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At least 19 recordsLinked to original sources
PubMed2000

Ubiquinone systems in fungi. V. Distribution and taxonomic implications of ubiquinones in Eurotiales, Onygenales and the related plectomycete genera, except for Aspergillus, Paecilomyces, Penicillium, and their related teleomorphs.

The ubiquinone (coenzyme Q) systems were determined for 176 teleomorphic isolates, 14 anamorphic isolates, and three samples of fruit-bodies of Dendrosphaera eberhardtii, which belonged to Eurotiales, Onygenales, and related taxa. In Eurotiales, Ascosphaera had Q-9, whereas Bettsia had Q-10. All isolates of Monascaceae had the Q-10 system, whereas those of four genera of Pseudeurotiaceae had the Q-10(H2) system. The Q-10(H2) system was found in genera of Trichocomaceae, except for Aspergillus, Penicillium, Paecilomyces, and their related taxa. However, Thermoascus had the Q-9 system. In Onygenales, members of Arthrodermataceae had Q-9, and those of Gymnoascaceae had Q-10(H2). Isolates of Myxotrichaceae were characterized by Q-10(H2) with few exceptions, which had Q-10. The quinones of Onygenaceae belonged to complex systems, i.e., Q-9, 0-10 and 0-10(H2), and a combination of two systems. Families Onygenaceae and Trichocomaceae are likely a phylogenetic heterogeneity. Ubiquinone analysis provides a very useful criterion of great promise for classifying eurotialean taxa and also for identifying their isolates.

Ascomycota↗
PubMed2006

The mycorrhizal status of Pseudotulostoma volvata (Elaphomycetaceae, Eurotiales, Ascomycota).

Pseudotulostoma volvata (O. K. Mill. and T. W. Henkel) is a morphologically unusual member of the otherwise hypogeous Elaphomycetaceae due to its epigeous habit and exposed gleba borne on an elevated stalk at maturity. Field observations in Guyana indicated that P. volvata was restricted to rain forests dominated by ectomycorrhizal (EM) Dicymbe corymbosa (Caesalpiniaceae), suggesting an EM nutritional mode for the fungus. In this paper, we confirm the EM status of P. volvata with a combination of morphological, molecular, and mycosociological data. The EM status for P. volvata corroborates its placement in the ectotrophic Elaphomycetaceae.

Ecosystem↗
PubMed1995

Molecular phylogeny of the fungi of the Iceman's grass clothing.

To investigate the origin of the fungal hyphae that cover the grass clothing (cloak, boots) found near the neolithic mummy known as the Tyrolean Iceman, two radiocarbon-dated samples of grass were submitted to DNA extraction. The DNA was then PCR amplified using, respectively, primers specific for the region containing the internal transcribed spacers and the 5.8s rDNA (ITS), and primers specific for an approximately 600-bp long fragment of the nuclear small-subunit ribosomal DNA (SSU rDNA) repeat units of eukaryotes. The amplification products were cloned and sequenced. Sequence analysis of 20 individual ITS clones and of ten SSU rDNA clones indicated that three types of fungal DNA can be extracted from the grass. Phylogenetic analyses, using 5.8s and SSU rDNA fungal reference sequences from EMBL and GenBank databases, suggest that the DNAs come, respectively, from a psychrophilic basidiomycetous yeast, phylogenetically close to Leucosporidium scottii, and from two ascomycetes, one of which is possibly related to the Eurotiales.

Ascomycota↗
PubMed2005

Characterisation of Aspergillus niger prolyl aminopeptidase.

We have cloned a gene (papA) that encodes a prolyl aminopeptidase from Aspergillus niger. Homologous genes are present in the genomes of the Eurotiales A. nidulans, A. fumigatus and Talaromyces emersonii, but the gene is not present in the genome of the yeast Saccharomyces cerevisiae. Cell extracts of strains overexpressing the gene under the control of its own promoter showed a fourfold to sixfold increase in prolyl aminopeptidase activity, but no change in phenylalanine or leucine aminopeptidase activity. The overexpressed enzyme was subsequently purified and characterised. The enzyme specifically removes N-terminal proline and hydroxyproline residues from peptides. It is the first enzyme of its kind from a eukaryotic organism that has been characterised.

Amino Acid Sequence↗
PubMed2005

Phylogenetic relationships of Lecanoromycetes (Ascomycota) as revealed by analyses of mtSSU and nLSU rDNA sequence data.

