1) long-range directional memory of individual hyphae and 2) inducement of branching by physical obstruction. Third, stochastic simulations using experimentally measured parameters showed that this strategy maximizes both survival and biomass homogeneity in microconfined networks and produces optimal results only when both algorithms are synergistically used. This study suggests that even simple microorganisms have developed adequate strategies to solve nontrivial geometrical problems.

The effect of litter type and incubation temperature on the ability of fungi to decompose leaf litter of subalpine trees was examined by a pure-culture test. Mass loss of Abies needle and Betula leaf litter and utilization patterns of lignin and carbohydrates were investigated under two temperature conditions (20 C and 10 C) and compared for 29 species in basidiomycetes, ascomycetes and zygomycetes. The decomposing ability was generally higher in basidiomycetes than in ascomycetes and zygomycetes. Mass loss (% original mass) of litter was higher in Betula than in Abies and higher at 20 C than at 10 C. The 29 fungi were divided into lignocellulose decomposers, cellulose decomposers and sugar fungi based on their substrate utilization in Abies and Betula litter. Mass loss of lignin and carbohydrates by lignocellulose and cellulose decomposers was higher in Betula than in Abies. Mass loss of carbohydrates was higher at 20 C than at 10 C, but the temperature did not influence mass loss of lignin, indicating lignin decomposition by fungi was less sensitive to temperature than carbohydrate decomposition. Lignin/carbohydrate loss ratio (L/C) of Collybia spp. that caused selective delignification was lower at 20 C than at 10 C. These results indicate that the decomposability of litter, lignin and carbohydrate was different between Abies and Betula and that temperature affected not only the rate at which fungi decompose litter but also the ability of fungi to use lignin and carbohydrates.

Several asco-, basidio-, and zygomycetes isolated from an agricultural field were shown to be able to hydroxylate the phenylurea herbicide isoproturon [N-(4-isopropylphenyl)-N',N'-dimethylurea] to N-(4-(2-hydroxy-1-methylethyl)phenyl)-N',N'-dimethylurea and N-(4-(1-hydroxy-1-methylethyl)phenyl)-N',N'-dimethylurea. Bacterial metabolism of isoproturon has previously been shown to proceed by an initial demethylation to N-(4-isopropylphenyl)-N'-methylurea. In soils, however, hydroxylated metabolites have also been detected. In this study we identified fungi as organisms that potentially play a major role in the formation of these hydroxylated metabolites in soils treated with isoproturon. Isolates of Mortierella sp. strain Gr4, Phoma cf. eupyrena Gr61, and Alternaria sp. strain Gr174 hydroxylated isoproturon at the first position of the isopropyl side chain, yielding N-(4-(2-hydroxy-1-methylethyl)phenyl)-N',N'-dimethylurea, while Mucor sp. strain Gr22 hydroxylated the molecule at the second position, yielding N-(4-(1-hydroxy-1-methylethyl)phenyl)-N',N'-dimethylurea. Hydroxylation was the dominant mode of isoproturon transformation in these fungi, although some cultures also produced traces of the N-demethylated metabolite N-(4-isopropylphenyl)-N'-methylurea. A basidiomycete isolate produced a mixture of the two hydroxylated and N-demethylated metabolites at low concentrations. Clonostachys sp. strain Gr141 and putative Tetracladium sp. strain Gr57 did not hydroxylate isoproturon but N demethylated the compound to a minor extent. Mortierella sp. strain Gr4 also produced N-(4-(2-hydroxy-1-methylethyl)phenyl)-N'-methylurea, which is the product resulting from combined N demethylation and hydroxylation.

We tested whether fungal communities are impacted by nitrogen deposition or increased precipitation by PCR-amplifying partial fungal rRNA genes from 24 soil and 24 root samples from a nitrogen enrichment and irrigation experiment in a tallgrass prairie at Konza Prairie Biological Station in northeastern Kansas, U.S.A. Obtained fungal sequences represented great fungal diversity that was distributed mainly in ascomycetes and basiodiomycetes; only a few zygomycetes and glomeromycetes were detected. Conservative extrapolated estimates of the fungal species richness suggest that the true richness may be at least twice as high as observed. The effects of nitrogen enrichment or irrigation on fungal community composition, diversity or clone richness could not be unambiguously assessed because of the overwhelming diversity. However, soil communities differed from root communities in diversity, richness and composition. The compositional differences were largely attributable to an abundant, soil-inhabiting group placed as a well-supported sister group to other ascomycetes. This group likely represents a novel group of fungi. We conclude that the great fungal richness in this ecosystem precluded a reliable assessment of anthropogenic impacts on soil or rhizosphere communities using the applied sampling scheme, and that detection of novel fungi in soil may be more a rule than an exception.

