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Sample records for ascomycete podospora anserina

  1. Plant biomass degrading ability of the coprophilic ascomycete fungus Podospora anserina.

    PubMed

    Couturier, Marie; Tangthirasunun, Narumon; Ning, Xie; Brun, Sylvain; Gautier, Valérie; Bennati-Granier, Chloé; Silar, Philippe; Berrin, Jean-Guy

    2016-01-01

    The degradation of plant biomass is a major challenge towards the production of bio-based compounds and materials. As key lignocellulolytic enzyme producers, filamentous fungi represent a promising reservoir to tackle this challenge. Among them, the coprophilous ascomycete Podospora anserina has been used as a model organism to study various biological mechanisms because its genetics are well understood and controlled. In 2008, the sequencing of its genome revealed a great diversity of enzymes targeting plant carbohydrates and lignin. Since then, a large array of lignocellulose-acting enzymes has been characterized and genetic analyses have enabled the understanding of P. anserina metabolism and development on plant biomass. Overall, these research efforts shed light on P. anserina strategy to unlock recalcitrant lignocellulose deconstruction. PMID:27263000

  2. Heterologous production of cellobiose dehydrogenases from the basidiomycete Coprinopsis cinerea and the ascomycete Podospora anserina and their effect on saccharification of wheat straw.

    PubMed

    Turbe-Doan, Annick; Arfi, Yonathan; Record, Eric; Estrada-Alvarado, Isabel; Levasseur, Anthony

    2013-06-01

    Cellobiose dehydrogenases (CDHs) are extracellular glycosylated haemoflavoenzymes produced by many different wood-degrading and phytopathogenic fungi. Putative cellobiose dehydrogenase genes are recurrently discovered by genome sequencing projects in various phylogenetically distinct fungi. The genomes from the basidiomycete Coprinopsis cinerea and the ascomycete Podospora anserina were screened for candidate cdh genes, and one and three putative gene models were evidenced, respectively. Two putative cdh genes were selected and successfully expressed for the first time in Aspergillus niger. CDH activity was measured for both constructions (CDHcc and CDHpa), and both recombinant CDHs were purified to homogeneity and subsequently characterised. Kinetic constants were determined for several carbohydrates including β-1,4-linked di- and oligosaccharides. Optimal temperature and pH were 60 °C and 5 for CDHcc and 65-70 °C and 6 for CDHpa. Both CDHs showed a broad range of pH stability between 4 and 8. The effect of both CDHs on saccharification of micronized wheat straw by an industrial Trichoderma reesei secretome was determined. The addition of each CDH systematically decreased the release of total reducing sugars, but to different extents and according to the CDH concentration. Analytical methods were carried out to quantify the release of glucose, xylose and gluconic acid. An increase of glucose and xylose was measured at a low CDHcc concentration. At moderated and high CDHcc and CDHpa concentrations, glucose was severely reduced with a concomitant increase of gluconic acid. In conclusion, these results give new insights into the physical and chemical parameters and diversity of basidiomycetous and ascomycetous CDHs. These findings also demonstrated that CDH drastically influenced the saccharification on a natural substrate, and thus, CDH origin, concentration and potential enzymatic partners should be carefully considered in future artificial secretomes for

  3. Peroxisome dynamics during development of the fungus Podospora anserina.

    PubMed

    Takano-Rojas, Harumi; Zickler, Denise; Peraza-Reyes, Leonardo

    2016-01-01

    Peroxisomes are versatile and dynamic organelles that are required for the development of diverse eukaryotic organisms. We demonstrated previously that in the fungus Podospora anserina different peroxisomal functions are required at distinct stages of sexual development, including the initiation and progression of meiocyte (ascus) development and the differentiation and germination of sexual spores (ascospores). Peroxisome assembly during these processes relies on the differential activity of the protein machinery that drives the import of proteins into the organelle, indicating a complex developmental regulation of peroxisome formation and activity. Here we demonstrate that peroxisome dynamics is also highly regulated during development. We show that peroxisomes in P. anserina are highly dynamic and respond to metabolic and environmental cues by undergoing changes in size, morphology and number. In addition, peroxisomes of vegetative and sexual cell types are structurally different. During sexual development peroxisome number increases at two stages: at early ascus differentiation and during ascospore formation. These processes are accompanied by changes in peroxisome structure and distribution, which include a cell-polarized concentration of peroxisomes at the beginning of ascus development, as well as a morphological transition from predominantly spherical to elongated shapes at the end of the first meiotic division. Further, the mostly tubular peroxisomes present from second meiotic division to early ascospore formation again become rounded during ascospore differentiation. Ultimately the number of peroxisomes dramatically decreases upon ascospore maturation. Our results reveal a precise regulation of peroxisome dynamics during sexual development and suggest that peroxisome constitution and function during development is defined by the coordinated regulation of the proteins that control peroxisome assembly and dynamics. PMID:26908647

  4. Natural Variation of Heterokaryon Incompatibility Gene het-c in Podospora anserina Reveals Diversifying Selection

    PubMed Central

    Bastiaans, Eric; Debets, Alfons J.M.; Aanen, Duur K.; van Diepeningen, Anne D.; Saupe, Sven J.; Paoletti, Mathieu

    2014-01-01

    In filamentous fungi, allorecognition takes the form of heterokaryon incompatibility, a cell death reaction triggered when genetically distinct hyphae fuse. Heterokaryon incompatibility is controlled by specific loci termed het-loci. In this article, we analyzed the natural variation in one such fungal allorecognition determinant, the het-c heterokaryon incompatibility locus of the filamentous ascomycete Podospora anserina. The het-c locus determines an allogenic incompatibility reaction together with two unlinked loci termed het-d and het-e. Each het-c allele is incompatible with a specific subset of the het-d and het-e alleles. We analyzed variability at the het-c locus in a population of 110 individuals, and in additional isolates from various localities. We identified a total of 11 het-c alleles, which define 7 distinct incompatibility specificity classes in combination with the known het-d and het-e alleles. We found that the het-c allorecognition gene of P. anserina is under diversifying selection. We find a highly unequal allele distribution of het-c in the population, which contrasts with the more balanced distribution of functional groups of het-c based on their allorecognition function. One explanation for the observed het-c diversity in the population is its function in allorecognition. However, alleles that are most efficient in allorecognition are rare. An alternative and not exclusive explanation for the observed diversity is that het-c is involved in pathogen recognition. In Arabidopsis thaliana, a homolog of het-c is a pathogen effector target, supporting this hypothesis. We hypothesize that the het-c diversity in P. anserina results from both its functions in pathogen-defense, and allorecognition. PMID:24448643

  5. Natural variation of heterokaryon incompatibility gene het-c in Podospora anserina reveals diversifying selection.

    PubMed

    Bastiaans, Eric; Debets, Alfons J M; Aanen, Duur K; van Diepeningen, Anne D; Saupe, Sven J; Paoletti, Mathieu

    2014-04-01

    In filamentous fungi, allorecognition takes the form of heterokaryon incompatibility, a cell death reaction triggered when genetically distinct hyphae fuse. Heterokaryon incompatibility is controlled by specific loci termed het-loci. In this article, we analyzed the natural variation in one such fungal allorecognition determinant, the het-c heterokaryon incompatibility locus of the filamentous ascomycete Podospora anserina. The het-c locus determines an allogenic incompatibility reaction together with two unlinked loci termed het-d and het-e. Each het-c allele is incompatible with a specific subset of the het-d and het-e alleles. We analyzed variability at the het-c locus in a population of 110 individuals, and in additional isolates from various localities. We identified a total of 11 het-c alleles, which define 7 distinct incompatibility specificity classes in combination with the known het-d and het-e alleles. We found that the het-c allorecognition gene of P. anserina is under diversifying selection. We find a highly unequal allele distribution of het-c in the population, which contrasts with the more balanced distribution of functional groups of het-c based on their allorecognition function. One explanation for the observed het-c diversity in the population is its function in allorecognition. However, alleles that are most efficient in allorecognition are rare. An alternative and not exclusive explanation for the observed diversity is that het-c is involved in pathogen recognition. In Arabidopsis thaliana, a homolog of het-c is a pathogen effector target, supporting this hypothesis. We hypothesize that the het-c diversity in P. anserina results from both its functions in pathogen-defense, and allorecognition. PMID:24448643

  6. Insights into Exo- and Endoglucanase Activities of Family 6 Glycoside Hydrolases from Podospora anserina

    PubMed Central

    Poidevin, Laetitia; Feliu, Julia; Doan, Annick; Berrin, Jean-Guy; Bey, Mathieu; Coutinho, Pedro M.; Henrissat, Bernard; Record, Eric

    2013-01-01

    The ascomycete Podospora anserina is a coprophilous fungus that grows at late stages on droppings of herbivores. Its genome encodes a large diversity of carbohydrate-active enzymes. Among them, four genes encode glycoside hydrolases from family 6 (GH6), the members of which comprise putative endoglucanases and exoglucanases, some of them exerting important functions for biomass degradation in fungi. Therefore, this family was selected for functional analysis. Three of the enzymes, P. anserina Cel6A (PaCel6A), PaCel6B, and PaCel6C, were functionally expressed in the yeast Pichia pastoris. All three GH6 enzymes hydrolyzed crystalline and amorphous cellulose but were inactive on hydroxyethyl cellulose, mannan, galactomannan, xyloglucan, arabinoxylan, arabinan, xylan, and pectin. PaCel6A had a catalytic efficiency on cellotetraose comparable to that of Trichoderma reesei Cel6A (TrCel6A), but PaCel6B and PaCel6C were clearly less efficient. PaCel6A was the enzyme with the highest stability at 45°C, while PaCel6C was the least stable enzyme, losing more than 50% of its activity after incubation at temperatures above 30°C for 24 h. In contrast to TrCel6A, all three studied P. anserina GH6 cellulases were stable over a wide range of pHs and conserved high activity at pH values of up to 9. Each enzyme displayed a distinct substrate and product profile, highlighting different modes of action, with PaCel6A being the enzyme most similar to TrCel6A. PaCel6B was the only enzyme with higher specific activity on carboxymethylcellulose (CMC) than on Avicel and showed lower processivity than the others. Structural modeling predicts an open catalytic cleft, suggesting that PaCel6B is an endoglucanase. PMID:23645193

  7. Altered Mating-Type Identity in the Fungus Podospora Anserina Leads to Selfish Nuclei, Uniparental Progeny, and Haploid Meiosis

    PubMed Central

    Zickler, D.; Arnaise, S.; Coppin, E.; Debuchy, R.; Picard, M.

    1995-01-01

    In wild-type crosses of the filamentous ascomycete Podospora anserina, after fertilization, only nuclei of opposite mating type can form dikaryons that undergo karyogamy and meiosis, producing biparental progeny. To determine the role played by the mating type in these steps, the four mat genes were mutagenized in vitro and introduced into a strain deleted for its mat locus. Genetic and cytological analyses of these mutant strains, crossed to each other and to wild type, showed that mating-type information is required for recognition of nuclear identity during the early steps of sexual reproduction. In crosses with strains carrying a mating-type mutation, two unusual developmental patterns were observed: monokaryotic cells, resulting in haploid meiosis, and uniparental dikaryotic cells providing, after karyogamy and meiosis, a uniparental progeny. Altered mating-type identity leads to selfish behavior of the mutant nucleus: it migrates alone or paired, ignoring its wild-type partner in all mutant X wild-type crosses. This behavior is nucleus-autonomous because, in the same cytoplasm, the wild-type nuclei form only biparental dikaryons. In P. anserina, mat genes are thus required to ensure a biparental dikaryotic state but appear dispensable for later stages, such as meiosis and sporulation. PMID:7498731

  8. Cello-oligosaccharide oxidation reveals differences between two lytic polysaccharide monooxygenases (family GH61) from Podospora anserina.

    PubMed

    Bey, Mathieu; Zhou, Simeng; Poidevin, Laetitia; Henrissat, Bernard; Coutinho, Pedro M; Berrin, Jean-Guy; Sigoillot, Jean-Claude

    2013-01-01

    The genome of the coprophilic ascomycete Podospora anserina encodes 33 different genes encoding copper-dependent lytic polysaccharide monooxygenases (LPMOs) from glycoside hydrolase family 61 (GH61). In this study, two of these enzymes (P. anserina GH61A [PaGH61A] and PaGH61B), which both harbored a family 1 carbohydrate binding module, were successfully produced in Pichia pastoris. Synergistic cooperation between PaGH61A or PaGH61B with the cellobiose dehydrogenase (CDH) of Pycnoporus cinnabarinus on cellulose resulted in the formation of oxidized and nonoxidized cello-oligosaccharides. A striking difference between PaGH61A and PaGH61B was observed through the identification of the products, among which were doubly and triply oxidized cellodextrins, which were released only by the combination of PaGH61B with CDH. The mass spectrometry fragmentation patterns of these oxidized products could be consistent with oxidation at the C-6 position with a geminal diol group. The different properties of PaGH61A and PaGH61B and their effect on the interaction with CDH are discussed in regard to the proposed in vivo function of the CDH/GH61 enzyme system in oxidative cellulose hydrolysis. PMID:23124232

  9. Cello-Oligosaccharide Oxidation Reveals Differences between Two Lytic Polysaccharide Monooxygenases (Family GH61) from Podospora anserina

    PubMed Central

    Bey, Mathieu; Zhou, Simeng; Poidevin, Laetitia; Henrissat, Bernard; Coutinho, Pedro M.; Sigoillot, Jean-Claude

    2013-01-01

    The genome of the coprophilic ascomycete Podospora anserina encodes 33 different genes encoding copper-dependent lytic polysaccharide monooxygenases (LPMOs) from glycoside hydrolase family 61 (GH61). In this study, two of these enzymes (P. anserina GH61A [PaGH61A] and PaGH61B), which both harbored a family 1 carbohydrate binding module, were successfully produced in Pichia pastoris. Synergistic cooperation between PaGH61A or PaGH61B with the cellobiose dehydrogenase (CDH) of Pycnoporus cinnabarinus on cellulose resulted in the formation of oxidized and nonoxidized cello-oligosaccharides. A striking difference between PaGH61A and PaGH61B was observed through the identification of the products, among which were doubly and triply oxidized cellodextrins, which were released only by the combination of PaGH61B with CDH. The mass spectrometry fragmentation patterns of these oxidized products could be consistent with oxidation at the C-6 position with a geminal diol group. The different properties of PaGH61A and PaGH61B and their effect on the interaction with CDH are discussed in regard to the proposed in vivo function of the CDH/GH61 enzyme system in oxidative cellulose hydrolysis. PMID:23124232

  10. Comparative analyses of Podospora anserina secretomes reveal a large array of lignocellulose-active enzymes.

    PubMed

    Poidevin, Laetitia; Berrin, Jean-Guy; Bennati-Granier, Chloé; Levasseur, Anthony; Herpoël-Gimbert, Isabelle; Chevret, Didier; Coutinho, Pedro M; Henrissat, Bernard; Heiss-Blanquet, Senta; Record, Eric

    2014-09-01

    The genome of the coprophilous fungus Podospora anserina harbors a large and highly diverse set of putative lignocellulose-acting enzymes. In this study, we investigated the enzymatic diversity of a broad range of P. anserina secretomes induced by various carbon sources (dextrin, glucose, xylose, arabinose, lactose, cellobiose, saccharose, Avicel, Solka-floc, birchwood xylan, wheat straw, maize bran, and sugar beet pulp (SBP)). Compared with the Trichoderma reesei enzymatic cocktail, P. anserina secretomes displayed similar cellulase, xylanase, and pectinase activities and greater arabinofuranosidase, arabinanase, and galactanase activities. The secretomes were further tested for their capacity to supplement a T. reesei cocktail. Four of them improved significantly the saccharification yield of steam-exploded wheat straw up to 48 %. Fine analysis of the P. anserina secretomes produced with Avicel and SBP using proteomics revealed a large array of CAZymes with a high number of GH6 and GH7 cellulases, CE1 esterases, GH43 arabinofuranosidases, and AA1 laccase-like multicopper oxidases. Moreover, a preponderance of AA9 (formerly GH61) was exclusively produced in the SBP condition. This study brings additional insights into the P. anserina enzymatic machinery and will facilitate the selection of promising targets for the development of future biorefineries. PMID:24695830

  11. Structural and Biochemical Analyses of Glycoside Hydrolase Families 5 and 26 β-(1,4)-Mannanases from Podospora anserina Reveal Differences upon Manno-oligosaccharide Catalysis*

    PubMed Central

    Couturier, Marie; Roussel, Alain; Rosengren, Anna; Leone, Philippe; Stålbrand, Henrik; Berrin, Jean-Guy

    2013-01-01

    The microbial deconstruction of the plant cell wall is a key biological process that is of increasing importance with the development of a sustainable biofuel industry. The glycoside hydrolase families GH5 (PaMan5A) and GH26 (PaMan26A) endo-β-1,4-mannanases from the coprophilic ascomycete Podospora anserina contribute to the enzymatic degradation of lignocellulosic biomass. In this study, P. anserina mannanases were further subjected to detailed comparative analysis of their substrate specificities, active site organization, and transglycosylation capacity. Although PaMan5A displays a classical mode of action, PaMan26A revealed an atypical hydrolysis pattern with the release of mannotetraose and mannose from mannopentaose resulting from a predominant binding mode involving the −4 subsite. The crystal structures of PaMan5A and PaMan26A were solved at 1.4 and 2.85 Å resolution, respectively. Analysis of the PaMan26A structure supported strong interaction with substrate at the −4 subsite mediated by two aromatic residues Trp-244 and Trp-245. The PaMan26A structure appended to its family 35 carbohydrate binding module revealed a short and proline-rich rigid linker that anchored together the catalytic and the binding modules. PMID:23558681

  12. Podospora anserina Hemicellulases Potentiate the Trichoderma reesei Secretome for Saccharification of Lignocellulosic Biomass▿

    PubMed Central

    Couturier, Marie; Haon, Mireille; Coutinho, Pedro M.; Henrissat, Bernard; Lesage-Meessen, Laurence; Berrin, Jean-Guy

    2011-01-01

    To improve the enzymatic hydrolysis (saccharification) of lignocellulosic biomass by Trichoderma reesei, a set of genes encoding putative polysaccharide-degrading enzymes were selected from the coprophilic fungus Podospora anserina using comparative genomics. Five hemicellulase-encoding genes were successfully cloned and expressed as secreted functional proteins in the yeast Pichia pastoris. These novel fungal CAZymes belonging to different glycoside hydrolase families (PaMan5A and PaMan26A mannanases, PaXyn11A xylanase, and PaAbf51A and PaAbf62A arabinofuranosidases) were able to break down their predicted cognate substrates. Although PaMan5A and PaMan26A displayed similar specificities toward a range of mannan substrates, they differed in their end products, suggesting differences in substrate binding. The N-terminal CBM35 module of PaMan26A displayed dual binding specificity toward xylan and mannan. PaXyn11A harboring a C-terminal CBM1 module efficiently degraded wheat arabinoxylan, releasing mainly xylobiose as end product. PaAbf51A and PaAbf62A arabinose-debranching enzymes exhibited differences in activity toward arabinose-containing substrates. Further investigation of the contribution made by each P. anserina auxiliary enzyme to the saccharification of wheat straw and spruce demonstrated that the endo-acting hemicellulases (PaXyn11A, PaMan5A, and PaMan26A) individually supplemented the secretome of the industrial T. reesei CL847 strain. The most striking effect was obtained with PaMan5A that improved the release of total sugars by 28% and of glucose by 18%, using spruce as lignocellulosic substrate. PMID:21037302

  13. Identification of a hypothetical protein from Podospora anserina as a nitroalkane oxidase.

    PubMed

    Tormos, José R; Taylor, Alexander B; Daubner, S Colette; Hart, P John; Fitzpatrick, Paul F

    2010-06-22

    The flavoprotein nitroalkane oxidase (NAO) from Fusarium oxysporum catalyzes the oxidation of primary and secondary nitroalkanes to their respective aldehydes and ketones. Structurally, the enzyme is a member of the acyl-CoA dehydrogenase superfamily. To date no enzymes other than that from F. oxysporum have been annotated as NAOs. To identify additional potential NAOs, the available database was searched for enzymes in which the active site residues Asp402, Arg409, and Ser276 were conserved. Of the several fungal enzymes identified in this fashion, PODANSg2158 from Podospora anserina was selected for expression and characterization. The recombinant enzyme is a flavoprotein with activity on nitroalkanes comparable to the F. oxysporum NAO, although the substrate specificity is somewhat different. Asp399, Arg406, and Ser273 in PODANSg2158 correspond to the active site triad in F. oxysporum NAO. The k(cat)/K(M)-pH profile with nitroethane shows a pK(a) of 5.9 that is assigned to Asp399 as the active site base. Mutation of Asp399 to asparagine decreases the k(cat)/K(M) value for nitroethane over 2 orders of magnitude. The R406K and S373A mutations decrease this kinetic parameter by 64- and 3-fold, respectively. The structure of PODANSg2158 has been determined at a resolution of 2.0 A, confirming its identification as an NAO. PMID:20481475

  14. Genetic and Molecular Analysis of a Long-Lived Strain of Podospora Anserina

    PubMed Central

    Silliker, M. E.; Cummings, D. J.

    1990-01-01

    A genetic and molecular analysis of a long-lived strain of Podospora anserina, Mn19, was undertaken to detect mutations in genes responsible for senescence. In crosses between Mn19 and wild type about 15% of the progeny were long-lived, regardless of the female parent. Molecular analysis of the long-lived progeny showed that none of the strains inherited a mtDNA rearrangement characteristic of the Mn19 parent. Instead, all long-lived strains initially inherited wild-type mtDNA. Over time the mtDNA of most long-lived strains underwent rearrangements, deletions and amplifications. The change over time in the presence of two previously characterized plasmids associated with either senescence or longevity was monitored. Crosses between Mn19 and its long-lived progeny also yielded only a small percent of individuals recovering from senescence. Analysis of mtDNA from crosses suggests that wild-type mtDNA from the paternal parent can be selected over mtDNA from the maternal parent. The life span phenotypes of progeny were not consistent with the hypothesis that mutations in a few nuclear genes were responsible for longevity. PMID:2397883

  15. Enzymatic synthesis of model substrates recognized by glucuronoyl esterases from Podospora anserina and Myceliophthora thermophila.

    PubMed

    Katsimpouras, Constantinos; Bénarouche, Anaïs; Navarro, David; Karpusas, Michael; Dimarogona, Maria; Berrin, Jean-Guy; Christakopoulos, Paul; Topakas, Evangelos

    2014-06-01

    Glucuronoyl esterases (GEs) are recently discovered enzymes that are suggested to cleave the ester bond between lignin alcohols and xylan-bound 4-O-methyl-D-glucuronic acid. Although their potential use for enhanced enzymatic biomass degradation and synthesis of valuable chemicals renders them attractive research targets for biotechnological applications, the difficulty to purify natural fractions of lignin-carbohydrate complexes hampers the characterization of fungal GEs. In this work, we report the synthesis of three aryl alkyl or alkenyl D-glucuronate esters using lipase B from Candida antarctica (CALB) and their use to determine the kinetic parameters of two GEs, StGE2 from the thermophilic fungus Myceliophthora thermophila (syn. Sporotrichum thermophile) and PaGE1 from the coprophilous fungus Podospora anserina. PaGE1 was functionally expressed in the methylotrophic yeast Pichia pastoris under the transcriptional control of the alcohol oxidase (AOX1) promoter and purified to its homogeneity (63 kDa). The three D-glucuronate esters contain an aromatic UV-absorbing phenol group that facilitates the quantification of their enzymatic hydrolysis by HPLC. Both enzymes were able to hydrolyze the synthetic esters with a pronounced preference towards the cinnamyl-D-glucuronate ester. The experimental results were corroborated by computational docking of the synthesized substrate analogues. We show that the nature of the alcohol portion of the hydrolyzed ester influences the catalytic efficiency of the two GEs. PMID:24531271

  16. The PaPsr1 and PaWhi2 genes are members of the regulatory network that connect stationary phase to mycelium differentiation and reproduction in Podospora anserina.

    PubMed

    Timpano, Hélène; Chan Ho Tong, Laetitia; Gautier, Valérie; Lalucque, Hervé; Silar, Philippe

    2016-09-01

    In filamentous fungi, entrance into stationary phase is complex as it is accompanied by several differentiation and developmental processes, including the synthesis of pigments, aerial hyphae, anastomoses and sporophores. The regulatory networks that control these processes are still incompletely known. The analysis of the "Impaired in the development of Crippled Growth (IDC)" mutants of the model filamentous ascomycete Podospora anserina has already yielded important information regarding the pathway regulating entrance into stationary phase. Here, the genes affected in two additional IDC mutants are identified as orthologues of the Saccharomyces cerevisiae WHI2 and PSR1 genes, known to regulate stationary phase in this yeast, arguing for a conserved role of these proteins throughout the evolution of ascomycetes. PMID:27353975

  17. Incomplete penetrance and variable expressivity of a growth defect as a consequence of knocking out two K(+) transporters in the euascomycete fungus Podospora anserina.

    PubMed Central

    Lalucque, Hervé; Silar, Philippe

    2004-01-01

    We describe an example of incomplete penetrance and variable expressivity in the filamentous fungus Podospora anserina, two genetic properties classically associated with mutations in more complex organisms, such as green plants and animals. We show that the knockouts of two TRK-related K(+) transporters of this ascomycete present variability in their phenotype that cannot be attributed to fluctuations of the genetic background or the environment. Thalli of the knockout strains derived from independent monokaryotic ascospores or from a single monokaryotic ascospore and cultivated under standard growth conditions may or may not present impaired growth. When impaired, thalli exhibit a range of phenotypes. Environmental conditions control expressivity to a large extent and penetrance to a low extent. Restoration of functional potassium transport by heterologous expression of K(+) transporters from Neurospora crassa abolishes or strongly diminishes the growth impairment. These data show that incomplete penetrance and variable expressivity can be an intrinsic property of a single Mendelian loss-of-function mutation. They also show that such variability in the expression of a mutant phenotype can be promoted by a phenomenon not obviously related to the well-known chromatin structure modifications, i.e., potassium transport. They provide a framework to understand human channelopathies with similar properties. PMID:15020412

  18. Overlapping Podospora anserina Transcriptional Responses to Bacterial and Fungal Non Self Indicate a Multilayered Innate Immune Response

    PubMed Central

    Lamacchia, Marina; Dyrka, Witold; Breton, Annick; Saupe, Sven J.; Paoletti, Mathieu

    2016-01-01

    Recognition and response to non self is essential to development and survival of all organisms. It can occur between individuals of the same species or between different organisms. Fungi are established models for conspecific non self recognition in the form of vegetative incompatibility (VI), a genetically controlled process initiating a programmed cell death (PCD) leading to the rejection of a fusion cell between genetically different isolates of the same species. In Podospora anserina VI is controlled by members of the hnwd gene family encoding for proteins analogous to NOD Like Receptors (NLR) immune receptors in eukaryotes. It was hypothesized that the hnwd controlled VI reaction was derived from the fungal innate immune response. Here we analyze the P. anserina transcriptional responses to two bacterial species, Serratia fonticola to which P. anserina survives and S. marcescens to which P. anserina succumbs, and compare these to the transcriptional response induced under VI conditions. Transcriptional responses to both bacteria largely overlap, however the number of genes regulated and magnitude of regulation is more important when P. anserina survives. Transcriptional responses to bacteria also overlap with the VI reaction for both up or down regulated gene sets. Genes up regulated tend to be clustered in the genome, and display limited phylogenetic distribution. In all three responses we observed genes related to autophagy to be up-regulated. Autophagy contributes to the fungal survival in all three conditions. Genes encoding for secondary metabolites and histidine kinase signaling are also up regulated in all three conditions. Transcriptional responses also display differences. Genes involved in response to oxidative stress, or encoding small secreted proteins are essentially expressed in response to bacteria, while genes encoding NLR proteins are expressed during VI. Most functions encoded in response to bacteria favor survival of the fungus while most

  19. Maintaining Two Mating Types: Structure of the Mating Type Locus and Its Role in Heterokaryosis in Podospora anserina

    PubMed Central

    Grognet, Pierre; Bidard, Frédérique; Kuchly, Claire; Tong, Laetitia Chan Ho; Coppin, Evelyne; Benkhali, Jinane Ait; Couloux, Arnaud; Wincker, Patrick; Debuchy, Robert; Silar, Philippe

    2014-01-01

    Pseudo-homothallism is a reproductive strategy elected by some fungi producing heterokaryotic sexual spores containing genetically different but sexually compatible nuclei. This lifestyle appears as a compromise between true homothallism (self-fertility with predominant inbreeding) and complete heterothallism (with exclusive outcrossing). However, pseudohomothallic species face the problem of maintaining heterokaryotic mycelia to fully benefit from this lifestyle, as homokaryons are self-sterile. Here, we report on the structure of chromosome 1 in mat+ and mat− isolates of strain S of the pseudohomothallic fungus Podospora anserina. Chromosome 1 contains either one of the mat+ and mat− mating types of P. anserina, which is mostly found in nature as a mat+/mat− heterokaryotic mycelium harboring sexually compatible nuclei. We identified a “mat” region ∼0.8 Mb long, devoid of meiotic recombination and containing the mating-type idiomorphs, which is a candidate to be involved in the maintenance of the heterokaryotic state, since the S mat+ and S mat− strains have different physiology that may enable hybrid-vigor-like phenomena in the heterokaryons. The mat region contains 229 coding sequences. A total of 687 polymorphisms were detected between the S mat+ and S mat− chromosomes. Importantly, the mat region is colinear between both chromosomes, which calls for an original mechanism of recombination inhibition. Microarray analyses revealed that 10% of the P. anserina genes have different transcriptional profiles in S mat+ and S mat−, in line with their different phenotypes. Finally, we show that the heterokaryotic state is faithfully maintained during mycelium growth of P. anserina, yet mat+/mat+ and mat−/mat− heterokaryons are as stable as mat+/mat− ones, evidencing a maintenance of heterokaryosis that does not rely on fitness-enhancing complementation between the S mat+ and S mat− strains. PMID:24558260

  20. Cytosolic Ribosomal Mutations That Abolish Accumulation of Circular Intron in the Mitochondria without Preventing Senescence of Podospora Anserina

    PubMed Central

    Silar, P.; Koll, F.; Rossignol, M.

    1997-01-01

    The filamentous fungus Podospora anserina presents a degeneration syndrome called Senescence associated with mitochondrial DNA modifications. We show that mutations affecting the two different and interacting cytosolic ribosomal proteins (S7 and S19) systematically and specifically prevent the accumulation of senDNAα (a circular double-stranded DNA plasmid derived from the first intron of the mitochondrial cox1 gene or intron α) without abolishing Senescence nor affecting the accumulation of other usually observed mitochondrial DNA rearrangements. One of the mutant proteins is homologous to the Escherichia coli S4 and Saccharomyces cerevisiae S13 ribosomal proteins, known to be involved in accuracy control of cytosolic translation. The lack of accumulation of senDNAα seems to result from a nontrivial ribosomal alteration unrelated to accuracy control, indicating that S7 and S19 proteins have an additional function. The results strongly suggest that modified expression of nucleus-encoded proteins contributes to Senescence in P. anserina. These data do not fit well with some current models, which propose that intron α plays the role of the cytoplasmic and infectious Determinant of Senescence that was defined in early studies. PMID:9055079

  1. Altering a gene involved in nuclear distribution increases the repeat-induced point mutation process in the fungus Podospora anserina.

    PubMed Central

    Bouhouche, Khaled; Zickler, Denise; Debuchy, Robert; Arnaise, Sylvie

    2004-01-01

    Repeat-induced point mutation (RIP) is a homology-dependent gene-silencing mechanism that introduces C:G-to-T:A transitions in duplicated DNA segments. Cis-duplicated sequences can also be affected by another mechanism called premeiotic recombination (PR). Both are active over the sexual cycle of some filamentous fungi, e.g., Neurospora crassa and Podospora anserina. During the sexual cycle, several developmental steps require precise nuclear movement and positioning, but connections between RIP, PR, and nuclear distributions have not yet been established. Previous work has led to the isolation of ami1, the P. anserina ortholog of the Aspergillus nidulans apsA gene, which is required for nuclear positioning. We show here that ami1 is involved in nuclear distribution during the sexual cycle and that alteration of ami1 delays the fruiting-body development. We also demonstrate that ami1 alteration affects loss of transgene functions during the sexual cycle. Genetically linked multiple copies of transgenes are affected by RIP and PR much more frequently in an ami1 mutant cross than in a wild-type cross. Our results suggest that the developmental slowdown of the ami1 mutant during the period of RIP and PR increases time exposure to the duplication detection system and thus increases the frequency of RIP and PR. PMID:15166143

  2. Co-expression of the mating-type genes involved in internuclear recognition is lethal in Podospora anserina.

    PubMed Central

    Coppin, E; Debuchy, R

    2000-01-01

    In the heterothallic filamentous fungus Podospora anserina, four mating-type genes encoding transcriptional factors have been characterized: FPR1 in the mat+ sequence and FMR1, SMR1, and SMR2 in the alternative mat- sequence. Fertilization is controlled by FPR1 and FMR1. After fertilization, male and female nuclei, which have divided in the same cell, form mat+/mat- pairs during migration into the ascogenous hyphae. Previous data indicate that the formation of mat+/mat- pairs is controlled by FPR1, FMR1, and SMR2. SMR1 was postulated to be necessary for initial development of ascogenous hyphae. In this study, we investigated the transcriptional control of the mat genes by seeking mat transcripts during the vegetative and sexual phase and fusing their promoter to a reporter gene. The data indicate that FMR1 and FPR1 are expressed in both mycelia and perithecia, whereas SMR1 and SMR2 are transcribed in perithecia. Increased or induced vegetative expression of the four mat genes has no effect when the recombined gene is solely in the wild-type strain. However, the combination of resident FPR1 with deregulated SMR2 and overexpressed FMR1 in the same nucleus is lethal. This lethality is suppressed by the expression of SMR1, confirming that SMR1 operates downstream of the other mat genes. PMID:10835389

  3. Regulation of gene expression during the vegetative incompatibility reaction in Podospora anserina. Characterization of three induced genes.

    PubMed Central

    Bourges, N; Groppi, A; Barreau, C; Clavé, C; Bégueret, J

    1998-01-01

    Vegetative incompatibility in fungi limits the formation of viable heterokaryons. It results from the coexpression of incompatible genes in the heterokaryotic cells and leads to a cell death reaction. In Podospora anserina, a modification of gene expression takes place during this reaction, including a strong decrease of total RNA synthesis and the appearance of a new set of proteins. Using in vitro translation of mRNA and separation of protein products by two-dimensional gel electrophoresis, we have shown that the mRNA content of cells is qualitatively modified during the progress of the incompatibility reaction. Thus, gene expression during vegetative incompatibility is regulated, at least in part, by variation of the mRNA content of specific genes. A subtractive cDNA library enriched in sequences preferentially expressed during incompatibility was constructed. This library was used to identify genomic loci corresponding to genes whose mRNA is induced during incompatibility. Three such genes were characterized and named idi genes for genes induced during incompatibility. Their expression profiles suggest that they may be involved in different steps of the incompatibility reaction. The putative IDI proteins encoded by these genes are small proteins with signal peptides. IDI-2 protein is a cysteine-rich protein. IDI-2 and IDI-3 proteins display some similarity in a tryptophan-rich region. PMID:9755195

  4. Genetic and functional investigation of Zn(2)Cys(6) transcription factors RSE2 and RSE3 in Podospora anserina.

    PubMed

    Bovier, Elodie; Sellem, Carole H; Humbert, Adeline; Sainsard-Chanet, Annie

    2014-01-01

    In Podospora anserina, the two zinc cluster proteins RSE2 and RSE3 are essential for the expression of the gene encoding the alternative oxidase (aox) when the mitochondrial electron transport chain is impaired. In parallel, they activated the expression of gluconeogenic genes encoding phosphoenolpyruvate carboxykinase (pck) and fructose-1,6-biphosphatase (fbp). Orthologues of these transcription factors are present in a wide range of filamentous fungi, and no other role than the regulation of these three genes has been evidenced so far. In order to better understand the function and the organization of RSE2 and RSE3, we conducted a saturated genetic screen based on the constitutive expression of the aox gene. We identified 10 independent mutations in 9 positions in rse2 and 11 mutations in 5 positions in rse3. Deletions were generated at some of these positions and the effects analyzed. This analysis suggests the presence of central regulatory domains and a C-terminal activation domain in both proteins. Microarray analysis revealed 598 genes that were differentially expressed in the strains containing gain- or loss-of-function mutations in rse2 or rse3. It showed that in addition to aox, fbp, and pck, RSE2 and RSE3 regulate the expression of genes encoding the alternative NADH dehydrogenase, a Zn2Cys6 transcription factor, a flavohemoglobin, and various hydrolases. As a complement to expression data, a metabolome profiling approach revealed that both an rse2 gain-of-function mutation and growth on antimycin result in similar metabolic alterations in amino acids, fatty acids, and α-ketoglutarate pools. PMID:24186951

  5. Biological Roles of the Podospora anserina Mitochondrial Lon Protease and the Importance of Its N-Domain

    PubMed Central

    Adam, Céline; Picard, Marguerite; Déquard-Chablat, Michelle; Sellem, Carole H.; Denmat, Sylvie Hermann-Le; Contamine, Véronique

    2012-01-01

    Mitochondria have their own ATP-dependent proteases that maintain the functional state of the organelle. All multicellular eukaryotes, including filamentous fungi, possess the same set of mitochondrial proteases, unlike in unicellular yeasts, where ClpXP, one of the two matricial proteases, is absent. Despite the presence of ClpXP in the filamentous fungus Podospora anserina, deletion of the gene encoding the other matricial protease, PaLon1, leads to lethality at high and low temperatures, indicating that PaLON1 plays a main role in protein quality control. Under normal physiological conditions, the PaLon1 deletion is viable but decreases life span. PaLon1 deletion also leads to defects in two steps during development, ascospore germination and sexual reproduction, which suggests that PaLON1 ensures important regulatory functions during fungal development. Mitochondrial Lon proteases are composed of a central ATPase domain flanked by a large non-catalytic N-domain and a C-terminal protease domain. We found that three mutations in the N-domain of PaLON1 affected fungal life cycle, PaLON1 protein expression and mitochondrial proteolytic activity, which reveals the functional importance of the N-domain of the mitochondrial Lon protease. All PaLon1 mutations affected the C-terminal part of the N-domain. Considering that the C-terminal part is predicted to have an α helical arrangement in which the number, length and position of the helices are conserved with the solved structure of its bacterial homologs, we propose that this all-helical structure participates in Lon substrate interaction. PMID:22693589

  6. Deletion of the MED13 and CDK8 subunits of the Mediator improves the phenotype of a long-lived respiratory deficient mutant of Podospora anserina.

    PubMed

    Humbert, Adeline; Bovier, Elodie; Sellem, Carole H; Sainsard-Chanet, Annie

    2015-09-01

    In Podospora anserina, the loss of function of the cytochrome segment of the mitochondrial respiratory chain is viable. This is due to the presence in this organism, as in most filamentous fungi, of an alternative respiratory oxidase (AOX) that provides a bypass to the cytochrome pathway. However mutants lacking a functional cytochrome pathway present multiple phenotypes including poorly colored thin mycelium and slow growth. In a large genetic screen based on the improvement of these phenotypes, we isolated a large number of independent suppressor mutations. Most of them led to the constitutive overexpression of the aox gene. In this study, we characterize a new suppressor mutation that does not affect the production of AOX. It is a loss-of-function mutation in the gene encoding the MED13 subunit of the kinase module of the Mediator complex. Inactivation of the cdk8 gene encoding another subunit of the same module also results in partial suppression of a cytochrome-deficient mutant. Analysis of strains lacking the MED13 or CDK8 subunits points to the importance of these subunits as regulators involved in diverse physiological processes such as growth, longevity and sexual development. Interestingly, transcriptional analyses indicate that in P. anserina, loss of the respiratory cytochrome pathway results in the up-regulation of glycolysis-related genes revealing a new type of retrograde regulation. The loss of MED13 augments the up-regulation of some of these genes. PMID:26231682

  7. Regulation of Aerobic Energy Metabolism in Podospora anserina by Two Paralogous Genes Encoding Structurally Different c-Subunits of ATP Synthase

    PubMed Central

    Sellem, Carole H.; di Rago, Jean-Paul; Lasserre, Jean-Paul; Ackerman, Sharon H.; Sainsard-Chanet, Annie

    2016-01-01

    Most of the ATP in living cells is produced by an F-type ATP synthase. This enzyme uses the energy of a transmembrane electrochemical proton gradient to synthesize ATP from ADP and inorganic phosphate. Proton movements across the membrane domain (FO) of the ATP synthase drive the rotation of a ring of 8–15 c-subunits, which induces conformational changes in the catalytic part (F1) of the enzyme that ultimately promote ATP synthesis. Two paralogous nuclear genes, called Atp9-5 and Atp9-7, encode structurally different c-subunits in the filamentous fungus Podospora anserina. We have in this study identified differences in the expression pattern for the two genes that correlate with the mitotic activity of cells in vegetative mycelia: Atp9-7 is transcriptionally active in non-proliferating (stationary) cells while Atp9-5 is expressed in the cells at the extremity (apex) of filaments that divide and are responsible for mycelium growth. When active, the Atp9-5 gene sustains a much higher rate of c-subunit synthesis than Atp9-7. We further show that the ATP9-7 and ATP9-5 proteins have antagonist effects on the longevity of P. anserina. Finally, we provide evidence that the ATP9-5 protein sustains a higher rate of mitochondrial ATP synthesis and yield in ATP molecules per electron transferred to oxygen than the c-subunit encoded by Atp9-7. These findings reveal that the c-subunit genes play a key role in the modulation of ATP synthase production and activity along the life cycle of P. anserina. Such a degree of sophistication for regulating aerobic energy metabolism has not been described before. PMID:27442014

  8. Identification of the het-r vegetative incompatibility gene of Podospora anserina as a member of the fast evolving HNWD gene family.