The phylogeny of Lecanoromycetes (Ascomycota, Fungi) is investigated utilizing parsimony and Bayesian Markov Chain Monte Carlo analyses, of combined nLSU rDNA and mtSSU rDNA sequence datasets. The results suggest that Acarosporaceae, Candelariaceae, Phlyctis and Pycnora are not members of the monophyletic Lecanorales, and that Timdalia and Pleopsidium are members of a monophyletic Acarosporaceae. Pycnora, Candelariaceae and Acarosporaceae form a monophyletic group. Umbilicariaceae, Hypocenomyce scalaris, H. friesii, Ophioparmaceae, Boreoplaca, Elixia and Fuscidea form either a basal paraphyletic assemblage in Lecanoromycetes, or a monophyletic group which is the sister-group to Lecanorales and the rest of Lecanoromycetes (excluding Acarosporaceae). The Acarosporaceae forms a group with Pycnora and Candelariaceae, which may be outside the Lecanoromycetes. Chaetothyriales, Verrucariales, Eurotiales, Lichinales and Mycocaliciales form a monophyletic group, but with low support. We briefly discuss incongruence between datasets from different genetic markers, comparing the differences between the separate parsimony analyses, where the ILD test indicated a very significant incongruence. The phylogenetic significance of ascus-types that have influenced most recent Ascomycota classifications heavily is also discussed, and we finally point out risks with formalizing classifications too early.

Ascomycota↗
PubMed2000

Screening of basidiomycetes for antimicrobial activities.

As a part of a screening programme developed to evaluate the antimicrobial activity of basidiomycetes, 317 isolates representing 204 species collected in Spain were screened against a range of human clinical pathogens and laboratory controls. Extracts from 45% of the isolates, representing 109 species, showed antimicrobial activity. Antibacterial activity was more pronounced than antifungal activity. The proportion of extracts from basidiomycetes showing antimicrobial activity was similar to or above that obtained for representative orders of Ascomycetes, such as Pezizales and Xylariales, but lower than that produced by members of the orders Diaporthales, Eurotiales, Hypocreales, Leotiales and Sordariales. Suprageneric taxa (orders and families) did not show pronounced differences in their antimicrobial activities though such differences were observed at the genus level, suggesting that the ability to produce these bioactive compounds is not homogenously distributed amongst the basidiomycetes. Isolates from some species showed large differences in their ability to produce metabolites with antimicrobial activity, possibly reflecting genetic differences at the infraspecific level.

Anti-Bacterial Agents↗
PubMed1999

Developments in fungal taxonomy.

Fungal infections, especially those caused by opportunistic species, have become substantially more common in recent decades. Numerous species cause human infections, and several new human pathogens are discovered yearly. This situation has created an increasing interest in fungal taxonomy and has led to the development of new methods and approaches to fungal biosystematics which have promoted important practical advances in identification procedures. However, the significance of some data provided by the new approaches is still unclear, and results drawn from such studies may even increase nomenclatural confusion. Analyses of rRNA and rDNA sequences constitute an important complement of the morphological criteria needed to allow clinical fungi to be more easily identified and placed on a single phylogenetic tree. Most of the pathogenic fungi so far described belong to the kingdom Fungi; two belong to the kingdom Chromista. Within the Fungi, they are distributed in three phyla and in 15 orders (Pneumocystidales, Saccharomycetales, Dothideales, Sordariales, Onygenales, Eurotiales, Hypocreales, Ophiostomatales, Microascales, Tremellales, Poriales, Stereales, Agaricales, Schizophyllales, and Ustilaginales).

Ascomycota↗
PubMed1995

Analysis of genes coding for small-subunit rRNA sequences in studying phylogenetics of dematiaceous fungal pathogens.

Because of their ability to display yeast-like growth forms in various environmental conditions, dematiaceous (melanized) hyphomycetes of the form-genera Exophiala, Rhinocladiella, and Wangiella have been informally termed "black yeasts." Cladistic analysis of 1,050 bp of the genes coding for small-subunit rRNA (SSU rDNA) supported a close relationship among species of these black yeasts with other dematiaceous hyphomycetes in the form-genera Fonsecaea, Phialophora, and Ramichloridium. The conventional categories of these fungi based on asexual states are not supported by phylogenetic analysis of SSU rDNA sequences. Isolates exhibiting annellidic modes of blastic conidiogenesis (e.g., Exophiala spp.) were not monophyletic and were placed as sister taxa to isolates that produce phialides or sympodulae. The results indicated very close relationships between isolates of Wangiella dermatitidis and Exophiala mansonii and between Rhinocladiella aquaspersa and Exophiala jeanselmei. This clade of dematiaceous hyphomycetes was a sister group to a clade comprising members of two orders of cleistothecial ascomycetes, Eurotiales and Onygenales. The etiological agents of chromoblastomycosis were found to be a closely related group (clade), while the agents of phaeohyphomycosis displayed a broader distribution on the SSU rDNA tree.