It has been revealed that the use of synthetic food preservatives has variety of various side effects and hence search of safe and effective natural preservative has become a need. With the afore said objective the present study to screen the possibility of using sesquiterpenoid extract of local folk mushroom Phellinus fastuosus as food preservative was undertaken. Microbial growth inhibition by sesquiterpenoid extract of Phellinus was evaluated in the media with natural ingredient such as milk agar (MA), tomato juice agar (TJA), wheat flour agar (WFA) and pineapple juice agar (PAJA) with the composition with Phellinus extract, sodium benzoate and combinations. Three strains of bacteria and one strain of fungus were used astest organisms. The sesquiterpenoid extract of Phellinus at 0.02% concentration significantly inhibited the growth of all test organisms on natural media and the results were comparable with sodium benzoate. Similarly combination of Phellinus extract and sodium benzoate completely inhibited the growth of all microorganisms in all media, suggesting the possibility of using the Phellinus extract as food preservative.

The biodegradation of Grey Lanaset G, which consists of a mixture of metal complexed dye, was studied. Experiments were carried out in a bioreactor with retained pellets of the fungus Trametes versicolor that was operated under conditions of laccase production. Although decolorization was highly efficient (90%), no direct relationship to extracellular enzyme was apparent. Moreover, the extracellular enzyme was found to be unable to degrade the dye in vitro. The process involves several steps. Thus, the initial adsorption of the dye and its transfer into cells is followed by breaking of the metal complex bond in the cells release of the components. The metal (Cr and Co) contents of the biomass and treated solutions, and their closer relationship to intracellular enzyme and degradation of the dye, confirm the initial hypothesis.

Twelve selected Cyathus species were tested for their abilities to produce antimicrobial metabolites. Most of them were found to produce secondary exo-metabolites that could induce morphological abnormalities of rice pathogenic fungi Pyricularia oryzae. Some extracts from the cultivated liquid obviously inhibited human pathogenic fungi Aspergillus fumigatus, Candida albicans and Cryptococcus neoformans. Activities against six human pathogenic bacteria were also obtained from some of these extracts.

Resistance of pathogenic bacteria to antibiotics leads scientists to discover new antibacterial drugs. Ninety samples of wood-colonizing fungi were cultivated on agar plates, and their extracts tested for antibacterial activity using the Vibrio fischeri bioluminescence test. Two fungi species, Serpula lacrymans and Nectria vilior, were found to be a potential new source of thermostable antibiotics. Vibrio fischeri bioluminescence test was found to be a useful method for antibacterial activity screening from the samples of natural origin., (Copyright 2004 WILEY-VCH Verlag GmbH & Co.)

Fungi, like all free-living organisms, are in competition for limiting nutrients. In accumulating iron, fungi are faced also with a trace metal whose aqueous and redox chemistry make it both relatively bio-unavailable and strongly cytotoxic. Successful adaptation to this environmental context has provided fungi with an iron uptake strategy that has three features: it relies on redox cycling to enhance iron bio-availability and reduce iron cytotoxicity; it includes both high- and low-affinity pathways that are mechanistically distinct; and it is autoregulating so as to maintain intracellular iron homeostasis. Using Saccharomyces cerevisiae as a paradigm, this review summarizes current knowledge about the four pathways by which this yeast accumulates iron. These four pathways include: siderophore iron accumulation; high affinity iron uptake via an iron permease; and two lower affinity uptake pathways through relatively non-specific divalent metal ion transporters. All of these four pathways are directly or indirectly dependent on the activity of metalloreductase activity expressed extracellularly on the plasma membrane. A variety of experimental and genomics data indicate that this resourcefulness is shared by many, if not most, fungi. On the other hand, while the autoregulation of iron metabolism in Baker's yeast is well-understood, little is known about the apparent homeostatic mechanisms in these other yeasts and fungi. The integration of these multiple uptake mechanisms and their regulation into over-all iron homeostasis in yeast concludes this brief review.