    PubMed

    Chevanne, Damien; Bastiaans, Eric; Debets, Alfons; Saupe, Sven J; Clavé, Corinne; Paoletti, Mathieu

    2009-02-01

    In fungi, vegetative incompatibility is a conspecific non-self recognition mechanism that restricts formation of viable heterokaryons when incompatible alleles of specific het loci interact. In Podospora anserina, three non-allelic incompatibility systems have been genetically defined involving interactions between het-c and het-d, het-c and het-e, het-r and het-v. het-d and het-e are paralogues belonging to the HNWD gene family that encode proteins of the STAND class. HET-D and HET-E proteins comprise an N-terminal HET effector domain, a central GTP binding site and a C-terminal WD repeat domain constituted of tandem repeats of highly conserved WD40 repeat units that define the specificity of alleles during incompatibility. The WD40 repeat units of the members of this HNWD family are undergoing concerted evolution. By combining genetic analysis and gain of function experiments, we demonstrate that an additional member of this family, HNWD2, corresponds to the het-r non-allelic incompatibility gene. As for het-d and het-e, allele specificity at the het-r locus is determined by the WD repeat domain. Natural isolates show allelic variation for het-r. PMID:19137300

  9. eEF1A Controls ascospore differentiation through elevated accuracy, but controls longevity and fruiting body formation through another mechanism in Podospora anserina.

    PubMed Central

    Silar, P; Lalucque, H; Haedens, V; Zickler, D; Picard, M

    2001-01-01

    Antisuppressor mutations in the eEF1A gene of Podospora anserina were previously shown to impair ascospore formation, to drastically increase life span, and to permit the development of the Crippled Growth degenerative process. Here, we show that eEF1A controls ascospore formation through accuracy level maintenance. Examination of antisuppressor mutant perithecia reveals two main cytological defects, mislocalization of spindle and nuclei and nuclear death. Antisuppression levels are shown to be highly dependent upon both the mutation site and the suppressor used, precluding any correlation between antisuppression efficiency and severity of the sporulation impairment. Nevertheless, severity of ascospore differentiation defect is correlated with resistance to paromomycin. We also show that eEF1A controls fruiting body formation and longevity through a mechanism(s) different from accuracy control. In vivo, GFP tagging of the protein in a way that partly retains its function confirmed earlier cytological observation; i.e., this factor is mainly diffuse within the cytosol, but may transiently accumulate within nuclei or in defined regions of the cytoplasm. These data emphasize the fact that the translation apparatus exerts a global regulatory control over cell physiology and that eEF1A is one of the key factors involved in this monitoring. PMID:11514440

  10. A homologue of the yeast SHE4 gene is essential for the transition between the syncytial and cellular stages during sexual reproduction of the fungus Podospora anserina.

    PubMed Central

    Berteaux-Lecellier, V; Zickler, D; Debuchy, R; Panvier-Adoutte, A; Thompson-Coffe, C; Picard, M

    1998-01-01

    The Podospora anserina cro1 gene was identified as a gene required for sexual sporulation. Crosses homozygous for the cro1-1 mutation yield fruiting bodies which produce few asci due to the formation of giant plurinucleate cells instead of dikaryotic cells after fertilization. This defect does not impair karyogamy, but meioses of the resultant polyploid nuclei are most often abortive. Cytological studies suggest that the primary defect of the mutant is its inability to form septa between the daughter nuclei after each mitosis, a step specific for normal dikaryotic cell divisions. The cro1-1 mutant would thus be unable to leave the syncytial vegetative state while abiding by the meiotic programme. cro1-1 also shows defects in ascospore germination and growth rate. GFP-tagging of the CRO1 protein reveals that it is a cytosolic protein mainly expressed at the beginning of the dikaryotic stage and at the time of ascospore maturation. The CRO1 protein exhibits significant similarity to the SHE4 protein, which is required for asymmetric mating-type switching in budding yeast cells. Thus, a gene involved in asymmetric cell divisions in a unicellular organism plays a key role at the transition between the syncytial (vegetative) state and the cellular (sexual) state in a filamentous fungus. PMID:9482722

  11. ami1, an orthologue of the Aspergillus nidulans apsA gene, is involved in nuclear migration events throughout the life cycle of Podospora anserina.

    PubMed Central

    Graïa, F; Berteaux-Lecellier, V; Zickler, D; Picard, M

    2000-01-01

    The Podospora anserina ami1-1 mutant was identified as a male-sterile strain. Microconidia (which act as male gametes) form, but are anucleate. Paraphysae from the perithecium beaks are also anucleate when ami1-1 is used as the female partner in a cross. Furthermore, in crosses heterozygous for ami1-1, some crozier cells are uninucleate rather than binucleate. In addition to these nuclear migration defects, which occur at the transition between syncytial and cellular states, ami1-1 causes abnormal distribution of the nuclei in both mycelial filaments and asci. Finally, an ami1-1 strain bearing information for both mating types is unable to self-fertilize. The ami1 gene is an orthologue of the Aspergillus nidulans apsA gene, which controls nuclear positioning in filaments and during conidiogenesis (at the syncytial/cellular transition). The ApsA and AMI1 proteins display 42% identity and share structural features. The apsA gene complements some ami1-1 defects: it increases the percentage of nucleate microconidia and restores self-fertility in an ami1-1 mat+ (mat-) strain. The latter effect is puzzling, since in apsA null mutants sexual reproduction is quite normal. The functional differences between the two genes are discussed with respect to their possible history in these two fungi, which are very distant in terms of evolution. PMID:10835387

  12. Structure and Biophysical Characterization of the S-Adenosylmethionine-dependent O-Methyltransferase PaMTH1, a Putative Enzyme Accumulating during Senescence of Podospora anserina.

    PubMed

    Chatterjee, Deep; Kudlinzki, Denis; Linhard, Verena; Saxena, Krishna; Schieborr, Ulrich; Gande, Santosh L; Wurm, Jan Philip; Wöhnert, Jens; Abele, Rupert; Rogov, Vladimir V; Dötsch, Volker; Osiewacz, Heinz D; Sreeramulu, Sridhar; Schwalbe, Harald

    2015-06-26

    Low levels of reactive oxygen species (ROS) act as important signaling molecules, but in excess they can damage biomolecules. ROS regulation is therefore of key importance. Several polyphenols in general and flavonoids in particular have the potential to generate hydroxyl radicals, the most hazardous among all ROS. However, the generation of a hydroxyl radical and subsequent ROS formation can be prevented by methylation of the hydroxyl group of the flavonoids. O-Methylation is performed by O-methyltransferases, members of the S-adenosyl-l-methionine (SAM)-dependent O-methyltransferase superfamily involved in the secondary metabolism of many species across all kingdoms. In the filamentous fungus Podospora anserina, a well established aging model, the O-methyltransferase (PaMTH1) was reported to accumulate in total and mitochondrial protein extracts during aging. In vitro functional studies revealed flavonoids and in particular myricetin as its potential substrate. The molecular architecture of PaMTH1 and the mechanism of the methyl transfer reaction remain unknown. Here, we report the crystal structures of PaMTH1 apoenzyme, PaMTH1-SAM (co-factor), and PaMTH1-S-adenosyl homocysteine (by-product) co-complexes refined to 2.0, 1.9, and 1.9 Å, respectively. PaMTH1 forms a tight dimer through swapping of the N termini. Each monomer adopts the Rossmann fold typical for many SAM-binding methyltransferases. Structural comparisons between different O-methyltransferases reveal a strikingly similar co-factor binding pocket but differences in the substrate binding pocket, indicating specific molecular determinants required for substrate selection. Furthermore, using NMR, mass spectrometry, and site-directed active site mutagenesis, we show that PaMTH1 catalyzes the transfer of the methyl group from SAM to one hydroxyl group of the myricetin in a cation-dependent manner. PMID:25979334

  13. Structure and Biophysical Characterization of the S-Adenosylmethionine-dependent O-Methyltransferase PaMTH1, a Putative Enzyme Accumulating during Senescence of Podospora anserina *

    PubMed Central

    Chatterjee, Deep; Kudlinzki, Denis; Linhard, Verena; Saxena, Krishna; Schieborr, Ulrich; Gande, Santosh L.; Wurm, Jan Philip; Wöhnert, Jens; Abele, Rupert; Rogov, Vladimir V.; Dötsch, Volker; Osiewacz, Heinz D.; Sreeramulu, Sridhar; Schwalbe, Harald

    2015-01-01

    Low levels of reactive oxygen species (ROS) act as important signaling molecules, but in excess they can damage biomolecules. ROS regulation is therefore of key importance. Several polyphenols in general and flavonoids in particular have the potential to generate hydroxyl radicals, the most hazardous among all ROS. However, the generation of a hydroxyl radical and subsequent ROS formation can be prevented by methylation of the hydroxyl group of the flavonoids. O-Methylation is performed by O-methyltransferases, members of the S-adenosyl-l-methionine (SAM)-dependent O-methyltransferase superfamily involved in the secondary metabolism of many species across all kingdoms. In the filamentous fungus Podospora anserina, a well established aging model, the O-methyltransferase (PaMTH1) was reported to accumulate in total and mitochondrial protein extracts during aging. In vitro functional studies revealed flavonoids and in particular myricetin as its potential substrate. The molecular architecture of PaMTH1 and the mechanism of the methyl transfer reaction remain unknown. Here, we report the crystal structures of PaMTH1 apoenzyme, PaMTH1-SAM (co-factor), and PaMTH1-S-adenosyl homocysteine (by-product) co-complexes refined to 2.0, 1.9, and 1.9 Å, respectively. PaMTH1 forms a tight dimer through swapping of the N termini. Each monomer adopts the Rossmann fold typical for many SAM-binding methyltransferases. Structural comparisons between different O-methyltransferases reveal a strikingly similar co-factor binding pocket but differences in the substrate binding pocket, indicating specific molecular determinants required for substrate selection. Furthermore, using NMR, mass spectrometry, and site-directed active site mutagenesis, we show that PaMTH1 catalyzes the transfer of the methyl group from SAM to one hydroxyl group of the myricetin in a cation-dependent manner. PMID:25979334

  14. Mating types and sexual development in filamentous ascomycetes.

    PubMed Central

    Coppin, E; Debuchy, R; Arnaise, S; Picard, M

    1997-01-01

    The progress made in the molecular characterization of the mating types in several filamentous ascomycetes has allowed us to better understand their role in sexual development and has brought to light interesting biological problems. The mating types of Neurospora crassa, Podospora anserina, and Cochliobolus heterostrophus consist of unrelated and unique sequences containing one or several genes with multiple functions, related to sexuality or not, such as vegetative incompatibility in N. crassa. The presence of putative DNA binding domains in the proteins encoded by the mating-type (mat) genes suggests that they may be transcriptional factors. The mat genes play a role in cell-cell recognition at fertilization, probably by activating the genes responsible for the hormonal signal whose occurrence was previously demonstrated by physiological experiments. They also control recognition between nuclei at a later stage, when reproductive nuclei of each mating type which have divided in the common cytoplasm pair within the ascogenous hyphae. How self is distinguished from nonself at the nuclear level is not known. The finding that homothallic species, able to mate in the absence of a partner, contain both mating types in the same haploid genome has raised more issues than it has resolved. The instability of the mating type, in particular in Sclerotinia trifolorium and Botrytinia fuckeliana, is also unexplained. This diversity of mating systems, still more apparent if the yeasts and the basidiomycetes are taken into account, clearly shows that no single species can serve as a universal mating-type model. PMID:9409146

  15. The Podospora rmp1 gene implicated in nucleus-mitochondria cross-talk encodes an essential protein whose subcellular location is developmentally regulated.

    PubMed Central

    Contamine, Véronique; Zickler, Denise; Picard, Marguerite

    2004-01-01

    It has been previously reported that, at the time of death, the Podospora anserina AS1-4 mutant strains accumulate specific deleted forms of the mitochondrial genome and that their life spans depend on two natural alleles (variants) of the rmp1 gene: AS1-4 rmp1-2 strains exhibit life spans strikingly longer than those of AS1-4 rmp1-1. Here, we show that rmp1 is an essential gene. In silico analyses of eight rmp1 natural alleles present in Podospora isolates and of the putative homologs of this orphan gene in other filamentous fungi suggest that rmp1 evolves rapidly. The RMP1 protein is localized in the mitochondrial and/or the cytosolic compartment, depending on cell type and developmental stage. Strains producing RMP1 without its mitochondrial targeting peptide are viable but exhibit vegetative and sexual defects. PMID:15020413

  16. A Genome-Wide Longitudinal Transcriptome Analysis of the Aging Model Podospora anserine

    PubMed Central

    Philipp, Oliver; Hamann, Andrea; Servos, Jörg; Werner, Alexandra; Koch, Ina; Osiewacz, Heinz D.

    2013-01-01

    Aging of biological systems is controlled by various processes which have a potential impact on gene expression. Here we report a genome-wide transcriptome analysis of the fungal aging model Podospora anserina. Total RNA of three individuals of defined age were pooled and analyzed by SuperSAGE (serial analysis of gene expression). A bioinformatics analysis identified different molecular pathways to be affected during aging. While the abundance of transcripts linked to ribosomes and to the proteasome quality control system were found to decrease during aging, those associated with autophagy increase, suggesting that autophagy may act as a compensatory quality control pathway. Transcript profiles associated with the energy metabolism including mitochondrial functions were identified to fluctuate during aging. Comparison of wild-type transcripts, which are continuously down-regulated during aging, with those down-regulated in the long-lived, copper-uptake mutant grisea, validated the relevance of age-related changes in cellular copper metabolism. Overall, we (i) present a unique age-related data set of a longitudinal study of the experimental aging model P. anserina which represents a reference resource for future investigations in a variety of organisms, (ii) suggest autophagy to be a key quality control pathway that becomes active once other pathways fail, and (iii) present testable predictions for subsequent experimental investigations. PMID:24376646

  17. Podospora anserina mutant defective in protoperithecium formation, ascospore germination, and cell regeneration.

    PubMed Central

    Durrens, P; Laigret, F; Labarère, J; Bernet, J

    1979-01-01

    A mutant (modx) was selected on the basis of the suppression of self-lysis due to a recessive mutation (modB). modx, a dominant mutation, reduced hyphal branching from nonapical cells, abolished protoperithecium formation, and induced the death of stationary cells only when these were isolated to obtain further development. Mutant ascospores, formed in the fruiting bodies which occasionally occur under specific conditions (32 degrees C on starved medium), showed a delay in the germination process (up to 3 months instead of about 5 h for wild-type ascospores) when submitted to incubation under standard conditions (26 degrees C on germination medium) and failed to germinate at 18 degrees C. Revertants from modx strains, selected on the basis of the suppression of the nonrenewal of growth from stationary cells, were wild type for all the other three defects. Indirect arguments suggested that the modx mutant strain might be defective in the control of a specific class of stable messenger ribonucleic acids which would be essential for the physiology of ascospores and stationary cells. Images PMID:118158

  18. Phylogeny of filamentous ascomycetes

    NASA Astrophysics Data System (ADS)

    Lumbsch, H. T.

    Phylogenetic studies of higher ascomycetes are enhanced by the introduction of molecular markers. Most studies employed sequences of the SSU rRNA gene, but recently data from additional genes (RPB2, LSU rRNA) have become available. Several groups defined by their ascoma-type, such as Pyrenomycetes, are supported while others, like the Discomycetes, appear to be paraphyletic. The Pezizales with operculate asci are basal to other eu-ascomycetes, while other Discomycetes appear to be derived eu-ascomycetes. The re-evaluation of classical characters using molecular data is discussed using three examples. Ascus types are often regarded as being of major importance in ascomycete systematics, but prototunicate asci were found to be of poor taxonomic value, since ascomycetes with prototunicate asci are polyphyletic. The independence of the Agyriales, assumed from their morphological characters, is supported by sequence data but the relationship to supposed sister groups remains dubious. The phylogeny of ascolocularous fungi and their circumscription requires further study. While a circumscription based on bitunicate asci can be rejected, it remains unclear whether fungi with ascolocularous ascoma development represent a monophyletic entity.

  19. DNA-dependent RNA polymerase III from the fungus Podospora comata. Purification, subunit structure and comparison with the homologous enzyme of a related species.

    PubMed

    Barreau, C; Begueret, J

    1982-12-15

    DNA-dependent RNA polymerase III has been purified to homogeneity from the filamentous fungus Podospora comata. The enzyme was extracted at low ionic strength, separated from the polymerases I and II by DEAE-Sephadex chromatography and purified by heparin-Sepharose and phosphocellulose chromatography; 0.1-0.2 mg highly purified homogeneous enzyme with a specific activity of 220 units/mg could be obtained from 2 kg wet mycelium. The subunit composition of the enzyme was determined after sodium dodecyl sulphate/polyacrylamide gel electrophoresis; thirteen putative subunits of molecular weight 174000 (a), 129000 b), 87000 (c), 50000 (d), 39000 (e), 23500 (f), 21000 (g), 19000 (h), 17000 (i), 16500 (j), 13500 (k), 11000 (l) and 10000 (m) were identified. All of the polypeptide components of the enzyme are present in about integral stoichiometric amounts as judged by dye binding. The presence of subunit Mr = 87000 in a molar ratio 1:1 is necessary to obtain very active enzyme. Thirteen homologous subunits were observed in a preparation of RNA polymerase III from Podospora anserina, which is a related species. Only subunit i is different in the two species. PMID:7151805

  20. Evolutionary history of Ascomyceteous Yeasts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yeasts are important for many industrial and biotechnological processes and show remarkable diversity despite morphological similarities. We have sequenced the genomes of 20 ascomyceteous yeasts of taxonomic and industrial importance including members of Saccharomycotina and Taphrinomycotina. A comp...

  1. Identification of six loci in which mutations partially restore peroxisome biogenesis and/or alleviate the metabolic defect of pex2 mutants in podospora.

    PubMed Central

    Ruprich-Robert, Gwenaël; Berteaux-Lecellier, Véronique; Zickler, Denise; Panvier-Adoutte, Arlette; Picard, Marguerite

    2002-01-01

    Peroxins (PEX) are proteins required for peroxisome biogenesis. Mutations in PEX genes cause lethal diseases in humans, metabolic defects in yeasts, and developmental disfunctions in plants and filamentous fungi. Here we describe the first large-scale screening for suppressors of a pex mutation. In Podospora anserina, pex2 mutants exhibit a metabolic defect [inability to grow on medium containing oleic acid (OA medium) as sole carbon source] and a developmental defect (inability to differentiate asci in homozygous crosses). Sixty-three mutations able to restore growth of pex2 mutants on OA medium have been analyzed. They fall in six loci (suo1 to suo6) and act as dominant, allele-nonspecific suppressors. Most suo mutations have pleiotropic effects in a pex2(+) background: formation of unripe ascospores (all loci except suo5 and suo6), impaired growth on OA medium (all loci except suo4 and suo6), or sexual defects (suo4). Using immunofluorescence and GFP staining, we show that peroxisome biogenesis is partially restored along with a low level of ascus differentiation in pex2 mutant strains carrying either the suo5 or the suo6 mutations. The data are discussed with respect to beta-oxidation of fatty acids, peroxisome biogenesis, and cell differentiation. PMID:12136013

  2. Genomic evolution of the ascomycetous yeasts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yeasts are important for industrial and biotechnological processes and show remarkable metabolic and phylogenetic diversity despite morphological similarities. We have sequenced the genomes of 16 ascomycete yeasts of taxonomic and industrial importance including members of Saccharomycotina and Taphr...

  3. PHYLOGENETICS OF SACCHAROMYCETALES, THE ASCOMYCETE YEASTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ascomycete yeasts (Phylum Ascomycota: Subphylum Saccharomycotina: Class Saccharomycetes: Order Saccharomycetales) comprise a monophyletic lineage with a single order of about 1000 known species. These yeasts live as saprobes, often in association with plants, animals, and their interfaces. A few s...

  4. Inactivation of the Podospora anserina vegetative incompatibility locus het-c, whose product resembles a glycolipid transfer protein, drastically impairs ascospore production.

    PubMed Central

    Saupe, S; Descamps, C; Turcq, B; Bégueret, J

    1994-01-01

    The het-c locus contains different alleles that elicit nonallelic vegetative incompatibility through specific interactions with alleles of the unlinked loci het-e and het-d. The het-c2 allele has been cloned. It encodes a 208-amino acid polypeptide that is similar to a glycolipid transfer protein purified from pig brain. Disruption of this gene drastically impairs ascospore production in homozygous crosses, and some mutants exhibit abnormal branching of apical hyphae. The protein encoded by het-c2 is essential in the biology of the fungus and may be involved in cell-wall biosynthesis. Images PMID:8016091

  5. Species Diversity of Hypogeous Ascomycetes in Israel

    PubMed Central

    Wasser, Solomon P.

    2010-01-01

    We conducted a species diversity study of the hypogeous Ascomycetes of Israel. The hypogeous Ascomycetes in Israel include members of the families Pyronemataceae, Pezizaceae, and Tuberaceae, which are represented by seven species: Hydnocystis piligera, Terfezia arenaria, T. claveryi, T. oligosperma, Tirmania africana, Tuber asa, and T. nitidum; only T. asa is new to Israeli mycobiota. Synonymy, locations, collection data, general distribution, distribution in Israel, descriptions, a key to identification, illustrations, and taxonomic remarks are provided. PMID:23956647

  6. Acylated proteins in Borrelia hermsii, Borrelia parkeri, Borrelia anserina, and Borrelia coriaceae.

    PubMed Central

    Sambri, V; Stefanelli, C; Rossoni, C; La Placa, M; Cevenini, R

    1993-01-01

    Borrelia hermsii, Borrelia parkeri, Borrelia anserina, and Borrelia coriaceae produced several lipoproteins identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and fluorography of bacteria grown in [3H]palmitate. Five major acylated proteins were demonstrated by sequential alkaline and acid hydrolysis. High-pressure liquid chromatography of isolated proteins confirmed that covalently bound radioactivity was represented by fatty acids. Images PMID:8285697

  7. Mitochondrial intronic open reading frames in Podospora: Mobility and consecutive exonic sequence variations

    SciTech Connect

    Sellem, C.H.; Rossignol, M.; Belcour, L.

    1996-06-01

    The mitochondrial genome of 23 wild-type strains belonging to three different species of the filamentous fungus Podospora was examined. Among the 15 optical sequences identified are two intronic reading frames, nad1-i4-orf1 and cox1-i7-orf2. We show that the presence of these sequences was strictly correlated with tightly clustered nucleotide substitutions in the adjacent exon. This correlation applies to the presence or absence of closely related open reading frames (ORFs), found at the same genetic locations, in all the Pyrenomycete genera examined. The recent gain of these optional ORFs in the evolution of the genus Podospora probably account for such sequence differences. In the homoplasmic progeny from heteroplasmons constructed between Podospora strains differing by the presence of these optional ORFs, nad1-i4-orf1 and cox1-i7-orf2 appeared highly invasive. Sequence comparisons in the nad1-i4 intron of various strains of the Pyrenomycete family led us to propose a scenario of its evolution that includes several events of loss and gain of intronic ORFs. These results strongly reinforce the idea that group I intronic ORFs are mobile elements and that their transfer, and comcomitant modification of the adjacent exon, could participate in the modular evolution of mitochondrial genomes. 46 refs., 5 figs., 2 tabs.

  8. The Kinetochore Interaction Network (KIN) of ascomycetes

    PubMed Central

    Freitag, Michael

    2016-01-01

    Chromosome segregation relies on coordinated activity of a large assembly of proteins, the “Kinetochore Interaction Network” (KIN). How conserved the underlying mechanisms driving the epigenetic phenomenon of centromere and kinetochore assembly and maintenance are remains unclear, even though various eukaryotic models have been studied. More than 50 different proteins, many in multiple copies, comprise the KIN or are associated with fungal centromeres and kinetochores. Proteins isolated from immune sera recognized centromeric regions on chromosomes and were thus named centromere proteins (“CENPs”). CENP-A, sometimes called “centromere-specific H3” (CenH3), is incorporated into nucleosomes within or near centromeres. The “constitutive centromere-associated network” (CCAN) assembles on this specialized chromatin, likely based on specific interactions with and requiring presence of CENP-C. The outer kinetochore comprises the Knl1-Mis12-Ndc80 (“KMN”) protein complexes that connect the CCAN to spindles, accomplished by binding and stabilizing microtubules (MTs) and in the process generating load-bearing assemblies for chromatid segregation. In most fungi the Dam1/DASH complex connects the KMN complexes to MTs. Fungi present a rich resource to investigate mechanistic commonalities but also differences in kinetochore architecture. While ascomycetes have sets of CCAN and KMN proteins that are conserved with those of either budding yeast or metazoans, searching other major branches of the fungal kingdom revealed that CCAN proteins are poorly conserved at the primary sequence level. Several conserved binding motifs or domains within KMN complexes have been described recently, and these features of ascomycete KIN proteins are shared with most metazoan proteins. In addition, several ascomycete-specific domains have been identified here. PMID:26908646

  9. Dibenzofurans and derivatives from lichens and ascomycetes.

    PubMed

    Millot, Marion; Dieu, Amandine; Tomasi, Sophie

    2016-06-01

    Covering: up to 2016.When looking for dibenzofuran in the biochemical databases, most papers and reviews deal with pollutants and polychlorinated dibenzofurans like dioxins. But dibenzofurans are also biosynthetized by a wide diversity of organisms in nature. Even if dibenzofurans from natural sources represent a small class of secondary metabolites, compared to flavonoids, xanthones or terpenoids, they are often endowed with interesting biological properties which have been recently described. This review provides an update on papers describing dibenzofurans from lichens, ascomycetes and cultured mycobionts. Other sources, such as basidiomycetes, myxomycetes or plants produce sporadically interesting dibenzofurans in terms of structures and activities. PMID:26867808

  10. Genomic Evolution of the Ascomycete Yeasts

    SciTech Connect

    Riley, Robert; Haridas, Sajeet; Salamov, Asaf; Boundy-Mills, Kyria; Goker, Markus; Hittinger, Chris; Klenk, Hans-Peter; Lopes, Mariana; Meir-Kolthoff, Jan P.; Rokas, Antonis; Rosa, Carlos; Scheuner, Carmen; Soares, Marco; Stielow, Benjamin; Wisecaver, Jennifer H.; Wolfe, Ken; Blackwell, Meredith; Kurtzman, Cletus; Grigoriev, Igor; Jeffries, Thomas

    2015-03-16

    Yeasts are important for industrial and biotechnological processes and show remarkable metabolic and phylogenetic diversity despite morphological similarities. We have sequenced the genomes of 16 ascomycete yeasts of taxonomic and industrial importance including members of Saccharomycotina and Taphrinomycotina. Phylogenetic analysis of these and previously published yeast genomes helped resolve the placement of species including Saitoella complicata, Babjeviella inositovora, Hyphopichia burtonii, and Metschnikowia bicuspidata. Moreover, we find that alternative nuclear codon usage, where CUG encodes serine instead of leucine, are monophyletic within the Saccharomycotina. Most of the yeasts have compact genomes with a large fraction of single exon genes, and a tendency towards more introns in early-diverging species. Analysis of enzyme phylogeny gives insights into the evolution of metabolic capabilities such as methanol utilization and assimilation of alternative carbon sources.

  11. A mushroom lectin from ascomycete Cordyceps militaris.

    PubMed

    Jung, Eui Cha; Kim, Ki Don; Bae, Chan Hyung; Kim, Ju Cheol; Kim, Dae Kyong; Kim, Ha Hyung

    2007-05-01

    A mushroom lectin has been purified from ascomycete Cordyceps militaris, which is one of the most popular mushrooms in eastern Asia used as a nutraceutical and in traditional Chinese medicine. This lectin, designated CML, exhibited hemagglutination activity in mouse and rat erythrocytes, but not in human ABO erythrocytes. SDS-PAGE of CML revealed a single band with a molecular mass of 31.0 kDa under both nonreducing and reducing conditions that was stained by silver nitrate, and a 31.4 kDa peak in a Superdex-200 HR gel-filtration column. The hemagglutination activity was inhibited by sialoglycoproteins, but not in by mono- or disaccharides, asialoglycoproteins, or de-O-acetylated glycoprotein. The activity was maximal at pH 6.0-9.1 and at temperatures below 50 degrees C. Circular dichroism spectrum analysis revealed that CML comprises 27% alpha-helix, 12% beta-sheets, 29% beta-turns, and 32% random coils. Its binding specificity and secondary structure are similar to those of a fungal lectin from Arthrobotrys oligospora. However, the N-terminal amino acid sequence of CML differs greatly from those of other lectins. CML exhibits mitogenic activity against mouse splenocytes. PMID:17306462

  12. Interactive effects of pollination and heavy metals on resource allocation in Potentilla anserina L.

    SciTech Connect

    Saikkonen, K. |; Koivunen, S.; Vuorisalo, T.; Mutikainen, P. |

    1998-07-01

    The authors studied resource allocation between sexual reproduction and clonal propagation in a perennial stoloniferous clonal plant, Potentilla anserina, an obligate outcrosser. They manipulated reproductive effort of Potentilla anserina either by hand-pollinating all flowers or by preventing pollination. To test the effect of resource-limiting conditions on resource allocation and reproductive output, the authors used a control and two levels of heavy metals (copper and nickel) to limit plant growth. The experiment was conducted as a 2 {times} 3 factorial design to reveal possible interactions between reproductive manipulation and resource limitation. Heavy metals decreased the total biomass of the plants and number of flowers and ramets produced. Only 50% of the plants grown with the higher level of heavy metals produced flowers. Pollination treatment interacted significantly with the heavy-metal treatment. In the metal control and lower heavy-metal treatment, there were no significant differences in total vegetative biomass between the two pollination treatments. Costs of reproduction in terms of subsequent flowering in the later season appeared to be clear, because the number of flowers per whole plant was lower if the plants were hand-pollinated and because the proportion of flowering ramets decreased due to hand-pollination. However, flowering may also be partly hormonally controlled. In contrast, hand-pollinated plants exposed to high concentrations of heavy metals tended to have greater biomass of vegetative plant structures and higher number of flowers compared to nonpollinated plants.

  13. Basidiomycete yeasts in the cortex of ascomycete macrolichens.

    PubMed

    Spribille, Toby; Tuovinen, Veera; Resl, Philipp; Vanderpool, Dan; Wolinski, Heimo; Aime, M Catherine; Schneider, Kevin; Stabentheiner, Edith; Toome-Heller, Merje; Thor, Göran; Mayrhofer, Helmut; Johannesson, Hanna; McCutcheon, John P

    2016-07-29

    For over 140 years, lichens have been regarded as a symbiosis between a single fungus, usually an ascomycete, and a photosynthesizing partner. Other fungi have long been known to occur as occasional parasites or endophytes, but the one lichen-one fungus paradigm has seldom been questioned. Here we show that many common lichens are composed of the known ascomycete, the photosynthesizing partner, and, unexpectedly, specific basidiomycete yeasts. These yeasts are embedded in the cortex, and their abundance correlates with previously unexplained variations in phenotype. Basidiomycete lineages maintain close associations with specific lichen species over large geographical distances and have been found on six continents. The structurally important lichen cortex, long treated as a zone of differentiated ascomycete cells, appears to consistently contain two unrelated fungi. PMID:27445309

  14. Discussion of teleomorphic and anamorphic Ascomycetous yeasts and yeast-like taxa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The relationship of ascomycetous yeasts with other members of the ascomycete fungi (Ascomycota) has been controversial for over 100 years. Because yeasts are morphologically simple, it was proposed that they represent primitive forms of ascomycetes (e.g., Guilliermond 1912). Alternatively, the ide...

  15. NOTES ON ASCOMYCETE SYSTEMATICS NOS 3303-3579

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The series "Notes on ascomycete systematics" has been published in Systema Ascomycetum (Eriksson & Hawksworth 1986-1998) and since 1999 in Myconet in an electronic version on the Internet (http://www.umu.se/myconet/notes.html) and as hard copies once or twice a year in a journal with the same name (...

  16. Antifungal Susceptibility Testing of Ascomycetous Yeasts Isolated from Animals.

    PubMed

    Álvarez-Pérez, Sergio; García, Marta E; Peláez, Teresa; Martínez-Nevado, Eva; Blanco, José L

    2016-08-01

    Recent studies suggest that antifungal resistance in yeast isolates of veterinary origin may be an underdiagnosed threat. We tested a collection of 92 ascomycetous yeast isolates that were obtained in Spain from birds, mammals and insects for antifungal susceptibility. MICs to amphotericin B and azoles were low, and no resistant isolates were detected. Despite these results, and given the potential role of animals as reservoirs of resistant strains, continuous monitoring of antifungal susceptibility in the veterinary setting is recommended. PMID:27216048

  17. Specific Antibodies Reactive with the 22-Kilodalton Major Outer Surface Protein of Borrelia anserina Ni-NL Protect Chicks from Infection

    PubMed Central

    Sambri, Vittorio; Marangoni, Antonella; Olmo, Andrea; Storni, Elisa; Montagnani, Marco; Fabbi, Massimo; Cevenini, Roberto

    1999-01-01

    An outer surface lipoprotein of 22 kDa was identified in the avian pathogen Borrelia anserina Ni-NL by using antibody preparations reactive with bacterial surface-exposed proteins. Amino acid sequence analysis of the 22-kDa protein demonstrated 90% identity with VmpA of B. turicatae, suggesting that the protein belongs to the family of 20-kDa outer surface proteins of the genus Borrelia. All of the 60 chicks intramuscularly treated with antibodies specifically reacting with the 22-kDa protein and infected with strain Ni-NL were completely protected from infection, since no spirochetemia was detected, and from death. Control chicks were treated with immune sera raised against apathogenic strain B. anserina Es, which expresses a prominent 20-kDa polypeptide that is also a member of the Vmp family but does not cross-react immunologically with the 22-kDa protein of the Ni-NL strain. These animals, infected with B. anserina Ni-NL, showed a high degree of spirochetemia 10 days after infection, and all died between 14 and 21 days after infection. The results showed that the 22-kDa surface protein of B. anserina Ni-NL is a determinant of the pathogenic potential of the strain and also confirmed that only strain-specific antibodies are protective against B. anserina infection. PMID:10225933

  18. Genomics of alternative sulfur utilization in ascomycetous yeasts.

    PubMed

    Linder, Tomas

    2012-10-01

    Thirteen ascomycetous yeast strains with sequenced genomes were assayed for their ability to grow on chemically defined medium with 16 different sulfur compounds as the only significant source of sulfur. These compounds included sulfoxides, sulfones, sulfonates, sulfamates and sulfate esters. Broad utilization of alternative sulfur sources was observed in Komagataella pastoris (syn. Pichia pastoris), Lodderomyces elongisporus, Millerozyma farinosa (syn. Pichia sorbitophila), Pachysolen tannophilus, Scheffersomyces stipitis (syn. Pichia stipitis), Spathaspora passalidarum, Yamadazyma tenuis (syn. Candida tenuis) and Yarrowia lipolytica. Kluyveromyces lactis, Saccharomyces cerevisiae and Zygosaccharomyces rouxii were mainly able to utilize sulfonates and sulfate esters, while Lachancea thermotolerans and Schizosaccharomyces pombe were limited to aromatic sulfate esters. Genome analysis identified several candidate genes with bacterial homologues that had been previously shown to be involved in the utilization of alternative sulfur sources. Analysis of candidate gene promoter sequences revealed a significant overrepresentation of DNA motifs that have been shown to regulate sulfur metabolism in Sacc. cerevisiae. PMID:22790398

  19. Identification of Oxaphenalenone Ketals from the Ascomycete Fungus Neonectria sp.

    PubMed

    Ren, Jinwei; Niu, Shubing; Li, Li; Geng, Zhufeng; Liu, Xingzhong; Che, Yongsheng

    2015-06-26

    Neonectrolides B-E (4-7), four new oxaphenalenone ketals incorporating the new furo[2,3-b]isochromeno[3,4,5-def]chromen-11(6aH)-one skeleton, were isolated from the fermentation extract of the ascomycete fungus Neonectria sp. in an in-depth investigation guided by HPLC fingerprint and a cytotoxicity assay. The previously identified oxaphenalenone spiroketal neonectrolide A (1) and its putative biosynthetic precursors (2 and 3) were also reisolated in the current work. The structures of 4-7 were primarily elucidated by interpretation of NMR spectroscopic data, and the absolute configurations were deduced by electronic circular dichroism calculations. Compound 6 showed cytotoxic effects against four of the six human tumor cell lines tested. Biosynthetically, compounds 4-7 could be derived via the Diels-Alder reaction cascades starting from derivatives of the co-isolated metabolites 2 and 3. PMID:25978132

  20. The Chemical Diversity of the Ascomycete Fungus Paecilomyces variotii.

    PubMed

    Mioso, Roberto; Toledo Marante, Francisco Javier; Herrera Bravo de Laguna, Irma

    2015-10-01

    Paecilomyces variotii isolated from a broad range of habitats drives the diversification of new high-value-added secondary metabolites that could potentially play an important role in human and animal health. These metabolites include the anhydride metabolite of the nonadride family, as well as the following compounds: naphthopyranone metabolites, sphingofungins, eicosenoic acids, new branched fatty acids, ascofuranone, polyketides, an anacardic acid analogue, straight-chain peptides, and volatile compounds. These natural products show that P. variotii can provide leading compounds for new drug discoveries, which may include herbicide agents, some of which are important in the agrochemical market. Finally, this review outlines recent developments, trends, and prospects for the chemistry of this ascomycete. PMID:26288080

  1. [Study of the antigenic makeup of strains of Borrelia anserina, Sakharoff, 1891, of the Surnevo and Pamoukchii serotypes].

    PubMed

    Dzhankov, I; Sumrov, I; Lozeva, T

    1975-01-01

    An antigen analysis of Borrelia anserina strains, belonging to two serotypes, was carried out for the first time by means of direct immunofluorescence microscopy, gel diffusion after Ouchterlony, immunoelectrophoresis as modified by Scheidegger, and whole serum macroagglutination reaction. It was found that the spirochetes of the strain Rouen of Pamoukchii serotype possess eight surface antigens, and those of strain Surnevo I of the same serotype have 6. The two strains were found to have as many as four common surface antigens, on the one hand, and two type-specific antigens each, on the other. Strain Rouen has a heat-resistant type-specific antigen, probably of a polysaccharide nature. Two of the surface antigens of strain Rouen were found to be more deeply bound in strain Surnevo I. PMID:814698

  2. Phylogenetic studies of four Anser cygnoides (Anserini: Anserinae) in Hunan province of China based on complete mitochondrial DNA sequences.