Ascomycota↗
PubMed2006

The distribution and evolutionary history of the PRP8 intein.

BACKGROUND: We recently described a mini-intein in the PRP8 gene of a strain of the basidiomycete Cryptococcus neoformans, an important fungal pathogen of humans. This was the second described intein in the nuclear genome of any eukaryote; the first nuclear encoded intein was found in the VMA gene of several saccharomycete yeasts. The evolution of eukaryote inteins is not well understood. In this report we describe additional PRP8 inteins (bringing the total of these to over 20). We compare and contrast the phylogenetic distribution and evolutionary history of the PRP8 intein and the saccharomycete VMA intein, in order to derive a broader understanding of eukaryote intein evolution. It has been suggested that eukaryote inteins undergo horizontal transfer and the present analysis explores this proposal. RESULTS: In total, 22 PRP8 inteins have been detected in species from three different orders of euascomycetes, including Aspergillus nidulans and Aspergillus fumigatus (Eurotiales), Paracoccidiodes brasiliensis, Uncinocarpus reesii and Histoplasma capsulatum (Onygales) and Botrytis cinerea (Helotiales). These inteins are all at the same site in the PRP8 sequence as the original Cryptococcus neoformans intein. Some of the PRP8 inteins contain apparently intact homing endonuclease domains and are thus potentially mobile, while some lack the region corresponding to the homing endonuclease and are thus mini-inteins. In contrast, no mini-inteins have been reported in the VMA gene of yeast. There are several examples of pairs of closely related species where one species carries the PRP8 intein while the intein is absent from the other species. Bio-informatic and phylogenetic analyses suggest that many of the ascomycete PRP8 homing endonucleases are active. This contrasts with the VMA homing endonucleases, most of which are inactive. CONCLUSION: PRP8 inteins are widespread in the euascomycetes (Pezizomycota) and apparently their homing endonucleases are active. There is no evidence for horizontal transfer within the euascomycetes. This suggests that the intein is of ancient origin and has been vertically transmitted amongst the euascomycetes. It is possible that horizontal transfer has occurred between the euascomycetes and members of the basidiomycete genus Cryptococcus.

Amino Acid Sequence↗
PubMedDate not supplied

Phylogenetic origins of two cleistothecial fungi, Orbicula parietina and Lasiobolidium orbiculoides, within the operculate discomycetes.

Parsimony, maximum-likelihood and Bayesian analyses of SSU rDNA sequences of representative taxa of Pezizomycetes, Eurotiomycetes, Dothideomycetes, Leotiomycetes and Sordariomycetes, all strongly support the cleistothecial fungi Orbicula parietina and Lasiobolidium orbiculoides to be of pezizalean origin. Previous hypotheses of close affinities with cleistothecial or highly reduced fungi now placed in the Thelebolales, Eurotiales or Onygenales are rejected. Orbicula parietina and L. orbiculoides are deeply nested within Pyronemataceae (which subsumes the families Ascodesmidaceae, Glaziellaceae and Otideaceae). LSU rDNA sequences suggest that Orbicula is nested within the apothecia-forming genus Pseudombrophila (including Nannfeldtiella and Fimaria) and that L. orbiculoides is closely related. Ascodesmis and Lasiobolus, which have been suggested as closely related to Orbicula and Lasiobolidium, are identified as a sister lineage to the Pseudombrophila lineage. Cleistothecial forms that have lost the ascus operculum and ability to discharge spores actively have evolved at least once in the Pseudombrophila lineage. Some species of Pseudombrophila produce subglobular ascomata initials that are closed early in development and open only in the mid-mesohymenial phase. We hypothesize that, in the Pseudombrophila lineage, ascomata forms that never open are derived from ascomata that open late in development. The placement of O. parietina and L. orbiculoides within Pseudombrophila is supported by morphological characters, ecology and temperature optima for fruiting.

Ascomycota↗
PubMed2006

A complete enzymatic recovery of ferulic acid from corn residues with extracellular enzymes from Neosartorya spinosa NRRL185.