The sources of ligninocellulose that occur in various forms in nature are so vast that they can only be compared to those of water. The results of several, more recent experiments showed that laccase probably possesses the big ability for "lignin-barrier" breakdown of ligninocellulose. The degradation of this compound is currently understood as an enzymatic process mediated by small molecules, therefore, this review will focus on the role of these mediators and radicals working in concert with enzymes. The fungi having a versatile machinery of enzymes are able to attack directly the "lignin-barrier" or can use a multienzyme system including "feed-back" type enzymes allowing for simultaneous transformation of lignin and carbohydrate compounds.

In this study, seven fungal strains, representing different phylogenetic groups within the Dikaryomycota, were tested for the presence of gamma-linolenic acid [18:3(omega 6)], when grown in synthetic liquid media devoid of fatty acids, on a series of 40 different carbon sources. The fungal strains represented the species Dipodascopsis uninucleata, Eurotium rubrum, Galactomyces geotrichum, Neurospora crassa, Saccharomyces cerevisiae, Spongipellis unicolor and Talaromyces flavus. Cultures were periodically harvested during growth and the fatty acids in the total lipids analysed as methyl esters, using gas chromatography and mass spectrometry. It was found that 18:3(omega 6) is present in E. rubrum CBS 350.65, S. unicolor CBS 117.16 and in T. flavus CBS 310.38NT, when these strains were grown on certain carbon sources. No correlation between the growth phase of the organism and the presence of 18:3(omega 6) could be detected. In order to confirm the production of 18:3(omega 6), the lipid metabolism of two unrelated dikaryomycotan fungi (S. unicolor CBS 117.16 and E. rubrum CBS 350.65) grown on two different carbon sources each, was examined. Cultures of E. rubrum CBS 350.65 were grown on glucose and sorbose and cultures of S. unicolor CBS 117.16 on glucose and sucrose in synthetic liquid media with a C:N ratio of 50:1 (w/w). The total lipids of these cultures were fractionated and the fatty acids in the fractions analysed as methyl esters, using gas chromatography and mass spectrometry. The lipid metabolism of both E. rubrum CBS 350.65 and S. unicolor CBS 117.16 differed on the two carbon sources used. The ab initio production of 18:3(omega 6) by E. rubrum CBS 350.65 in synthetic liquid media was confirmed. In contrast, the ab initio production of 18:3(omega 6) by S. unicolor CBS 117.16 in synthetic liquid media could not be confirmed.

Within a screening program, 91 fungal strains belonging to 32 genera of different ecological and taxonomic groups (wood- and litter-decaying basidiomycetes, saprophytic micromycetes) were tested for their ability to metabolize and mineralize 2,4,6-trinitrotoluene (TNT). All these strains metabolized TNT rapidly by forming monoaminodinitrotoluenes (AmDNT). Micromycetes produced higher amounts of AmDNT than did wood- and litter-decaying basidiomycetes. A significant mineralization of [14C]TNT was only observed for certain wood- and litter-decaying basidiomycetes. The most active strains, Clitocybula dusenii TMb12 and Stropharia rugosa-annulata DSM11372 mineralized 42% and 36% respectively of the initial added [14C]TNT (100 microM corresponding to 4.75 microCi/l) to 14CO2 within 64 days. Micromycetes (deuteromycetes, ascomycetes, zygomycetes) proved to be unable to mineralize [14C]TNT significantly.

The biodegradation of nylon by lignin-degrading fungi was investigated. The fungus IZU-154 significantly degraded nylon-66 membrane under ligninolytic conditions. Nuclear magnetic resonance analysis showed that four end groups, CHO, NHCHO, CH3, and CONH2, were formed in the biodegraded nylon-66 membranes, suggesting that nylon-66 was degraded oxidatively.

The veterinary fluoroquinolone enrofloxacin was degraded in vitro by four species of wood-rotting fungi growing on wetted wheat straw containing carbonyl-14C-labeled drug. A maximum 14CO2 production of 17% per week was observed with the brown rot fungus Gloeophyllum striatum, resulting in up to 53% after 8 weeks. However, rates reached at most 0.2 and 0.9% per week, if enrofloxacin was preadsorbed to native or gamma ray-sterilized soil, respectively.