    PubMed

    Dai, Qiu-Zhong; Lin, Qian; Jiang, Gui-Tao

    2016-07-01

    In this study, we cloned and sequenced the complete mitochondrial DNAs of Chinese goose, Anser cygnoides populations from three different areas of Hunan province in China. The Anser cygnoides breed Wugangtong white goose (WGTW) sample and Wugangtong grey goose sample (WGTG) were taken from the Wugang county of Shaoyang city, the Anser cygnoides breed Xupu goose (XP) sample was taken from the Xupu county of Huaihua city, and the Anser cygnoides breed Yanling white goose (YLW) sample was taken from the Yanling county of Zhuzhou city. The organization of the four Anser cygnoides breeds mitochondrial genomes was similar. Phylogenetic analyses using N-J computational algorithms showed that the analyzed species are divided into four major clades: Anatinae, Anserinae, Dendrocygninae and Anseranatidae. It was noted that Wugangtong white goose, Yanling white goose and Xupu goose have highly similar phylogenetic relationship. PMID:26057006

  3. Botryane, noreudesmane and abietane terpenoids from the ascomycete Hypoxylon rickii.

    PubMed

    Kuhnert, Eric; Surup, Frank; Wiebach, Vincent; Bernecker, Steffen; Stadler, Marc

    2015-09-01

    In the course of our screening for new bioactive natural products, a culture of Hypoxylon rickii, a xylariaceous ascomycete collected from the Caribbean island Martinique, was identified as extraordinary prolific producer of secondary metabolites. Ten metabolites of terpenoid origin were isolated from submerged cultures of this species by preparative HPLC. Their structures were elucidated using spectral techniques including 2D NMR and HRESIMS. Three of the compounds were elucidated as new botryanes (1-3) along with three known ones, i.e. (3aS)-3a,5,5,8-tetramethyl-3,3a,4,5-tetrahydro-1H-cyclopenta[de]isochromen-1-one (4), (3aS,8R)-3a,5,5,8-tetramethyl-3,3a,4,5,7,8-hexahydro-1H-cyclopenta[de]isochromen-1-one (5) and botryenanol (6). Further three new sesquiterpenoids featured a 14-noreudesmane-type skeleton and were named hypoxylan A-C (7-9); the diterpenoid rickitin A (10) contains an abietane-type backbone. Compounds 1, 2, 3, 7, and 10 showed cytotoxic effects against murine cells. PMID:26071840

  4. Halide uptake by the filamentous ascomycete Neocosmospora vasinfecta.

    PubMed Central

    Miller, A G; Budd, K

    1975-01-01

    The uptake of Cl minus by the ascomycetes Neocosmospora vasinfecta was investigated. Intramycelial concentrations of more than 55 mM (890-fold the external concentration) were reached. Accumulation was as inorganic Cl minus and nystatin induced total loss of mycelial Cl minus without extensive protein loss, implying that Cl minus retention was not due to binding to macromolecules. Cl minus transport was largely unidirectional with efflux being low under all conditions. Uptake was temperature dependent (maximal Arrhenius activation energy of 18.0 kcal/mol) and was severely reduced by KCN, dicyclohexylcarbodiimide, and anaerobiosis. A comparison with the inhibition of oxygen uptake under the same conditions implied that Cl minus transport was not directly coupled to aerobic electron transport. Cl minus uptake was a saturatable function of the external Cl minus concentration, and apparent Km values of 6.4 times 10-6 M and 10-4 M were calculated. Of the anions tested, only Br minus effectively inhibited Cl minus uptake and I minus, NO3 minus, SO4 minus 2, HCO3 minus, and H2PO4 minus were without effect. Cl minus uptake did not require concomitant cation uptake. PMID:234943

  5. Common amino acid domain among endopolygalacturonases of ascomycete fungi.

    PubMed Central

    Keon, J P; Waksman, G

    1990-01-01

    The endopolygalacturonase (EC 3.2.1.15) enzymes produced in vitro by three ascomycete fungi, Aspergillus niger, Sclerotinia sclerotiorum, and Colletotrichum lindemuthianum were studied by using thin-layer isoelectric focusing and activity stain overlay techniques. The polygalacturonases from A. niger and S. sclerotiorum consisted of numerous isoforms, whereas the endopolygalacturonase from C. lindemuthianum consisted of a single protein species. The most abundant endopolygalacturonase isoform produced by each of these organisms was purified and characterized. Biochemical parameters, including molecular weight, isoelectric point, kinetic parameters, temperature and pH optima, and thermal stability, were determined. Considerable differences in physical and chemical properties were demonstrated among these fungal polygalacturonases. Antibodies raised against individual proteins exhibited little cross-reaction, suggesting that these enzymes differ structurally as well as biochemically. In contrast, the analysis of the N-terminal amino acid sequences of the three proteins showed extensive homology, particularly in a region labeled domain 1 in which 84% of the amino acids were conserved. Images PMID:2403258

  6. Mycelial pellet formation by edible ascomycete filamentous fungi, Neurospora intermedia.

    PubMed

    Nair, Ramkumar B; Lennartsson, Patrik R; Taherzadeh, Mohammad J

    2016-12-01

    Pellet formation of filamentous fungi in submerged culture is an imperative topic of fermentation research. In this study, we report for the first time the growth of filamentous ascomycete fungus, Neurospora intermedia in its mycelial pellet form. In submerged culture, the growth morphology of the fungus was successfully manipulated into growing as pellets by modifying various cultivation conditions. Factors such as pH (2.0-10.0), agitation rate (100-150 rpm), carbon source (glucose, arabinose, sucrose, and galactose), the presence of additive agents (glycerol and calcium chloride) and trace metals were investigated for their effect on the pellet formation. Of the various factors screened, uniform pellets were formed only at pH range 3.0-4.0, signifying it as the most influential factor for N. intermedia pellet formation. The average pellet size ranged from 2.38 ± 0.12 to 2.86 ± 0.38 mm. The pellet formation remained unaffected by the inoculum type used and its size showed an inverse correlation with the agitation rate of the culture. Efficient glucose utilization was observed with fungal pellets, as opposed to the freely suspended mycelium, proving its viability for fast-fermentation processes. Scale up of the pelletization process was also carried out in bench-scale airlift and bubble column reactors (4.5 L). PMID:27103628

  7. Lipids stimulate spore germination in the entomopathogenic ascomycete Ascosphaera aggregata.

    PubMed

    James, R R; Buckner, J S

    2004-10-01

    The alfalfa leafcutting bee (Megachile rotundata) is solitary and managed on a large scale for pollination of alfalfa seed crops. The bees nest in holes drilled in wood or polystyrene blocks, and their larvae are highly prone to a fungal disease called chalkbrood. The most prevalent form of chalkbrood is caused by Ascosphaera aggregata, but this ascomycete is difficult to culture. Hyphae will grow on standard fungal media, but spore germination is difficult to achieve and highly variable. We found that germination can be enhanced with oils. Lipids derived from plants and bee larvae increased germination from 50% (without oil) to 75-85% (with oil). Percent germination was significantly greater in the presence of lipids but germination was not significantly different when different oils, including mineral oil, were used. A. aggregata spores oriented along the oil-aqueous interface in the broth in a polar fashion, with swelling and germ tube formation always occurring into the aqueous portion of the broth. The other half of the spore tended to attach to a lipid droplet, where it remained, without swelling, during germ tube formation. The physical attachment of spores to the oil-aqueous interface is what most probably stimulates spore germination, as opposed to some nutritional stimulation. However, further research is needed to determine if and where the spores encounter such an interface when germinating in the host gut, where germination normally occurs. PMID:15645171

  8. Production of sordarin and related metabolites by the coprophilous fungus Podospora pleiospora in submerged culture and in its natural substrate.

    PubMed

    Weber, Roland W S; Meffert, Anja; Anke, Heidrun; Sterner, Olov

    2005-05-01

    Rabbit pellets collected from the field were colonized by Podospora pleiospora at the exclusion of other coprophilous fungi, suggesting antibiosis. In liquid culture, P. pleiospora produced sordarin (1); sordarin B (2), a new compound in which sordarose is replaced by rhamnose; hydroxysordarin (3); and sordaricin (4). The major compounds 1 and 2 exhibited minimum inhibitory concentrations of 0.5-2.5 microg ml(-1) against the yeasts Nematospora coryli and Sporobolomyces roseus, but showed little or no activity against bacteria or coprophilous filamentous fungi. In liquid culture, the production of 1 and 2 together amounted to 2.7 microg ml(-1), whereas in rabbit dung only 1 was produced at a similar concentration (2.3 microg g(-1) fresh weight). The biosynthesis of these substances was unaffected by the presence of inoculum of other fungi tested (Sporobolomyces roseus or Penicillium claviforme) in liquid culture or on dung. Sordarin-type natural products are therefore synthesized by P. pleiospora at sufficiently high concentrations to account for antibiosis against yeasts, but not against filamentous fungi. PMID:16018317

  9. Quantifying functional heterothallism in the pseudohomothallic ascomycete Neurospora tetrasperma.

    PubMed

    Corcoran, Pádraic; Jacobson, David J; Bidartondo, Martin I; Hickey, Patrick C; Kerekes, Jennifer F; Taylor, John W; Johannesson, Hanna

    2012-09-01

    Neurospora tetrasperma is a pseudohomothallic filamentous ascomycete that has evolved from heterothallic ancestors. Throughout its life cycle, it is predominantly heterokaryotic for mating type, and thereby self-fertile. However, studies of N. tetrasperma have revealed the occasional production of self-sterile asexual and sexual spores of a single-mating type, indicating that it can be functionally heterothallic. Here, we report the extensive sampling and isolation of natural, heterokaryotic, strains of N. tetrasperma from the United Kingdom (UK): 99 strains were collected from Surrey, England, and four from Edinburgh, Scotland. We verified by phylogenetic analyses that these strains belong to N. tetrasperma. We isolated cultures from single germinated asexual spores (conidia) from 17 of these newly sampled UK strains from Surrey, and 16 previously sampled strains of N. tetrasperma from New Zealand (NZ). Our results show that the N. tetrasperma strains from the UK population produced a significantly greater proportion of self-sterile, homokaryotic conidia than the NZ population: the proportion of homokaryotic conidia was 42.6 % (133/312 spores) and 15.3 % (59/386) from the UK and the NZ populations, respectively. Although homokaryons recovered from several strains show a bias for one of the mating types, the total ratio of mat A to mat a mating type in homokaryons (UK: 72/61, NZ 28/31) did not deviate significantly from the expected 1:1 ratio for either of these populations. These results indicate that different populations exhibit differences in their life cycle characteristics, and that a higher degree of outcrossing might be expected from the UK population. This study points to the importance of studying multiple strains and populations when investigating life history traits of an organism with a complex life cycle, as previously undetected differences between populations may be revealed. PMID:22954339

  10. Phylogeny of the ascomycetous yeasts and the renaming of Pichia anomala to Wickerhamomyces anomalus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pichia anomala was reclassified as Wickerhamomyces anomalus following multigene phylogenetic analysis. In this review, the phylogeny of the ascomycetous yeasts is discussed, with emphasis on the genus Pichia. The genus, as defined from phenotype, had nearly 100 assigned species, but the number of ...

  11. Low pH dye decolorization with ascomycete Lamprospora wrightii laccase.

    PubMed

    Mueangtoom, Kitti; Kittl, Roman; Mann, Oliver; Haltrich, Dietmar; Ludwig, Roland

    2010-08-01

    In a screening of saprotrophic, ectomycorrhizal and plant pathogen ascomycetes a frequent occurrence of laccase was observed. Lamprospora wrightii, the best producing organism, was chosen to elucidate the properties of a laccase from a moss-associated, saprotrophic ascomycete. The expression of laccase by this bryophilic fungus could be increased by the addition of tomato juice or copper sulfate to the medium. The obtained volumetric activity after optimization was 420 U/mL in either shaking flask or bioreactor-based cultivations. The purified laccase has a molecular mass of 68 kDa and an isoelectric point of 3.4. Although of ascomycete origin, its catalytic properties are similar to typical basidiomycte laccases, and an excellent activity and stability was observed at low pH, which makes it suitable for bioremediation in acidic environments. As an example, the decolorization reactions of azo-, anthraquinone-, trimethylmethane- and indigoid dyes at pH 3.0 and 5.0 were investigated. All ten selected dyes were decolorized, five of them very efficiently. Depending on the dye, the decolorization was found to be a combination of two reactions, degradation of the chromophore and formation of polymerized products, which contributed to the overall process in a dye-specific pattern. PMID:20652905

  12. Ascomycetes associated with ectomycorrhizas: molecular diversity and ecology with particular reference to the Helotiales.

    PubMed

    Tedersoo, Leho; Pärtel, Kadri; Jairus, Teele; Gates, Genevieve; Põldmaa, Kadri; Tamm, Heidi

    2009-12-01

    Mycorrhizosphere microbes enhance functioning of the plant-soil interface, but little is known of their ecology. This study aims to characterize the ascomycete communities associated with ectomycorrhizas in two Tasmanian wet sclerophyll forests. We hypothesize that both the phyto- and mycobiont, mantle type, soil microbiotope and geographical distance affect the diversity and occurrence of the associated ascomycetes. Using the culture-independent rDNA sequence analysis, we demonstrate a high diversity of these fungi on different hosts and habitats. Plant host has the strongest effect on the occurrence of the dominant species and community composition of ectomycorrhiza-associated fungi. Root endophytes, soil saprobes, myco-, phyto- and entomopathogens contribute to the ectomycorrhiza-associated ascomycete community. Taxonomically these Ascomycota mostly belong to the orders Helotiales, Hypocreales, Chaetothyriales and Sordariales. Members of Helotiales from both Tasmania and the Northern Hemisphere are phylogenetically closely related to root endophytes and ericoid mycorrhizal fungi, suggesting their strong ecological and evolutionary links. Ectomycorrhizal mycobionts from Australia and the Northern Hemisphere are taxonomically unrelated to each other and phylogenetically distant to other helotialean root-associated fungi, indicating independent evolution. The ubiquity and diversity of the secondary root-associated fungi should be considered in studies of mycorrhizal communities to avoid overestimating the richness of true symbionts. PMID:19671076

  13. Role of Reactive Intermediates in Manganese Oxide Formation By Filamentous Ascomycete Fungi

    NASA Astrophysics Data System (ADS)

    Zeiner, C. A.; Anderton, C.; Wu, S.; Purvine, S.; Zink, E.; Paša-Tolić, L.; Santelli, C. M.; Hansel, C. M.

    2014-12-01

    Biogenic manganese (Mn) oxide minerals are ubiquitous in the environment, and their high reactivity can profoundly impact the fate of contaminants and cycling of carbon and nutrients. In contrast to bacteria, the pathways utilized by fungi to oxidize Mn(II) to Mn(III,IV) oxides remain largely unknown. Here, we explore the mechanisms of Mn(II) oxidation by a phylogenetically diverse group of filamentous Ascomycete fungi using a combination of chemical assays and bulk and spatially-resolved mass spectrometry. We show that the mechanisms of Mn(II) oxidation vary with fungal species, over time during secretome compositional changes, and in the presence of other fungi. Specifically, our work implicates a dynamic transition in Mn(II) oxidation pathways that varies between species. In particular, while reactive oxygen species (ROS) produced via transmembrane NADPH oxidases are involved in initial oxidation, over time, secreted enzymes become important Mn(II) oxidation mediators for some species. In addition, the overall secretome oxidation capacity varies with time and fungal species. Secretome analysis reveals a surprising absence of enzymes currently considered to be Mn(II)-oxidizing enzymes in these organisms, and instead highlights a wide variety of redox-active enzymes. Furthermore, we implicate fungal cell defense mechanisms in the formation of distinct Mn oxide patterns when fungi are grown in head-to-head competition. The identification and regulation of these secreted enzymes are under current investigation within the bulk secretome and within the interaction zone of structured fungal communities. Overall, our findings illustrate that Ascomycete Mn(II) oxidation mechanisms are highly variable and are dictated by complex environmental and ecological interactions. Future work will explore the connection between Ascomycete Mn(II) oxidation and the ability to degrade cellulose, a key carbon reservoir for biofuel production.

  14. SHARED ITS DNA SUBSTITUTIONS IN ISOLATES OF OPPOSITE MATING TYPE REVEAL A RECOMBIING HISTORY FOR THREE PRESUMED ASEXUAL SPECIES IN THE FILAMENTOUS ASCOMYCETE GENUS ALTERNARIA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    About 15,000 species of ascomycete fungi lack a known sexual state. For fungi with asexual states in the form genera Embellisia, Ulocladium and Alternaria, six species have known sexual states but more than 50 species do not. In sexual filamentous ascomycetes, opposite mating type information at t...

  15. Explosively launched spores of ascomycete fungi have drag-minimizing shapes.

    PubMed

    Roper, Marcus; Pepper, Rachel E; Brenner, Michael P; Pringle, Anne

    2008-12-30

    The forcibly launched spores of ascomycete fungi must eject through several millimeters of nearly still air surrounding fruiting bodies to reach dispersive air flows. Because of their microscopic size, spores experience great fluid drag, and although this drag can aid transport by slowing sedimentation out of dispersive air flows, it also causes spores to decelerate rapidly after launch. We hypothesize that spores are shaped to maximize their range in the nearly still air surrounding fruiting bodies. To test this hypothesis we numerically calculate optimal spore shapes-shapes of minimum drag for prescribed volumes-and compare these shapes with real spore shapes taken from a phylogeny of >100 species. Our analysis shows that spores are constrained to remain within 1% of the minimum possible drag for their size. From the spore shapes we predict the speed of spore launch, and confirm this prediction through high-speed imaging of ejection in Neurospora tetrasperma. By reconstructing the evolutionary history of spore shapes within a single ascomycete family we measure the relative contributions of drag minimization and other shape determinants to spore shape evolution. Our study uses biomechanical optimization as an organizing principle for explaining shape in a mega-diverse group of species and provides a framework for future measurements of the forces of selection toward physical optima. PMID:19104035

  16. Conservation and Evolution of Cis-Regulatory Systems in Ascomycete Fungi

    PubMed Central

    2004-01-01

    Relatively little is known about the mechanisms through which gene expression regulation evolves. To investigate this, we systematically explored the conservation of regulatory networks in fungi by examining the cis-regulatory elements that govern the expression of coregulated genes. We first identified groups of coregulated Saccharomyces cerevisiae genes enriched for genes with known upstream or downstream cis-regulatory sequences. Reasoning that many of these gene groups are coregulated in related species as well, we performed similar analyses on orthologs of coregulated S. cerevisiae genes in 13 other ascomycete species. We find that many species-specific gene groups are enriched for the same flanking regulatory sequences as those found in the orthologous gene groups from S. cerevisiae, indicating that those regulatory systems have been conserved in multiple ascomycete species. In addition to these clear cases of regulatory conservation, we find examples of cis-element evolution that suggest multiple modes of regulatory diversification, including alterations in transcription factor-binding specificity, incorporation of new gene targets into an existing regulatory system, and cooption of regulatory systems to control a different set of genes. We investigated one example in greater detail by measuring the in vitro activity of the S. cerevisiae transcription factor Rpn4p and its orthologs from Candida albicans and Neurospora crassa. Our results suggest that the DNA binding specificity of these proteins has coevolved with the sequences found upstream of the Rpn4p target genes and suggest that Rpn4p has a different function in N. crassa. PMID:15534694

  17. Conservation and evolution of cis-regulatory systems in ascomycete fungi

    SciTech Connect

    Gasch, Audrey P.; Moses, Alan M.; Chiang, Derek Y.; Fraser, Hunter B.; Berardini, Mark; Eisen, Michael B.

    2004-03-15

    Relatively little is known about the mechanisms through which gene expression regulation evolves. To investigate this, we systematically explored the conservation of regulatory networks in fungi by examining the cis-regulatory elements that govern the expression of coregulated genes. We first identified groups of coregulated Saccharomyces cerevisiae genes enriched for genes with known upstream or downstream cis-regulatory sequences. Reasoning that many of these gene groups are coregulated in related species as well, we performed similar analyses on orthologs of coregulated S. cerevisiae genes in 13 other ascomycete species. We find that many species-specific gene groups are enriched for the same flanking regulatory sequences as those found in the orthologous gene groups from S. cerevisiae, indicating that those regulatory systems have been conserved in multiple ascomycete species. In addition to these clear cases of regulatory conservation, we find examples of cis-element evolution that suggest multiple modes of regulatory diversification, including alterations in transcription factor-binding specificity, incorporation of new gene targets into an existing regulatory system, and cooption of regulatory systems to control a different set of genes. We investigated one example in greater detail by measuring the in vitro activity of the S. cerevisiae transcription factor Rpn4p and its orthologs from Candida albicans and Neurospora crassa. Our results suggest that the DNA binding specificity of these proteins has coevolved with the sequences found upstream of the Rpn4p target genes and suggest that Rpn4p has a different function in N. crassa.

  18. Autochthonous ascomycetes in depollution of polychlorinated biphenyls contaminated soil and sediment.

    PubMed

    Sage, Lucile; Périgon, Sophie; Faure, Mathieu; Gaignaire, Carole; Abdelghafour, Mohamed; Mehu, Jacques; Geremia, Roberto A; Mouhamadou, Bello

    2014-09-01

    We investigated the capacity of a consortium of ascomycetous strains, Doratomyces nanus, Doratomyces purpureofuscus, Doratomyces verrucisporus, Myceliophthora thermophila, Phoma eupyrena and Thermoascus crustaceus in the mycoremediation of historically contaminated soil and sediment by polychlorinated biphenyls (PCBs). Analyses of 15 PCB concentrations in three mesocosms containing soil from which the fungal strains had previously been isolated, revealed significant PCB depletions of 16.9% for the 6 indicator PCBs (i-PCBs) and 18.7% for the total 15 PCBs analyzed after 6months treatment. The degradation rate did not statistically vary whether the soil had been treated with non-inoculated straw or colonized straw or without straw and inoculated with the consortium of the six strains. Concerning the sediment, we evidenced significant depletions of 31.8% for the 6 i-PCBs and 33.3% for the 15 PCB congeners. The PCB depletions affected most of the 15 PCBs analyzed without preference for lower chlorinated congeners. Bioaugmented strains were evidenced in different mesocosms, but their reintroduction, after six months treatment, did not improve the rate of PCB degradation, suggesting that the biodegradation could affect the bioavailable PCB fraction. Our results demonstrate that the ascomycetous strains potentially adapted to PCBs may be propitious to the remediation of PCB contaminated sites. PMID:24880600

  19. LIGNOCELLULOSE-DEGRADING ENZYMES PRODUCED BY THE ASCOMYCETE CONIOCHAETA LIGNIARIA AND RELATED SPECIES: APPLICATION FOR A LIGNOCELLULOSIC SUBSTRATE TREATMENT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lignocellulose-degrading microorganisms are of interest for biomass upgrading. In previous work, we isolated the ascomycete Coniochaeta ligniaria NRRL 30616 that metabolized phenolics and furans in lignocellulosic acid hydrolysates. This fungal isolate was investigated in the present work for the ...

  20. Waste biorefineries using filamentous ascomycetes fungi: Present status and future prospects.

    PubMed

    Ferreira, Jorge A; Mahboubi, Amir; Lennartsson, Patrik R; Taherzadeh, Mohammad J

    2016-09-01

    Filamentous ascomycetes fungi have had important roles in natural cycles, and are already used industrially for e.g. supplying of citric, gluconic and itaconic acids as well as many enzymes. Faster human activities result in higher consumption of our resources and producing more wastes. Therefore, these fungi can be explored to use their capabilities to convert back wastes to resources. The present paper reviews the capabilities of these fungi in growing on various residuals, producing lignocellulose-degrading enzymes and production of organic acids, ethanol, pigments, etc. Particular attention has been on Aspergillus, Fusarium, Neurospora and Monascus genera. Since various species are used for production of human food, their biomass can be considered for feed applications and so biomass compositional characteristics as well as aspects related to culture in bioreactor are also provided. The review has been further complemented with future research avenues. PMID:26996263

  1. Freshwater ascomycetes: Alascospora evergladensis, a new genus and species from the Florida Everglades.

    PubMed

    Raja, Huzefa A; Violi, Helen A; Shearer, Carol A

    2010-01-01

    Alascospora evergladensis, a freshwater ascomycete collected from submerged dead petioles of Nymphaea odorata during a survey of aquatic fungi along a phosphorus gradient in the Florida Everglades, is described and illustrated as a new genus and species in the Pleosporales (Pleosporomycetidae, Dothideomycetes). The new fungus is unique among genera in the Pleosporales based on a combination of morphological characters that include light brown, translucent, membranous, ostiolate ascomata with dark, amorphous material irregularly deposited on the peridium, especially around the ostiole; globose, fissitunicate, thick-walled asci; septate pseudoparaphyses; and 1-septate ascospores that are hyaline when young, and surrounded by a hyaline gelatinous sheath that is wing-shaped in outline on each side of the ascospore. The sheath is distinctive in that it first expands in water and is translucent, then condenses and darkens around older ascospores, giving them a dark brown, verruculose appearance. PMID:20120226

  2. Genome mining of ascomycetous fungi reveals their genetic potential for ergot alkaloid production.

    PubMed

    Gerhards, Nina; Matuschek, Marco; Wallwey, Christiane; Li, Shu-Ming

    2015-06-01

    Ergot alkaloids are important as mycotoxins or as drugs. Naturally occurring ergot alkaloids as well as their semisynthetic derivatives have been used as pharmaceuticals in modern medicine for decades. We identified 196 putative ergot alkaloid biosynthetic genes belonging to at least 31 putative gene clusters in 31 fungal species by genome mining of the 360 available genome sequences of ascomycetous fungi with known proteins. Detailed analysis showed that these fungi belong to the families Aspergillaceae, Clavicipitaceae, Arthrodermataceae, Helotiaceae and Thermoascaceae. Within the identified families, only a small number of taxa are represented. Literature search revealed a large diversity of ergot alkaloid structures in different fungi of the phylum Ascomycota. However, ergot alkaloid accumulation was only observed in 15 of the sequenced species. Therefore, this study provides genetic basis for further study on ergot alkaloid production in the sequenced strains. PMID:25796201

  3. Bioconversion of (+)-valencene in submerged cultures of the ascomycete Chaetomium globosum.

    PubMed

    Kaspera, Rüdiger; Krings, Ulrich; Nanzad, Tsevegsuren; Berger, Ralf G

    2005-06-01

    Submerged cultures of the ascomycete Chaetomium globosum oxidised the exogenous sesquiterpene (+)-valencene to nootkatone via the stereoselective generation of alpha-nootkatol. Inhibition experiments suggested that the first introduction of oxygen, the rate-limiting step of the bioconversion, may have been catalysed by a cytochrome-P450-monooxygenase. However, nootkatone was not the final metabolite: further flavour-active and inactive, non-volatile oxidation products were identified. (+)-Valencene and the flavour-active mono-oxyfunctionalised transformation products, alpha-nootkatol, nootkatone, and valencene-11,12-epoxide accumulated preferably inside the fungal cells. Di- and poly-oxygenated products, such as nootkatone-11,12-epoxide, were found solely in the culture medium, indicating an active transport of these metabolites into the extracellular compartment during (+)-valencene detoxification. These metabolic properties may have contributed to the high tolerance of the fungus towards the exogenous hydrocarbon. PMID:15602686

  4. Comparative Analysis of Secretome Profiles of Manganese(II)-Oxidizing Ascomycete Fungi

    PubMed Central

    Zeiner, Carolyn A.; Purvine, Samuel O.; Zink, Erika M.; Paša-Tolić, Ljiljana; Chaput, Dominique L.; Haridas, Sajeet; Wu, Si; LaButti, Kurt; Grigoriev, Igor V.; Henrissat, Bernard; Santelli, Cara M.; Hansel, Colleen M.

    2016-01-01

    Fungal secretomes contain a wide range of hydrolytic and oxidative enzymes, including cellulases, hemicellulases, pectinases, and lignin-degrading accessory enzymes, that synergistically drive litter decomposition in the environment. While secretome studies of model organisms such as Phanerochaete chrysosporium and Aspergillus species have greatly expanded our knowledge of these enzymes, few have extended secretome characterization to environmental isolates or conducted side-by-side comparisons of diverse species. Thus, the mechanisms of carbon degradation by many ubiquitous soil fungi remain poorly understood. Here we use a combination of LC-MS/MS, genomic, and bioinformatic analyses to characterize and compare the protein composition of the secretomes of four recently isolated, cosmopolitan, Mn(II)-oxidizing Ascomycetes (Alternaria alternata SRC1lrK2f, Stagonospora sp. SRC1lsM3a, Pyrenochaeta sp. DS3sAY3a, and Paraconiothyrium sporulosum AP3s5-JAC2a). We demonstrate that the organisms produce a rich yet functionally similar suite of extracellular enzymes, with species-specific differences in secretome composition arising from unique amino acid sequences rather than overall protein function. Furthermore, we identify not only a wide range of carbohydrate-active enzymes that can directly oxidize recalcitrant carbon, but also an impressive suite of redox-active accessory enzymes that suggests a role for Fenton-based hydroxyl radical formation in indirect, non-specific lignocellulose attack. Our findings highlight the diverse oxidative capacity of these environmental isolates and enhance our understanding of the role of filamentous Ascomycetes in carbon turnover in the environment. PMID:27434633

  5. Comparative Analysis of Secretome Profiles of Manganese(II)-Oxidizing Ascomycete Fungi.

    PubMed

    Zeiner, Carolyn A; Purvine, Samuel O; Zink, Erika M; Paša-Tolić, Ljiljana; Chaput, Dominique L; Haridas, Sajeet; Wu, Si; LaButti, Kurt; Grigoriev, Igor V; Henrissat, Bernard; Santelli, Cara M; Hansel, Colleen M

    2016-01-01

    Fungal secretomes contain a wide range of hydrolytic and oxidative enzymes, including cellulases, hemicellulases, pectinases, and lignin-degrading accessory enzymes, that synergistically drive litter decomposition in the environment. While secretome studies of model organisms such as Phanerochaete chrysosporium and Aspergillus species have greatly expanded our knowledge of these enzymes, few have extended secretome characterization to environmental isolates or conducted side-by-side comparisons of diverse species. Thus, the mechanisms of carbon degradation by many ubiquitous soil fungi remain poorly understood. Here we use a combination of LC-MS/MS, genomic, and bioinformatic analyses to characterize and compare the protein composition of the secretomes of four recently isolated, cosmopolitan, Mn(II)-oxidizing Ascomycetes (Alternaria alternata SRC1lrK2f, Stagonospora sp. SRC1lsM3a, Pyrenochaeta sp. DS3sAY3a, and Paraconiothyrium sporulosum AP3s5-JAC2a). We demonstrate that the organisms produce a rich yet functionally similar suite of extracellular enzymes, with species-specific differences in secretome composition arising from unique amino acid sequences rather than overall protein function. Furthermore, we identify not only a wide range of carbohydrate-active enzymes that can directly oxidize recalcitrant carbon, but also an impressive suite of redox-active accessory enzymes that suggests a role for Fenton-based hydroxyl radical formation in indirect, non-specific lignocellulose attack. Our findings highlight the diverse oxidative capacity of these environmental isolates and enhance our understanding of the role of filamentous Ascomycetes in carbon turnover in the environment. PMID:27434633

  6. Analysis of Circadian Rhythms in the Basal Filamentous Ascomycete Pyronema confluens

    PubMed Central

    Traeger, Stefanie; Nowrousian, Minou

    2015-01-01

    Many organisms use circadian clocks to adapt to daily changes in the environment. Major insights into the molecular mechanisms of circadian oscillators have been gained through studies of the model organism Neurospora crassa; however, little is known about molecular components of circadian clocks in other fungi. An important part of the N. crassa circadian clock is the frequency (frq) gene, homologs of which can be found in Sordariomycetes, Dothideomycetes, and Leotiomycetes, but not Eurotiomycetes. Recently, we identified a frq homolog in Pyronema confluens, a member of the early-diverging Pezizomycete lineage of filamentous ascomycetes. The P. confluens FRQ shares many conserved domains with the N. crassa FRQ. However, there is no known morphological phenotype showing overt circadian rhythmicity in P. confluens. To investigate whether a molecular clock is present, we analyzed frq transcription in constant darkness, and found circadian oscillation of frq with a peak in the subjective morning. This rhythm was temperature compensated. To identify additional clock-controlled genes, we performed RNA sequencing of two time points (subjective morning and evening). Circadian expression of two morning-specific genes was verified by reverse transcription quantitative polymerase chain reaction (RT-qPCR) over a full time course, whereas expression of two putative morning-specific and five putative evening-specific genes could not be verified as circadian. frq expression was synchronized, but not entrained by light. In summary, we have found evidence for two of the three main properties of circadian rhythms (free-running rhythm, temperature compensation) in P. confluens, suggesting that a circadian clock with rhythmically expressed frq is present in this basal filamentous ascomycete. PMID:26254031

  7. Eisosome Organization in the Filamentous AscomyceteAspergillus nidulans▿†

    PubMed Central

    Vangelatos, Ioannis; Roumelioti, Katerina; Gournas, Christos; Suarez, Teresa; Scazzocchio, Claudio; Sophianopoulou, Vicky

    2010-01-01

    Eisosomes are subcortical organelles implicated in endocytosis and have hitherto been described only in Saccharomyces cerevisiae. They comprise two homologue proteins, Pil1 and Lsp1, which colocalize with the transmembrane protein Sur7. These proteins are universally conserved in the ascomycetes. We identify in Aspergillus nidulans (and in all members of the subphylum Pezizomycotina) two homologues of Pil1/Lsp1, PilA and PilB, originating from a duplication independent from that extant in the subphylum Saccharomycotina. In the aspergilli there are several Sur7-like proteins in each species, including one strict Sur7 orthologue (SurG in A. nidulans). In A. nidulans conidiospores, but not in hyphae, the three proteins colocalize at the cell cortex and form tightly packed punctate structures that appear different from the clearly distinct eisosome patches observed in S. cerevisiae. These structures are assembled late during the maturation of conidia. In mycelia, punctate structures are present, but they are composed only of PilA, while PilB is diffused in the cytoplasm and SurG is located in vacuoles and endosomes. Deletion of each of the genes does not lead to any obvious growth phenotype, except for moderate resistance to itraconazole. We could not find any obvious association between mycelial (PilA) eisosome-like structures and endocytosis. PilA and SurG are necessary for conidial eisosome organization in ways that differ from those for their S. cerevisiae homologues. These data illustrate that conservation of eisosomal proteins within the ascomycetes is accompanied by a striking functional divergence. PMID:20693301

  8. Calnexin induces expansion of antigen-specific CD4(+) T cells that confer immunity to fungal ascomycetes via conserved epitopes.

    PubMed

    Wüthrich, Marcel; Brandhorst, Tristan T; Sullivan, Thomas D; Filutowicz, Hanna; Sterkel, Alana; Stewart, Douglas; Li, Mengyi; Lerksuthirat, Tassanee; LeBert, Vanessa; Shen, Zu Ting; Ostroff, Gary; Deepe, George S; Hung, Chiung Yu; Cole, Garry; Walter, Jennifer A; Jenkins, Marc K; Klein, Bruce

    2015-04-01

    Fungal infections remain a threat due to the lack of broad-spectrum fungal vaccines and protective antigens. Recent studies showed that attenuated Blastomyces dermatitidis confers protection via T cell recognition of an unknown but conserved antigen. Using transgenic CD4(+) T cells recognizing this antigen, we identify an amino acid determinant within the chaperone calnexin that is conserved across diverse fungal ascomycetes. Calnexin, typically an ER protein, also localizes to the surface of yeast, hyphae, and spores. T cell epitope mapping unveiled a 13-residue sequence conserved across Ascomycota. Infection with divergent ascomycetes, including dimorphic fungi, opportunistic molds, and the agent causing white nose syndrome in bats, induces expansion of calnexin-specific CD4(+) T cells. Vaccine delivery of calnexin in glucan particles induces fungal antigen-specific CD4(+) T cell expansion and resistance to lethal challenge with multiple fungal pathogens. Thus, the immunogenicity and conservation of calnexin make this fungal protein a promising vaccine target. PMID:25800545

  9. Calnexin induces expansion of antigen-specific CD4+ T cells that confer immunity to fungal ascomycetes via conserved epitopes

    PubMed Central

    Wüthrich, Marcel; Brandhorst, Tristan T.; Sullivan, Thomas D.; Filutowicz, Hanna; Sterkel, Alana; Stewart, Douglas; Li, Mengyi; Lerksuthirat, Tassanee; LeBert, Vanessa; Shen, Zu Ting; Ostroff, Gary; Deepe, George S.; Hung, Chiung Yu; Cole, Garry; Walter, Jennifer A.; Jenkins, Marc K.; Klein, Bruce

    2015-01-01

    Fungal infections remain a threat due to the lack of broad spectrum fungal vaccines and protective antigens. Recent studies showed that attenuated Blastomyces dermatitidis confers protection via T cell recognition of an unknown, but conserved antigen. Using transgenic CD4+ T cells recognizing this antigen, we identify an amino acid determinant within the chaperone calnexin that is conserved across diverse fungal ascomycetes. Calnexin, typically an ER protein, also localizes to the surface of yeast, hyphae and spores. T cell epitope mapping unveiled a 13-residue sequence conserved across Ascomycota. Infection with divergent ascomycetes including dimorphic fungi, opportunistic molds, and the agent causing white nose syndrome in bats induces expansion of calnexin-specific CD4+ T cells. Vaccine delivery of calnexin in glucan particles induces fungal antigen-specific CD4+ T cell expansion and resistance to lethal challenge with multiple fungal pathogens. Thus, the immunogeneticity and conservation of calnexin make this fungal protein a promising vaccine target. PMID:25800545

  10. Long-term experimental warming alters community composition of ascomycetes in Alaskan moist and dry arctic tundra.

    PubMed

    Semenova, Tatiana A; Morgado, Luis N; Welker, Jeffrey M; Walker, Marilyn D; Smets, Erik; Geml, József

    2015-01-01

    Arctic tundra regions have been responding to global warming with visible changes in plant community composition, including expansion of shrubs and declines in lichens and bryophytes. Even though it is well known that the majority of arctic plants are associated with their symbiotic fungi, how fungal community composition will be different with climate warming remains largely unknown. In this study, we addressed the effects of long-term (18 years) experimental warming on the community composition and taxonomic richness of soil ascomycetes in dry and moist tundra types. Using deep Ion Torrent sequencing, we quantified how OTU assemblage and richness of different orders of Ascomycota changed in response to summer warming. Experimental warming significantly altered ascomycete communities with stronger responses observed in the moist tundra compared with dry tundra. The proportion of several lichenized and moss-associated fungi decreased with warming, while the proportion of several plant and insect pathogens and saprotrophic species was higher in the warming treatment. The observed alterations in both taxonomic and ecological groups of ascomycetes are discussed in relation to previously reported warming-induced shifts in arctic plant communities, including decline in lichens and bryophytes and increase in coverage and biomass of shrubs. PMID:25522194

  11. A putative mitochondrial fission gene from the ectomycorrhizal ascomycete Tuber borchii Vittad.: cloning, characterisation and phylogeny.

    PubMed

    Guidi, C; Zeppa, S; Barbieri, E; Zambonelli, A; Polidori, E; Potenza, L; Stocchi, V

    2003-11-01

    Mitochondrial binary division is a complex process occurring in multiple steps, mediated by several proteins. In Saccharomyces cerevisiae, a mitochondrial membrane protein, Fis1p, is required for the proper assembly of the mitochondrial division apparatus. In this study, we report the cloning, characterisation and phylogenetic analysis of Tbfis1, a gene from the ectomycorrhizal ascomycetous truffle Tuber borchii, encoding for an orthologue of S. cerevisiae Fis1p. The Tbfis1 coding region consists of a 468-nucleotide open reading frame interrupted by four introns, which encodes for a polypeptide of 155 amino acids, having a predicted transmembrane domain structure typical of the Fis1p Family. Southern blot analysis revealed that Tbfis1 is a single-copy gene in the T. borchii genome. Tbfis1 is highly expressed during the first stages of T. borchii fruit body ripening, while its expression decreases during T. borchii mycelium ageing. Also, Virtual Northern blot analysis revealed Tbfis1 expression in the symbiotic phase of the fungus life cycle. Phylogenetic analysis allowed the identification of Tbfis1 orthologues in filamentous fungi, yeasts, plants, worms, flies and mammals, indicating that the function of the protein coded by this gene has been conserved during evolution. PMID:12910371

  12. A high-affinity ammonium transporter from the mycorrhizal ascomycete Tuber borchii.

    PubMed

    Montanini, Barbara; Moretto, Nadia; Soragni, Elisabetta; Percudani, Riccardo; Ottonello, Simone

    2002-06-01

    An ammonium transporter cDNA, named TbAMT1, was isolated from the ectomycorrhizal ascomycetous truffle Tuber borchii. The polypeptide encoded by TbAMT1 (52 kDa) functionally complements ammonium uptake-defective yeast mutants and shares sequence similarity with previously characterized ammonium transporters from Saccharomyces (Mep) and Arabidopsis (AtAMT1). Structural characteristics common to the Mep/Amt family and peculiar features of the Tuber transporter have been evidenced by a detailed topological model of the TbAMT1 protein, which predicts 11 transmembrane helices with an N terminus(OUT)/C terminus(IN) orientation. As revealed by uptake/competition experiments conducted in yeast, TbAMT1 is a high-affinity transporter with an apparent K(m) for ammonium of 2 microM. The TbAMT1 mRNA was very slowly, yet specifically upregulated in nitrogen-deprived T. borchii mycelia. Instead, a much faster return to basal expression levels was observed upon resupplementation of either ammonium or nitrate, which thus appear to be utilized as equally effective nitrogen sources by Tuber mycelia. PMID:12051892

  13. "Hanseniaspora uvarum" the ultrastructural morphology of a rare ascomycete, isolated from oral thrush.

    PubMed

    Emmanouil-Nikoloussi, E; Kanellaki-Kyparissi, M; Papavassiliou, P; Koliakos, K; Dermentzopoulou, M; Foroglou, C

    1994-01-01

    Superficial fungal infections, including oral thrush, often affect aged full denture wearers and many individuals over 65 years old. The aim of this study was to examine the ultrastructural morphology of a very rare yeast, named Hanseniaspora uvarum/guillermondi, member of the Ascomycetes family, whose pathogenesis and behaviour is not widely known. The yeast was isolated from whitish lesions of the buccal mucosa of an 70 years old woman. The specimen was collected with a mouth swab and cultured in Sabourauds-Dextrose agar. The identification of the organism was performed on the Api 20C Aux system. The yeast colonies, after fixation in glutaraldehyde 3% for 1 hour were immersed in OsO4 1% solution for 1 hour and were "in tissue" stained with uranyl acetate. Ultrathin sections, were observed with TEM Jeol C x 100. Our ultrastructural observations showed that this yeast had a thick cell wall in which the outer surface appeared fuzzy. In some yeasts we observed multilayered intracytoplasmic membrane a figure which is not described as far as we know in any yeast. Many vacuoles were frequently observed in the cytoplasm and especially in the center of the oval shaped cells. Bilateral budding which form ascospores is identical for the morphology of this yeast. PMID:7994154

  14. The regulator of nitrate assimilation in ascomycetes is a dimer which binds a nonrepeated, asymmetrical sequence.

    PubMed

    Strauss, J; Muro-Pastor, M I; Scazzocchio, C

    1998-03-01

    The regulation of nitrate assimilation seems to follow the same pattern in all ascomycetes where this process has been studied. We show here by in vitro binding studies and a number of protection and interference techniques that the transcription factor mediating nitrate induction in Aspergillus nidulans, a protein containing a binuclear zinc cluster DNA binding domain, recognizes an asymmetrical sequence of the form CTCC GHGG. We further show that the protein binds to its consensus site as a dimer. We establish the role of the putative dimerization element by its ability to replace the analogous element of the cI protein of phage lambda. Mutagenesis of crucial leucines of the dimerization element affect both the binding ability of the dimer and the conformation of the resulting protein-DNA complex. This is the first case to be described where a dimer recognizes such an asymmetrical nonrepeated sequence, presumably by each monomeric subunit making different contacts with different DNA half-sites. PMID:9488449

  15. Bradymyces gen. nov. (Chaetothyriales, Trichomeriaceae), a new ascomycete genus accommodating poorly differentiated melanized fungi.