An economic ferulic acid recovery from biomass via biological methods is of interest for a number of reasons. Ferulic acid is a precursor to vanillin synthesis. It is also a known antioxidant with potential food and medical applications. Despite its universal presence in all plant cell wall material, the complex structure of the plant cell wall makes ferulic acid recovery from biomass a challenging bioprocess. Previously, without pretreatment, very low (3-13%) recovery of ferulic acid from corn residues was achieved. We report here the discovery of a filamentous fungus Neosartorya spinosa NRRL185 capable of producing a full complement of enzymes to release ferulic acid and the development of an enzymatic process for a complete recovery of ferulic acid from corn bran and corn fibers. A partial characterization of the extracellular proteome of the microbe revealed the presence of at least seven cellulases and hemicellulases activities, including multiple iso-forms of xylanase and ferulic acid esterase. The recovered ferulic acid was bio-converted to vanillin, demonstrating its potential application in natural vanillin synthesis. The enzymatic ferulic acid recovery accompanied a significant release of reducing sugars (76-100%), suggesting much broader applications of the enzymes and enzyme mixtures from this organism.

Benzaldehydes↗
PubMed2005

Fungal biosynthesis of non-ribosomal peptide antibiotics and alpha, alpha-dialkylated amino acid constituents.

Zervamicins (Zrv) IIA and IIB are membrane modifying peptide antibiotics of fungal origin, characterized by a sequence of 15 amino acid residues. The primary structure of Zrv-IIA contains five alpha-aminoisobutyric acid residues at positions 4, 7, 9, 12 and 14 of the linear peptide. The sequence of Zrv-IIB is similar, but contains a D-isovaline at position 4. When the free amino acid Aib was added to the peptone-glucose culture medium, the fungus Emericellopsis salmosynnemata produced Zrv-IIA as the major secondary metabolite, whereas addition of DL-Iva to the culture led to a high production of Zrv-IIB. This observation is rationalized by a lack of selectivity of the non-ribosomal peptide synthetase with respect to the thiolester activated amino acid substrates during step 12 of peptide synthesis. Analysis of the configuration of the Iva residue of Zrv-IIB showed a high enantiomeric purity of the D-enantiomer, indicating a high stereoselectivity of the peptide synthetase for this substrate.When the culture was supplemented with [(15)N]DL-Iva, the nitrogen isotope was not only found at the D-Iva residue, but surprisingly also at the Aib residues as well as at the proteinogenic residues of Zrv. The partial catabolism of exogenous [(15)N]DL-Iva is explained by the assumption of a decarboxylation-dependent transamination reaction, catalysed by 2,2-dimethylglycine decarboxylase. The same enzyme might also be involved in the reversed carboxylation reactions of acetone and 2-butanone, during the anabolic biosynthesis of Aib and Iva, respectively. Zrv might possibly act as a thermodynamic sink to shift these equilibrium reactions towards the reversed side.

Alkylation↗
PubMed2003

Cloning of a gene encoding thermostable cellobiohydrolase from Thermoascus aurantiacus and its expression in yeast.

A gene encoding a cellobiohydrolase (CBH) was isolated from Thermoascus aurantiacus IFO 9748 and designated as cbh1. The deduced amino acid sequence encoded by cbh1 showed high homology with the sequence of glycoside hydrolase family 7. To confirm the sequence of the gene encoding the CBH, the cloned gene was expressed in the yeast Saccharomyces cerevisiae, in which no cellulase activity was found, and the gene product was purified and subjected to enzymatic characterization. The recombinant enzyme was confirmed as a CBH by analysis of the reaction product and designated as CBHI. Recombinant CBHI retained more than 80% of its initial activity after 1 h of incubation at 65 degrees C and was stable in the pH range 3.0-9.0. The optimal temperature for enzyme activity was about 65 degrees C and the optimal pH was about 6.0. The recombinant enzyme was found to be highly glycosylated and this glycosylation was shown to contribute to the thermostability of the enzyme. CBHI expression was shown to be induced at higher temperature in T. aurantiacus.

Amino Acid Sequence↗
PubMed2006

Unusual hydrophobic linker region of beta-glucosidase (BGLII) from Thermoascus aurantiacus is required for hyper-activation by organic solvents.