A bleachery effluent from a sulfite process pulp mill, which was extracted with alkali and treated with oxygen and hydrogen peroxide (EOP), was treated with two fungi, Trametes versicolor and Stagonospora gigaspora. Trametes versicolor did not cause any depolymerization or degradation of effluent lignins but increased the amount of chromophores, whereas S. gigaspora depolymerized the EOP lignins and caused a substantial reduction in aromatic compounds. For both fungal treatments, CuO oxidation caused a decrease in the yield of the aldehydes within the vanillyl and p-hydroxy phenol families, which was faster than the rates of decrease in the yields of the corresponding acids and ketones. However, only S. gigaspora caused changes in the pattern of the 11 characteristic lignin phenols produced by CuO oxidation, reflecting a preferential metabolism of some phenolic precursors. This fungus decreased the yield of total vanillyl phenols (V), which contributed the bulk of the 11 lignin oxidation products, from 93% initially to 59%. As a consequence, coumaryl (C), syringyl (S), and p-hydroxy phenols (P) became relatively enriched to 1.2, 6.5, and 33%, respectively. The stability of EOP-lignin constituent subunits is S > P > C > V. The two fungi differed significantly in their level of enzyme activities. In effluent-free medium, the ratio of laccase to peroxidase was higher for T. versicolor than for S. gigaspora. The presence of EOP-lignins significantly increased this ratio. No lignin peroxidase was detected but manganese peroxidase and laccase were detected during degradation activities.

Streptomyces cinnamonensis produces a new substance named AIB (for anti-isobutyrate) factor which, on a solid medium, efficiently counteracts toxic concentrations not only of isobutyrate but also of other salts of short-chain monocarboxylic acids. In the present study we demonstrate that the AIB factor activity is widely spread because this effect was positively detected in 25 of 31 randomly chosen microorganisms (streptomycetes, ascomycetes, zygomycetes and basidiomycetes). The AIB factor produced by the tested microorganisms on an agar media allows for germination, growth, and sporulation of the testing Streptomyces coelicolor on an agar medium containing 20 mmol/L acetate, propionate, butyrate, isobutyrate, valerate, isovalerate, and 2-methylbutyrate. The activity of the AIB factor from different sources towards these substances differs.

We found that in the presence of host plant cells or some antagonistic fungi, the highly forest-pathogenic basidiomycete Armillaria ostoyae is strongly stimulated to produce a series of toxic secondary metabolites which are capable of inhibiting the growth of the antagonist or of killing the plant cells still before cell contact. The chemical structures of the metabolites have been identified, of which two of them are new compounds. The time dependence and sites of synthesis in the mycelium have been determined in order to lay the foundation for future studies concerning the induction mechanism for the synthesis of the toxins.

A number of microorganisms were screened for their ability to metabolize phencyclidine. Two microorganisms, Beauveria sulfurescens and Cunninghamella echinulata, produced hydroxylated metabolites, which were identified as 1-(1-phenylcyclohexyl)-4-hydroxypiperidine and 4-phenyl-4-piperidinocyclohexanol by high-pressure liquid chromatographic analysis.

A systematic study on autolysis of the cell walls of fungi has been made on Neurospora crassa, Botrytis cinerea, Polystictus versicolor, Aspergillus nidulans, Schizophyllum commune, Aspergillus niger, and Mucor mucedo. During autolysis each fungus produces the necessary lytic enzymes for its autodegradation. From autolyzed cultures of each fungus enzymatic precipitates were obtained. The degree of lysis of the cell walls, obtained from non-autolyzed mycelia, was studied by incubating these cell walls with and without a supply of their own lytic enzymes. The degree of lysis increased with the incubation time and generally was higher with a supply of lytic enzymes. Cell walls from mycelia of different ages were obtained. A higher degree of lysis was always found, in young cell walls than in older cell walls, when exogenous lytic enzymes were present. In all the fungi studied, there is lysis of the cell walls during autolysis. This is confirmed by the change of the cell wall structure as well as by the degree of lysis reached by the cell wall and the release of substances, principally glucose and N-acetylglucosamine in the medium.

An unidentified basidiomycete was found capable of parasitizing 37 of 50 isolates of fungi tested as hosts. All phytopathogenic fungi tested, as well as most of the saprophytic fungi, were susceptible to this mycoparasite. In some cases, reproductive structures as well as hyphae were infected. High glucose-yeast extract ratios in the test medium favored parasitism. The mycoparasite was able to utilize 14 of 27 compounds tested as carbon sources.