    PubMed

    Hubka, Vit; Réblová, Martina; Rehulka, Jiří; Selbmann, Laura; Isola, Daniela; de Hoog, Sybren G; Kolařík, Miroslav

    2014-11-01

    Three slow growing, melanized and morphologically poorly differentiated fungal strains were isolated from a hyperaemic focus near the enlarged spleen of a farmed rainbow trout (Oncorhynchus mykiss) and from a rock collected at 3,200 m a. s. l. (Alps, Italy). Two phylogenetic analyses of the combined nuc18S and nuc28S rDNA and ITS rDNA and β-tubulin sequences showed that these isolates belong to the Trichomeriaceae, a family of the ascomycete order Chaetothyriales containing black yeasts that cause infections in humans and animals. The strains form a well-supported monophyletic clade. The new genus Bradymyces, with two new species, Bradymyces oncorhynchi and Bradymyces alpinus, is proposed based on phylogenetic, ecophysiological and morphological data. It is characterized by the presence of moniliform hyphae, blastic proliferation, endoconidia, multicellular and muriform bodies, and bodies with dark fragmented incrustations on the surface. Bradymyces most closely resembles members of Knufia. The ex-type isolate of B. oncorhynchi CCF 4369(T) ( = CBS 133066(T) = CCFEE 6134(T)) represents the first case of a Trichomeriaceae member isolated from cold-blooded water vertebrates. B. alpinus [ex-type strain CCFEE 5493(T) ( = CBS 138368(T) = CCF 4803(T))] is represented by two isolates from a single locality in the Alps and in contrast to B. oncorhynchi shows overall slower growth parameters and does not grow at 25 °C. PMID:25164483

  16. Starmerella orientalis f.a., sp. nov., an ascomycetous yeast species isolated from flowers.

    PubMed

    Alimadadi, Nayyereh; Soudi, Mohammad Reza; Wang, Shi-An; Wang, Qi-Ming; Talebpour, Zahra; Bai, Feng-Yan

    2016-03-01

    Four strains of a novel ascomycetous yeast species were isolated from flowers in Iran and China. Phylogenetic analysis of the sequences of the ITS region (including 5.8S rRNA gene) and the LSU rRNA gene D1/D2 domains indicated that these strains belong to the Starmerella clade and show divergence from previously described species in this clade. Growth reactions on carbon and nitrogen sources were similar to those observed in related species of the Starmerella clade. Sexual reproduction was not observed after mating tests on different sporulation media. Based on physiological characteristics and phylogeny of rRNA gene sequences, the novel species is most closely related to Candida (iter. nom. Starmerella) powellii and Candida (iter. nom. Starmerella) floricola. It is therefore assigned to the genus Starmerella and described as Starmerella orientalis f.a., sp. nov. The type strain is SAM09T ( = IBRC-M 30204T = CBS 14142T). The MycoBank accession number is MB 814379. PMID:26780917

  17. Functional properties and differential mode of regulation of the nitrate transporter from a plant symbiotic ascomycete

    PubMed Central

    Montanini, Barbara; Viscomi, Arturo R.; Bolchi, Angelo; Martin, Yusé; Siverio, José M.; Balestrini, Raffaella; Bonfante, Paola; Ottonello, Simone

    2005-01-01

    Nitrogen assimilation by plant symbiotic fungi plays a central role in the mutualistic interaction established by these organisms, as well as in nitrogen flux in a variety of soils. In the present study, we report on the functional properties, structural organization and distinctive mode of regulation of TbNrt2 (Tuber borchii NRT2 family transporter), the nitrate transporter of the mycorrhizal ascomycete T. borchii. As revealed by experiments conducted in a nitrate-uptake-defective mutant of the yeast Hansenula polymorpha, TbNrt2 is a high-affinity transporter (Km=4.7 μM nitrate) that is bispecific for nitrate and nitrite. It is expressed in free-living mycelia and in mycorrhizae, where it preferentially accumulates in the plasma membrane of root-contacting hyphae. The TbNrt2 mRNA, which is transcribed from a single-copy gene clustered with the nitrate reductase gene in the T. borchii genome, was specifically up-regulated following transfer of mycelia to nitrate- (or nitrite)-containing medium. However, at variance with the strict nitrate-dependent induction commonly observed in other organisms, TbNrt2 was also up-regulated (at both the mRNA and the protein level) following transfer to a nitrogen-free medium. This unusual mode of regulation differs from that of the adjacent nitrate reductase gene, which was expressed at basal levels under nitrogen deprivation conditions and required nitrate for induction. The functional and expression properties, described in the present study, delineate TbNrt2 as a versatile transporter that may be especially suited to cope with the fluctuating (and often low) mineral nitrogen concentrations found in most natural, especially forest, soils. PMID:16201972

  18. Functional properties and differential mode of regulation of the nitrate transporter from a plant symbiotic ascomycete.

    PubMed

    Montanini, Barbara; Viscomi, Arturo R; Bolchi, Angelo; Martin, Yusé; Siverio, José M; Balestrini, Raffaella; Bonfante, Paola; Ottonello, Simone

    2006-02-15

    Nitrogen assimilation by plant symbiotic fungi plays a central role in the mutualistic interaction established by these organisms, as well as in nitrogen flux in a variety of soils. In the present study, we report on the functional properties, structural organization and distinctive mode of regulation of TbNrt2 (Tuber borchii NRT2 family transporter), the nitrate transporter of the mycorrhizal ascomycete T. borchii. As revealed by experiments conducted in a nitrate-uptake-defective mutant of the yeast Hansenula polymorpha, TbNrt2 is a high-affinity transporter (K(m)=4.7 microM nitrate) that is bispecific for nitrate and nitrite. It is expressed in free-living mycelia and in mycorrhizae, where it preferentially accumulates in the plasma membrane of root-contacting hyphae. The TbNrt2 mRNA, which is transcribed from a single-copy gene clustered with the nitrate reductase gene in the T. borchii genome, was specifically up-regulated following transfer of mycelia to nitrate- (or nitrite)-containing medium. However, at variance with the strict nitrate-dependent induction commonly observed in other organisms, TbNrt2 was also up-regulated (at both the mRNA and the protein level) following transfer to a nitrogen-free medium. This unusual mode of regulation differs from that of the adjacent nitrate reductase gene, which was expressed at basal levels under nitrogen deprivation conditions and required nitrate for induction. The functional and expression properties, described in the present study, delineate TbNrt2 as a versatile transporter that may be especially suited to cope with the fluctuating (and often low) mineral nitrogen concentrations found in most natural, especially forest, soils. PMID:16201972

  19. Repeat-Associated Fission Yeast-Like Regional Centromeres in the Ascomycetous Budding Yeast Candida tropicalis.

    PubMed

    Chatterjee, Gautam; Sankaranarayanan, Sundar Ram; Guin, Krishnendu; Thattikota, Yogitha; Padmanabhan, Sreedevi; Siddharthan, Rahul; Sanyal, Kaustuv

    2016-02-01

    The centromere, on which kinetochore proteins assemble, ensures precise chromosome segregation. Centromeres are largely specified by the histone H3 variant CENP-A (also known as Cse4 in yeasts). Structurally, centromere DNA sequences are highly diverse in nature. However, the evolutionary consequence of these structural diversities on de novo CENP-A chromatin formation remains elusive. Here, we report the identification of centromeres, as the binding sites of four evolutionarily conserved kinetochore proteins, in the human pathogenic budding yeast Candida tropicalis. Each of the seven centromeres comprises a 2 to 5 kb non-repetitive mid core flanked by 2 to 5 kb inverted repeats. The repeat-associated centromeres of C. tropicalis all share a high degree of sequence conservation with each other and are strikingly diverged from the unique and mostly non-repetitive centromeres of related Candida species--Candida albicans, Candida dubliniensis, and Candida lusitaniae. Using a plasmid-based assay, we further demonstrate that pericentric inverted repeats and the underlying DNA sequence provide a structural determinant in CENP-A recruitment in C. tropicalis, as opposed to epigenetically regulated CENP-A loading at centromeres in C. albicans. Thus, the centromere structure and its influence on de novo CENP-A recruitment has been significantly rewired in closely related Candida species. Strikingly, the centromere structural properties along with role of pericentric repeats in de novo CENP-A loading in C. tropicalis are more reminiscent to those of the distantly related fission yeast Schizosaccharomyces pombe. Taken together, we demonstrate, for the first time, fission yeast-like repeat-associated centromeres in an ascomycetous budding yeast. PMID:26845548

  20. Mn(II) oxidation by an ascomycete fungus is linked to superoxide production during asexual reproduction

    PubMed Central

    Hansel, Colleen M.; Zeiner, Carolyn A.; Santelli, Cara M.; Webb, Samuel M.

    2012-01-01

    Manganese (Mn) oxides are among the most reactive minerals within the environment, where they control the bioavailability of carbon, nutrients, and numerous metals. Although the ability of microorganisms to oxidize Mn(II) to Mn(III/IV) oxides is scattered throughout the bacterial and fungal domains of life, the mechanism and physiological basis for Mn(II) oxidation remains an enigma. Here, we use a combination of compound-specific chemical assays, microspectroscopy, and electron microscopy to show that a common Ascomycete filamentous fungus, Stilbella aciculosa, oxidizes Mn(II) to Mn oxides by producing extracellular superoxide during cell differentiation. The reactive Mn oxide phase birnessite and the reactive oxygen species superoxide and hydrogen peroxide are colocalized at the base of asexual reproductive structures. Mn oxide formation is not observed in the presence of superoxide scavengers (e.g., Cu) and inhibitors of NADPH oxidases (e.g., diphenylene iodonium chloride), enzymes responsible for superoxide production and cell differentiation in fungi. Considering the recent identification of Mn(II) oxidation by NADH oxidase-based superoxide production by a common marine bacterium (Roseobacter sp.), these results introduce a surprising homology between some prokaryotic and eukaryotic organisms in the mechanisms responsible for Mn(II) oxidation, where oxidation appears to be a side reaction of extracellular superoxide production. Given the versatility of superoxide as a redox reactant and the widespread ability of fungi to produce superoxide, this microbial extracellular superoxide production may play a central role in the cycling and bioavailability of metals (e.g., Hg, Fe, Mn) and carbon in natural systems. PMID:22802654

  1. Mn(II) oxidation by an ascomycete fungus is linked to superoxide production during asexual reproduction

    SciTech Connect

    Hansel, C. M.; Zeiner, C. A.; Santelli, C. M.; Webb, S. M.

    2012-07-16

    Manganese (Mn) oxides are among the most reactive minerals within the environment, where they control the bioavailability of carbon, nutrients, and numerous metals. Although the ability of microorganisms to oxidize Mn(II) to Mn(III/IV) oxides is scattered throughout the bacterial and fungal domains of life, the mechanism and physiological basis for Mn(II) oxidation remains an enigma. Here, we use a combination of compound-specific chemical assays, microspectroscopy, and electron microscopy to show that a common Ascomycete filamentous fungus, Stilbella aciculosa, oxidizes Mn(II) to Mn oxides by producing extracellular superoxide during cell differentiation. The reactive Mn oxide phase birnessite and the reactive oxygen species superoxide and hydrogen peroxide are colocalized at the base of asexual reproductive structures. Mn oxide formation is not observed in the presence of superoxide scavengers (e.g., Cu) and inhibitors of NADPH oxidases (e.g., diphenylene iodonium chloride), enzymes responsible for superoxide production and cell differentiation in fungi. Considering the recent identification of Mn(II) oxidation by NADH oxidase-based superoxide production by a common marine bacterium (Roseobacter sp.), these results introduce a surprising homology between some prokaryotic and eukaryotic organisms in the mechanisms responsible for Mn(II) oxidation, where oxidation appears to be a side reaction of extracellular superoxide production. Finally, given the versatility of superoxide as a redox reactant and the widespread ability of fungi to produce superoxide, this microbial extracellular superoxide production may play a central role in the cycling and bioavailability of metals (e.g., Hg, Fe, Mn) and carbon in natural systems.

  2. Repeat-Associated Fission Yeast-Like Regional Centromeres in the Ascomycetous Budding Yeast Candida tropicalis

    PubMed Central

    Chatterjee, Gautam; Sankaranarayanan, Sundar Ram; Guin, Krishnendu; Thattikota, Yogitha; Padmanabhan, Sreedevi; Siddharthan, Rahul; Sanyal, Kaustuv

    2016-01-01

    The centromere, on which kinetochore proteins assemble, ensures precise chromosome segregation. Centromeres are largely specified by the histone H3 variant CENP-A (also known as Cse4 in yeasts). Structurally, centromere DNA sequences are highly diverse in nature. However, the evolutionary consequence of these structural diversities on de novo CENP-A chromatin formation remains elusive. Here, we report the identification of centromeres, as the binding sites of four evolutionarily conserved kinetochore proteins, in the human pathogenic budding yeast Candida tropicalis. Each of the seven centromeres comprises a 2 to 5 kb non-repetitive mid core flanked by 2 to 5 kb inverted repeats. The repeat-associated centromeres of C. tropicalis all share a high degree of sequence conservation with each other and are strikingly diverged from the unique and mostly non-repetitive centromeres of related Candida species—Candida albicans, Candida dubliniensis, and Candida lusitaniae. Using a plasmid-based assay, we further demonstrate that pericentric inverted repeats and the underlying DNA sequence provide a structural determinant in CENP-A recruitment in C. tropicalis, as opposed to epigenetically regulated CENP-A loading at centromeres in C. albicans. Thus, the centromere structure and its influence on de novo CENP-A recruitment has been significantly rewired in closely related Candida species. Strikingly, the centromere structural properties along with role of pericentric repeats in de novo CENP-A loading in C. tropicalis are more reminiscent to those of the distantly related fission yeast Schizosaccharomyces pombe. Taken together, we demonstrate, for the first time, fission yeast-like repeat-associated centromeres in an ascomycetous budding yeast. PMID:26845548

  3. Simulated aerial sprays for field cage evaluation of Beauveria bassiana and Metarhizium brunneum (Ascomycetes: Hypocreales) against Anabrus simplex (Orthoptera: Tettigoniidae) in Montana

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Field efficacy of the entomopathogenic Ascomycete Beauveria bassiana strain GHA and Metarhizium brunneum strain F52 was evaluated against nymphs of the Mormon cricket, Anabrus simplex. Fungi were applied with a new apparatus that allows simulated aerial sprays to 0.1m2 areas in the field. The Mormon...

  4. A chloride tolerant laccase from the plant pathogen ascomycete Botrytis aclada expressed at high levels in Pichia pastoris.

    PubMed

    Kittl, Roman; Mueangtoom, Kitti; Gonaus, Christoph; Khazaneh, Shima Tahvilda; Sygmund, Christoph; Haltrich, Dietmar; Ludwig, Roland

    2012-01-20

    Fungal laccases from basidiomycetous fungi are thoroughly investigated in respect of catalytic mechanism and industrial applications, but the number of reported and well characterized ascomycetous laccases is much smaller although they exhibit interesting catalytic properties. We report on a highly chloride tolerant laccase produced by the plant pathogen ascomycete Botrytis aclada, which was recombinantly expressed in Pichia pastoris with an extremely high yield and purified to homogeneity. In a fed-batch fermentation, 495 mg L(-1) of laccase was measured in the medium, which is the highest concentration obtained for a laccase by a yeast expression system. The recombinant B. aclada laccase has a typical molecular mass of 61,565 Da for the amino acid chain. The pI is approximately 2.4, a very low value for a laccase. Glycosyl residues attached to the recombinant protein make up for approximately 27% of the total protein mass. B. aclada laccase exhibits very low K(M) values and high substrate turnover numbers for phenolic and non-phenolic substrates at acidic and near neutral pH. The enzyme's stability increases in the presence of chloride ions and, even more important, its substrate turnover is only weakly inhibited by chloride ions (I(50)=1.4M), which is in sharp contrast to most other described laccases. This high chloride tolerance is mandatory for some applications such as implantable biofuel cells and laccase catalyzed reactions, which suffer from the presence of chloride ions. The high expression yield permits fast and easy production for further basic and applied research. PMID:22178779

  5. Genes That Bias Mendelian Segregation

    PubMed Central

    Grognet, Pierre; Lalucque, Hervé; Malagnac, Fabienne; Silar, Philippe

    2014-01-01

    Mendel laws of inheritance can be cheated by Meiotic Drive Elements (MDs), complex nuclear genetic loci found in various eukaryotic genomes and distorting segregation in their favor. Here, we identify and characterize in the model fungus Podospora anserina Spok1 and Spok2, two MDs known as Spore Killers. We show that they are related genes with both spore-killing distorter and spore-protecting responder activities carried out by the same allele. These alleles act as autonomous elements, exert their effects independently of their location in the genome and can act as MDs in other fungi. Additionally, Spok1 acts as a resistance factor to Spok2 killing. Genetical data and cytological analysis of Spok1 and Spok2 localization during the killing process suggest a complex mode of action for Spok proteins. Spok1 and Spok2 belong to a multigene family prevalent in the genomes of many ascomycetes. As they have no obvious cellular role, Spok1 and Spok2 Spore Killer genes represent a novel kind of selfish genetic elements prevalent in fungal genome that proliferate through meiotic distortion. PMID:24830502

  6. Agrobacterium-mediated gene transfer and enhanced green fluorescent protein visualization in the mycorrhizal ascomycete Tuber borchii: a first step towards truffle genetics.

    PubMed

    Grimaldi, Benedetto; de Raaf, Michiel A; Filetici, Patrizia; Ottonello, Simone; Ballario, Paola

    2005-07-01

    Mycorrhizal ascomycetes are ecologically and commercially important fungi that have proved impervious to genetic transformation so far. We report here on the successful transient transformation of Tuber borchii, an ectomycorrhizal ascomycete that colonizes a variety of trees and produces highly prized hypogeous fruitbodies known as "truffles". A hypervirulent Agrobacterium tumefaciens strain bearing the binary plasmid pBGgHg was used for transformation. The genes for hygromycin resistance and the enhanced green fluorescent protein (EGFP), both under the control of vector-borne promoters, were employed as selection markers. Patches of dark and fluorescent hyphae were observed upon fluorescence microscopic examination of hygromycin-resistant mycelia. The presence of EGFP was confirmed by both confocal microscopy and PCR analysis. The lack in the transformed mycelia of the DNA coding for kanamicin resistance (a trait encoded by a vector-borne gene located outside of the T-DNA region) indicates that Agrobacterium-mediated gene transfer correctly occurred in T. borchii. PMID:15868150

  7. Effect of the L499M mutation of the ascomycetous Botrytis aclada laccase on redox potential and catalytic properties

    SciTech Connect

    Osipov, Evgeny; Kittl, Roman; Shleev, Sergey; Dorovatovsky, Pavel; Tikhonova, Tamara; Popov, Vladimir

    2014-11-01

    The structures of the ascomycetous B. aclada laccase and its L499M T1-site mutant have been solved at 1.7 Å resolution. The mutant enzyme shows a 140 mV lower redox potential of the type 1 copper and altered kinetic behaviour. The wild type and the mutant have very similar structures, which makes it possible to relate the changes in the redox potential to the L499M mutation Laccases are members of a large family of multicopper oxidases that catalyze the oxidation of a wide range of organic and inorganic substrates accompanied by the reduction of dioxygen to water. These enzymes contain four Cu atoms per molecule organized into three sites: T1, T2 and T3. In all laccases, the T1 copper ion is coordinated by two histidines and one cysteine in the equatorial plane and is covered by the side chains of hydrophobic residues in the axial positions. The redox potential of the T1 copper ion influences the enzymatic reaction and is determined by the nature of the axial ligands and the structure of the second coordination sphere. In this work, the laccase from the ascomycete Botrytis aclada was studied, which contains conserved Ile491 and nonconserved Leu499 residues in the axial positions. The three-dimensional structures of the wild-type enzyme and the L499M mutant were determined by X-ray crystallography at 1.7 Å resolution. Crystals suitable for X-ray analysis could only be grown after deglycosylation. Both structures did not contain the T2 copper ion. The catalytic properties of the enzyme were characterized and the redox potentials of both enzyme forms were determined: E{sub 0} = 720 and 580 mV for the wild-type enzyme and the mutant, respectively. Since the structures of the wild-type and mutant forms are very similar, the change in the redox potential can be related to the L499M mutation in the T1 site of the enzyme.

  8. Gene Overexpression and RNA Silencing Tools for the Genetic Manipulation of the S-(+)-Abscisic Acid Producing Ascomycete Botrytis cinerea

    PubMed Central

    Ding, Zhong-Tao; Zhang, Zhi; Luo, Di; Zhou, Jin-Yan; Zhong, Juan; Yang, Jie; Xiao, Liang; Shu, Dan; Tan, Hong

    2015-01-01

    The phytopathogenic ascomycete Botrytis cinerea produces several secondary metabolites that have biotechnical significance and has been particularly used for S-(+)-abscisic acid production at the industrial scale. To manipulate the expression levels of specific secondary metabolite biosynthetic genes of B. cinerea with Agrobacterium tumefaciens-mediated transformation system, two expression vectors (pCBh1 and pCBg1 with different selection markers) and one RNA silencing vector, pCBSilent1, were developed with the In-Fusion assembly method. Both expression vectors were highly effective in constitutively expressing eGFP, and pCBSilent1 effectively silenced the eGFP gene in B. cinerea. Bcaba4, a gene suggested to participate in ABA biosynthesis in B. cinerea, was then targeted for gene overexpression and RNA silencing with these reverse genetic tools. The overexpression of bcaba4 dramatically induced ABA formation in the B. cinerea wild type strain Bc-6, and the gene silencing of bcaba4 significantly reduced ABA-production in an ABA-producing B. cinerea strain. PMID:25955649

  9. Gene Overexpression and RNA Silencing Tools for the Genetic Manipulation of the S-(+)-Abscisic Acid Producing Ascomycete Botrytis cinerea.

    PubMed

    Ding, Zhong-Tao; Zhang, Zhi; Luo, Di; Zhou, Jin-Yan; Zhong, Juan; Yang, Jie; Xiao, Liang; Shu, Dan; Tan, Hong

    2015-01-01

    The phytopathogenic ascomycete Botrytis cinerea produces several secondary metabolites that have biotechnical significance and has been particularly used for S-(+)-abscisic acid production at the industrial scale. To manipulate the expression levels of specific secondary metabolite biosynthetic genes of B. cinerea with Agrobacterium tumefaciens-mediated transformation system, two expression vectors (pCBh1 and pCBg1 with different selection markers) and one RNA silencing vector, pCBSilent1, were developed with the In-Fusion assembly method. Both expression vectors were highly effective in constitutively expressing eGFP, and pCBSilent1 effectively silenced the eGFP gene in B. cinerea. Bcaba4, a gene suggested to participate in ABA biosynthesis in B. cinerea, was then targeted for gene overexpression and RNA silencing with these reverse genetic tools. The overexpression of bcaba4 dramatically induced ABA formation in the B. cinerea wild type strain Bc-6, and the gene silencing of bcaba4 significantly reduced ABA-production in an ABA-producing B. cinerea strain. PMID:25955649

  10. Selection of native isolates of Beauveria bassiana (Ascomycetes: Clavicipitaceae) for the microbial control of Rhipicephalus (Boophilus) microplus (Acari: Ixodidae).

    PubMed

    Posadas, Julieta B; Lecuona, Roberto E

    2009-03-01

    Previously undiscovered isolates of Beauveria bassiana (Balsamo) Vuillemin (Ascomycetes: Clavicipitaceae) able to control Rhipicephalus (Boophilus) microplus (Canestrini) (Acari: Ixodidae) were obtained for the first time in Argentina. The isolates were selected from three sources: 1) soil samples from the provinces of Corrientes, Formosa, and Chaco, where ticks are endemic; 2) dead female ticks; and 3) the fungal collection from the Entomopathogenic Fungi Laboratory of IMYZA-INTA Castelar. To select the isolates, population parameters were estimated, LC50 values of the most virulent isolates were calculated, and fungi-acaricides compatibility assays carried out. Isolates B. bassiana 259 and 98 were the most virulent and effective to reduce the number of eggs, the percentage of larval hatching, and parameters rm (natural intrinsic growth rate) and lambda (infinite growth rate) of Rh. (Bo.) microplus populations. The values of LC50 were 1 x 10(7) and 1.15 x 10(7), respectively, when applied to Rh. (Bo.) microplus eggs. In addition, they were compatible with acaricides. A novel methodology to evaluate the entomopathogenic activity of fungi on Rh. (Bo.) microplus ticks is introduced. PMID:19351079

  11. Comparison of pectin-degrading fungal communities in temperate forests using glycosyl hydrolase family 28 pectinase primers targeting Ascomycete fungi.

    PubMed

    Gacura, Matthew D; Sprockett, Daniel D; Heidenreich, Bess; Blackwood, Christopher B

    2016-04-01

    Fungi have developed a wide assortment of enzymes to break down pectin, a prevalent polymer in plant cell walls that is important in plant defense and structure. One enzyme family used to degrade pectin is the glycosyl hydrolase family 28 (GH28). In this study we developed primers for the amplification of GH28 coding genes from a database of 293 GH28 sequences from 40 fungal genomes. The primers were used to successfully amplify GH28 pectinases from all Ascomycota cultures tested, but only three out of seven Basidiomycota cultures. In addition, we further tested the primers in PCRs on metagenomic DNA extracted from senesced tree leaves from different forest ecosystems, followed by cloning and sequencing. Taxonomic specificity for Ascomycota GH28 genes was tested by comparing GH28 composition in leaves to internal transcribed spacer (ITS) amplicon composition using pyrosequencing. All sequences obtained from GH28 primers were classified as Ascomycota; in contrast, ITS sequences indicated that fungal communities were up to 39% Basidiomycetes. Analysis of leaf samples indicated that both forest stand and ecosystem type were important in structuring fungal communities. However, site played the prominent role in explaining GH28 composition, whereas ecosystem type was more important for ITS composition, indicating possible genetic drift between populations of fungi. Overall, these primers will have utility in understanding relationships between fungal community composition and ecosystem processes, as well as detection of potentially pathogenic Ascomycetes. PMID:26899925

  12. Genomic Analysis of an Ascomycete Fungus from the Rice Planthopper Reveals How It Adapts to an Endosymbiotic Lifestyle

    PubMed Central

    Fan, Hai-Wei; Noda, Hiroaki; Xie, Hong-Qing; Suetsugu, Yoshitaka; Zhu, Qian-Hua; Zhang, Chuan-Xi

    2015-01-01

    A number of sap-sucking insects harbor endosymbionts, which are thought to play an important role in the development of their hosts. One of the most important rice pests, the brown planthopper (BPH), Nilaparvata lugens (Stål), harbors an obligatory yeast-like symbiont (YLS) that cannot be cultured in vitro. Genomic information on this YLS would be useful to better understand its evolution. In this study, we performed genome sequencing of the YLS using both 454 and Illumina approaches, generating a draft genome that shows a slightly smaller genome size and relatively higher GC content than most ascomycete fungi. A phylogenomic analysis of the YLS supported its close relationship with insect pathogens. We analyzed YLS-specific genes and the categories of genes that are likely to have changed in the YLS during its evolution. The loss of mating type locus demonstrated in the YLS sheds light on the evolution of eukaryotic symbionts. This information about the YLS genome provides a helpful guide for further understanding endosymbiotic associations in hemiptera and the symbiotic replacement of ancient bacteria with a multifunctional YLS seems to have been a successful change. PMID:26338189

  13. Functional characterization of sucrose non-fermenting 1 protein kinase complex genes in the Ascomycete Fusarium graminearum.

    PubMed

    Yu, Jungheon; Son, Hokyoung; Park, Ae Ran; Lee, Seung-Ho; Choi, Gyung Ja; Kim, Jin-Cheol; Lee, Yin-Won

    2014-02-01

    Sucrose non-fermenting 1 (SNF1) protein kinase complex is a heterotrimer that functions in energy homeostasis in eukaryotes by regulating transcription of glucose-repressible genes. Our previous study revealed that SNF1 of the homothallic ascomycete fungus Fusarium graminearum plays important roles in vegetative growth, sexual development, and virulence. In this study, we further identified the components of the SNF1 complex in F. graminearum and characterized their functions. We found that the SNF1 complex in F. graminearum consists of one alpha subunit (FgSNF1), one beta subunit (FgGAL83), and one gamma subunit (FgSNF4). Deletion of Fggal83 and Fgsnf4 resulted in alleviated phenotype changes in vegetative growth and sexual development as compared to those of the Fgsnf1 deletion mutant. However, all of the single, double, and triple deletion mutants among Fgsnf1, Fggal83, and Fgsnf4 had similar levels of decreased virulence. In addition, there was no synergistic effect of the mutant (single, double, or triple deletions of SNF1 complex component genes) phenotypes except for sucrose utilization. In this study, we revealed that FgSNF1 is mainly required for SNF1 complex functions, and the other two SNF1 complex components have adjunctive roles with FgSNF1 in sexual development and vegetative growth but have a major role in virulence in F. graminearum. PMID:24057127

  14. Comparison of pectin-degrading fungal communities in temperate forests using glycosyl hydrolase family 28 pectinase primers targeting Ascomycete fungi

    DOE PAGESBeta

    Gacura, Matthew D.; Sprockett, Daniel D.; Heidenreich, Bess; Blackwood, Christopher B.

    2016-02-17

    Here, fungi have developed a wide assortment of enzymes to break down pectin, a prevalent polymer in plant cell walls that is important in plant defense and structure. One enzyme family used to degrade pectin is the glycosyl hydrolase family 28 (GH28). In this studywe developed primers for the amplification of GH28 coding genes from a database of 293 GH28 sequences from40 fungal genomes. The primerswere used to successfully amplify GH28 pectinases from all Ascomycota cultures tested, but only three out of seven Basidiomycota cultures. In addition, we further tested the primers in PCRs on metagenomic DNA extracted from senescedmore » tree leaves from different forest ecosystems, followed by cloning and sequencing. Taxonomic specificity for Ascomycota GH28 genes was tested by comparing GH28 composition in leaves to internal transcribed spacer (ITS) amplicon composition using pyrosequencing. All sequences obtained from GH28 primers were classified as Ascomycota; in contrast, ITS sequences indicated that fungal communitieswere up to 39% Basidiomycetes. Analysis of leaf samples indicated that both forest stand and ecosystemtype were important in structuring fungal communities. However, site played the prominent role in explaining GH28 composition, whereas ecosystem type was more important for ITS composition, indicating possible genetic drift between populations of fungi. Overall, these primers will have utility in understanding relationships between fungal community composition and ecosystem processes, as well as detection of potentially pathogenic Ascomycetes.« less

  15. Effect of the L499M mutation of the ascomycetous Botrytis aclada laccase on redox potential and catalytic properties.

    PubMed

    Osipov, Evgeny; Polyakov, Konstantin; Kittl, Roman; Shleev, Sergey; Dorovatovsky, Pavel; Tikhonova, Tamara; Hann, Stephan; Ludwig, Roland; Popov, Vladimir

    2014-11-01

    Laccases are members of a large family of multicopper oxidases that catalyze the oxidation of a wide range of organic and inorganic substrates accompanied by the reduction of dioxygen to water. These enzymes contain four Cu atoms per molecule organized into three sites: T1, T2 and T3. In all laccases, the T1 copper ion is coordinated by two histidines and one cysteine in the equatorial plane and is covered by the side chains of hydrophobic residues in the axial positions. The redox potential of the T1 copper ion influences the enzymatic reaction and is determined by the nature of the axial ligands and the structure of the second coordination sphere. In this work, the laccase from the ascomycete Botrytis aclada was studied, which contains conserved Ile491 and nonconserved Leu499 residues in the axial positions. The three-dimensional structures of the wild-type enzyme and the L499M mutant were determined by X-ray crystallography at 1.7 Å resolution. Crystals suitable for X-ray analysis could only be grown after deglycosylation. Both structures did not contain the T2 copper ion. The catalytic properties of the enzyme were characterized and the redox potentials of both enzyme forms were determined: E0 = 720 and 580 mV for the wild-type enzyme and the mutant, respectively. Since the structures of the wild-type and mutant forms are very similar, the change in the redox potential can be related to the L499M mutation in the T1 site of the enzyme. PMID:25372682

  16. Effect of the L499M mutation of the ascomycetous Botrytis aclada laccase on redox potential and catalytic properties

    PubMed Central

    Osipov, Evgeny; Polyakov, Konstantin; Kittl, Roman; Shleev, Sergey; Dorovatovsky, Pavel; Tikhonova, Tamara; Hann, Stephan; Ludwig, Roland; Popov, Vladimir

    2014-01-01

    Laccases are members of a large family of multicopper oxidases that catalyze the oxidation of a wide range of organic and inorganic substrates accompanied by the reduction of dioxygen to water. These enzymes contain four Cu atoms per molecule organized into three sites: T1, T2 and T3. In all laccases, the T1 copper ion is coordinated by two histidines and one cysteine in the equatorial plane and is covered by the side chains of hydrophobic residues in the axial positions. The redox potential of the T1 copper ion influences the enzymatic reaction and is determined by the nature of the axial ligands and the structure of the second coordination sphere. In this work, the laccase from the ascomycete Botrytis aclada was studied, which contains conserved Ile491 and nonconserved Leu499 residues in the axial positions. The three-dimensional structures of the wild-type enzyme and the L499M mutant were determined by X-ray crystallography at 1.7 Å resolution. Crystals suitable for X-ray analysis could only be grown after deglycosylation. Both structures did not contain the T2 copper ion. The catalytic properties of the enzyme were characterized and the redox potentials of both enzyme forms were determined: E 0 = 720 and 580 mV for the wild-type enzyme and the mutant, respectively. Since the structures of the wild-type and mutant forms are very similar, the change in the redox potential can be related to the L499M mutation in the T1 site of the enzyme. PMID:25372682

  17. Contrasting Diversity and Host Association of Ectomycorrhizal Basidiomycetes versus Root-Associated Ascomycetes in a Dipterocarp Rainforest

    PubMed Central

    Sato, Hirotoshi; Tanabe, Akifumi S.; Toju, Hirokazu

    2015-01-01

    Root-associated fungi, including ectomycorrhizal and root-endophytic fungi, are among the most diverse and important belowground plant symbionts in dipterocarp rainforests. Our study aimed to reveal the biodiversity, host association, and community structure of ectomycorrhizal Basidiomycota and root-associated Ascomycota (including root-endophytic Ascomycota) in a lowland dipterocarp rainforest in Southeast Asia. The host plant chloroplast ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit (rbcL) region and fungal internal transcribed spacer 2 (ITS2) region were sequenced using tag-encoded, massively parallel 454 pyrosequencing to identify host plant and root-associated fungal taxa in root samples. In total, 1245 ascomycetous and 127 putative ectomycorrhizal basidiomycetous taxa were detected from 442 root samples. The putative ectomycorrhizal Basidiomycota were likely to be associated with closely related dipterocarp taxa to greater or lesser extents, whereas host association patterns of the root-associated Ascomycota were much less distinct. The community structure of the putative ectomycorrhizal Basidiomycota was possibly more influenced by host genetic distances than was that of the root-associated Ascomycota. This study also indicated that in dipterocarp rainforests, root-associated Ascomycota were characterized by high biodiversity and indistinct host association patterns, whereas ectomycorrhizal Basidiomycota showed less biodiversity and a strong host phylogenetic preference for dipterocarp trees. Our findings lead to the working hypothesis that root-associated Ascomycota, which might be mainly represented by root-endophytic fungi, have biodiversity hotspots in the tropics, whereas biodiversity of ectomycorrhizal Basidiomycota increases with host genetic diversity. PMID:25884708

  18. The mating-type chromosome in the filamentous ascomycete Neurospora tetrasperma represents a model for early evolution of sex chromosomes.

    PubMed

    Menkis, Audrius; Jacobson, David J; Gustafsson, Tim; Johannesson, Hanna

    2008-03-01

    We combined gene divergence data, classical genetics, and phylogenetics to study the evolution of the mating-type chromosome in the filamentous ascomycete Neurospora tetrasperma. In this species, a large non-recombining region of the mating-type chromosome is associated with a unique fungal life cycle where self-fertility is enforced by maintenance of a constant state of heterokaryosis. Sequence divergence between alleles of 35 genes from the two single mating-type component strains (i.e. the homokaryotic mat A or mat a-strains), derived from one N. tetrasperma heterokaryon (mat A+mat a), was analyzed. By this approach we were able to identify the boundaries and size of the non-recombining region, and reveal insight into the history of recombination cessation. The non-recombining region covers almost 7 Mbp, over 75% of the chromosome, and we hypothesize that the evolution of the mating-type chromosome in this lineage involved two successive events. The first event was contemporaneous with the split of N. tetrasperma from a common ancestor with its outcrossing relative N. crassa and suppressed recombination over at least 6.6 Mbp, and the second was confined to a smaller region in which recombination ceased more recently. In spite of the early origin of the first "evolutionary stratum", genealogies of five genes from strains belonging to an additional N. tetrasperma lineage indicate independent initiations of suppressed recombination in different phylogenetic lineages. This study highlights the shared features between the sex chromosomes found in the animal and plant kingdoms and the fungal mating-type chromosome, despite fungi having no separate sexes. As is often found in sex chromosomes of plants and animals, recombination suppression of the mating-type chromosome of N. tetrasperma involved more than one evolutionary event, covers the majority of the mating-type chromosome and is flanked by distal regions with obligate crossovers. PMID:18369449

  19. Contrasting diversity and host association of ectomycorrhizal basidiomycetes versus root-associated ascomycetes in a dipterocarp rainforest.

    PubMed

    Sato, Hirotoshi; Tanabe, Akifumi S; Toju, Hirokazu

    2015-01-01

    Root-associated fungi, including ectomycorrhizal and root-endophytic fungi, are among the most diverse and important belowground plant symbionts in dipterocarp rainforests. Our study aimed to reveal the biodiversity, host association, and community structure of ectomycorrhizal Basidiomycota and root-associated Ascomycota (including root-endophytic Ascomycota) in a lowland dipterocarp rainforest in Southeast Asia. The host plant chloroplast ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit (rbcL) region and fungal internal transcribed spacer 2 (ITS2) region were sequenced using tag-encoded, massively parallel 454 pyrosequencing to identify host plant and root-associated fungal taxa in root samples. In total, 1245 ascomycetous and 127 putative ectomycorrhizal basidiomycetous taxa were detected from 442 root samples. The putative ectomycorrhizal Basidiomycota were likely to be associated with closely related dipterocarp taxa to greater or lesser extents, whereas host association patterns of the root-associated Ascomycota were much less distinct. The community structure of the putative ectomycorrhizal Basidiomycota was possibly more influenced by host genetic distances than was that of the root-associated Ascomycota. This study also indicated that in dipterocarp rainforests, root-associated Ascomycota were characterized by high biodiversity and indistinct host association patterns, whereas ectomycorrhizal Basidiomycota showed less biodiversity and a strong host phylogenetic preference for dipterocarp trees. Our findings lead to the working hypothesis that root-associated Ascomycota, which might be mainly represented by root-endophytic fungi, have biodiversity hotspots in the tropics, whereas biodiversity of ectomycorrhizal Basidiomycota increases with host genetic diversity. PMID:25884708

  20. Development of a Conditional Gene Expression System Using a Zearalenone-Inducible Promoter for the Ascomycete Fungus Gibberella zeae▿

    PubMed Central

    Lee, Jungkwan; Son, Hokyoung; Lee, Seunghoon; Park, Ae Ran; Lee, Yin-Won

    2010-01-01

    The ascomycete fungus Gibberella zeae is an important plant pathogen that causes fusarium head blight on small grains. Molecular studies of this fungus have been performed extensively to uncover the biological mechanisms related to pathogenicity, toxin production, and sexual reproduction. Molecular methods, such as targeted gene deletion, gene overexpression, and gene fusion to green fluorescent protein (GFP), are relatively easy to perform with this fungus; however, conditional expression systems have not been developed. The purpose of this study was to identify a promoter that could be induced by zearalenone (ZEA) for the development of a conditional expression system in G. zeae. Through microarray analysis, we isolated one zearalenone response gene (ZEAR) whose expression was increased more than 50 times after ZEA treatment. Northern blot analysis showed that the ZEAR transcript dramatically increased after 1 h of ZEA treatment. To determine the utility of the ZEAR promoter, called Pzear, in a conditional expression system, we transformed a Pzear::GFP fusion construct into G. zeae. Our data showed a ZEA concentration-dependent increase in GFP expression. We also replaced the promoter of G. zeae metE (GzmetE), an essential gene for methionine biosynthesis, with the Pzear promoter. The growth of the Pzear-GzmetE mutant on minimal medium was dependent on the ZEA concentration supplemented in the medium and showed that GzMetE expression was induced by ZEA. This study is the first report of an inducible promoter in G. zeae. Our system will be useful for the characterization of essential gene functions in this fungus through differential and ZEA-dependent gene expression. In addition, the Pzear promoter may be applicable as a biosensor for the detection of ZEA contamination in agricultural products. PMID:20348311

  1. DNA barcoding and isolation of vertically transmitted ascomycetes in sorghum from Burkina Faso: Epicoccum sorghinum is dominant in seedlings and appears as a common root pathogen.