A gene encoding a putative beta-glucosidase was isolated from Thermoascus aurantiacus IFO9748 and designated as bgl2. The recombinant enzyme showed beta-glucosidase activity when p-nitrophenyl-beta-glucose (pNP-Glc) was used as substrate. We also found that the enzyme activity was increased in the presence of organic solvents. An addition of 20 % (v/v) 1-octanol resulted in 54-fold higher activity of pNP-Glc hydrolysis, and transglycosylation activity was also found to be activated. The results of tryptophan fluorescence spectral analysis revealed the changes in the tertiary structure of the enzyme in the presence of 1-hexanol that may cause increased enzyme activity. BGLII has a distinctive hydrophobic linker region between N- and C-terminal domains. A chimeric enzyme in which the linker region was substituted by the corresponding region of another beta-glucosidase failed to be activated by organic solvents, suggesting that the hydrophobic linker region may act as a molecular switch in BGLII.

1-Octanol↗
PubMed2005

Microbial transformation of artemisinin to 5-hydroxyartemisinin by Eurotium amstelodami and Aspergillus niger.

Transformation of the anti-malarial drug artemisinin by the fungi Eurotium amstelodami and Aspergillus niger were investigated. Cultures were grown in sucrose/malt broth with artemisinin for 14 days and extracted with ethyl acetate. Extracts were characterized by liquid chromatography. Two metabolites from each fungal extract were isolated and identified using mass spectrometry and nuclear magnetic resonance. 5Beta-hydroxyartemisinin and 7beta-hydroxyartemisinin were isolated in 63 and 32% yields, respectively, from the extract of E. amstelodami, and 80 and 19%, respectively, from the extract of A. niger.

Anti-Infective Agents↗
PubMed2006

Phylogenetic analyses of penicillia based on partial calmodulin gene sequences.

Partial sequences (about 600 nucleotides) of the calmodulin gene were used for the phylogenetic studies on Eupenicillium, Talaromyces and Penicillium. This region is from the 3rd base of the codon for the 9th amino acid Gln to the 3rd base of the codon for the 122th amino acid Val, flanking parts of the 2nd and 5th exons with complete sequences of two exons and three introns. Seventy-six isolates of 56 taxa of penicillia were involved. The nucleotide sequences with and without introns were analyzed respectively using the neighbor-joining (NJ) and maximum parsimony (MP) methods. The cluster analysis on relative synonymous codon usage (RSCU) of each sequence was also carried out. The fact that species of penicillia belong to the two subfamilies of the Trichocomaceae proposed by Malloch based on traditional methods is supported by our molecular data, whereas, the development of asci and patterns of penicilli show little phylogenetic information. Nine groups in the lineage of Eupenicillium and two in that of Talaromyces were recognized in our studies. In addition to the teleomorph-holomorph-anamorph evolutionary model of penicillia suggested by LoBuglio et al., and Pitt, we proposed that a mutation bias of holomorphs/anamorphs with or without selection is another evolutionary path of these organisms.

Base Sequence↗
PubMed2006

Effect of intra and interspecific interaction on OTA production by A. section Nigri in grapes during dehydration.

The aim of this study was to assess the colonizing capability and OTA production of different populations of Aspergillus section Nigri spp. in grapes, as affected by the interactions with other fungi, during a simulated in vitro sun-drying. Mature white grapes were divided into two lots of healthy and artificially injured grapes and inoculated with A. section Nigri spp. (A. carbonarius OTA producer, A. niger aggregate OTA producer, A. niger aggregate OTA non-producer), Eurotium amstelodami and Penicillium janthinellum, in different combinations. The drying process was simulated adjusting water activity firstly at 0.98 a(w) and gradually decreasing it to 0.76 a(w) for a total of 20 days. Colonizing grape percentages were recorded after 5, 10, 15 and 20 days of dehydration and OTA content was measured after 5, 7, 10, 12, 15, 17 and 20 days. Colonization of grapes increased with time in all treatments. A. niger aggregate OTA-positive showed the highest colonization percentage, followed by A. carbonarius, and finally their mixed inoculum. When the two OTA-producing strains were combined, addition of any other microorganism increased the percentage of infection by A. section Nigri. A. carbonarius was the highest OTA producer in pure culture, followed by A. niger aggregate OTA-positive. In general, when competing fungi were added to A. carbonarius inoculum, the OTA content was reduced. E. amstelodami was the only competing fungus which increased OTA accumulation. The sun-drying process may be conducive to OTA accumulation in dried grapes. The complex fungal interactions which may take place during this process, may act as an additional control factor, given that the higher presence of A. niger aggregate OTA-negative inhibits OTA accumulation by OTA producing species.

Antibiosis↗