    PubMed

    Stokholm, Michaela S; Wulff, Ednar G; Zida, Elisabeth P; Thio, Ibié G; Néya, James B; Soalla, Romain W; Głazowska, Sylwia E; Andresen, Marianne; Topbjerg, Henrik B; Boelt, Birte; Lund, Ole S

    2016-10-01

    Molecular identification of fungal taxa commonly transmitted through seeds of sorghum in Western Africa is lacking. In the present study, farm-saved seeds, collected from four villages in Northern Burkina Faso, were surface sterilized and the distribution of fungal DNA in seeds and seven-day-old seedlings was analyzed by 18S ribosomal DNA (rDNA) amplicon sequencing. More than 99% of the fungal rDNA was found to originate from ascomycetes. The distribution of ascomycetes at species level was subsequently analyzed by barcoding of ITS2 rDNA. Eighteen Operational Taxonomic Units (OTUs) were identified from seedlings, compared to 29 OTUs from seeds. The top-eight most abundant ascomycete OTUs from seedlings were annotated as: Epicoccum sorghinum, Fusarium thapsinum, four different Curvularia spp., Exserohilum rostratum and Alternaria longissima. These OTUs were also present in amplicons from seed samples collected in Central Burkina Faso confirming a common occurrence. E. sorghinum was highly predominant in seedlings both measured by DNA analysis and by isolation. The dominance of E. sorghinum was particularly strong in roots from poorly growing seedlings. Pathogenicity of E. sorghinum isolates was compared to F. thapsinum by inoculation to seeds in vitro. Both fungal species caused significant inhibition of seedling growth (P<0.001) and Koch's postulates were fulfilled. Extensive, dark necrosis in roots was a typical symptom of E. sorghinum, whereas wilting of leaves was caused primarily by F. thapsinum. This study provides the first molecular approach to characterize the seedling mycoflora of sorghum in Western Africa and suggests E. sorghinum as a common root pathogen. PMID:27524652

  2. Purifying Selection and Birth-and-Death Evolution in the Class II Hydrophobin Gene Families of the Ascomycete Trichoderma/Hypocrea

    SciTech Connect

    kubicek, Christian P.; Baker, Scott E.; Gamauf, Christian; Kenerley, Chuck; Druzhinina, Irina S.

    2008-01-10

    Hydrophobins are proteins containing eight conserved cysteine residues that occur uniquely in mycelial fungi, where their main function is to confer hydrophobicity to fungal surfaces in contact with air and during attachment of hyphae to hydrophobic surfaces of hosts, symbiotic partners or of themselves resulting in morphogenetic signals. Based on their hydropathy patterns and their solubility characteristics, they are classified in class I and class II hydrophobins, the latter being found only in ascomycetes. Here we have investigated the mechanisms driving the evolution of the class II hydrophobins in nine species of the mycoparasitic ascomycetous genus Trichoderma/Hypocrea, using three fully sequenced genomes (H. jecorina=T. reesei, H. atroviridis=T. atroviride; H. virens=T. virens) and a total of 14.000 ESTs of six others (T. asperellum, H. lixii=T. harzianum, T. aggressivum var. europeae, T. longibrachiatum, T. cf. viride). The former three contained six, ten and nine members, which is the highest number found in any other ascomycete so far. They all showed the conserved four beta-strands/one helix structure, which is stabilized by four disulfide bonds. In addition, a small number of these HFBs contained an extended N-terminus rich in either praline and aspartate, or glycine-asparagine. Phylogenetic analysis reveals a mosaic of terminal clades contain duplicated genes and shows only three reasonably supported clades. Calculation of the ratio of differences in synonymous vs. non-synonymous nucleotide substitutions provides evidence for strong purifying selection (KS/Ka >> 1). A genome database search for class II HFBs from other ascomycetes retrieved a much smaller number of hydrophobins (2-4) from each species, and most of them were from Pyrenomycetes. A combined phylogeny of these sequences with those of Trichoderma showed that the Trichoderma HFBs mostly formed their own clades, whereas those of other pyrenomycetes occured in shared clades. Our study shows

  3. Antifungal mechanisms of a plant defensin MtDef4 are not conserved between the ascomycete fungi Neurospora crassa and Fusarium graminearum.

    PubMed

    El-Mounadi, Kaoutar; Islam, Kazi T; Hernández-Ortiz, Patricia; Read, Nick D; Shah, Dilip M

    2016-05-01

    Defensins play an important role in plant defense against fungal pathogens. The plant defensin, MtDef4, inhibits growth of the ascomycete fungi, Neurospora crassa and Fusarium graminearum, at micromolar concentrations. We have reported that MtDef4 is transported into the cytoplasm of these fungi and exerts its antifungal activity on intracellular targets. Here, we have investigated whether the antifungal mechanisms of MtDef4 are conserved in these fungi. We show that N. crassa and F. graminearum respond differently to MtDef4 challenge. Membrane permeabilization is required for the antifungal activity of MtDef4 against F. graminearum but not against N. crassa. We find that MtDef4 is targeted to different subcellular compartments in each fungus. Internalization of MtDef4 in N. crassa is energy-dependent and involves endocytosis. By contrast, MtDef4 appears to translocate into F. graminearum autonomously using a partially energy-dependent pathway. MtDef4 has been shown to bind to the phospholipid phosphatidic acid (PA). We provide evidence that the plasma membrane localized phospholipase D, involved in the biosynthesis of PA, is needed for entry of this defensin in N. crassa, but not in F. graminearum. To our knowledge, this is the first example of a defensin which inhibits the growth of two ascomycete fungi via different mechanisms. PMID:26801962

  4. A Fox2-dependent fatty acid ß-oxidation pathway coexists both in peroxisomes and mitochondria of the ascomycete yeast Candida lusitaniae.

    PubMed

    Gabriel, Frédéric; Accoceberry, Isabelle; Bessoule, Jean-Jacques; Salin, Bénédicte; Lucas-Guérin, Marine; Manon, Stephen; Dementhon, Karine; Noël, Thierry

    2014-01-01

    It is generally admitted that the ascomycete yeasts of the subphylum Saccharomycotina possess a single fatty acid ß-oxidation pathway located exclusively in peroxisomes, and that they lost mitochondrial ß-oxidation early during evolution. In this work, we showed that mutants of the opportunistic pathogenic yeast Candida lusitaniae which lack the multifunctional enzyme Fox2p, a key enzyme of the ß-oxidation pathway, were still able to grow on fatty acids as the sole carbon source, suggesting that C. lusitaniae harbored an alternative pathway for fatty acid catabolism. By assaying 14Cα-palmitoyl-CoA consumption, we demonstrated that fatty acid catabolism takes place in both peroxisomal and mitochondrial subcellular fractions. We then observed that a fox2Δ null mutant was unable to catabolize fatty acids in the mitochondrial fraction, thus indicating that the mitochondrial pathway was Fox2p-dependent. This finding was confirmed by the immunodetection of Fox2p in protein extracts obtained from purified peroxisomal and mitochondrial fractions. Finally, immunoelectron microscopy provided evidence that Fox2p was localized in both peroxisomes and mitochondria. This work constitutes the first demonstration of the existence of a Fox2p-dependent mitochondrial β-oxidation pathway in an ascomycetous yeast, C. lusitaniae. It also points to the existence of an alternative fatty acid catabolism pathway, probably located in peroxisomes, and functioning in a Fox2p-independent manner. PMID:25486052

  5. Phylogenetic analysis of β-xylanase SRXL1 of Sporisorium reilianum and its relationship with families (GH10 and GH11) of Ascomycetes and Basidiomycetes

    PubMed Central

    Álvarez-Cervantes, Jorge; Díaz-Godínez, Gerardo; Mercado-Flores, Yuridia; Gupta, Vijai Kumar; Anducho-Reyes, Miguel Angel

    2016-01-01

    In this paper, the amino acid sequence of the β-xylanase SRXL1 of Sporisorium reilianum, which is a pathogenic fungus of maize was used as a model protein to find its phylogenetic relationship with other xylanases of Ascomycetes and Basidiomycetes and the information obtained allowed to establish a hypothesis of monophyly and of biological role. 84 amino acid sequences of β-xylanase obtained from the GenBank database was used. Groupings analysis of higher-level in the Pfam database allowed to determine that the proteins under study were classified into the GH10 and GH11 families, based on the regions of highly conserved amino acids, 233–318 and 180–193 respectively, where glutamate residues are responsible for the catalysis. PMID:27040368

  6. First Structural Insights into α-l-Arabinofuranosidases from the Two GH62 Glycoside Hydrolase Subfamilies*

    PubMed Central

    Siguier, Béatrice; Haon, Mireille; Nahoum, Virginie; Marcellin, Marlène; Burlet-Schiltz, Odile; Coutinho, Pedro M.; Henrissat, Bernard; Mourey, Lionel; O'Donohue, Michael J.; Berrin, Jean-Guy; Tranier, Samuel; Dumon, Claire

    2014-01-01

    α-l-Arabinofuranosidases are glycoside hydrolases that specifically hydrolyze non-reducing residues from arabinose-containing polysaccharides. In the case of arabinoxylans, which are the main components of hemicellulose, they are part of microbial xylanolytic systems and are necessary for complete breakdown of arabinoxylans. Glycoside hydrolase family 62 (GH62) is currently a small family of α-l-arabinofuranosidases that contains only bacterial and fungal members. Little is known about the GH62 mechanism of action, because only a few members have been biochemically characterized and no three-dimensional structure is available. Here, we present the first crystal structures of two fungal GH62 α-l-arabinofuranosidases from the basidiomycete Ustilago maydis (UmAbf62A) and ascomycete Podospora anserina (PaAbf62A). Both enzymes are able to efficiently remove the α-l-arabinosyl substituents from arabinoxylan. The overall three-dimensional structure of UmAbf62A and PaAbf62A reveals a five-bladed β-propeller fold that confirms their predicted classification into clan GH-F together with GH43 α-l-arabinofuranosidases. Crystallographic structures of the complexes with arabinose and cellotriose reveal the important role of subsites +1 and +2 for sugar binding. Intriguingly, we observed that PaAbf62A was inhibited by cello-oligosaccharides and displayed binding affinity to cellulose although no activity was observed on a range of cellulosic substrates. Bioinformatic analyses showed that UmAbf62A and PaAbf62A belong to two distinct subfamilies within the GH62 family. The results presented here provide a framework to better investigate the structure-function relationships within the GH62 family. PMID:24394409

  7. Metabolites from nematophagous fungi and nematicidal natural products from fungi as an alternative for biological control. Part I: metabolites from nematophagous ascomycetes.

    PubMed

    Degenkolb, Thomas; Vilcinskas, Andreas

    2016-05-01

    Plant-parasitic nematodes are estimated to cause global annual losses of more than US$ 100 billion. The number of registered nematicides has declined substantially over the last 25 years due to concerns about their non-specific mechanisms of action and hence their potential toxicity and likelihood to cause environmental damage. Environmentally beneficial and inexpensive alternatives to chemicals, which do not affect vertebrates, crops, and other non-target organisms, are therefore urgently required. Nematophagous fungi are natural antagonists of nematode parasites, and these offer an ecophysiological source of novel biocontrol strategies. In this first section of a two-part review article, we discuss 83 nematicidal and non-nematicidal primary and secondary metabolites found in nematophagous ascomycetes. Some of these substances exhibit nematicidal activities, namely oligosporon, 4',5'-dihydrooligosporon, talathermophilins A and B, phomalactone, aurovertins D and F, paeciloxazine, a pyridine carboxylic acid derivative, and leucinostatins. Blumenol A acts as a nematode attractant. Other substances, such as arthrosporols and paganins, play a decisive role in the life cycle of the producers, regulating the formation of reproductive or trapping organs. We conclude by considering the potential applications of these beneficial organisms in plant protection strategies. PMID:26715220

  8. NPS6, Encoding a Nonribosomal Peptide Synthetase Involved in Siderophore-Mediated Iron Metabolism, Is a Conserved Virulence Determinant of Plant Pathogenic Ascomycetes[W

    PubMed Central

    Oide, Shinichi; Moeder, Wolfgang; Krasnoff, Stuart; Gibson, Donna; Haas, Hubertus; Yoshioka, Keiko; Turgeon, B. Gillian

    2006-01-01

    NPS6, encoding a nonribosomal peptide synthetase, is a virulence determinant in the maize (Zea mays) pathogen Cochliobolus heterostrophus and is involved in tolerance to H2O2. Deletion of NPS6 orthologs in the rice (Oryza sativa) pathogen, Cochliobolus miyabeanus, the wheat (Triticum aestivum) pathogen, Fusarium graminearum, and the Arabidopsis thaliana pathogen, Alternaria brassicicola, resulted in reduced virulence and hypersensitivity to H2O2. Introduction of the NPS6 ortholog from the saprobe Neurospora crassa to the Δnps6 strain of C. heterostrophus restored wild-type virulence to maize and tolerance to H2O2, demonstrating functional conservation in filamentous ascomycete phytopathogens and saprobes. Increased sensitivity to iron depletion was identified as a conserved phenotype of Δnps6 strains. Exogenous application of iron enhanced the virulence of Δnps6 strains of C. heterostrophus, C. miyabeanus, F. graminearum, and A. brassicicola to each host. NPS6 is responsible for the biosynthesis of extracellular siderophores by C. heterostrophus, F. graminearum, and A. brassicicola. Application of the extracellular siderophore of A. brassicicola restored wild-type virulence of the ΔAbnps6 strain to Arabidopsis. It is proposed that the role of extracellular siderophores in fungal virulence to plants is to supply an essential nutrient, iron, to their producers in planta and not to act as phytotoxins, depriving their hosts of iron. PMID:17056706

  9. Autophagy-Associated Protein SmATG12 Is Required for Fruiting-Body Formation in the Filamentous Ascomycete Sordaria macrospora.

    PubMed

    Werner, Antonia; Herzog, Britta; Frey, Stefan; Pöggeler, Stefanie

    2016-01-01

    In filamentous fungi, autophagy functions as a catabolic mechanism to overcome starvation and to control diverse developmental processes under normal nutritional conditions. Autophagy involves the formation of double-membrane vesicles, termed autophagosomes that engulf cellular components and bring about their degradation via fusion with vacuoles. Two ubiquitin-like (UBL) conjugation systems are essential for the expansion of the autophagosomal membrane: the UBL protein ATG8 is conjugated to the lipid phosphatidylethanolamine and the UBL protein ATG12 is coupled to ATG5. We recently showed that in the homothallic ascomycete Sordaria macrospora autophagy-related genes encoding components of the conjugation systems are required for fruiting-body development and/or are essential for viability. In the present work, we cloned and characterized the S. macrospora (Sm)atg12 gene. Two-hybrid analysis revealed that SmATG12 can interact with SmATG7 and SmATG3. To examine its role in S. macrospora, we replaced the open reading frame of Smatg12 with a hygromycin resistance cassette and generated a homokaryotic ΔSmatg12 knockout strain, which displayed slower vegetative growth under nutrient starvation conditions and was unable to form fruiting bodies. In the hyphae of S. macrospora EGFP-labeled SmATG12 was detected in the cytoplasm and as punctate structures presumed to be phagophores or phagophore assembly sites. Delivery of EGFP-labelled SmATG8 to the vacuole was entirely dependent on SmATG12. PMID:27309377

  10. Autophagy-Associated Protein SmATG12 Is Required for Fruiting-Body Formation in the Filamentous Ascomycete Sordaria macrospora

    PubMed Central

    Werner, Antonia; Herzog, Britta; Frey, Stefan; Pöggeler, Stefanie

    2016-01-01

    In filamentous fungi, autophagy functions as a catabolic mechanism to overcome starvation and to control diverse developmental processes under normal nutritional conditions. Autophagy involves the formation of double-membrane vesicles, termed autophagosomes that engulf cellular components and bring about their degradation via fusion with vacuoles. Two ubiquitin-like (UBL) conjugation systems are essential for the expansion of the autophagosomal membrane: the UBL protein ATG8 is conjugated to the lipid phosphatidylethanolamine and the UBL protein ATG12 is coupled to ATG5. We recently showed that in the homothallic ascomycete Sordaria macrospora autophagy-related genes encoding components of the conjugation systems are required for fruiting-body development and/or are essential for viability. In the present work, we cloned and characterized the S. macrospora (Sm)atg12 gene. Two-hybrid analysis revealed that SmATG12 can interact with SmATG7 and SmATG3. To examine its role in S. macrospora, we replaced the open reading frame of Smatg12 with a hygromycin resistance cassette and generated a homokaryotic ΔSmatg12 knockout strain, which displayed slower vegetative growth under nutrient starvation conditions and was unable to form fruiting bodies. In the hyphae of S. macrospora EGFP-labeled SmATG12 was detected in the cytoplasm and as punctate structures presumed to be phagophores or phagophore assembly sites. Delivery of EGFP-labelled SmATG8 to the vacuole was entirely dependent on SmATG12. PMID:27309377

  11. Biochemical and physicochemical processes contributing to the removal of endocrine-disrupting chemicals and pharmaceuticals by the aquatic ascomycete Phoma sp. UHH 5-1-03.

    PubMed

    Hofmann, Ulrike; Schlosser, Dietmar

    2016-03-01

    The environmentally widespread micropollutants bisphenol A (BPA), carbamazepine (CBZ), 17α-ethinylestradiol (EE2), diclofenac (DF), sulfamethoxazole (SMX), technical nonylphenol (t-NP) and triclosan (TCS) were used to assess the potential of the laccase-producing freshwater ascomycete Phoma sp. strain UHH 5-1-03 for micropollutant removal and to provide quantitative insights into the mechanisms involved. Biotransformation rates observed with whole fungal cells followed the rank order EE2 ≫ BPA > TCS > t-NP > DF > SMX > CBZ. Biosorption onto fungal mycelia was prominent for BPA, EE2, TCS and t-NP and insignificant for CBZ, DF and SMX. Enzymatic removal rates investigated with cell-free, laccase-containing culture supernatants of Phoma sp. followed the rank order EE2 > BPA > DF > t-NP > TCS and were insignificant for SMX and CBZ. Mass spectrometry-assisted investigations addressing metabolite formation from unlabelled and (13)C6-labelled DF and SMX yielded DF metabolites indicating hydroxylation, cyclisation and decarboxylation reactions, as well as oxidative coupling typical for laccase reactions. For SMX, several products characterised by lower molecular masses than the parent compound were found, and indications for deamination and formamide formation were obtained. Summarising, the obtained results suggest that the extracellular laccase of Phoma sp. largely contributes to fungal biotransformation of EE2, BPA, DF, TCS and t-NP, together with cell-associated enzymes such as, e.g. cytochrome P450 monooxygenases suggested by the appearance of hydroxylated metabolites from DF. Laccase does not seem to play any role in the metabolisation of SMX and CBZ, where yet to be identified cell-associated enzymes have to be considered instead. PMID:26536880

  12. Comparison and cross-species expression of the acetyl-CoA synthetase genes of the Ascomycete fungi, Aspergillus nidulans and Neurospora crassa.

    PubMed

    Connerton, I F; Fincham, J R; Sandeman, R A; Hynes, M J

    1990-03-01

    The genes encoding the acetate-inducible enzyme acetyl-coenzyme A synthetase from Neurospora crassa and Aspergillus nidulans (acu-5 and facA, respectively) have been cloned and their sequences compared. The predicted amino acid sequence of the Aspergillus enzyme has 670 amino acid residues and that of the Neurospora enzyme either 626 or 606 residues, depending upon which of the two possible initiation codons is used. The amino acid sequences following the second alternative AUG show 86% homology between the two species; the extended N-terminal sequences show no homology. The Neurospora protein is characterized by the appearance of the S(T)PXX sequence motif where the amino acid homologies break down. The codon usage is biased in both genes, with a marked deficiency, especially in Neurospora, of codons with A in the third position. The facA transcribed sequence contains six introns: one in the long leader sequence, one in the 5' coding sequence not homologous with acu-5, and four within the sequence that is largely similar to that of acu-5. Only one intron, corresponding in size and position to the furthest downstream of the facA introns, is found in acu-5. The evolution of introns during the divergence of these two Ascomycete fungi is discussed. Each of the two genes has been transferred by transformation into the other species. Each species is evidently able to splice out the other's introns. Most transformants have normal acetate-induction of acetyl-CoA synthetase, implying that the two genes respond to transcriptional control signals common to both species, in spite of the striking divergence of their 5' ends. PMID:1972535

  13. Phylogenetic analysis of LSU and SSU rDNA group I introns of lichen photobionts associated with the genera Xanthoria and Xanthomendoza (Teloschistaceae, lichenized Ascomycetes)

    PubMed Central

    Nyati, Shyam; Bhattacharya, Debashish; Werth, Silke; Honegger, Rosmarie

    2013-01-01

    We studied group I introns in sterile cultures of selected groups of lichen photobionts, focusing on Trebouxia species associated with Xanthoria s. lat. (including Xanthomendoza spp.; lichen-forming ascomycetes). Group I introns were found inserted after position 798 (Escherichia coli numbering) in the large subunit (LSU) rRNA in representatives of the green algal genera Trebouxia and Asterochloris. The 798 intron was found in about 25% of Xanthoria photobionts including several reference strains obtained from algal culture collections. An alignment of LSU-encoded rDNA intron sequences revealed high similarity of these sequences allowing their phylogenetic analysis. The 798 group I intron phylogeny was largely congruent with a phylogeny of the Internal Transcribed Spacer Region (ITS), indicating that the insertion of the intron most likely occurred in the common ancestor of the genera Trebouxia and Asterochloris. The intron was vertically inherited in some taxa, but lost in others. The high sequence similarity of this intron to one found in Chlorella angustoellipsoidea suggests that the 798 intron was either present in the common ancestor of Trebouxiophyceae, or that its present distribution results from more recent horizontal transfers, followed by vertical inheritance and loss. Analysis of another group I intron shared by these photobionts at small subunit (SSU) position 1512 supports the hypothesis of repeated lateral transfers of this intron among some taxa, but loss among others. Our data confirm that the history of group I introns is characterized by repeated horizontal transfers, and suggests that some of these introns have ancient origins within Chlorophyta. PMID:24415800

  14. Pulmonary Necrotizing Granulomas in a patient with familial mediterranean fever.

    PubMed

    Kushima, Hisako; Ishii, Hiroshi; Ishii, Koji; Kadota, Jun-ichi

    2015-09-01

    We herein report a case of familial Mediterranean fever (FMF) presenting with granulomatous lung lesions with neuronal apoptosis inhibitory protein (NAIP), MHC class II transcription activator (CIITA), incompatibility locus protein from Podospora anserina (HET-E), and telomerase-associated protein (TP1) (NACHT) leucine-rich-repeat 1-positive inflammatory cell infiltrates. FMF is an autoinflammatory disorder characterized by recurrent and self-limited attacks of pyrexia, arthritis and erysipelas-like skin lesions. Lung disorders associated with FMF are extremely rare. This is the first report of an immunologically-confirmed case of pulmonary manifestations of this disease. PMID:24252001

  15. Subcutaneous phaeohyphomycosis in a patient with IgG4-related sclerosing disease caused by a novel ascomycete, Hongkongmyces pedis gen. et sp. nov.: first report of human infection associated with the family Lindgomycetaceae.

    PubMed

    Tsang, Chi-Ching; Chan, Jasper F W; Trendell-Smith, Nigel J; Ngan, Antonio H Y; Ling, Ian W H; Lau, Susanna K P; Woo, Patrick C Y

    2014-10-01

    No members of the freshwater ascomycetes family Lindgomycetaceae have been associated with human infections. We isolated a mould (HKU35(T)) from the biopsy specimen of a patient with invasive foot infection and underlying immunoglobulin G4-related sclerosing disease. Histology showed florid, suppurative, granulomatous inflammation in the dermis, with central microabscess formation surrounded by epithelioid histiocytes, scattered giant cells, and a small number of lymphocytes. A Grocott stain revealed fungal elements in the center of the lesion. On Sabouraud glucose agar, HKU35(T) grew as gray and velvety colonies. Among the members of the family Lindgomycetaceae, HKU35(T) was the only strain that grew at 37°C. Microscopically, only sterile mycelia, but no fruiting bodies, were observed. HKU35(T) was susceptible to itrazonazole, voriconazole, and posaconazole, which was in line with the patient's clinical response to itraconazole treatment. Internal transcribed spacer and partial 18S nuclear rDNA (nrDNA), 28S nrDNA, β-tubulin gene, and EF1α gene sequencing showed that HKU35(T) occupied a unique phylogenetic position, most closely related to but distinct from members of the genera Clohesyomyces and Lindgomyces. We propose a new genus and species, Hongkongmyces pedis gen. et sp. nov., to describe this fungus, which belongs to the family Lindgomycetaceae in the orderPleosporales of class Dothideomycetes. This case also represents the first report of human infection associated with the family Lindgomycetaceae. PMID:25147085

  16. Human CLPP reverts the longevity phenotype of a fungal ClpP deletion strain

    PubMed Central

    Fischer, Fabian; Weil, Andrea; Hamann, Andrea; Osiewacz, Heinz D.

    2013-01-01

    Mitochondrial maintenance crucially depends on the quality control of proteins by various chaperones, proteases and repair enzymes. While most of the involved components have been studied in some detail, little is known on the biological role of the CLPXP protease complex located in the mitochondrial matrix. Here we show that deletion of PaClpP, encoding the CLP protease proteolytic subunit CLPP, leads to an unexpected healthy phenotype and increased lifespan of the fungal ageing model organism Podospora anserina. This phenotype can be reverted by expression of human ClpP in the fungal deletion background, demonstrating functional conservation of human and fungal CLPP. Our results show that the biological role of eukaryotic CLP proteases can be studied in an experimentally accessible model organism. PMID:23360988

  17. Prions are affected by evolution at two levels.

    PubMed

    Wickner, Reed B; Kelly, Amy C

    2016-03-01

    Prions, infectious proteins, can transmit diseases or be the basis of heritable traits (or both), mostly based on amyloid forms of the prion protein. A single protein sequence can be the basis for many prion strains/variants, with different biological properties based on different amyloid conformations, each rather stably propagating. Prions are unique in that evolution and selection work at both the level of the chromosomal gene encoding the protein, and on the prion itself selecting prion variants. Here, we summarize what is known about the evolution of prion proteins, both the genes and the prions themselves. We contrast the one known functional prion, [Het-s] of Podospora anserina, with the known disease prions, the yeast prions [PSI+] and [URE3] and the transmissible spongiform encephalopathies of mammals. PMID:26713322

  18. A mitochondrial mutator plasmid that causes senescence under dietary restricted conditions

    PubMed Central

    Maas, Marc FPM; Hoekstra, Rolf F; Debets, Alfons JM

    2007-01-01

    Background Calorie or dietary restriction extends life span in a wide range of organisms including the filamentous fungus Podospora anserina. Under dietary restricted conditions, P. anserina isolates are several-fold longer lived. This is however not the case in isolates that carry one of the pAL2-1 homologous mitochondrial plasmids. Results We show that the pAL2-1 homologues act as 'insertional mutators' of the mitochondrial genome, which may explain their negative effect on life span extension. Sequencing revealed at least fourteen unique plasmid integration sites, of which twelve were located within the mitochondrial genome and two within copies of the plasmid itself. The plasmids were able to integrate in their entirety, via a non-homologous mode of recombination. Some of the integrated plasmid copies were truncated, which probably resulted from secondary, post-integrative, recombination processes. Integration sites were predominantly located within and surrounding the region containing the mitochondrial rDNA loci. Conclusion We propose a model for the mechanism of integration, based on innate modes of mtDNA recombination, and discuss its possible link with the plasmid's negative effect on dietary restriction mediated life span extension. PMID:17407571

  19. Reverse transcriptase activity of an intron encoded polypeptide.

    PubMed Central

    Fassbender, S; Brühl, K H; Ciriacy, M; Kück, U

    1994-01-01

    A number of group II introns from eukaryotic organelles and prokaryotes contain open reading frames for polypeptides with homology to retroviral reverse transcriptases (RTs). We have used the yeast transposon (Ty) system to express ORFs for RTs from eukaryotic organelles. This includes the mitochondrial coxI intron i1 from the fungus Podospora anserina, the plastid petD intron from the alga Scenedesmus obliquus and the mitochondrial RTL gene from the alga Chlamydomonas reinhardtii. The ORFs were fused with the TYA ORF from the yeast retrotransposon Ty to produce virus-like particles in the recipient strains with detectable amounts of the RT-like polypeptides. Analysis of the heterologous gene products revealed biochemical evidence that the P. anserina intron encodes an RNA-directed DNA polymerase with properties typically found for RTs of viral or retrotransposable origin. In vitro assays showed that the intron encoded RT is sensitive to RT inhibitors such as N-ethylmaleimide and dideoxythymidine triphosphate but is insensitive against the DNA polymerase inhibitor aphidicolin. The direct biochemical evidence provided here supports the idea that intron encoded RTs are involved in intron transposition events. Images PMID:7514530

  20. Characterization of the aodA, dnmA, mnSOD and pimA genes in Aspergillus nidulans

    PubMed Central

    Leiter, Éva; Park, Hee-Soo; Kwon, Nak-Jung; Han, Kap-Hoon; Emri, Tamás; Oláh, Viktor; Mészáros, Ilona; Dienes, Beatrix; Vincze, János; Csernoch, László; Yu, Jae-Hyuk; Pócsi, István

    2016-01-01

    Mitochondria play key roles in cellular energy generation and lifespan of most eukaryotes. To understand the functions of four nuclear-encoded genes predicted to be related to the maintenance of mitochondrial morphology and function in Aspergillus nidulans, systematic characterization was carried out. The deletion and overexpression mutants of aodA, dnmA, mnSOD and pimA encoding alternative oxidase, dynamin related protein, manganese superoxide dismutase and Lon protease, respectively, were generated and examined for their growth, stress tolerances, respiration, autolysis, cell death, sterigmatocystin production, hyphal morphology and size, and mitochondrial superoxide production as well as development. Overall, genetic manipulation of these genes had less effect on cellular physiology and ageing in A. nidulans than that of their homologs in another fungus Podospora anserina with a well-characterized senescence. The observed interspecial phenotypic differences can be explained by the dissimilar intrinsic stabilities of the mitochondrial genomes in A. nidulans and P. anserina. Furthermore, the marginally altered phenotypes observed in A. nidulans mutants indicate the presence of effective compensatory mechanisms for the complex networks of mitochondrial defense and quality control. Importantly, these findings can be useful for developing novel platforms for heterologous protein production, or on new biocontrol and bioremediation technologies based on Aspergillus species. PMID:26846452

  1. An Acetyltransferase Conferring Tolerance to Toxic Aromatic Amine Chemicals

    PubMed Central

    Martins, Marta; Rodrigues-Lima, Fernando; Dairou, Julien; Lamouri, Aazdine; Malagnac, Fabienne; Silar, Philippe; Dupret, Jean-Marie

    2009-01-01

    Aromatic amines (AA) are a major class of environmental pollutants that have been shown to have genotoxic and cytotoxic potentials toward most living organisms. Fungi are able to tolerate a diverse range of chemical compounds including certain AA and have long been used as models to understand general biological processes. Deciphering the mechanisms underlying this tolerance may improve our understanding of the adaptation of organisms to stressful environments and pave the way for novel pharmaceutical and/or biotechnological applications. We have identified and characterized two arylamine N-acetyltransferase (NAT) enzymes (PaNAT1 and PaNAT2) from the model fungus Podospora anserina that acetylate a wide range of AA. Targeted gene disruption experiments revealed that PaNAT2 was required for the growth and survival of the fungus in the presence of toxic AA. Functional studies using the knock-out strains and chemically acetylated AA indicated that tolerance of P. anserina to toxic AA was due to the N-acetylation of these chemicals by PaNAT2. Moreover, we provide proof-of-concept remediation experiments where P. anserina, through its PaNAT2 enzyme, is able to detoxify the highly toxic pesticide residue 3,4-dichloroaniline in experimentally contaminated soil samples. Overall, our data show that a single xenobiotic-metabolizing enzyme can mediate tolerance to a major class of pollutants in a eukaryotic species. These findings expand the understanding of the role of xenobiotic-metabolizing enzyme and in particular of NATs in the adaptation of organisms to their chemical environment and provide a basis for new systems for the bioremediation of contaminated soils. PMID:19416981

  2. Fatal cerebral mycoses caused by the ascomycete Chaetomium strumarium.

    PubMed Central

    Abbott, S P; Sigler, L; McAleer, R; McGough, D A; Rinaldi, M G; Mizell, G

    1995-01-01

    Three cases of fatal cerebral mycosis in males with prior histories of intravenous drug use from the United States and Australia are reported. Infection in each case was limited to brain abscess; no other sites of infection were observed. The fungus seen by histopathology and isolated from the brain tissue in each case was identified as Chaetomium strumarium. This is the first report of human infection by this species, and C. strumarium is the second species of Chaetomium known to cause primary brain infection. Chaetomium strumarium is unusual among members of the genus Chaetomium in forming ascocarps covered with pale, thin-walled, flexuous hairs, a feature leading to its original placement in the genus Achaetomium. Presence of pinkish exudate droplets and/or crystals associated with hyphae or ascocarps, sometimes accompanied by a pinkish diffusible pigment; good growth at 42 degrees C; and production of small conidia further distinguish this species. The brain abscess isolates were compared with isolates from prior cases of cerebral infection which had been identified as either Chaetomium atrobrunneum or Chaetomium globosum. With reidentification of one isolate originally identified as C. globosum to C. atrobrunneum, only C. strumarium and C. atrobrunneum have been confirmed to cause infection involving the brain. PMID:8567907

  3. Reclassification of ascomycetous yeasts from gene sequence analyses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During the past decade, identification of yeasts and their classification has been based almost exclusively on gene sequence analysis. Primarily as a result of using diagnostic gene sequences, such as D1/D2 LSU and ITS ribosomal RNAs, the number of known species has doubled. With the faster sequen...

  4. Enzymes and bioproducts produced by the ascomycete fungus Paecilomyces variotii.

    PubMed

    Herrera Bravo de Laguna, I; Toledo Marante, F J; Mioso, R

    2015-12-01

    Due its innate ability to produce extracellular enzymes which can provide eco-friendly solutions for a variety of biotechnological applications, Paecilomyces variotii is a potential source of industrial bioproducts. In this review, we report biotechnological records on the biochemistry of different enzymes produced by the fermentation of the P. variotii fungus, including tannases, phytases, cellulases, xylanases, chitinases, amylases and pectinases. Additionally, the main physicochemical properties which can affect the enzymatic reactions of the enzymes involved in the conversion of a huge number of substrates to high-value bioproducts are described. Despite all the background information compiled in this review, more research is required to consolidate the catalytic efficiency of P. variotii, which must be optimized so that it is more accurate and reproducible on a large scale. PMID:26274842

  5. Ampullosine, a new isoquinoline alkaloid from Sepedonium ampullosporum (Ascomycetes).

    PubMed

    Quang, Dang Ngoc; Schmidt, Jürgen; Porzel, Andrea; Wessjohann, Ludger; Haid, Mark; Arnold, Norbert

    2010-06-01

    A new isoquinoline alkaloid, ampullosine (3-methyl-isoquinoline-6-carboxylic acid, 1), was isolated from Sepedonium ampullosporum and characterized by spectroscopic analysis and chemical reactions. This compound is responsible for the deep yellow color of the culture fluid of this species. Moreover, the known compounds sepedonin (2) and anhydrosepedonin (3) were detected. Twelve strains belonging to eight species of Sepedonium have been screened for these three metabolites by LC/ESI-SRM (selected reaction monitoring). Ampullosine (1) could be detected in almost all species in Sepedonium, but not in the phylogenetically more distant species S. brunneum and S. tulasneanum. Anhydrosepedonin (3) showed antifungal activity against the phytopathogenic fungus Cladosporium cucumerinum. PMID:20614812

  6. Coprophilous fungi of the horse.

    PubMed

    Pointelli, E; Santa-maria, M A; Caretta, G

    1981-05-01

    A total of 1267 microfungi, including 35 Myxomycetes, were recorded from the fecal samples of the 60 horses; of these 395 were found on 20 saddle-horse feces, 363 on 20 race-horses and 509 on 20 working horses. Eighty two species representing 53 genera were recorded; of these 7 were Zygomycetes, 18 Ascomycetes, 1 Basidiomycetes and 25 Fungi Imperfecti: 2 Myxomycetes. Common coprophilous fungi are in decreasing order Pilobolus kleinii, Saccobolus depauperatus, Mucor hiemalis, Lasiobolus ciliatus, Podospora curvula, Petriella guttulata, M. circinelloides, Coprinus radiatus, Dictyostelium mucoroides, Sordaria fimicola, C. miser, C. stercorariusm, Acremonium sp., Coprotus granuliformis, Graphium putredinis, Iodophanus carneus, Chaetomium murorum, Podospora communis, P. inaequalis, P. setosa, Saccobolus versicolor and Cladosporium cucumerinum. Species of Myrothecium verrucaria, Actinomucor elegans, Kernia nitida, Spiculostilbella dendritica and Mucor parvispora were found exclusively in working-horses feces. Badhamia sp., Anixiopsis stercoraria, Echinobotryum state of D. stemonitis, Geotrichum candidum and Oidiodendron sp. were found only in saddle-horses feces. Chlamidomyces palmarum, Philocopra sp. were found exclusively in race-horses feces. Notes on infrequent or interesting fungi include Thamnostylum piriforme, Phialocephala dimorphospora, Rhopalomyces elegans and Spiculostilbella dendritica. PMID:7242651

  7. Peroxisomes and sexual development in fungi

    PubMed Central

    Peraza-Reyes, Leonardo; Berteaux-Lecellier, Véronique

    2013-01-01

    Peroxisomes are versatile and dynamic organelles that are essential for the development of most eukaryotic organisms. In fungi, many developmental processes, such as sexual development, require the activity of peroxisomes. Sexual reproduction in fungi involves the formation of meiotic-derived sexual spores, often takes place inside multicellular fruiting bodies and requires precise coordination between the differentiation of multiple cell types and the progression of karyogamy and meiosis. Different peroxisomal functions contribute to the orchestration of this complex developmental process. Peroxisomes are required to sustain the formation of fruiting bodies and the maturation and germination of sexual spores. They facilitate the mobilization of reserve compounds via fatty acid β-oxidation and the glyoxylate cycle, allowing the generation of energy and biosynthetic precursors. Additionally, peroxisomes are implicated in the progression of meiotic development. During meiotic development in Podospora anserina, there is a precise modulation of peroxisome assembly and dynamics. This modulation includes changes in peroxisome size, number and localization, and involves a differential activity of the protein-machinery that drives the import of proteins into peroxisomes. Furthermore, karyogamy, entry into meiosis and sorting of meiotic-derived nuclei into sexual spores all require the activity of peroxisomes. These processes rely on different peroxisomal functions and likely depend on different pathways for peroxisome assembly. Indeed, emerging studies support the existence of distinct import channels for peroxisomal proteins that contribute to different developmental stages. PMID:24046747

  8. Molecular characterization of a new alkaline-tolerant xylanase from Humicola insolens Y1.

    PubMed

    Shi, Pengjun; Du, Yanlong; Yang, Hong; Huang, Huoqing; Zhang, Xiu; Wang, Yaru; Yao, Bin

    2015-01-01

    An endo-1,4-β-xylanase-encoding gene, xyn11B, was cloned from the thermophilic fungus Humicola insolens Y1. The gene encodes a multimodular xylanase that consists of a typical hydrophobic signal sequence, a catalytic domain of glycoside hydrolase (GH) family 11, a glycine-rich linker, and a family 1 carbohydrate binding module (CBM1). Deduced Xyn11B shares the highest identity of 74% with a putative xylanase from Podospora anserina S mat+. Recombinant Xyn11B was successfully expressed in Pichia pastoris and purified to electrophoretic homogeneity. Xyn11B had a high specific activity of 382.0 U mg(-1) towards beechwood xylan and showed optimal activity at pH 6.0 and 50°C. Distinct from most reported acidic fungal xylanases, Xyn11B was alkaline-tolerant, retaining 30.7% of the maximal activity at pH 9.0. The K m and V max values for beechwood xylan were 2.2 mg mL(-1) and 462.8 μmol min(-1) mg(-1), respectively. The enzyme exhibited a wider substrate specificity and produced a mixture of xylooligosaccharides. All these favorable enzymatic properties make Xyn11B attractive for potential applications in various industries. PMID:25629035

  9. A mitotically inheritable unit containing a MAP kinase module

    PubMed Central

    Kicka, Sébastien; Bonnet, Crystel; Sobering, Andrew K.; Ganesan, Latha P.; Silar, Philippe

    2006-01-01

    Prions are novel kinds of hereditary units, relying solely on proteins, that are infectious and inherited in a non-Mendelian fashion. To date, they are either based on autocatalytic modification of a 3D conformation or on autocatalytic cleavage. Here, we provide further evidence that in the filamentous fungus Podospora anserina, a MAP kinase cascade is probably able to self-activate and generate C, a hereditary unit that bears many similarities to prions and triggers cell degeneration. We show that in addition to the MAPKKK gene, both the MAPKK and MAPK genes are necessary for the propagation of C, and that overexpression of MAPK as that of MAPKKK facilitates the appearance of C. We also show that a correlation exists between the presence of C and localization of the MAPK inside nuclei. These data emphasize the resemblance between prions and a self-positively regulated cascade in terms of their transmission. This thus further expands the concept of protein-base inheritance to regulatory networks that have the ability to self-activate. PMID:16938837

  10. Biotransformation of Trichoderma spp. and Their Tolerance to Aromatic Amines, a Major Class of Pollutants

    PubMed Central

    Cocaign, Angélique; Bui, Linh-Chi; Silar, Philippe; Chan Ho Tong, Laetitia; Busi, Florent; Lamouri, Aazdine; Mougin, Christian; Rodrigues-Lima, Fernando

    2013-01-01

    Trichoderma spp. are cosmopolitan soil fungi that are highly resistant to many toxic compounds. Here, we show that Trichoderma virens and T. reesei are tolerant to aromatic amines (AA), a major class of pollutants including the highly toxic pesticide residue 3,4-dichloroaniline (3,4-DCA). In a previous study, we provided proof-of-concept remediation experiments in which another soil fungus, Podospora anserina, detoxifies 3,4-DCA through its arylamine N-acetyltransferase (NAT), a xenobiotic-metabolizing enzyme that enables acetyl coenzyme A-dependent detoxification of AA. To assess whether the N-acetylation pathway enables AA tolerance in Trichoderma spp., we cloned and characterized NATs from T. virens and T. reesei. We characterized recombinant enzymes by determining their catalytic efficiencies toward several toxic AA. Through a complementary approach, we also demonstrate that both Trichoderma species efficiently metabolize 3,4-DCA. Finally, we provide evidence that NAT-independent transformation is solely (in T. virens) or mainly (in T. reesei) responsible for the observed removal of 3,4-DCA. We conclude that T. virens and, to a lesser extent, T. reesei likely utilize another, unidentified, metabolic pathway for the detoxification of AA aside from acetylation. This is the first molecular and functional characterization of AA biotransformation in Trichoderma spp. Given the potential of Trichoderma for cleanup of contaminated soils, these results reveal new possibilities in the fungal remediation of AA-contaminated soil. PMID:23728813

  11. Neurospora crassa mat A-2 and mat A-3 proteins weakly interact in the yeast two-hybrid system and affect yeast growth

    PubMed Central

    2009-01-01

    Mating-type genes control the entry into the sexual cycle, mating identity and sexual development in fungi. The mat A-2 and mat A-3 genes, present in the mat A idiomorph of the filamentous fungus Neurospora crassa, are required for post-fertilization functions but are not essential for mating identity. Their putative roles as transcription factors are based on the similarity of mat A-2 with the Podospora anserina SMR1 gene and an HMG motif present in the mat A-3 gene. In this work the yeast two-hybrid system was used to identify transcriptional activity and protein-protein interaction of N. crassamat A-2 and mat A-3 genes. We observed that the mat A-3 protein alone is capable of weakly activating transcription of yeast reporter genes; it also binds with low specificity to the GAL1 promoter sequence, possibly due to its HMG domain. Our results also indicate that mat A-3 is capable to form homodimers, and interact with mat A-2. Interference on yeast growth was observed on some transformants suggesting a toxic action of the mat A-2 protein. Our data on pattern of interactions of mat proteins contributes towards understanding the control of vegetative and sexual cycles in filamentous fungi. PMID:21637691

  12. The Pichia pastoris PER6 gene product is a peroxisomal integral membrane protein essential for peroxisome biogenesis and has sequence similarity to the Zellweger syndrome protein PAF-1.

    PubMed Central

    Waterham, H R; de Vries, Y; Russel, K A; Xie, W; Veenhuis, M; Cregg, J M

    1996-01-01

    We report the cloning of PER6, a gene essential for peroxisome biogenesis in the methylotrophic yeast Pichia pastoris. The PER6 sequence predicts that its product Per6p is a 52-kDa polypeptide with the cysteine-rich C3HC4 motif. Per6p has significant overall sequence similarity with the human peroxisome assembly factor PAF-1, a protein that is defective in certain patients suffering from the peroxisomal disorder Zellweger syndrome, and with car1, a protein required for peroxisome biogenesis and caryogamy in the filamentous fungus Podospora anserina. In addition, the C3HC4 motif and two of the three membrane-spanning segments predicted for Per6p align with the C3HC4 motifs and the two membrane-spanning segments predicted for PAF-1 and car1. Like PAF-1, Per6p is a peroxisomal integral membrane protein. In methanol- or oleic acid-induced cells of per6 mutants, morphologically recognizable peroxisomes are absent. Instead, peroxisomal remnants are observed. In addition, peroxisomal matrix proteins are synthesized but located in the cytosol. The similarities between Per6p and PAF-1 in amino acid sequence and biochemical properties, and between mutants defective in their respective genes, suggest that Per6p is the putative yeast homolog of PAF-1. PMID:8628321

  13. RCF1-dependent respiratory supercomplexes are integral for lifespan-maintenance in a fungal ageing model

    PubMed Central

    Fischer, Fabian; Filippis, Christodoulos; Osiewacz, Heinz D.

    2015-01-01

    Mitochondrial respiratory supercomplexes (mtRSCs) are stoichiometric assemblies of electron transport chain (ETC) complexes in the inner mitochondrial membrane. They are hypothesized to regulate electron flow, the generation of reactive oxygen species (ROS) and to stabilize ETC complexes. Using the fungal ageing model Podospora anserina, we investigated the impact of homologues of the Saccharomyces cerevisiae respiratory supercomplex factors 1 and 2 (termed PaRCF1 and PaRCF2) on mtRSC formation, fitness and lifespan. Whereas PaRCF2’s role seems negligible, ablation of PaRCF1 alters size of monomeric complex IV, reduces the abundance of complex IV-containing supercomplexes, negatively affects vital functions and shortens lifespan. PaRcf1 overexpression slightly prolongs lifespan, though without appreciably influencing ETC organization. Overall, our results identify PaRCF1 as necessary yet not sufficient for mtRSC formation and demonstrate that PaRCF1-dependent stability of complex IV and associated supercomplexes is highly relevant for maintenance of the healthy lifespan in a eukaryotic model organism. PMID:26220011

  14. Identification of potential mitochondrial CLPXP protease interactors and substrates suggests its central role in energy metabolism

    PubMed Central

    Fischer, Fabian; Langer, Julian D.; Osiewacz, Heinz D.

    2015-01-01

    Maintenance of mitochondria is achieved by several mechanisms, including the regulation of mitochondrial proteostasis. The matrix protease CLPXP, involved in protein quality control, has been implicated in ageing and disease. However, particularly due to the lack of knowledge of CLPXP’s substrate spectrum, only little is known about the pathways and mechanisms controlled by this protease. Here we report the first comprehensive identification of potential mitochondrial CLPXP in vivo interaction partners and substrates using a combination of tandem affinity purification and differential proteomics. This analysis reveals that CLPXP in the fungal ageing model Podospora anserina is mainly associated with metabolic pathways in mitochondria, e.g. components of the pyruvate dehydrogenase complex and the tricarboxylic acid cycle as well as subunits of electron transport chain complex I. These data suggest a possible function of mitochondrial CLPXP in the control and/or maintenance of energy metabolism. Since bioenergetic alterations are a common feature of neurodegenerative diseases, cancer, and ageing, our data comprise an important resource for specific studies addressing the role of CLPXP in these adverse processes. PMID:26679294

  15. Theme and variations: evolutionary diversification of the HET-s functional amyloid motif

    PubMed Central

    Daskalov, Asen; Dyrka, Witold; Saupe, Sven J.

    2015-01-01

    In mammals and fungi, Nod-like receptors (NLR) activate downstream cell death execution proteins by a prion-like mechanism. In Podospora anserina, the NWD2 NLR activates the HET-S Helo-domain pore-forming protein by converting its prion-forming domain into a characteristic β-solenoid amyloid fold. The amyloid forming region of HET-S/s comprises two repetitions of a 21 amino acid motif. Herein, we systematically analyze the sequences of C-terminal regions of fungal HeLo and HeLo-like domain proteins to identify HET-s-related amyloid motifs (HRAM). We now identify four novel HRAM subfamilies in addition to the canonical HET-S/s subfamily. These novel motifs share the pseudo-repeat structure of HET-S/s and a specific pattern of distribution of hydrophobic and polar residues. Sequence co-variance analyses predict parallel in-register β-stacking of the two repeats and residue-residue interactions compatible with the β-solenoid fold. As described for HET-S, most genes encoding the HeLo proteins are adjacent to genes encoding NLRs also displaying HRAMs. The motifs of the NLRs are similar to those of their cognate HeLo-domain protein, indicating concerted evolution between repeats. This study shows that HET-s-related amyloid motifs are more common than anticipated and that they have diversified into discrete subfamilies that apparently share a common overall fold. PMID:26219477

  16. Identification of a family of bacteriophage T4 genes encoding proteins similar to those present in group I introns of fungi and phage.

    PubMed Central

    Sharma, M; Ellis, R L; Hinton, D M

    1992-01-01

    The bacteriophage T4 segA gene lies in a genetically unmapped region between the gene beta gt (beta-glucosyltransferase) and uvsX (recombination protein) and encodes a protein of 221 amino acids. We have found that the first 100 amino acids of the SegA protein are highly similar to the N termini of four other predicted T4 proteins, also of unknown function. Together these five proteins, SegA-E (similar to endonucleases of group I introns), contain regions of similarity to the endonuclease I-Tev I, which is encoded by the mobile group I intron of the T4 td gene, and to putative endonucleases of group I introns present in the mitochondria of Neurospora crassa, Podospora anserina, and Saccharomyces douglasii. Intron-encoded endonucleases are required for the movement (homing) of the intron DNA into an intronless gene, cutting at or near the site of intron insertion. Our in vitro assays indicate that SegA, like I-Tev I, is a Mg(2+)-dependent DNA endonuclease that has preferred sites for cutting. Unlike the I-Tev I gene, however, there is no evidence that segA (or the other seg genes) resides within introns. Thus, it is possible that segA encodes an endonuclease that is involved in the movement of the endonuclease-encoding DNA rather than in the homing of an intron. Images PMID:1631169

  17. [Compatibility of Beauveria bassiana (Ascomycetes: Clavicipitaceae) with chemicals acaricides used in the control of cattle tick].

    PubMed

    Barci, Leila A G; Wenzel, Inajá M; de Almeida, José Eduardo M; de Campos Nogueira, Adriana H; do Prado, Angelo P

    2009-12-01

    The purpose of the present study was to assess compatibility between IBCB66 and IBCB21 isolates of Beauveria bassiana and acaricides: Flumethrin+Coumaphos, Deltamethrin, Dichlorvos+Cypermethrin, Dichlorvos+Chlorpyrifos, Cypermethrin High Cis, Dichlorvos+Cypermethrin High Cis, Cypermethrin and Amitraz, utilized on the control of Rhipicephalus (Boophilus) microplus in our country. The effect of commercial products on the isolates was assayed according to observation of vegetative growth, conidia production, and viability of strains of B. bassiana fungus. With concerning about IBCB66 isolate, products Deltamethrin, Cypermethrin High Cis and Amitraz were compatible, not affecting the entomopathogen development. Product Cypermethrin was toxic, and products Flumethrin+Coumaphos, Dichlorvos+Cypermethrin, Dichlorvos+Chlorpyrifos and Dichlorvos+Cypermethrin High Cis were very toxic. In regard to IBCB21 isolate, products Flumethrin+Coumaphos, Dichlorvos+Cypermethrin, Dichlorvos+Chlorpyrifos, Cypermethrin High Cis, Dichlorvos+Cypermethrin High Cis and Cypermethrin were very toxic and product Amitraz was toxic. From the acaricides evaluated, product Deltamethrin was the single agent that did not produce toxic effect on the entomopathogen. PMID:20040194

  18. Colonization of roots of cultivated Solanum lycopersicum by dark septate and other ascomycetous endophytes.

    PubMed

    Andrade-Linares, Diana Rocio; Grosch, Rita; Franken, Philipp; Rexer, Karl-Heinz; Kost, Gerhard; Restrepo, Silvia; de Garcia, Maria Caridad Cepero; Maximova, Eugenia

    2011-01-01

    Tomato (Solanum lycopersicum L.) roots from four different crop sites in Colombia were surface sterilized and 51 fungal isolates were obtained and conserved for further analysis. Based on microscopical observations and growth characteristics, 20 fungal isolates corresponded to genus Fusarium, six presented asexual conidia different from Fusarium, eight were sterile mycelia, seven of which had dark septate hyphae and 17 did not continue to grow on plates after being recovered from conservation. Growth on different media, detailed morphological characterization and ITS region sequencing of the six sporulating and eight sterile isolates revealed that they belonged to different orders of Ascomycota and that the sterile dark septate endophytes did not correspond to the well known Phialocephala group. Interactions of nine isolates with tomato plantlets were assessed in vitro. No effect on shoot development was revealed, but three isolates caused brown spots in roots. Colonization patterns as analyzed by confocal microscopy differed among the isolates and ranged from epidermal to cortical penetration. Altogether 11 new isolates from root endophytic fungi were obtained, seven of which showed features of dark septate endophytes. Four known morphotypes were represented by five isolates, while six isolates belonged to five morphotypes of putative new unknown species. PMID:21307164

  19. Keratitis due to the wood saprobic ascomycete, Auerswaldia lignicola (Family Botryosphaeriaceae), in a carpenter in India.

    PubMed

    Ruban, Vasanthakumar Vasantha; Kaliamurthy, Jayaraman; Dineshkumar, Muniyandi; Jesudasan, Christadoss Arul Nelson; Geraldine, Pitchairaj; Thomas, Philip Aloysius

    2013-12-01

    Keratitis due to Auerswaldia lignicola in a 32-year-old Indian male carpenter is described. At presentation, the patient reported persistent pain and tearing (left eye) in spite of topical antimicrobial therapy for more than 3 weeks. Clinically, mycotic keratitis was suspected, and direct microscopy of corneal scrapings stained by lactophenol cotton blue and Gram stains revealed broad septate hyphae. Intensive topical antifungal therapy was then given for 15 days. The keratitis continued to progress, necessitating therapeutic penetrating keratoplasty. Following the keratoplasty, there was rapid reduction in inflammation and gradual quietening of the eye. Brown-black fungal colonies resembling Lasiodiplodia theobromae were isolated from corneal scrape and corneal button (post-surgery) material on Sabouraud glucose-neopeptone agar; however, sporulation did not occur, so the morphological identification could not be confirmed. Sequence analysis of the 18S rRNA region of extracted fungal genomic DNA yielded an identification of A. lignicola Ariyawansa, J.K. Liu & K.D. Hyde; the sequence data have been deposited in GenBank (A. lignicola strain DK/V4, accession number KC866317.1). Medical management of keratitis due to such rarely reported fungal species may be difficult, necessitating surgical procedures. PMID:24158617

  20. Evaluation of Mycelial Nutrients, Bioactive Compounds, and Antioxidants of Five Himalayan Entomopathogenic Ascomyceteous Fungi from India.

    PubMed

    Sharma, Sapan Kumar; Gautam, Nandini; Atri, Narender Singh

    2015-01-01

    In this study, using standard methods, mycelial nutrients, bioactive compounds, and antioxidants were analyzed for the first time for five fungal species: Isaria sinclairii (Berk.) Lloyd, I. tenuipes Peck, I. japonica Yasuda, I. farinosa (Holmsk) Fr. and Cordyceps tuberculata (Lebert) Maire. All of these species were low in fat content and rich in protein, fiber, ash, and carbohydrates. Mineral elements (Fe, Mg, Cu, Mn, and Ca) were detected in appreciable amounts. All three types of fatty acids (saturated, monounsaturated, and polyunsaturated) as well as bioactive compounds (ascorbic acid, β-carotene, lycopene, phenolic compounds, and polysaccharides) were detected for each species. The investigated species showed high ferric-reducing antioxidant power as well as 2,2-diphenyl-1-picryl-hydrazyl radical scavenging activity. Although differences were observed in the values of each species, each species showed richness in one or more components. PMID:26559700

  1. Functional Analyses of Two Acetyl Coenzyme A Synthetases in the Ascomycete Gibberella zeae ▿ †

    PubMed Central

    Lee, Seunghoon; Son, Hokyoung; Lee, Jungkwan; Min, Kyunghun; Choi, Gyung Ja; Kim, Jin-Cheol; Lee, Yin-Won

    2011-01-01

    Acetyl coenzyme A (acetyl-CoA) is a crucial metabolite for energy metabolism and biosynthetic pathways and is produced in various cellular compartments with spatial and temporal precision. Our previous study on ATP citrate lyase (ACL) in Gibberella zeae revealed that ACL-dependent acetyl-CoA production is important for histone acetylation, especially in sexual development, but is not involved in lipid synthesis. In this study, we deleted additional acetyl-CoA synthetic genes, the acetyl-CoA synthetases (ACS genes ACS1 and ACS2), to identify alternative acetyl-CoA production mechanisms for ACL. The ACS1 deletion resulted in a defect in sexual development that was mainly due to a reduction in 1-palmitoyl-2-oleoyl-3-linoleoyl-rac-glycerol production, which is required for perithecium development and maturation. Another ACS coding gene, ACS2, has accessorial functions for ACS1 and has compensatory functions for ACL as a nuclear acetyl-CoA producer. This study showed that acetate is readily generated during the entire life cycle of G. zeae and has a pivotal role in fungal metabolism. Because ACSs are components of the pyruvate-acetaldehyde-acetate pathway, this fermentation process might have crucial roles in various physiological processes for filamentous fungi. PMID:21666077

  2. WetA is required for conidiogenesis and conidium maturation in the ascomycete fungus Fusarium graminearum.

    PubMed

    Son, Hokyoung; Kim, Myung-Gu; Min, Kyunghun; Lim, Jae Yun; Choi, Gyung Ja; Kim, Jin-Cheol; Chae, Suhn-Kee; Lee, Yin-Won

    2014-01-01

    Fusarium graminearum, a prominent fungal pathogen that infects major cereal crops, primarily utilizes asexual spores to spread disease. To understand the molecular mechanisms underlying conidiogenesis in F. graminearum, we functionally characterized the F. graminearum ortholog of Aspergillus nidulans wetA, which has been shown to be involved in conidiogenesis and conidium maturation. Deletion of F. graminearum wetA did not alter mycelial growth, sexual development, or virulence, but the wetA deletion mutants produced longer conidia with fewer septa, and the conidia were sensitive to acute stresses, such as oxidative stress and heat stress. Furthermore, the survival rate of aged conidia from the F. graminearum wetA deletion mutants was reduced. The wetA deletion resulted in vigorous generation of single-celled conidia through autophagy-dependent microcycle conidiation, indicating that WetA functions to maintain conidial dormancy by suppressing microcycle conidiation in F. graminearum. Transcriptome analyses demonstrated that most of the putative conidiation-related genes are expressed constitutively and that only a few genes are specifically involved in F. graminearum conidiogenesis. The conserved and distinct roles identified for WetA in F. graminearum provide new insights into the genetics of conidiation in filamentous fungi. PMID:24186953

  3. Insect peptide metchnikowin confers on barley a selective capacity for resistance to fungal ascomycetes pathogens

    PubMed Central

    Rahnamaeian, Mohammad; Langen, Gregor; Imani, Jafargholi; Khalifa, Walaa; Altincicek, Boran; von Wettstein, Diter; Kogel, Karl-Heinz; Vilcinskas, Andreas

    2009-01-01

    The potential of metchnikowin, a 26-amino acid residue proline-rich antimicrobial peptide synthesized in the fat body of Drosophila melanogaster was explored to engineer disease resistance in barley against devastating fungal plant pathogens. The synthetic peptide caused strong in vitro growth inhibition (IC50 value ∼1 μM) of the pathogenic fungus Fusarium graminearum. Transgenic barley expressing the metchnikowin gene in its 52-amino acid pre-pro-peptide form under the control of the inducible mannopine synthase (mas) gene promoter from the Ti plasmid of Agrobacterium tumefaciens displayed enhanced resistance to powdery mildew as well as Fusarium head blight and root rot. In response to these pathogens, metchnikowin accumulated in plant apoplastic space, specifying that the insect signal peptide is functional in monocotyledons. In vitro and in vivo tests revealed that the peptide is markedly effective against fungal pathogens of the phylum Ascomycota but, clearly, less active against Basidiomycota fungi. Importantly, germination of the mutualistic basidiomycete mycorrhizal fungus Piriformospora indica was affected only at concentrations beyond 50 μM. These results suggest that antifungal peptides from insects are a valuable source for crop plant improvements and their differential activities toward different phyla of fungi denote a capacity for insect peptides to be used as selective measures on specific plant diseases. PMID:19734262

  4. Caterpillar Mushroom, Ophiocordyceps sinensis (Ascomycetes): A Potential Bioresource for Commercialization in Sikkim Himalaya, India.

    PubMed

    Pradhan, Bharat Kumar

    2016-01-01

    Ophiocordyceps sinensis has a long history of use in Tibetan traditional medicine and traditional Chinese medicine as a powerful tonic and aphrodisiac. The species is inextricably linked to the trade of medicinal and aromatic plants in East Asia. Its demand has increased substantially in the international market, and its collection and trade have significantly improved the socioeconomic status of the people in some regions. Nonetheless, in Sikkim this resource is still untapped formally, but it is traded illegally. Formal legalization and the community's involvement will ensure the conservation and sustainability of the species, as well as proper management of harvesting areas and monitoring of pressure on Yartsa Gunbu to exploit it. PMID:27481300

  5. Venturia chinensis sp. nov., a new venturialean ascomycete from Khingan Mountains.

    PubMed

    Zhang, Jiaqi; Dou, Zhipeng; Zhou, Yupei; He, Wei; Zhang, Xiaodong; Zhang, Ying

    2016-09-01

    A new species of Venturia (V. chinensis) is described and illustrated from the leaves of Lonicera praeflorens collected from Lesser Khingan Mountains, the northeast China. It is characterized by habitat saprobic; ascomata small-sized, solitary or scattered, superficial, subglobose to citriform, wall black, papillate, ostiolate, covered with setae; peridium thin; hamathecium evanescent in mature ascomata; asci 8-spored, bitunicate, fissitunicate, oblong to obclavate, with or without a short, knob-like pedicel; ascospores ellipsoidal, olivaceous pale brown, 1-septate, ascospore wall thin, smooth. Comparisons of V. chinensis with V. lonicerae (another species on Lonicera caerulea) and other species of Venturia lead to the conclusion that collected taxon is new. Its relationships with other species of Venturia are discussed based on morphology and 28S nrDNA and ITS nrDNA sequence comparisons. PMID:27579008

  6. Fruiting Body Production of the Medicinal Chinese Caterpillar Mushroom, Ophiocordyceps sinensis (Ascomycetes), in Artificial Medium.

    PubMed

    Cao, Li; Ye, Yunshou; Han, Richou

    2015-01-01

    Ophiocordyceps sinensis (syn. Cordyceps sinensis), regarded as the "Himalayan Viagra", is widely used for medicinal treatment and health foods. The price of O. sinensis has continued to increase over the past few years because of the growing worldwide demand and resource limitations. Artificial cultivation of the fruiting bodies to substitute natural O. sinensis is urgently needed for the effective protection of a valuable bioresource and environment in the Tibetan plateau, and for commercial trade. In this study, the anamorph of 3 isolates was separated from natural O. sinensis and identified by molecular markers as Hirsutella sinensis. These fungal isolates were cultured in a rice-based medium at 9-13 °C for 50 days for mycelial growth, at 4 °C for 100 days for stromatal induction, and at 13 °C for 40 days for fruiting body formation. The mature fruiting bodies with mature perithecium were harvested in about 140 days. This is, to our knowledge, the first report of stable fruiting body production of O. sinensis by artificial media in the low-altitude area outside the Tibetan plateau. PMID:26853966

  7. Three types of geranylgeranyl diphosphate synthases from the medicinal caterpillar fungus, Cordyceps militaris (Ascomycetes).

    PubMed

    Lian, Tiantian; Dong, Cai-Hong; Yang, Tao; Sun, Junde

    2014-01-01

    Geranylgeranyl diphosphate synthase (GGPPS) is a key enzyme in the carotenoid biosynthetic pathway, catalyzing the synthesis of its C20 precursor. In the present study, three types of ggpps genes were cloned and analyzed from the Caterpillar Medicinal Fungus Cordyceps militaris, a valued carotenoid-producing species. The sequences were named as ggpps727, ggpps191, and ggpps595. The open reading frame codes for predicted polypeptides of 464, 550, and 431 aa. Three predicted GGPPSs had a high similarity to that from Beauveria bassiana ARSEF 2860 with identity of 73%, 71%, and 56%, respectively. Homology comparison of the deduced peptide sequences of the various GGPPSs revealed highly conserved domains. Both GGPPS727 and GGPPS191 from C. militaris contained all five domains highly conserved among prenyltransferases as well as two aspartate-rich DDXX(XX)D motifs in domains II and V, which have been proven essential for prenyltransferase activity. By constructing the phylogenetic tree of fungal GGPPSs, it was found that fungi-derived GGPPSs could be divided into three clusters, suggesting there were three types of GGPPSs in fungi. Each type may be responsible for a different metabolism. Three types of GGPPSs from C. militaris belonged to the different clusters separately. Expression analysis of three ggpps genes during the fruit body cultivation of C. militaris by real-time polymerase chain reaction (PCR) suggested the ggpps 191 gene may be involved in the synthesis of carotenoids and ggpps 727 may be responsible for primary metabolism. This is the first report of the GGPPS from C. militaris, a valued edible and medicinal fungus. PMID:24941033

  8. Process optimization for extraction of carotenoids from medicinal caterpillar fungus, Cordyceps militaris (Ascomycetes).

    PubMed

    Yang, Tao; Sun, Junde; Lian, Tiantian; Wang, Wenzhao; Dong, Cai-Hong

    2014-01-01

    Natural carotenoids have attracted great attention for their important beneficial effects on human health and food coloring function. Cordyceps militaris, a well-known edible and medicinal fungus, is a potential source of natural carotenoids. The present study aimed to optimize the process parameters for carotenoid extraction from this mushroom. The effects of different methods of breaking the fungal cell wall and organic solvents were studied by the one-factor-at-a-time method. Subsequently, the process parameters including the duration of the extraction time, the number of extractions, and the solvent to solid ratio were optimized by using the Box-Behnken design. The optimal extraction conditions included using an acid-heating method to break the cell wall and later extracting three times, each for a 1 h duration, with a 4:1 mixture of acetone: petroleum ether and a solvent: solid ratio of 24:1. The carotenoid content varied from 2122.50 to 3847.50 µg/g dry weights in different commercially obtained fruit bodies of C. militaris. The results demonstrated that the C. militaris contained more carotenoid content in its fruit bodies than other known mushrooms. Stability monitoring by HPLC demonstrated that the carotenoids could be stored at 4°C for 40 d. It is suggested that the carotenoid content should be considered as the quality standard of commercial products of this valued mushroom. These findings will facilitate the exploration of carotenoids from C. militaris. PMID:24941034

  9. The artificial cultivation of medicinal Caterpillar Fungus, Ophiocordyceps sinensis (Ascomycetes): a review.

    PubMed

    Yue, Kai; Ye, Meng; Lin, Xiao; Zhou, Zuji

    2013-01-01

    Caterpillar fungus, Ophiocordyceps sinensis (syn. Cordyceps sinensis), is highly valued in China as a dietary supplement or tonic food and natural remedy. The combination of the fungus and dead insect has been used as a traditional Chinese medicine for centuries, and evidence shows its efficacy on immunomodulatory potentials. The price of O. sinensis has continued to increase over the last few years due to growing worldwide demand, driving research to determine methods of artificial cultivation to make O. sinensis a more affordable material for commercial trade. This study highlights many aspects of artificial cultivation of O. sinensis, including separation of the anamorph, culture of the mycelium, cultivation of the fruiting bodies, bioecological characteristics of the host insect, and two patterns of artificial cultivation. In addition, this review discusses the current state, limitations, remedies, and future prospects, aiming to draw researchers' attention to the new frontier of research needs in this context. PMID:24266368

  10. Starmerella meliponinorum sp. nov., a novel ascomycetous yeast species associated with stingless bees.

    PubMed

    Teixeira, Ana C P; Marini, Marjorie M; Nicoli, Jacques R; Antonini, Yasmine; Martins, Rogerio P; Lachance, Marc-André; Rosa, Carlos A

    2003-01-01

    Thirty-two strains of the novel species Starmerella meliponinorum sp. nov. were isolated from various substrates associated with three stingless bee species (tribe Meliponini) in Brazil and one in Costa Rica. The strains were found in garbage pellets (faecal material, discarded pollen or food, etc.), pollen provisions, adult bees, honey and propolis of Tetragonisca angustula, in honey from Melipona quadritasciata and in adults of Melipona rufiventris and Trigona fulviventris. The sequence of the D1/D2 domains of the large-subunit rDNA showed that the novel species belongs to the Starmerella clade and is most closely related to Candida etchellsii, although the two differ in their sequences by 7% base substitutions. S. meliponinorum is homothallic and assimilates few carbon sources. Nitrate is utilized as a sole nitrogen source. The type strain of S. meliponinorum is strain UFMG-01-J26.1T (=CBS 9117T). PMID:12656193

  11. Biosynthetic investigation of phomopsins reveals a widespread pathway for ribosomal natural products in Ascomycetes.

    PubMed

    Ding, Wei; Liu, Wan-Qiu; Jia, Youli; Li, Yongzhen; van der Donk, Wilfred A; Zhang, Qi

    2016-03-29

    Production of ribosomally synthesized and posttranslationally modified peptides (RiPPs) has rarely been reported in fungi, even though organisms of this kingdom have a long history as a prolific source of natural products. Here we report an investigation of the phomopsins, antimitotic mycotoxins. We show that phomopsin is a fungal RiPP and demonstrate the widespread presence of a pathway for the biosynthesis of a family of fungal cyclic RiPPs, which we term dikaritins. We characterize PhomM as an S-adenosylmethionine-dependent α-N-methyltransferase that converts phomopsin A to anN,N-dimethylated congener (phomopsin E), and show that the methyltransferases involved in dikaritin biosynthesis have evolved differently and likely have broad substrate specificities. Genome mining studies identified eight previously unknown dikaritins in different strains, highlighting the untapped capacity of RiPP biosynthesis in fungi and setting the stage for investigating the biological activities and unknown biosynthetic transformations of this family of fungal natural products. PMID:26979951

  12. Mesosynteny; A novel mode of chromosomal evolution peculiar to filamentous Ascomycete fungi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We report a novel form of evolution in which genes are conserved within homologous chromosomes, but with randomised orders and orientations. We propose to call this mode of evolution 'mesosynteny'. Mesosynteny is an alternative evolutionary pathway to macrosyntenic conservation. Mesosynteny would ...

  13. The Ascomycete Verticillium longisporum Is a Hybrid and a Plant Pathogen with an Expanded Host Range

    PubMed Central

    Inderbitzin, Patrik; Davis, R. Michael; Bostock, Richard M.; Subbarao, Krishna V.

    2011-01-01

    Hybridization plays a central role in plant evolution, but its overall importance in fungi is unknown. New plant pathogens are thought to arise by hybridization between formerly separated fungal species. Evolution of hybrid plant pathogens from non-pathogenic ancestors in the fungal-like protist Phytophthora has been demonstrated, but in fungi, the most important group of plant pathogens, there are few well-characterized examples of hybrids. We focused our attention on the hybrid and plant pathogen Verticillium longisporum, the causal agent of the Verticillium wilt disease in crucifer crops. In order to address questions related to the evolutionary origin of V. longisporum, we used phylogenetic analyses of seven nuclear loci and a dataset of 203 isolates of V. longisporum, V. dahliae and related species. We confirmed that V. longisporum was diploid, and originated three different times, involving four different lineages and three different parental species. All hybrids shared a common parent, species A1, that hybridized respectively with species D1, V. dahliae lineage D2 and V. dahliae lineage D3, to give rise to three different lineages of V. longisporum. Species A1 and species D1 constituted as yet unknown taxa. Verticillium longisporum likely originated recently, as each V. longisporum lineage was genetically homogenous, and comprised species A1 alleles that were identical across lineages. PMID:21455321

  14. Two new pathogenic ascomycetes in Guignardia and Rosenscheldiella on New Zealand's pygmy mistletoes (Korthalsella: Viscaceae)

    PubMed Central

    Sultan, A.; Johnston, P.R.; Park, D.; Robertson, A.W.

    2011-01-01

    Two new pathogens, Guignardia korthalsellae and Rosenscheldiella korthalsellae, are described from New Zealand's pygmy mistletoes (Korthalsella, Viscaceae). Both form ascomata on living phylloclades with minimal disruption of the tissue. Fungal hyphae within the phylloclade are primarily intercellular. Guignardia korthalsellae disrupts a limited number of epidermal cells immediately around the erumpent ascoma, while the ascomata of Rosenscheldiella korthalsellae develop externally on small patches of stromatic tissue that form above stomatal cavities. Rosenscheldiella is applied in a purely morphological sense. LSU sequences show that R. korthalsellae as well as another New Zealand species, Rosenscheldiella brachyglottidis, are members of the Mycosphaerellaceae sensu stricto. Genetically, Rosenscheldiella, in the sense we are using it, is polyphyletic; LSU and ITS sequences place the two New Zealand species in different clades within the Mycosphaerellaceae. Rosenscheldiella is retained for these fungi until generic relationships within the family are resolved. Whether or not the type species of Rosenscheldiella, R. styracis, is also a member of the Mycosphaerellaceae is not known, but it has a similar morphology and relationship to its host as the two New Zealand species. PMID:21523197

  15. A new endophytic ascomycete from El Eden Ecological Reserve, Quintana Roo, Mexico

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During a preliminary survey to report the biodiversity of endophytic fungi associated with leaves of some woody plants from El Eden Ecological Reserve in Mexico, a new fungus was isolated from Callicarpa acuminata leaves. Cultures of this fungus on PDA form a white floccose colony with a reddish-bro...

  16. WetA Is Required for Conidiogenesis and Conidium Maturation in the Ascomycete Fungus Fusarium graminearum

    PubMed Central

    Son, Hokyoung; Kim, Myung-Gu; Min, Kyunghun; Lim, Jae Yun; Choi, Gyung Ja; Kim, Jin-Cheol; Chae, Suhn-Kee

    2014-01-01

    Fusarium graminearum, a prominent fungal pathogen that infects major cereal crops, primarily utilizes asexual spores to spread disease. To understand the molecular mechanisms underlying conidiogenesis in F. graminearum, we functionally characterized the F. graminearum ortholog of Aspergillus nidulans wetA, which has been shown to be involved in conidiogenesis and conidium maturation. Deletion of F. graminearum wetA did not alter mycelial growth, sexual development, or virulence, but the wetA deletion mutants produced longer conidia with fewer septa, and the conidia were sensitive to acute stresses, such as oxidative stress and heat stress. Furthermore, the survival rate of aged conidia from the F. graminearum wetA deletion mutants was reduced. The wetA deletion resulted in vigorous generation of single-celled conidia through autophagy-dependent microcycle conidiation, indicating that WetA functions to maintain conidial dormancy by suppressing microcycle conidiation in F. graminearum. Transcriptome analyses demonstrated that most of the putative conidiation-related genes are expressed constitutively and that only a few genes are specifically involved in F. graminearum conidiogenesis. The conserved and distinct roles identified for WetA in F. graminearum provide new insights into the genetics of conidiation in filamentous fungi. PMID:24186953

  17. AbaA Regulates Conidiogenesis in the Ascomycete Fungus Fusarium graminearum

    PubMed Central

    Son, Hokyoung; Kim, Myung-Gu; Min, Kyunghun; Seo, Young-Su; Lim, Jae Yun; Choi, Gyung Ja; Kim, Jin-Cheol; Chae, Suhn-Kee; Lee, Yin-Won

    2013-01-01

    Fusarium graminearum (teleomorph Gibberella zeae) is a prominent pathogen that infects major cereal crops such as wheat, barley, and maize. Both sexual (ascospores) and asexual (conidia) spores are produced in F. graminearum. Since conidia are responsible for secondary infection in disease development, our objective of the present study was to reveal the molecular mechanisms underlying conidiogenesis in F. graminearum based on the framework previously described in Aspergillus nidulans. In this study, we firstly identified and functionally characterized the ortholog of AbaA, which is involved in differentiation from vegetative hyphae to conidia and known to be absent in F. graminearum. Deletion of abaA did not affect vegetative growth, sexual development, or virulence, but conidium production was completely abolished and thin hyphae grew from abnormally shaped phialides in abaA deletion mutants. Overexpression of abaA resulted in pleiotropic defects such as impaired sexual and asexual development, retarded conidium germination, and reduced trichothecene production. AbaA localized to the nuclei of phialides and terminal cells of mature conidia. Successful interspecies complementation using A. nidulans AbaA and the conserved AbaA-WetA pathway demonstrated that the molecular mechanisms responsible for AbaA activity are conserved in F. graminearum as they are in A. nidulans. Results from RNA-sequencing analysis suggest that AbaA plays a pivotal role in conidiation by regulating cell cycle pathways and other conidiation-related genes. Thus, the conserved roles of the AbaA ortholog in both A. nidulans and F. graminearum give new insight into the genetics of conidiation in filamentous fungi. PMID:24039821

  18. Muscodor yucatenensis, a new endophytic ascomycete from Mexican chakah, Bursera simaruba

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During a study on the fungal endophytic associations with some trees of the dry tropical forest of El Eden Ecological Reserve located in the northeast of the Yucatan Peninsula of Mexico, a new fungal species was isolated as an endophyte of a tree named chakah, chachah or huk´up by indigenous mayas. ...

  19. Muscodor yucatanensis, a new endophytic ascomycete from Mexican chakah, Bursera simaruba

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During a study on the fungal endophytic associations with some trees of the secondary forest of El Eden Ecological Reserve located in the northeastern Yucatan Peninsula of Mexico, a new fungal species was isolated as an endophyte of a tree named chakah, chachah or hukúp (Bursera simaruba) by indigen...

  20. New Species and New Records of Buellia (Lichenized Ascomycetes) from Jeju Province, South Korea

    PubMed Central

    Wang, Xin Yu; Liu, Dong; Lőkös, László; Kondratyuk, Sergey Y.; Oh, Soon-Ok; Park, Jung Shin

    2016-01-01

    A new species and 2 new records of lichen genus Buellia were discovered from Chuja-do Island in Jeju Province during a recent floristic survey: B. chujana X. Y. Wang, S. Y. Kondr., L. Lőkös & J.-S. Hur sp. nov., B. halonia (Ach.) Tuck., and B. mamillana (Tuck.) W. A. Weber. The new species is characterized by a brown, areolate thallus, the presence of perlatolic acid, and a saxicolous habitat. Together with previously recorded species, 10 Buellia species were confirmed from Jeju-do Island. Among these species, 3 growing in the exposed rocky area contained xanthone (yellowish lichen thallus, UV + orange), indicating that production of xanthone in this genus might be a defense strategy against the harm of UV light. Although the genus Buellia has been thoroughly studied in Korea before, novel species have been discovered continuously, and large species diversity has been found in this crustose genus, even from a small rocky island. This study indicates that the coastal area harbors a vast number of crustose lichen species, and there is great potential to discover unknown lichens in the coastal rocky area in Korea. PMID:27103850

  1. Dactylospora glaucomarioides (Ascomycetes, Dactylosporaceae): A Lichenicolous Fungus New to South Korea.

    PubMed

    Joshi, Yogesh; Knudsen, Kerry; Wang, Xin Yu; Hur, Jae-Seoun

    2010-12-01

    The lichenicolous fungi flora of South Korea is poorly known. During recent field trips to various parts of South Korea and after an extensive examination of herbarium lichen specimens, we encountered a lichenicolous fungi growing over a thallus of the lichen Ochrolechia yasudae Vain., characterized by small black apothecia with mostly three-septate brown ascospores. It was identified as Dactylospora glaucomarioides. This is the first report of this lichenicolous fungus from South Korea. A taxonomic description and comments are presented. PMID:23956673

  2. A 90-Day Subchronic Toxicity Study of Submerged Mycelial Culture of Cordyceps cicadae (Ascomycetes) in Rats.

    PubMed

    Chen, Yen-Lien; Yeh, Shu-Hsing; Lin, Ting-Wei; Chen, Chin-Chu; Chen, Chin-Shuh; Kuo, Chia-Feng

    2015-01-01

    Cordyceps cicadae is a parasitic fungus that hibernates inside a host (Cicada flammata Dist.) and then grows its fruiting body on the surface of the insect. The complete insect/fungus combination of C. cicadae has been widely applied in Chinese traditional medicine. Recent studies have demonstrated that the medicinal benefits of cultured mycelia are as effective as those found in the wild. However, toxicological information regarding the chronic consumption of C. cicadae mycelia culture is not available. This study was conducted to evaluate the possible toxicity arising from repeated exposure to freeze-dried submerged mycelial culture of C. cicadae for 90 days. A total of eighty 8-week-old Sprague-Dawley rats were divided into 4 groups (10 males and 10 females in each group). C. cicadae was administered daily to animals by gavage at doses of 0, 500, 1000, and 2000 mg/kg body weight for 90 days. No animal deaths occurred and no treatment-related clinical signs were observed during the study period. No statistical differences in body weight gain, relative organ weight, hematology, serum chemistry, and urinalysis were observed. Gross necropsy and histopathological findings indicated that there was no treatment-related abnormality. Based on the results, the no observed adverse effect level of C. cicadae whole broth is determined to be > 2000 mg/kg for male and female Sprague-Dawley rats. The results of this study provides support for the use of C. cicadae fermentation product as a safe agent in functional food. PMID:26559863

  3. New Species and New Records of Buellia (Lichenized Ascomycetes) from Jeju Province, South Korea.

    PubMed

    Wang, Xin Yu; Liu, Dong; Lőkös, László; Kondratyuk, Sergey Y; Oh, Soon-Ok; Park, Jung Shin; Hur, Jae-Seoun

    2016-03-01

    A new species and 2 new records of lichen genus Buellia were discovered from Chuja-do Island in Jeju Province during a recent floristic survey: B. chujana X. Y. Wang, S. Y. Kondr., L. Lőkös & J.-S. Hur sp. nov., B. halonia (Ach.) Tuck., and B. mamillana (Tuck.) W. A. Weber. The new species is characterized by a brown, areolate thallus, the presence of perlatolic acid, and a saxicolous habitat. Together with previously recorded species, 10 Buellia species were confirmed from Jeju-do Island. Among these species, 3 growing in the exposed rocky area contained xanthone (yellowish lichen thallus, UV + orange), indicating that production of xanthone in this genus might be a defense strategy against the harm of UV light. Although the genus Buellia has been thoroughly studied in Korea before, novel species have been discovered continuously, and large species diversity has been found in this crustose genus, even from a small rocky island. This study indicates that the coastal area harbors a vast number of crustose lichen species, and there is great potential to discover unknown lichens in the coastal rocky area in Korea. PMID:27103850

  4. Identification and characterization of polymorphic minisatellites in the phytopathogenic ascomycete Leptosphaeria maculans.

    PubMed

    Eckert, Maria; Gout, Lilian; Rouxel, Thierry; Blaise, Françoise; Jedryczka, Malgorzata; Fitt, Bruce; Balesdent, Marie-Hélène

    2005-01-01

    Leptosphaeria maculans causes phoma stem canker, the most serious disease of oilseed rape world-wide. Sexual recombination is important in the pathogen life cycle and increases the risk of plant resistance genes being overcome rapidly. Thus, there is a need to develop easy-to-use molecular markers suitable for large-scale population genetic studies. The minisatellite MinLm1, showing six alleles in natural populations, has previously been used as a marker to survey populations. Here, we report the characterization of five new minisatellites (MinLm2-MinLm6), of which four were identified by a systematic search for tandemly repeated polymorphic regions in BAC-end sequencing data from L. maculans. Of 782 BAC-end sequences analysed, 43 possessed putative minisatellite-type repeats and four of these (MinLm3-MinLm6) displayed both consistent PCR amplification and size polymorphism in a collection of L. maculans isolates of diverse origins. Cloning and sequencing of each allele confirmed that polymorphism was due to variation in the repeat number of a core motif ranging from 11 bp (MinLm3) to 51 bp (MinLm4). The number of alleles found for each minisatellite ranged from three (MinLm4) to nine (MinLm2), with eight, five and six for MinLm3, MinLm5 and MinLm6, respectively. MinLm2-MinLm6 are all single locus markers specific to L. maculans and share some common features, such as conservation of core motifs and incomplete direct repeats in the flanking regions. To our knowledge, L. maculans is the first fungal species for which six polymorphic single locus minisatellite markers have been reported. PMID:15614492

  5. Intracellular siderophores are essential for ascomycete sexual development in heterothallic Cochliobolus heterostrophus and homothallic Gibberella zeae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Connections between fungal development and secondary metabolism have been reported previously, but as yet, no comprehensive analysis of a family of secondary metabolites and their possible role in fungal development has been reported. In the present study, mutant strains of the heterothallic ascomyc...

  6. Ophiostoma species (Ascomycetes: Ophiostomatales) associated with bark beetles (Coleoptera: Scolytinae) colonizing Pinus radiata in northern Spain.

    PubMed

    Romón, Pedro; Zhou, XuDong; Iturrondobeitia, Juan Carlos; Wingfield, Michael J; Goldarazena, Arturo

    2007-06-01

    Bark beetles (Coleoptera: Scolytinae) are known to be associated with fungi, especially species of Ophiostoma sensu lato and Ceratocystis. However, very little is known about these fungi in Spain. In this study, we examined the fungi associated with 13 bark beetle species and one weevil (Coleoptera: Entiminae) infesting Pinus radiata in the Basque Country of northern Spain. This study included an examination of 1323 bark beetles or their galleries in P. radiata. Isolations yielded a total of 920 cultures, which included 16 species of Ophiostoma sensu lato or their asexual states. These 16 species included 69 associations between fungi and bark beetles and weevils that have not previously been recorded. The most commonly encountered fungal associates of the bark beetles were Ophiostoma ips, Leptographium guttulatum, Ophiostoma stenoceras, and Ophiostoma piceae. In most cases, the niche of colonization had a significant effect on the abundance and composition of colonizing fungi. This confirms that resource overlap between species is reduced by partial spatial segregation. Interaction between niche and time seldom had a significant effect, which suggests that spatial colonization patterns are rarely flexible throughout timber degradation. The differences in common associates among the bark beetle species could be linked to the different niches that these beetles occupy. PMID:17668036

  7. Three New Monotypic Genera of the Caloplacoid Lichens (Teloschistaceae, Lichen-Forming Ascomycetes)

    PubMed Central

    Lőkös, Lászlo; Kim, Jung A.; Kondratiuk, Anna S.; Jeong, Min Hye; Jang, Seol Hwa; Oh, Soon-Ok; Hur, Jae-Seoun

    2015-01-01

    Three monophyletic branches are strongly supported in a phylogenetic analysis of the Teloschistaceae based on combined data sets of internal transcribed spacer and large subunit nrDNA and 12S small subunit mtDNA sequences. These are described as new monotypic genera: Jasonhuria S. Y. Kondr., L. Lőkös et S. -O. Oh, Loekoesia S. Y. Kondr., S. -O. Oh et J. -S. Hur and Olegblumia S. Y. Kondr., L. Lőkös et J. -S. Hur. Three new combinations for the type species of these genera are proposed. PMID:26539034

  8. Evaluation of automated cell disruptor methods for oomycetous and ascomycetous model organisms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two automated cell disruptor-based methods for RNA extraction; disruption of thawed cells submerged in TRIzol Reagent (method QP), and direct disruption of frozen cells on dry ice (method CP), were optimized for a model oomycete, Phytophthora capsici, and compared with grinding in a mortar and pestl...

  9. Origins and Evolution of the HET-s Prion-Forming Protein: Searching for Other Amyloid-Forming Solenoids

    PubMed Central

    Gendoo, Deena M. A.; Harrison, Paul M.

    2011-01-01

    The HET-s prion-forming domain from the filamentous fungus Podospora anserina is gaining considerable interest since it yielded the first well-defined atomic structure of a functional amyloid fibril. This structure has been identified as a left-handed beta solenoid with a triangular hydrophobic core. To delineate the origins of the HET-s prion-forming protein and to discover other amyloid-forming proteins, we searched for all homologs of the HET-s protein in a database of protein domains and fungal genomes, using a combined application of HMM, psi-blast and pGenThreader techniques, and performed a comparative evolutionary analysis of the N-terminal alpha-helical domain and the C-terminal prion-forming domain of HET-s. By assessing the tandem evolution of both domains, we observed that the prion-forming domain is restricted to Sordariomycetes, with a marginal additional sequence homolog in Arthroderma otae as a likely case of horizontal transfer. This suggests innovation and rapid evolution of the solenoid fold in the Sordariomycetes clade. In contrast, the N-terminal domain evolves at a slower rate (in Sordariomycetes) and spans many diverse clades of fungi. We performed a full three-dimensional protein threading analysis on all identified HET-s homologs against the HET-s solenoid fold, and present detailed structural annotations for identified structural homologs to the prion-forming domain. An analysis of the physicochemical characteristics in our set of structural models indicates that the HET-s solenoid shape can be readily adopted in these homologs, but that they are all less optimized for fibril formation than the P. anserina HET-s sequence itself, due chiefly to the presence of fewer asparagine ladders and salt bridges. Our combined structural and evolutionary analysis suggests that the HET-s shape has “limited scope” for amyloidosis across the wider protein universe, compared to the ‘generic’ left-handed beta helix. We discuss the implications of

  10. High natural prevalence of a fungal prion

    PubMed Central

    Debets, Alfons J. M.; Dalstra, Henk J. P.; Slakhorst, Marijke; Koopmanschap, Bertha; Hoekstra, Rolf F.; Saupe, Sven J.

    2012-01-01

    Prions are infectious proteins that cause fatal diseases in mammals. Prions have also been found in fungi, but studies on their role in nature are scarce. The proposed biological function of fungal prions is debated and varies from detrimental to benign or even beneficial. [Het-s] is a prion of the fungus Podospora anserina. The het-s locus exists as two antagonistic alleles that constitute an allorecognition system: the het-s allele encoding the protein variant capable of prion formation and the het-S allele encoding a protein variant that cannot form a prion. We document here that het-s alleles, capable of prion formation, are nearly twice as frequent as het-S alleles in a natural population of 112 individuals. Then, we report a 92% prevalence of [Het-s] prion infection among the het-s isolates and find evidence of the role of the [Het-s]/het-S allorecognition system on the incidence of infection by a deleterious senescence plasmid. We explain the het-s/het-S allele ratios by the existence of two selective forces operating at different levels. We propose that during the somatic stage, the role of [Het-s]/HET-S in allorecognition leads to frequency-dependent selection for which an equilibrated frequency would be optimal. However, in the sexual cycle, the [Het-s] prion causes meiotic drive favoring the het-s allele. Our findings indicate that [Het-s] is a selected and, therefore, widespread prion whose activity as selfish genetic element is counteracted by balancing selection for allorecognition polymorphism. PMID:22691498

  11. Analyzing the birth and propagation of two distinct prions, [PSI+] and [Het-s](y), in yeast.

    PubMed

    Mathur, Vidhu; Taneja, Vibha; Sun, Yidi; Liebman, Susan W

    2010-05-01

    Various proteins, like the infectious yeast prions and the noninfectious human Huntingtin protein (with expanded polyQ), depend on a Gln or Asn (QN)-rich region for amyloid formation. Other prions, e.g., mammalian PrP and the [Het-s] prion of Podospora anserina, although still able to form infectious amyloid aggregates, do not have QN-rich regions. Furthermore, [Het-s] and yeast prions appear to differ dramatically in their amyloid conformation. Despite these differences, a fusion of the Het-s prion domain to GFP (Het-sPrD-GFP) can propagate in yeast as a prion called [Het-s](y). We analyzed the properties of two divergent prions in yeast: [Het-s](y) and the native yeast prion [PSI(+)] (prion form of translational termination factor Sup35). Curiously, the induced appearance and transmission of [PSI(+)] and [Het-s](y) aggregates is remarkably similar. Overexpression of tagged prion protein (Sup35-GFP or Het-sPrD-GFP) in nonprion cells gives rise to peripheral, and later internal, ring/mesh-like aggregates. The cells with these ring-like aggregates give rise to daughters with one (perivacuolar) or two (perivacuolar and juxtanuclear) dot-like aggregates per cell. These line, ring, mesh, and dot aggregates are not really the transmissible prion species and should only be regarded as phenotypic markers of the presence of the prions. Both [PSI(+)] and [Het-s](y) first appear in daughters as numerous tiny dot-like aggregates, and both require the endocytic protein, Sla2, for ring formation, but not propagation. PMID:20219972

  12. Comparison of fungal carbohydrate esterases of family CE16 on artificial and natural substrates.

    PubMed

    Puchart, Vladimír; Agger, Jane W; Berrin, Jean-Guy; Várnai, Anikó; Westereng, Bjørge; Biely, Peter

    2016-09-10

    The enzymatic conversion of acetylated hardwood glucuronoxylan to functional food oligomers, biochemicals or fermentable monomers requires besides glycoside hydrolases enzymes liberating acetic acid esterifying position 2 and/or 3 in xylopyranosyl (Xylp) residues. The 3-O-acetyl group at internal Xylp residues substituted by MeGlcA is the only acetyl group of hardwood acetylglucuronoxylan and its fragments not attacked by acetylxylan esterases of carbohydrate esterase (CE) families 1, 4, 5 and 6 and by hemicellulolytic acetyl esterases classified in CE family 16. Monoacetylated aldotetraouronic acid 3″-Ac(3)MeGlcA(3)Xyl3, generated from the polysaccharide by GH10 endoxylanases, appears to be one of the most resistant fragments. The presence of the two substituents on the non-reducing-end Xylp residue prevents liberation of MeGlcA by α-glucuronidase of family GH67 and blocks the action of acetylxylan esterases. The Ac(3)MeGlcA(3)Xyl3 was isolated from an enzymatic hydrolysate of birchwood acetylglucuronoxylan and characterized by (1)H NMR spectroscopy as a mixture of two positional isomers, 3″-Ac(3)MeGlcA(3)Xyl3 and 4″-Ac(3)MeGlcA(3)Xyl3, the latter being the result of acetyl group migration. The mixture was used as a substrate for three members of CE16 family of fungal origin. Trichoderma reesei CE16 esterase, inactive on polymeric substrate, deacetylated both isomers. Podospora anserina and Aspergillus niger esterases, active on acetylglucuronoxylan, deesterified effectively only the 4″-isomer. The results indicate catalytic diversity among CE16 enzymes, but also their common and unifying catalytic ability to exo-deacetylate positions 3 and 4 on non-reducing-end Xylp residues, which is an important step in plant hemicellulose saccharification. PMID:27439201

  13. The Homologue of het-c of Neurospora crassa Lacks Vegetative Compatibility Function in Fusarium proliferatum†

    PubMed Central

    Kerényi, Zoltán; Oláh, Brigitta; Jeney, Apor; Hornok, László; Leslie, John F.

    2006-01-01

    For two fungal strains to be vegetatively compatible and capable of forming a stable vegetative heterokaryon they must carry matching alleles at a series of loci variously termed het or vic genes. Cloned het/vic genes from Neurospora crassa and Podospora anserina have no obvious functional similarity and have various cellular functions. Our objective was to identify the homologue of the Neurospora het-c gene in Fusarium proliferatum and to determine if this gene has a vegetative compatibility function in this economically important and widely dispersed fungal pathogen. In F. proliferatum and five other closely related Fusarium species we found a few differences in the DNA sequence, but the changes were silent and did not alter the amino acid sequence of the resulting protein. Deleting the gene altered sexual fertility as the female parent, but it did not alter male fertility or existing vegetative compatibility interactions. Replacement of the allele-specific portion of the coding sequence with the sequence of an alternate allele in N. crassa did not result in a vegetative incompatibility response in transformed strains of F. proliferatum. Thus, the fphch gene in Fusarium appears unlikely to have the vegetative compatibility function associated with its homologue in N. crassa. These results suggest that the vegetative compatibility phenotype may result from convergent evolution. Thus, the genes involved in this process may need to be identified at the species level or at the level of a group of species and could prove to be attractive targets for the development of antifungal agents. PMID:17021201

  14. Recombination and Replication of Plasmid-like Derivatives of a Short Section of the Mitochondrial Chromosome of Neurospora Crassa

    PubMed Central

    Gross, S. R.; Levine, P. H.; Metzger, S.; Glaser, G.

    1989-01-01

    The 21-kbp mitochondrial chromosome of the stp-ruv strain of Neurospora crassa undergoes regional amplification yielding plasmid-like supercoiled circles varying in size from subunit length to very high multimers. A comparison of the base sequence of the five plasmids studied, with the region of the chromosome from which they were derived, indicated that the amplified chromosomal segments were determined by a recombination-excision process near or within two structurally distinctive regions. One of these, consisting of nearly uninterrupted strings of Cs and Gs straddling tandem PstI site direct repeats, could form an extended hairpin loop with only a few mismatches. It was found at or near the 5' exchange point of all of the plasmids. An extended 35-bp sequence containing 17-bp direct repeats was the primary 3' site of exchange. Base sequence changes were found in the vicinity of exchange points. Most notable of these was a G insertion and T to C transition within a section of the 5' region likely to form a hairpin loop, suggesting the involvement of a mismatch repair-like mechanism in the recombination process. The sequence, TATATAGACATATA, was identified as a likely candidate for the site of replication initiation. A nearly identical sequence was found common to all of the corresponding plasmids of Podospora anserina and was reported near the presumed replication origin of the Drosophila yakuba mitochondrial chromosome. A search of GenBank revealed a remarkable association of the consensus sequence, TATATAGAXATATA, with the plus strand of organelle DNA. PMID:2524421

  15. Signal Transduction by a Fungal NOD-Like Receptor Based on Propagation of a Prion Amyloid Fold

    PubMed Central

    Daskalov, Asen; Habenstein, Birgit; Martinez, Denis; Debets, Alfons J. M.; Sabaté, Raimon; Loquet, Antoine; Saupe, Sven J.

    2015-01-01

    In the fungus Podospora anserina, the [Het-s] prion induces programmed cell death by activating the HET-S pore-forming protein. The HET-s β-solenoid prion fold serves as a template for converting the HET-S prion-forming domain into the same fold. This conversion, in turn, activates the HET-S pore-forming domain. The gene immediately adjacent to het-S encodes NWD2, a Nod-like receptor (NLR) with an N-terminal motif similar to the elementary repeat unit of the β-solenoid fold. NLRs are immune receptors controlling cell death and host defense processes in animals, plants and fungi. We have proposed that, analogously to [Het-s], NWD2 can activate the HET-S pore-forming protein by converting its prion-forming region into the β-solenoid fold. Here, we analyze the ability of NWD2 to induce formation of the β-solenoid prion fold. We show that artificial NWD2 variants induce formation of the [Het-s] prion, specifically in presence of their cognate ligands. The N-terminal motif is responsible for this prion induction, and mutations predicted to affect the β-solenoid fold abolish templating activity. In vitro, the N-terminal motif assembles into infectious prion amyloids that display a structure resembling the β-solenoid fold. In vivo, the assembled form of the NWD2 N-terminal region activates the HET-S pore-forming protein. This study documenting the role of the β-solenoid fold in fungal NLR function further highlights the general importance of amyloid and prion-like signaling in immunity-related cell fate pathways. PMID:25671553

  16. The mitochondrial genome of the ethanol-metabolizing, wine cellar mold Zasmidium cellare is the smallest for a filamentous ascomycete.

    PubMed

    Goodwin, Stephen B; McCorison, Cassandra B; Cavaletto, Jessica R; Culley, David E; LaButti, Kurt; Baker, Scott E; Grigoriev, Igor V

    2016-08-01

    Fungi in the class Dothideomycetes often live in extreme environments or have unusual physiology. One of these, the wine cellar mold Zasmidium cellare, produces thick curtains of mycelia in cellars with high humidity, and its ability to metabolize volatile organic compounds is thought to improve air quality. Whether these abilities have affected its mitochondrial genome is not known. To fill this gap, the circular-mapping mitochondrial genome of Z. cellare was sequenced and, at only 23 743 bp, is the smallest reported for a filamentous fungus. Genes were encoded on both strands with a single change of direction, different from most other fungi but consistent with the Dothideomycetes. Other than its small size, the only unusual feature of the Z. cellare mitochondrial genome was two copies of a 110-bp sequence that were duplicated, inverted and separated by approximately 1 kb. This inverted-repeat sequence confused the assembly program but appears to have no functional significance. The small size of the Z. cellare mitochondrial genome was due to slightly smaller genes, lack of introns and non-essential genes, reduced intergenic spacers and very few ORFs relative to other fungi rather than a loss of essential genes. Whether this reduction facilitates its unusual biology remains unknown. PMID:27521628

  17. Kazachstania yasuniensis sp. nov., an ascomycetous yeast species found in mainland Ecuador and on the Galápagos.

    PubMed

    James, Stephen A; Carvajal Barriga, Enrique Javier; Portero Barahona, Patricia; Nueno-Palop, Carmen; Cross, Kathryn; Bond, Christopher J; Roberts, Ian N

    2015-04-01

    Seven strains representing a novel yeast species belonging to the genus Kazachstania were found at several collection sites on both mainland Ecuador (Yasuní National Park) and the Galápagos (Santa Cruz Island). Two strains (CLQCA 20-132(T) and CLQCA 24SC-045) were isolated from rotten wood samples, two further strains (CLQCA 20-280 and CLQCA 20-348) were isolated from soil samples, and three strains (CLQCA 20-198, CLQCA 20-374 and CLQCA 20-431) were isolated from decaying fruits. Sequence analyses of the D1/D2 domains of the LSU rRNA gene and ribosomal internal transcribed spacer (ITS) region indicated that the novel species is most closely related to Kazachstania servazzii and Kazachstania unispora. Although the strains could not be distinguished from one another based upon their differing geographical origins, they could be differentiated according to their isolation source (fruit, soil or wood) by ITS sequencing. The species name Kazachstania yasuniensis sp. nov. is proposed to accommodate these strains, with CLQCA 20-132(T) ( = CBS 13946(T) = NCYC 4008(T)) designated the type strain. PMID:25644482

  18. Host colonization and substrate utilization by wood-colonizing Ascomycete fungi in the grapevine trunk disease complex

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Grapevine trunk diseases cause chronic wood infections (cankers) in mixed infections within the same vine. To determine the synergistic interactions of trunk-pathogen communities and their impact on the host we are characterizing, on a pathogen-by-pathogen basis, fungal damage to woody cells and tis...

  19. [Selection of isolates of entomopathogenic fungus Beauveria bassiana (Ascomycetes: Clavicipitaceae) for control of Rhipicephalus (Boophilus) microplus (Acari: Ixodidae)].

    PubMed

    Barci, Leila A G; de Almeida, José Eduardo M; de Campos Nogueira, Adriana H; Zappelini, Luciano O; do Prado, Angelo P

    2009-12-01

    This study was carried out to select isolates of the entomopathogenic fungus Beauveria bassiana with pathogenic potential to control the Rhipicephalus (Boophilus) microplus tick. The effectiveness of thirty isolates was first tested at a concentration of 5 x 108 conidia.mL(-1). Of these, eight were evaluated (IBCB01, IBCB02, IBCB07, IBCB17, IBCB21, IBCB74, IBCB149, IBCB165) and showed an effectiveness between 90 and 99%; thirteen (IBCB03, IBCB14, IBCB16, IBCB24, IBCB95, IBCB97, IBCB102, IBCB141, IBCB146, IBCB147, IBCB150, IBCB154, IBCB157) between 80 and 89,5%; six (IBCB47, IBCB75, IBCB84, IBCB145, IBCB161, IBCB164) between 70 and 79%, and only two (IBCB13 and IBCB143) had lower pathogenicity (70% or below). In the second step of the study, the five more effective strains in the first phase of the experiment (IBCB01, IBCB07, IBCB21, IBCB66, IBCB165) were analyzed comparatively. Based on in vitro results, it can be concluded that IBCB66 and IBCB21 are the isolates with higher potential for field control of R. (B.) microplus. IBCB01, IBCB07, IBCB21, IBCB66 e IBCB165 isolates were submitted to a conidial production test using a rice-based substrate. The best mass production of the entomopathogenic fungus was obtained with the IBCB66 strain. PMID:20040184

  20. Taxonomy and phylogeny of the ascomycetous yeast genus Zygoascus, with proposal of Zygoascus meyerae sp. nov. and related anamorphic varieties.

    PubMed

    Smith, Maudy Th; Robert, V; Poot, G A; Epping, Wendy; de Cock, A W A M

    2005-05-01

    Physiological characters, mating compatibility, PCR-RAPD fingerprints, mol% G + C content, DNA-DNA relatedness, and large-subunit and internal transcribed spacer rRNA gene sequences of strains assigned to the genus Zygoascus were re-examined. On the basis of those data, and after phylogenetic analyses, an emendation of Zygoascus hellenicus (type material is a cross of CBS 6736(T) x CBS 5839(T)) is proposed, comprising two novel anamorphic varieties, Candida steatolytica var. steatolytica (CBS 6736(T)) and C. steatolytica var. inositophila (CBS 5839(T)). A novel teleomorphic species, Zygoascus meyerae sp. nov. (type material is a cross of CBS 4099(T) x CBS 7521(T)) is described, together with two novel anamorphic varieties corresponding to it, Candida hellenica var. hellenica (CBS 4099(T)) and C. hellenica var. acidophila (CBS 7115(T)). PMID:15879282

  1. GzSNF1 is required for normal sexual and asexual development in the ascomycete Gibberella zeae.

    PubMed

    Lee, Seung-Ho; Lee, Jungkwan; Lee, Seunghoon; Park, Eun-Hee; Kim, Ki-Woo; Kim, Myoung-Dong; Yun, Sung-Hwan; Lee, Yin-Won

    2009-01-01

    The sucrose nonfermenting 1 (SNF1) protein kinase of yeast plays a central role in the transcription of glucose-repressible genes in response to glucose starvation. In this study, we deleted an ortholog of SNF1 from Gibberella zeae to characterize its functions by using a gene replacement strategy. The mycelial growth of deletion mutants (DeltaGzSNF1) was reduced by 21 to 74% on diverse carbon sources. The virulence of DeltaGzSNF1 mutants on barley decreased, and the expression of genes encoding cell-wall-degrading enzymes was reduced. The most distinct phenotypic changes were in sexual and asexual development. DeltaGzSNF1 mutants produced 30% fewer perithecia, which matured more slowly, and asci that contained one to eight abnormally shaped ascospores. Mutants in which only the GzSNF1 catalytic domain was deleted had the same phenotype changes as the DeltaGzSNF1 strains, but the phenotype was less extreme in the mutants with the regulatory domain deleted. In outcrosses between the DeltaGzSNF1 mutants, each perithecium contained approximately 70% of the abnormal ascospores, and approximately 50% of the asci showed unexpected segregation patterns in a single locus tested. The asexual spores of the DeltaGzSNF1 mutants were shorter and had fewer septa than those of the wild-type strain. The germination and nucleation of both ascospores and conidia were delayed in DeltaGzSNF1 mutants in comparison with those of the wild-type strain. GzSNF1 expression and localization depended on the developmental stage of the fungus. These results suggest that GzSNF1 is critical for normal sexual and asexual development in addition to virulence and the utilization of alternative carbon sources. PMID:19028993

  2. FgFlbD regulates hyphal differentiation required for sexual and asexual reproduction in the ascomycete fungus Fusarium graminearum.

    PubMed

    Son, Hokyoung; Kim, Myung-Gu; Chae, Suhn-Kee; Lee, Yin-Won

    2014-11-01

    Fusarium graminearum is a filamentous fungal plant pathogen that infects major cereal crops. The fungus produces both sexual and asexual spores in order to endure unfavorable environmental conditions and increase their numbers and distribution across plants. In a model filamentous fungus, Aspergillus nidulans, early induction of conidiogenesis is orchestrated by the fluffy genes. The objectives of this study were to characterize fluffy gene homologs involved in conidiogenesis and their mechanism of action in F. graminearum. We characterized five fluffy gene homologs in F. graminearum and found that FlbD is the only conserved regulator for conidiogenesis in A. nidulans and F. graminearum. Deletion of fgflbD prevented hyphal differentiation and the formation of perithecia. Successful interspecies complementation using A. nidulans flbD demonstrated that the molecular mechanisms responsible for FlbD functions are conserved in F. graminearum. Moreover, abaA-wetA pathway is positively regulated by FgFlbD during conidiogenesis in F. graminearum. Deleting fgflbD abolished morphological effects of abaA overexpression, which suggests that additional factors for FgFlbD or an AbaA-independent pathway for conidiogenesis are required for F. graminearum conidiation. Importantly, this study led to the construction of a genetic pathway of F. graminearum conidiogenesis and provides new insights into the genetics of conidiogenesis in fungi. PMID:25277408

  3. Candida heliconiae sp. nov., Candida picinguabensis sp. nov. and Candida saopaulonensis sp. nov., three ascomycetous yeasts from Heliconia velloziana (Heliconiaceae).

    PubMed

    Ruivo, Carla C C; Lachance, Marc-André; Rosa, Carlos A; Bacci, Maurício; Pagnocca, Fernando C

    2006-05-01

    Strains belonging to three novel yeast species, Candida heliconiae (four isolates), Candida picinguabensis (three isolates) and Candida saopaulonensis (two isolates), were recovered in the year 2000 from water of flower bracts of Heliconia velloziana L. Emigd. (Heliconiaceae) found in a forest ecosystem site in an Atlantic rainforest of south-eastern Brazil. C. picinguabensis and C. saopaulonensis were nearly identical in morphology and physiology, but sequence divergence in the D1/D2 domain of the large-subunit rDNA indicated that they should be regarded as different species. They belong to the Metschnikowiaceae clade. C. heliconiae had affinities to Pichia mexicana and related species, but was genetically isolated from all currently accepted species in that group. The type strains are C. heliconiae UNESP 00-91C1T (=CBS 10000T=NRRL Y-27813T), C. picinguabensis UNESP 00-89T (=CBS 9999T=NRRL Y-27814T) and C. saopaulonensis UNESP 00-99T (=CBS 10001T=NRRL Y-27815T). PMID:16627669

  4. Wickerhamiella pagnoccae sp. nov. and Candida tocantinsensis sp. nov., two ascomycetous yeasts from flower bracts of Heliconia psittacorum (Heliconiaceae).

    PubMed

    Barbosa, Anne C; Morais, Camila G; Morais, Paula B; Rosa, Luiz H; Pimenta, Raphael S; Lachance, Marc-André; Rosa, Carlos A

    2012-02-01

    Two novel yeast species were isolated from nectar of flower bracts of Heliconia psittacorum (Heliconiaceae) collected in a Cerrado ecosystem in the state of Tocantins, northern Brazil. Wickerhamiella pagnoccae sp. nov., which is closely related to Candida jalapaonensis, is heterothallic and produces one spheroid ascospore per ascus. Candida tocantinsensis sp. nov. belongs to the Metschnikowiaceae clade and its nearest relative is Candida ubatubensis, but the sequence identity (%) in the D1/D2 domains of the rRNA gene is low. The type strain of W. pagnoccae is UFMG-F18C1(T) ( = CBS 12178(T) = NRRL Y-48735(T)) and the type strain of C. tocantinsensis is UFMG-F16D1(T) ( = CBS 12177(T) = NRRL Y-48734(T)). PMID:21478396

  5. Various grain substrates for the production of fruiting bodies and bioactive compounds of the medicinal caterpillar mushroom, Cordyceps militaris (Ascomycetes).

    PubMed

    Liang, Zeng-Chin; Liang, Chih-Hung; Wu, Chiu-Yeh

    2014-01-01

    In this study, several grains such as brown rice (Br), plumule rice (Pr), wheat (W) and pearl barley (Pb) supplemented with 1% (w/w) peptone (P), yeast extract (Ye), ammonia sulfate (As), and monosodium glutamate (Mg) as a nitrogen source, respectively, were used to produce fruiting bodies and bioactive compounds of two strains of Cordyceps militaris. Among these grain substrates, the substrate most suitable to mycelial growth was Pb+Ye for C. militaris H and L. The mushroom strains colonized this substrate in 12.8 and 12.6 days, respectively. For C. militaris L, the fewest days were required for primordial initiation on Br+Ye and Pr+P substrates. The highest yield and biological efficiency was observed with Pb substrate (25.16 g/bottle and 87.36%) and Br+P substrate (21.84 g/bottle and 75.83%) for C. militaris H and L, respectively. In the fruiting bodies of C. militaris H, the highest cordycepin content was cultivated on W+Mg substrate (25.07 mg/g), the highest mannitol content was cultivated with Pr+Mg (153.21 mg/g) and Pr (151.65 mg/g) substrates, and the highest adenosine content was cultivated with Pr+Ye (0.94 mg/g) and Pb+Ye (0.90 mg/g) substrates. In the fruiting bodies of C. militaris L, the highest cordycepin content was cultivated with W+Mg substrate (22.14 mg/g); the highest mannitol content was cultivated with Pb substrate (189.33 mg/g); and the highest adenosine content was cultivated with Pb+Ye substrate (0.71 mg/g). PMID:25404221

  6. Cultivation of medicinal caterpillar fungus, Cordyceps militaris (Ascomycetes), and production of cordycepin using the spent medium from levan fermentation.

    PubMed

    Wu, Fang-Chen; Chen, Yi-Lin; Chang, Shu-Ming; Shih, Ing-Lung

    2013-01-01

    A process of tandem cultivation for the production of green and invaluable bioproducts (levan and Cordycepes militaris) useful for medical applications has been successfully developed. The process involves first cultivating Bacillus subtilis strain natto in sucrose medium to produce levan, followed by the subsequent cultivation of C. militaris in liquid- and solid-state cultures using the spent medium from levan fermentation as substrates. The factors affecting the cell growth and production of metabolites of C. militaris were investigated, and the various metabolites produced in the culture filtrate, mycelia, and fruiting body were analyzed. In addition, cordycepin was prepared from the solid waste medium of C. militaris. This is an excellent example in the development of cost effective biorefineries that maximize useful product formation from the available biomass. The preparation of cordycepin from solid waste medium of C. militaris using a method with high extraction efficiency and minimum solvent usage is also environmentally friendly. PMID:23796221

  7. Cytological Characterization of Anamorphic Fungus Lecanicillium pui and Its Relationship with Chinese Caterpillar Mushroom, Ophiocordyceps sinensis (Ascomycetes).

    PubMed

    Lei, Wei; Zhang, Guren; Wu, Guangguo; Liu, Xin

    2016-01-01

    Ophiocordyceps sinensis (syn. Cordyceps sinensis), one of the most valuable medicinal mushrooms, has great economic importance on the Tibetan Plateau. We isolated an anamorphic fungus Lecanicillium pui from natural O. sinensis specimens and found that the optimal temperature for its culture on potato dextrose agar media was 25°C. Cell ultrastructure in L. pui hyphae and spores was characterized by transmission electron microscopy, and it was observed that some primary organelles showed the typical fungal features. Five chemical elements were determined in this fungus and niobium was discovered for the first time even with trace amounts. A species-specific method, nested polymerase chain reaction, was established to investigate the colonization of this fungus. Thus, the extensive distribution of L. pui on O. sinensis, in the shape of hyphae or mycelia, suggested that it may have subtle and chronic effects on the growth of the O. sinensis teleomorphic stage. These findings provide a potential reference, in the view of microbial ecology, for the study on the occurrence and mechanism of development of O. sinensis. PMID:27279447

  8. Review on Natural Enemies and Diseases in the Artificial Cultivation of Chinese Caterpillar Mushroom, Ophiocordyceps sinensis (Ascomycetes).

    PubMed

    Lu, Zenghui; Shi, Ping; He, Yuanchuan; Zhang, Deli; He, Zongyi; Chen, Shijiang; Tu, Yongqin; Li, Li; Liu, Fei; Zeng, Wei

    2015-01-01

    Ophiocordyceps sinensis (syn. Cordyceps sinensis), well known as DongChongXiaCao (DCXC), is one of the most valuable traditional Chinese medicinal species. In this article, we provide a systematic review of natural enemies and diseases encountered in artificial cultivation of DCXC. Unfortunately, DCXC has been endangered over the past decades due to overharvesting and a worsening ecological environment. Therefore, the artificial cultivation of DCXC has been extensively investigated in recent years. Complete indoor artificial cultivation and semi-field cultivation are the two most common strategies used to cultivate DCXC. However, cultured DCXCs are often attacked by various natural enemies and diseases, which have resulted in substantial loss of the valuable medicinal resource. In this study, we have summarized the species of natural enemies and types of diseases confronted by DCXC. Twenty reported natural enemy species are categorized into four classes, one of which is reported for the first time in this study. Moreover, six microbial pathogens are also discussed. The recapitulation of the natural enemies and diseases in DCXC artificial cultivation not only promote the development of integrated pest management of DCXC cultivation but also provide important information to help preserve and develop this valuable resource. PMID:26559703

  9. Cordyceps s.l. (Ascomycetes) Species Used as Medicinal Mushrooms are Closely Related with Higher Ability to Produce Cordycepin.

    PubMed

    Kuo, Hsiao-Che; Huang, I-Ching; Chen, Tzong-Yueh

    2015-01-01

    Cordyceps s.l. (sensu lato) species have been used as herbal medicines; one of their main constituents is cordycepin. As genome sequencing techniques have become more cost-effective and more popular, more entomogenous fungal genomes have been sequenced and published. Here, we constructed a phylogenetic tree based on 18S rRNA sequences from Cordyceps species and analyzed the copy number of the key enzymes involved in biosynthesis of cordycepin from related fungal genomes that have been published. The sequences of the 18S rRNA gene were examined, and seven single nucleotides were found that could represent the evolutionary history of Cordyceps s.l. and which perfectly fit the phylogenetic tree. Their evolution was influenced mainly by host factors, rather than geographical location. The Cordyceps s.l. species that are used as herbal medicines are closely related in the phylogenetic tree. The major species for Chinese pharmaceutical markets, such as C. militaris and C. sinensis, have higher copy numbers of 5'-nucleotidase and adenylate kinase, and ribonucleotide reductases (RNRs), respectively. Moreover, absence of an RNR inhibitor may cause cordycepin accumulation. Presence of an RNR inhibitor may lead to lower cordycepin levels in fungal species in which no medicinal applications have been described. Cordycepin is not only an important secondary metabolite that is used as an herbal medicine, but it also has significance for understanding the evolution of these entomogenous species. PMID:26853963

  10. Protective Efficacy of the Caterpillar Mushroom, Ophiocordyceps sinensis (Ascomycetes), from India in Neuronal Hippocampal Cells against Hypoxia.

    PubMed

    Pal, Mamta; Bhardwaj, Anuja; Manickam, Manimaran; Tulsawani, Rajkumar; Srivastava, Mousami; Sugadev, Ragumani; Misra, Kshipra

    2015-01-01

    This study demonstrated the protective efficiency of extracts of the Indian variety of Ophiocordyceps sinensis (=Cordyceps sinensis) (CSEs) in HT22 (murine hippocampal) cells under hypoxic conditions. Various parameters such as cell viability, reactive oxygen species, levels of endogenous antioxidants, inflammatory cytokines, transcription factors, and oxidation of macromolecules were analyzed. In addition, the radical scavenging abilities of hydroxyl radicals, nitric oxide, and superoxide radicals were also studied. Antioxidant compounds, ascorbic acid, hesperidin, and rutin were quantified by high-performance thin-layer chromatography. The information acquired from high-performance thin-layer chromatography profiling was subjected to principal component analysis for data clustering. Findings of this research revealed that ascorbic acid and rutin were highest in aqueous CSE, whereas the maximum amount of hesperidin was found in 25% alcoholic CSE. In vitro studies showed that all the CSEs protected HT22 cells well by upregulating the level of endogenous antioxidants and preventing the oxidation of lipids and proteins. These extracts also reduced the amount of hypoxia-induced inflammatory cytokines and transcription factors on par with the normoxic control with more or less equal protection in the cells under hypoxia, and indicated significant radical scavenging potential. PMID:26756295

  11. [Insecticidal and immunosuppressive effect of ascomycete Cordyceps militaris on the larvae of the Colorado potato beetle Leptinotarsa decemlineata].

    PubMed

    Kriukov, V Iu; Iaroslavtseva, O N; Dubovskiĭ, I M; Tiurin, M V; Kriukova, N A; Glupov, V V

    2014-01-01

    The immunosuppressive and insecticidal activity of cultures of the entomopathogenic fungus Cordyceps militaris on the larvae of the Colorado potato beetle Leptinotarsa decemlineata has been established for the first time. It was found that the peroral effect of the fungal culture resulted in dose-dependent decrease in survival, delayed in development time and molting, decreases in the total hemocyt counts, increased activity of phenoloxidases in the hemolymph, and reduced activity of the enzyme in the cuticle, as well as increased sensitivity of larvae to the fungus Beauveria bassiana at the level of the synergistic effect. PMID:25731041

  12. A transcriptomic study of grapevine (Vitis vinifera cv. Cabernet-Sauvignon) interaction with the vascular ascomycete fungus Eutypa lata

    PubMed Central

    Camps, Céline; Kappel, Christian; Lecomte, Pascal; Léon, Céline; Gomès, Eric; Coutos-Thévenot, Pierre; Delrot, Serge

    2010-01-01

    Eutypa dieback is a vascular disease that may severely affect vineyards throughout the world. In the present work, microarrays were made in order (i) to improve our knowledge of grapevine (Vitis vinifera cv. Cabernet-Sauvignon) responses to Eutypa lata, the causal agent of Eutypa dieback; and (ii) to identify genes that may prevent symptom development. Qiagen/Operon grapevine microarrays comprising 14 500 probes were used to compare, under three experimental conditions (in vitro, in the greenhouse, and in the vineyard), foliar material of infected symptomatic plants (S+R+), infected asymptomatic plants (S–R+), and healthy plants (S–R–). These plants were characterized by symptom notation after natural (vineyard) or experimental (in vitro and greenhouse) infection, re-isolation of the fungus located in the lignified parts, and the formal identification of E. lata mycelium by PCR. Semi-quantitative real-time PCR experiments were run to confirm the expression of some genes of interest in response to E. lata. Their expression profiles were also studied in response to other grapevine pathogens (Erysiphe necator, Plasmopara viticola, and Botrytis cinerea). (i) Five functional categories of genes, that is those involved in metabolism, defence reactions, interaction with the environment, transport, and transcription, were up-regulated in S+R+ plants compared with S–R– plants. These genes, which cannot prevent infection and symptom development, are not specific since they were also up-regulated after infection by powdery mildew, downy mildew, and black rot. (ii) Most of the genes that may prevent symptom development are associated with the light phase of photosynthesis. This finding is discussed in the context of previous data on the mode of action of eutypin and the polypeptide fraction secreted by Eutypa. PMID:20190040

  13. Efficacy of entomopathogenic fungi (Ascomycetes: Hypocreales) against adult Haematobia irritans (Diptera: Muscidae) under stable conditions in the Mexican dry tropics.

    PubMed

    Galindo-Velasco, E; Lezama-Gutiérrez, R; Cruz-Vázquez, C; Pescador-Rubio, A; Angel-Sahagún, C A; Ojeda-Chi, M M; Rodríguez-Vivas, R I; Contreras-Lara, D

    2015-04-30

    The purpose of this paper is to evaluate the effect of five strains of Metarhizium anisopliae (Ma) and three strains of Isaria fumosorosea (Ifr) at a concentration of 1×10(8)colony-forming units/ml applied by spraying onto bovines with controlled infestation of Haematobia irritans under stable conditions in the Mexican dry tropics. Four experiments were performed, in each of which three treatments (two fungal strains and one control) were evaluated with eight repetitions for each one, by carrying out a single application of the aqueous suspension of each strain. The animals were isolated in individual cages and direct counts of the infestation were carried out for 13 days. It was observed that strains Ma2, Ma6, Ma10, Ma14, and Ma34 caused 94-100% reduction in infestation between days 12 and 13 post-treatment, while strains Ifr19, Ifr11, and Ifr12 reduced infestation from 90% to 98% up to day 13 post-application. There was an effect in the generation of horn flies from the excrement of bovines that were treated with different strains, reducing the reproduction of subsequent generations. It was concluded that the strains of M. anisopliae and I. fumosorosea evaluated in this study can be used as biocontrol agents in infestations of H. irritans in stabled bovines. PMID:25771932

  14. On the reclassification of species assigned to Candida and other anamorphic ascomycetous yeast genera based on phylogenetic circumscription

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Multigene phylogenies have been instrumental in revising the classification of ascosporic (teleomorph) yeasts in a natural system based on lines of decent. Although many taxonomic changes have already been implemented for teleomorph taxa, this is not yet the case for the large genus Candida and smal...

  15. Immune-Modulating Activity of Extract Prepared from Mycelial Culture of Chinese Caterpillar Mushroom, Ophiocordyceps sinensis (Ascomycetes).

    PubMed

    Jang, Sun-Hee; Kim, Sae-Hae; Lee, Ha-Yan; Jang, Seung-Hwan; Jang, Hyonseok; Chae, Soo-Wan; Jung, Su-Jin; So, Byung-Ok; Ha, Ki-Chan; Sin, Hong-Sig; Jang, Yong-Suk

    2015-01-01

    Ophiocordyceps sinensis is a natural fungus that has been valued as a health food and traditional Chinese medicine for centuries. The fungus is parasitic and colonizes insect larva. Naturally occurring O. sinensis thrives at high altitude in cold and grassy alpine meadows on the Himalayan mountain ranges. Wild O. sinensis is becoming increasingly rare in its natural habitats, and its price is out of reach for clinical practice. For these reasons, development of a standardized alternative is a great focus of research to allow the use of O. sinensis as a medicine. To develop an alternative for wild O. sinensis, a refined standardized extract, CBG-CS-2, was produced by artificial fermentation and extraction of the mycelial strain Paecilomyces hepiali CBG-CS-1, which originated from wild O. sinensis. In this study, we analyzed the in vivo immune-modulating effect of CBG-CS-2 in mice. Oral administration of CBG-CS-2 supported splenocyte stimulation and enhanced Th1-type cytokine expression from the splenocytes. Importantly, the same treatment significantly enhanced the natural killer cell activity of the splenocytes. Finally, oral administration of CBG-CS-2 enhanced the potential for inflammatory responses. Together, these findings indicate that the mycelial culture extract prepared from O. sinensis exhibited immune-modulating activity and suggest its possible use in the treatment of diseases caused by abnormal immune function. PMID:26854106

  16. Production of the alkaloid swainsonine by a fungal endosymbiont of the ascomycete order Chaetothyriales in the host Ipomoea carnea.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Some plant species within the Convolvulaceae (morning glory family) from South America, Africa, and Australia cause a neurologic disease in grazing livestock caused by swainsonine. These convolvulaceous species including Ipomoea carnea contain the indolizidine alkaloid swainsonine, an inhibitor of ...

  17. Genome and physiology of the ascomycete filamentous fungus Xeromyces bisporus, the most xerophilic organism isolated to date.

    PubMed

    Leong, Su-Lin L; Lantz, Henrik; Pettersson, Olga V; Frisvad, Jens C; Thrane, Ulf; Heipieper, Hermann J; Dijksterhuis, Jan; Grabherr, Manfred; Pettersson, Mats; Tellgren-Roth, Christian; Schnürer, Johan

    2015-02-01

    Xeromyces bisporus can grow on sugary substrates down to 0.61, an extremely low water activity. Its genome size is approximately 22 Mb. Gene clusters encoding for secondary metabolites were conspicuously absent; secondary metabolites were not detected experimentally. Thus, in its 'dry' but nutrient-rich environment, X. bisporus appears to have relinquished abilities for combative interactions. Elements to sense/signal osmotic stress, e.g. HogA pathway, were present in X. bisporus. However, transcriptomes at optimal (∼ 0.89) versus low aw (0.68) revealed differential expression of only a few stress-related genes; among these, certain (not all) steps for glycerol synthesis were upregulated. Xeromyces bisporus increased glycerol production during hypo- and hyper-osmotic stress, and much of its wet weight comprised water and rinsable solutes; leaked solutes may form a protective slime. Xeromyces bisporus and other food-borne moulds increased membrane fatty acid saturation as water activity decreased. Such modifications did not appear to be transcriptionally regulated in X. bisporus; however, genes modulating sterols, phospholipids and the cell wall were differentially expressed. Xeromyces bisporus was previously proposed to be a 'chaophile', preferring solutes that disorder biomolecular structures. Both X. bisporus and the closely related xerophile, Xerochrysium xerophilum, with low membrane unsaturation indices, could represent a phylogenetic cluster of 'chaophiles'. PMID:25142400

  18. An Aspergillus nidulans GH26 endo-β-mannanase with a novel degradation pattern on highly substituted galactomannans.

    PubMed

    von Freiesleben, Pernille; Spodsberg, Nikolaj; Blicher, Thomas Holberg; Anderson, Lars; Jørgensen, Henning; Stålbrand, Henrik; Meyer, Anne S; Krogh, Kristian B R M

    2016-02-01

    The activity and substrate degradation pattern of a novel Aspergillus nidulans GH26 endo-β-mannanase (AnMan26A) was investigated using two galactomannan substrates with varying amounts of galactopyranosyl residues. The AnMan26A was characterized in parallel with the GH26 endomannanase from Podospora anserina (PaMan26A) and three GH5 endomannanases from A. nidulans and Trichoderma reesei (AnMan5A, AnMan5C and TrMan5A). The initial rates and the maximal degree of enzymatically catalyzed conversion of locust bean gum and guar gum galactomannans were determined. The hydrolysis product profile at maximal degree of conversion was determined using DNA sequencer-Assisted Saccharide analysis in High throughput (DASH). This is the first reported use of this method for analyzing galactomannooligosaccharides. AnMan26A and PaMan26A were found to have a novel substrate degradation pattern on the two galactomannan substrates. On the highly substituted guar gum AnMan26A and PaMan26A reached 35-40% as their maximal degree of conversion whereas the three tested GH5 endomannanases only reached 8-10% as their maximal degree of conversion. α-Galactosyl-mannose was identified as the dominant degradation product resulting from AnMan26A and PaMan26A action on guar gum, strongly indicating that these two enzymes can accommodate galactopyranosyl residues in the -1 and in the +1 subsite. The degradation of α-6(4)-6(3)-di-galactosyl-mannopentaose by AnMan26A revealed accommodation of galactopyranosyl residues in the -2, -1 and +1 subsite of the enzyme. Accommodation of galactopyranosyl residues in subsites -2 and +1 has not been observed for other characterized endomannanases to date. Docking analysis of galactomannooligosaccharides in available crystal structures and homology models supported the conclusions drawn from the experimental results. This newly discovered diversity of substrate degradation patterns demonstrates an expanded functionality of fungal endomannanases, than hitherto

  19. The Mechanism of Toxicity in HET-S/HET-s Prion Incompatibility

    PubMed Central

    Seuring, Carolin; Greenwald, Jason; Wasmer, Christian; Wepf, Roger; Saupe, Sven J.; Meier, Beat H.; Riek, Roland

    2012-01-01

    The HET-s protein from the filamentous fungus Podospora anserina is a prion involved in a cell death reaction termed heterokaryon incompatibility. This reaction is observed at the point of contact between two genetically distinct strains when one harbors a HET-s prion (in the form of amyloid aggregates) and the other expresses a soluble HET-S protein (96% identical to HET-s). How the HET-s prion interaction with HET-S brings about cell death remains unknown; however, it was recently shown that this interaction leads to a relocalization of HET-S from the cytoplasm to the cell periphery and that this change is associated with cell death. Here, we present detailed insights into this mechanism in which a non-toxic HET-s prion converts a soluble HET-S protein into an integral membrane protein that destabilizes membranes. We observed liposomal membrane defects of approximately 10 up to 60 nm in size in transmission electron microscopy images of freeze-fractured proteoliposomes that were formed in mixtures of HET-S and HET-s amyloids. In liposome leakage assays, HET-S has an innate ability to associate with and disrupt lipid membranes and that this activity is greatly enhanced when HET-S is exposed to HET-s amyloids. Solid-state nuclear magnetic resonance (NMR) analyses revealed that HET-s induces the prion-forming domain of HET-S to adopt the β-solenoid fold (previously observed in HET-s) and this change disrupts the globular HeLo domain. These data indicate that upon interaction with a HET-s prion, the HET-S HeLo domain partially unfolds, thereby exposing a previously buried ∼34-residue N-terminal transmembrane segment. The liberation of this segment targets HET-S to the membrane where it further oligomerizes, leading to a loss of membrane integrity. HET-S thus appears to display features that are reminiscent of pore-forming toxins. PMID:23300377

  20. 50 CFR 10.13 - List of Migratory Birds.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., American, Recurvirostra americana BEAN-GOOSE, Taiga, Anser fabalis Tundra, Anser serrirostris BEARDLESS..., Fulvous Whistling-Duck Subfamily ANSERINAE Anser fabalis, Taiga Bean-Goose Anser serrirostris, Tundra...

  1. 50 CFR 10.13 - List of Migratory Birds.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., American, Recurvirostra americana BEAN-GOOSE, Taiga, Anser fabalis Tundra, Anser serrirostris BEARDLESS..., Fulvous Whistling-Duck Subfamily ANSERINAE Anser fabalis, Taiga Bean-Goose Anser serrirostris, Tundra...

  2. 50 CFR 10.13 - List of Migratory Birds.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., American, Recurvirostra americana BEAN-GOOSE, Taiga, Anser fabalis Tundra, Anser serrirostris BEARDLESS..., Fulvous Whistling-Duck Subfamily ANSERINAE Anser fabalis, Taiga Bean-Goose Anser serrirostris, Tundra...

  3. 50 CFR 10.13 - List of Migratory Birds.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., American, Recurvirostra americana BEAN-GOOSE, Taiga, Anser fabalis Tundra, Anser serrirostris BEARDLESS..., Fulvous Whistling-Duck Subfamily ANSERINAE Anser fabalis, Taiga Bean-Goose Anser serrirostris, Tundra...

  4. Draft Genome Sequence of the Deep-Sea Ascomycetous Filamentous Fungus Cadophora malorum Mo12 from the Mid-Atlantic Ridge Reveals Its Biotechnological Potential

    PubMed Central

    Rédou, Vanessa; Kumar, Abhishek; Hainaut, Matthieu; Henrissat, Bernard; Record, Eric; Barbier, Georges

    2016-01-01

    Cadophora malorum Mo12 was isolated from the Rainbow hydrothermal site on the Mid-Atlantic Ridge. We present the draft genome sequence of this filamentous fungal strain, which has high biotechnological potentials as revealed by the presence of genes encoding biotechnologically important enzymes and genes involved in the synthesis of secondary metabolites. PMID:27389260

  5. [Determination of LC 90 and LT 90 of IBCB66 Beauveria bassiana (Ascomycetes: Clavicipitaceae) isolate for Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) control].

    PubMed

    Barci, Leila A G; de Almeida, José Eduardo M; de Campos Nogueira, Adriana H; do Prado, Angelo P

    2009-12-01

    The objective of this research was to evaluate the pathogenicity and the virulence of the IBCB66 isolate of Beauveria bassiana on infected larvae of Rhipicephalus (Boophilus) microplus. The IBCB66 fungus strain was used as standard isolates of B. bassiana against R. (B.) microplus larvae. The larval bioassay tests using the IBCB66 isolate were carried out to determine the (Lethal Concentration) LC50, LC90, (Lethal Time) LT50 and LT90. The IBCB66 fungus strain was tested at six different concentrations (5x10(6), 10(7), 5x10(7), 10(8), 5x10(8) and 10(9) conidia.mL(-1)) to determine the percentage of larval mortality. In addition, a Probit analysis was also performed. Total larval mortality was observed eighteen days after the beginning of the test in the group treated with 5x10(9) conidia.mL(1). The LC50 and LC90 were 3x10(7) and 5x10(8) respectively and the LT50 and LT90 were 10 and 16 days. PMID:20040188

  6. Chemical Composition and Medicinal Value of Fruiting Bodies and Submerged Cultured Mycelia of Caterpillar Medicinal Fungus Cordyceps militaris CBS-132098 (Ascomycetes).

    PubMed

    Chan, Jannie Siew Lee; Barseghyan, Gayane S; Asatiani, Mikheil D; Wasser, Solomon P

    2015-01-01

    In this paper, we report the results of a proximate analysis (i.e., moisture, ash, protein, fat, carbohydrates, and energy); a bioactive compounds analysis (i.e., cordycepin and ergothioneine); fatty and amino acid analysis; and analyses of vitamin content, macro- and microelement composition of fruiting body (FB), and mycelial biomass (MB) of medicinal caterpillar fungus Cordyceps militaris strain CBS-132098. These results demonstrate that the FB and MB of C. militaris are good sources of proteins: 59.8% protein content in the FB and 39.5% in the MB. The MB was distinguished by its carbohydrate content (39.6%), which was higher than that of the FB (29.1% carbohydrate). In the FB of C. militaris, the total amino acid content was 57.39 mg/g and in the MB it was 24.98 mg/g. The quantification of the identified fatty acids indicated that palmitic acid, oleic acid, linoleic acid, and linolenic acid were the major fatty acids. The micro- and macroelement compositions were studied. The highest results were calcium (797 mg/kg FB; 11 mg/kg MB); potassium (15,938 mg/kg FB 12,183 mg/kg MB); magnesium (4,227 mg/kg FB; 3,414 mg/kg MB); sodium (171 mg/kg FB; 1,567 mg/kg MB); phosphorus (7,196 mg/kg FB; 14,293 mg/kg MB); and sulfur (5,088 mg/kg FB; 2,558 mg/kg MB). The vitamin composition was studied, and the most abundant vitamins were vitamin A, vitamin B3, and vitamin E. The bioactive components were cordycepin, cordycepic acid (D-mannitol), and ergothioneine. There were differences in cordycepin and ergothioneine contents between the FB and the MB. The cordycepin concentration was 0.11% in the FB and 0.182% in the MB, the cordycepic acid was 4.7 mg/100g in the FB and 5.2 mg/100 g in the MB, and the ergothioneine content was 782.37 mg/kg in the FB and 130.65 mg/kg in the MB. The nutritional values of the FB and the MB of C. militaris detected indicate its potential use in well-balanced diets and sources of bioactive compounds. PMID:26559699

  7. Phylogenetic analysis of ascomycete yeasts that form coenzyme Q-9 and the proposal of the new genera Babjeviella, Meyerozyma, Millerozyma, Priceomyces and Scheffersomyces

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Species assigned to the genera Debaryomyces, Lodderomyces, Spathaspora and Yamadazyma, as well as selected species of Pichia and Candida that also form coenzyme Q-9, were phylogenetically analyzed from the combined sequences of the D1/D2 domains of the large subunit and the small subunit rRNA genes....

  8. Identification of clinically important ascomycetous yeasts based on nucleotide divergence in the 5' end of the large-subunit (26S) ribosomal DNA gene.

    PubMed Central

    Kurtzman, C P; Robnett, C J

    1997-01-01

    Clinically important species of Candida and related organisms were compared for extent of nucleotide divergence in the 5' end of the large-subunit (26S) ribosomal DNA (rDNA) gene. This rDNA region is sufficiently variable to allow reliable separation of all known clinically significant yeast species. Of the 204 described species examined, 21 appeared to be synonyms of previously described organisms. Phylogenetic relationships among the species are presented. PMID:9114410

  9. NPS6, Encoding a Non-Ribosomal Peptide Synthetase Involved in Siderophore-Mediated Iron Metabolism, is a Conserved Virulence Determinant of Plant Pathogenic Ascomycetes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    NPS6, encoding a non-ribosomal peptide synthetase, is a virulence determinant in the corn pathogen Cochliobolus heterostrophus and is also involved in resistance to oxidative stress, generated by hydrogen peroxide. Deletion of NPS6 orthologs in the rice pathogen, Cochliobolus miyabeanus, the cereal...

  10. Trifluoromethanesulfonic acid-based proteomic analysis of cell wall and secreted proteins of the ascomycetous fungi Neurospora crassa and Candida albicans.

    PubMed

    Maddi, Abhiram; Bowman, Shaun M; Free, Stephen J

    2009-10-01

    Cell wall proteins from purified Candida albicans and Neurospora crassa cell walls were released using trifluoromethanesulfonic acid (TFMS) which cleaves the cell wall glucan/chitin matrix and deglycosylates the proteins. The cell wall proteins were then characterized by SDS-PAGE and identified by proteomic analysis. The analyses for C. albicans identified 15 cell wall proteins and six secreted proteins. For N. crassa, the analyses identified 26 cell wall proteins and nine secreted proteins. Most of the C. albicans cell wall proteins are found in the cell walls of both yeast and hyphae cells, but some cell type-specific cell wall proteins were observed. The analyses showed that the pattern of cell wall proteins present in N. crassa vegetative hyphae and conidia (asexual spores) are quite different. Almost all of the cell wall proteins identified in N. crassa have close homologs in the sequenced fungal genomes, suggesting that these proteins have important conserved functions within the cell wall. PMID:19555771

  11. SPORE-EXPULSION RATES AND EXTENTS OF BLADE OCCUPATION BY ASCOMYCETES OF THE SMOOTH-CORDGRASS STANDING-DECAY SYSTEM. (R825147)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  12. Isolation and purification of a polysaccharide from the caterpillar medicinal mushroom Cordyceps militaris (Ascomycetes) fruit bodies and its immunomodulation of RAW 264.7 macrophages.

    PubMed

    Zhu, Lina; Tang, Qingjiu; Zhou, Shuai; Liu, Yanfang; Zhang, Zhong; Gao, Xinhua; Wang, Shiping; Wang, Zhaolong

    2014-01-01

    A novel polysaccharide (CP2-S) was purified from Cordyceps militaris fruit bodies by hot water extraction, ethanol precipitation, DEAE-Sepharose Fast Flow and Sephacryl S-400 high-resolution chromatography. The polysaccharide had a molecular weight of 5.938 × 10(6) g/mol and was mainly composed of glucose. CP2-S had carbohydrate content estimated to be 100% using the phenol-sulfuric acid method. Immunostimulating experiments in vitro indicated that CP2-S could stimulate nitric oxide production, phagocytosis, respiratory burst activity, and secretion of interleukin-1β and interleukin-2 of macrophages, suggesting that this water-soluble polysaccharide from the fruit body of C. militaris is a natural immunostimulating polysaccharide with potential for further application. PMID:24941166

  13. Molecular, proteomic and morphological characterization of the ascomycete Guignardia bidwellii, agent of grape black rot: a polyphasic approach to fungal identification.

    PubMed

    Wicht, Barbara; Petrini, Orlando; Jermini, Mauro; Gessler, Cesare; Broggini, Giovanni Antonio Lodovico

    2012-01-01

    Guignardia bidwellii is the etiological agent of grape black rot, a disease affecting Vitis and other Vitaceae that can cause heavy crop losses in vineyards. Its identification is based mainly on morphological characters and the symptoms on plants but, due to their variability, they may be difficult to interpret to reliably distinguish the pathogen to species. To date, despite the economic importance of G. bidwellii, no molecular investigations have been carried out on Vitis isolates and few sequence data are available for cultures derived from ornamental host plants. We analyzed samples of G. bidwellii collected from grapevine cultivars and ornamental plants of various geographic origins by morphological, molecular and proteomic techniques, including ITS1-ITS2 regions and calmodulin gene sequencing, as well as matrix-assisted laser desorption/ionization analysis by time-of-flight mass spectrometry (MALDI-TOF MS). This polyphasic approach allowed assessing the phylogenetic relationships among the different isolates and suggested the existence of two distinct species. The advantages of a polyphasic approach for the identification of G. bidwellii are highlighted. PMID:22492405

  14. Cloning of mating-type gene MAT1-1 from the caterpillar medicinal mushroom, Cordyceps militaris (Ascomycetes) using TAIL-PCR technology.

    PubMed

    Cong, Wei-Ran; Gong, Zhen-Hua; Shi, Dan-Dan; Guo, Hui; Zhou, Xuanwei

    2014-01-01

    Cordyceps militaris and Ophiocordyceps sinensis (syn. Cordyceps sinensis), 2 well-known traditional Chinese medicines, contain the same bioactive components and share a similar developmental process. In this study, one C. militaris strain preserved in our laboratory was proven to be a MAT1 mating-type strain using a polymerase chain reaction-based mating-type assay. A 5000-bp nucleotide sequence of the mating-type MAT1-1 from C. militaris was amplified by thermal asymmetric interlaced polymerase chain reaction, but genes within the mating-type MAT1-2 remain undetectable. Sequence analysis shows that the mating-type gene MAT1-1 idiomorph contains 2 genes, MAT1-1-1 and MAT1-1-2. The MAT1-1-1 gene consists of 1480-bp nucleotides that encode 456 amino acids and contain the conserved a-box domain interrupted by 2 introns; the MAT1-1-2 gene consists of 1066 nucleotides that encode 377 amino acids interrupted by one intron. The intervening distance between MAT1-1-1 and MAT1-1-2 is 778 bp. The C. militaris MAT1-1 idiomorph organization is the same as that of Cordyceps takaomontana. The MAT1-1 mating-type idiomorph of both Cordyceps species lacks the MAT1-1-3 gene, which is typically present in Pyrenomycetes. These studies provide some insights for further study of the morphological development of C. militaris and will eventually benefit the domestication of O. sinensis. PMID:25271980

  15. Molecular Markers to Detect the Formation of Heterokaryon and Homokaryon from Asexual Spores of the Caterpillar Medicinal Mushroom, Cordyceps militaris (Ascomycetes).

    PubMed

    Wang, Hong; Cai, Tao; Wei, Jing; Feng, Aiping; Lin, Nan; Bao, Dapeng

    2015-01-01

    Cordyceps militaris is widely cultivated on artificial media in China; however, the cultures often are afflicted with the degeneration of nonfruiting strains. To understand the mechanism of degeneration of C. militaris, from the heterokaryotic strain into the homokaryotic strain, we examined the mating-type genes present in individual asexual spores. Further, we determined the distribution ratio of the different mating-type genes among a sample of asexual spores and the growth rate of heterokaryotic and homokaryotic strains of C. militaris. The distribution ratio of 3 groups of asexual spores from C. militaris heterokaryotic strains was determined as 1:1:1 by statistical analysis, whereas that of the two types of nuclei among asexual spores was 1:1. Nearly two-thirds of the asexual spore isolates were homokaryon, which showed a growth speed similar to the heterokaryon. However, the homokaryon (bearing mating-type MAT-HMG) grew significantly faster at times compared with the heterokaryon. Therefore, the purity of the spawn was difficult to establish. C. militaris heterokaryotic strains can transform into a homokaryotic strain following continued subculture. PMID:26756296

  16. A comparative study of the antimicrobial, antioxidant, and cytotoxic activities of methanol extracts from fruit bodies and fermented mycelia of caterpillar medicinal mushroom Cordyceps militaris (Ascomycetes).

    PubMed

    Dong, Cai-Hong; Yang, Tao; Lian, Tiantian

    2014-01-01

    Cordyceps militaris is one of the most popular mushrooms and nutraceuticals in Eastern Asia. This study assayed and compared the antimicrobial, antioxidant, and cytotoxic properties of the methanol extracts from fruiting bodies and fermented mycelia of C. militaris, as well as the contents of total phenol, flavonoids, and cordycepin. The results showed that the extracts from fruiting bodies possessed broad antimicrobial activities against all microorganisms tested (both bacteria and fungi), whereas that from the fermented mycelia showed selective activity. The antioxidant potential of two extracts is significant in the four tested systems in vitro, including total antioxidant capacity, scavenging abilities on 1,1-diphenyl-2-picrylhydrazyl (DPPH·) radicals, reducing power, and chelating ability on ferrous ions. The fruiting bodies had stronger DPPH· radical scavenging activity, whereas the fermented mycelia had stronger total antioxidant capacity, chelating ability, and reducing power, which suggested that they had their own role and worked in different ways. Both extracts present strong activities against tumor cell line A549. The results obtained indicated that extracts from C. militaris might be valuable antimicrobial, antioxidant, and cytotoxic natural sources and seemed to be applicable in health and medicine as well as in the food industry. PMID:25271983

  17. Mitochondrial Carnitine-Dependent Acetyl Coenzyme A Transport Is Required for Normal Sexual and Asexual Development of the Ascomycete Gibberella zeae

    PubMed Central

    Son, Hokyoung; Min, Kyunghun; Lee, Jungkwan; Choi, Gyung Ja; Kim, Jin-Cheol

    2012-01-01

    Fungi have evolved efficient metabolic mechanisms for the exact temporal (developmental stages) and spatial (organelles) production of acetyl coenzyme A (acetyl-CoA). We previously demonstrated mechanistic roles of several acetyl-CoA synthetic enzymes, namely, ATP citrate lyase and acetyl-CoA synthetases (ACSs), in the plant-pathogenic fungus Gibberella zeae. In this study, we characterized two carnitine acetyltransferases (CATs; CAT1 and CAT2) to obtain a better understanding of the metabolic processes occurring in G. zeae. We found that CAT1 functioned as an alternative source of acetyl-CoA required for lipid accumulation in an ACS1 deletion mutant. Moreover, deletion of CAT1 and/or CAT2 resulted in various defects, including changes to vegetative growth, asexual/sexual development, trichothecene production, and virulence. Although CAT1 is associated primarily with peroxisomal CAT function, mislocalization experiments showed that the role of CAT1 in acetyl-CoA transport between the mitochondria and cytosol is important for sexual and asexual development in G. zeae. Taking these data together, we concluded that G. zeae CATs are responsible for facilitating the exchange of acetyl-CoA across intracellular membranes, particularly between the mitochondria and the cytosol, during various developmental stages. PMID:22798392

  18. Mycelial fermentation characteristics and anti-fatigue activities of a Chinese caterpillar fungus, Ophiocordyceps sinensis strain Cs-HK1 (Ascomycetes).

    PubMed

    Wu, Jian-Yong; Leung, Hong-Po; Wang, Wen-Qiang; Xu, Chunping

    2014-01-01

    Mycelial fermentation of an Ophiocordyceps sinensis strain Cs-HK1 was carried out in various volumes of stirred-tank fermenters from 1.6-L and 15-L laboratory scale to 2000-L industrial scale. The mycelial growth in most fermenters had a higher rate, due probably to more efficient oxygen supply, than in shake-flasks. The mycelial fermentation was successfully scaled up to 2000-L industrial fermenters, achieving 30 g/L maximum biomass in 5 days. The Cs-HK1 mycelia formed hairy and fluffy pellets in the fermentation medium and the mycelial broth exhibited pseudoplastic rheology following the power law, with the flow behavior index n decreasing from 0.5 to 0.3, and the flow consistency K and the apparent viscosity µα increasing with time and biomass concentration. The mycelial broth containing biomass and extracellular products harvested from 2000-L fermenters was tested for anti-fatigue activities in forced animal swimming experiments. The mycelium hot water extract showed the most significant effects, increasing the swimming endurance of mice up to 100%, and also increasing the glycogen levels and reducing the lactic acid and blood urea nitrogen levels significantly. The results demonstrated the feasibility of Cs-HK1 mycelial fermentation for large-scale production of bioactive and medicinal materials. PMID:24941032

  19. Comparison of Major Bioactive Compounds of the Caterpillar Medicinal Mushroom, Cordyceps militaris (Ascomycetes), Fruiting Bodies Cultured on Wheat Substrate and Pupae.

    PubMed

    Guo, Mingmin; Guo, Suping; Huaijun, Yang; Bu, Ning; Dong, Cai-Hong

    2016-01-01

    In this study, the main bioactive compounds of the fruit bodies of Cordyceps militaris-such as adenosine, cordycepin, polysaccharides, mannitol, superoxide dismutase (SOD), and carotenoids-were cultivated on wheat and pupae, as well as sclerotium (the pupae portion) and sclerotium with fruiting bodies. The amounts of adenosine and polysaccharide in all the tested samples (except for the polysaccharides of sclerotium) are higher than the quality standards (adenosine ≥0.055% and polysaccharide ≥2.5%) determined by the Ministry of Health of the People's Republic of China. As the most important bioactive compound in C. militaris, cordycepin is the highest in the fruiting bodies on pupae than in other samples, whereas it is the lowest in the sclerotium. The amounts of cordycepin, carotenoids, and SOD were higher in the fruiting bodies on pupae than that in the fruiting bodies on wheat, whereas the amounts of adenosine, polysaccharides, and mannitol were higher in the fruiting bodies on wheat than in the fruiting bodies on pupae. There was no significant difference in the amounts of cordycepin, carotenoids, and SOD in the sclerotium with fruiting bodies and the fruiting bodies on wheat. The adenosine, polysaccharide, and mannitol contents in the sclerotium with fruiting bodies were significantly lower than those of the fruiting bodies on wheat. Overall, the results of this evaluation could not distinguish which is better: the fruiting bodies on pupae or those on wheat; each has its own merits. The fruiting bodies of C. militaris cultivated on both wheat and pupae are important candidates for medicinal and tonic use for the welfare of humankind. PMID:27481299

  20. The phylogenetic analysis of fungi associated with lichenized ascomycete genus Bryoria reveals new lineages in the Tremellales including a new species Tremella huuskonenii hyperparasitic on Phacopsis huuskonenii.

    PubMed

    Lindgren, Hanna; Diederich, Paul; Goward, Trevor; Myllys, Leena

    2015-09-01

    The basidiomycete order Tremellales includes many species parasitic on or cohabiting with lichen-forming fungi. In this study, we examined the phylogenetic position of Tremellales obtained from Bryoria thalli using nSSU, 5.8S, and partial nLSU sequence data. Both Bayesian and maximum likelihood analyses revealed the presence of basidiomycetous fungi in three separate clades within Tremellales. Tremellales sp. A and Tremella sp. B exist asymptomatically in Bryoria thalli and should thus be regarded as endolichenic rather than lichenicolous fungi. The third lineage represents a new species and is described here as Tremella huuskonenii. It is hyperparasitic over galls induced by Phacopsis huuskonenii, a lichenicolous fungus growing in Bryoria thalli. We also examined the genetic diversity of Tremella sp. B and Tremella huuskonenii with an extended taxon sampling using ITS and partial nLSU sequence data. For comparison, ITS, GAPDH, and Mcm7 regions were used for phylogenetic analyses of the host lichen specimens. According to our results, phylogenetic structure within the two Tremella species does not appear to correlate with the geographic distribution nor with the phylogeny or the secondary chemistry of the host lichen. However, ITS haplotype analysis of T. huuskonenii revealed some genetic differences between European and North American populations as some haplotypes were more common in Europe than in North America and vice versa. PMID:26321732

  1. Draft Genome Sequence of the Deep-Sea Ascomycetous Filamentous Fungus Cadophora malorum Mo12 from the Mid-Atlantic Ridge Reveals Its Biotechnological Potential.

    PubMed

    Rédou, Vanessa; Kumar, Abhishek; Hainaut, Matthieu; Henrissat, Bernard; Record, Eric; Barbier, Georges; Burgaud, Gaëtan

    2016-01-01

    Cadophora malorum Mo12 was isolated from the Rainbow hydrothermal site on the Mid-Atlantic Ridge. We present the draft genome sequence of this filamentous fungal strain, which has high biotechnological potentials as revealed by the presence of genes encoding biotechnologically important enzymes and genes involved in the synthesis of secondary metabolites. PMID:27389260

  2. Aging as Evolution-Facilitating Program and a Biochemical Approach to Switch It Off

    NASA Astrophysics Data System (ADS)

    Skulachev, Vladimir P.

    decelerates the development of three types of accelerated aging (progeria) and also of normal aging, and this effect is especially demonstrative at early stages of aging. The same pattern is shown in invertebrates (Drosophila and Daphnia), and fungus (Podospora anserina). In mammals, the effect of SkQs on aging is accompanied by inhibition of development of such age-related diseases as osteoporosis, involution of thymus, cataract, retinopathy, etc. SkQ1 manifests a strong therapeutic action on some already pronounced retinopathies, in particular, congenital retinal dysplasia. With drops containing 250 nM SkQ1, vision is recovered in 66 of 96 animals (dogs, cats and horses) who became blind because of retinopathy. SkQ1-containing drops instilled into eyes prevent the loss of sight in rabbits suffering from experimental uveitis and restore vision to animals that had already become blind due to this pathology. A favorable effect is also achieved in experimental glaucoma in rabbits. Moreover, the pretreatment of rats with 0.2 nM SkQ1 significantly decreases the H2O2-induced arrhythmia of the isolated heart. SkQ1 strongly reduces the damaged area in myocardial infarction or stroke and prevents the death of animals from kidney infarction. In p53-/- mice, SkQ1 decreases the ROS level in the spleen cells and inhibits appearance of lymphomas which are the main cause of death of such animals. As a result, the lifespan increases. SkQs look like promising drugs to treat aging and age-related diseases.

  3. 50 CFR 10.13 - List of Migratory Birds.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., Aethia pygmaea AVOCET, American, Recurvirostra americana BEAN-GOOSE, Taiga, Anser fabalis Tundra, Anser... Taiga, Ficedula albicilla Tufted, Mitrephanes phaeocercus Variegated, Empidonomus varius Vermilion... Subfamily ANSERINAE Anser fabalis, Taiga Bean-Goose Anser serrirostris, Tundra Bean-Goose Anser...

  4. Laccase production by the aquatic ascomycete Phoma sp. UHH 5-1-03 and the white rot basidiomycete Pleurotus ostreatus DSM 1833 during submerged cultivation on banana peels and enzyme applicability for the removal of endocrine-disrupting chemicals.

    PubMed

    Libardi, Nelson; Gern, Regina Maria Miranda; Furlan, Sandra Aparecida; Schlosser, Dietmar

    2012-07-01

    This work aimed to study the production of laccase from Pleurotus ostreatus DSM 1833 and Phoma sp. UHH 5-1-03 using banana peels as alternative carbon source, the subsequent partial purification and characterization of the enzyme, as well the applicability to degrade endocrine disruptors. The laccase stability with pH and temperature, the optimum pH, the K (m) and V(max) parameters, and the molar mass were determined. Tests were conducted for assessing the ability of degradation of the endocrine disruptors t-nonylphenol, bisphenol A, and 17α-ethinylestradiol. Laccase production of 752 and 1,117 U L⁻¹ was obtained for Phoma sp. and P. ostreatus, respectively. Phoma sp. laccase showed higher stability with temperature and pH. The laccase from both species showed higher affinity by syringaldazine. The culture broth with banana peels induced the production of two isoforms of P. ostreatus (58.7 and 21 kDa) and one of Phoma sp. laccase (72 kDa). In the first day of incubation, the concentrations of bisphenol A and 17α-ethinylestradiol were reduced to values close to zero and after 3 days the concentration of t-nonylphenol was reduced in 90% by the P. ostreatus laccase, but there was no reduction in its concentration by the Phoma sp. laccase. PMID:22371062

  5. The Wood Rot Ascomycete Xylaria polymorpha Produces a Novel GH78 Glycoside Hydrolase That Exhibits α-l-Rhamnosidase and Feruloyl Esterase Activities and Releases Hydroxycinnamic Acids from Lignocelluloses

    PubMed Central

    Nghi, Do Huu; Bittner, Britta; Kellner, Harald; Jehmlich, Nico; Ullrich, René; Pecyna, Marek J.; Nousiainen, Paula; Sipilä, Jussi; Huong, Le Mai; Hofrichter, Martin

    2012-01-01

    Soft rot (type II) fungi belonging to the family Xylariaceae are known to substantially degrade hardwood by means of their poorly understood lignocellulolytic system, which comprises various hydrolases, including feruloyl esterases and laccase. In the present study, several members of the Xylariaceae were found to exhibit high feruloyl esterase activity during growth on lignocellulosic materials such as wheat straw (up to 1,675 mU g−1) or beech wood (up to 80 mU g−1). Following the ester-cleaving activity toward methyl ferulate, a hydrolase of Xylaria polymorpha was produced in solid-state culture on wheat straw and purified by different steps of anion-exchange and size-exclusion chromatography to apparent homogeneity (specific activity, 2.2 U mg−1). The peptide sequence of the purified protein deduced from the gene sequence and verified by de novo peptide sequencing shows high similarity to putative α-l-rhamnosidase sequences belonging to the glycoside hydrolase family 78 (GH78; classified under EC 3.2.1.40). The purified enzyme (98 kDa by SDS-PAGE, 103 kDa by size-exclusion chromatography; pI 3.7) converted diverse glycosides (e.g., α-l-rhamnopyranoside and α-l-arabinofuranoside) but also natural and synthetic esters (e.g., chlorogenic acid, hydroxycinnamic acid glycoside esters, veratric acid esters, or p-nitrophenyl acetate) and released free hydroxycinnamic acids (ferulic and coumaric acid) from arabinoxylan and milled wheat straw. These catalytic properties strongly suggest that X. polymorpha GH78 is a multifunctional enzyme. It is the first fungal enzyme that combines glycosyl hydrolase with esterase activities and may help this soft rot fungus to degrade lignocelluloses. PMID:22544251

  6. Yippie Yi Yo Mycota Ki Yay! A mycologist’s fervently biased account of how the American western frontier was molded by spores and mycelium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Discussed are white pine blister rust (Cronartium ribicola), cereal rusts (Puccinia spp.), smuts (Tilletia spp.), fungi as agents of recycling in grasslands (e.g., Sporormiella and Podospora spp.), fungal symbionts of bark beetles (e.g., Ophiostoma spp.), impacts of clinical fungi (e.g., Valley Feve...

  7. A new species of Jahnulales from Las Ilusiones Lagoon, Tabasco, Mexico

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During a study on biodiversity of freshwater ascomycetes from an urban tropical lagoon, an ascomycete with similar morphology to species of Jahnulales was obtained. Smooth surface test blocks of Pinus sp., Bucida sp., Cedrela sp. and Tabebuia sp. were submerged in pairs close to a private house whar...

  8. Genetic structure of the fungal grapevine pathogen Eutypa lata from four continents

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The generalist ascomycete fungus Eutypa lata causes Eutypa dieback of grapevine (Vitis vinifera) worldwide. To decipher the cosmopolitan distribution of this fungus, the population genetic structure of 17 geographic samples was investigated from four continental regions (Australia, California, Europ...

  9. Relationships among genera of the Saccharomycotina from multigene sequence analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Most known species of the subphylum Saccharomycotina (budding ascomycetous yeasts) have now been placed in phylogenetically defined clades following multigene sequence analysis. Terminal clades, which are usually well supported from bootstrap analysis, are viewed as phylogenetically circumscribed ge...

  10. Genetic structure of the fungal grapevine pathogen Eutypa lata from four continents

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Deciphering the geographic origins of pathogens and elucidating the population biology of these microscopic organisms are necessary steps to establish effective disease-control strategies. The generalist ascomycete fungus Eutypa lata causes Eutypa dieback of grapevine (Vitis vinifera) worldwide. To ...