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Sample records for ascomycete podospora anserina

  1. Systematic Deletion of Homeobox Genes in Podospora anserina Uncovers Their Roles in Shaping the Fruiting Body

    PubMed Central

    Coppin, Evelyne; Berteaux-Lecellier, Véronique; Bidard, Frédérique; Brun, Sylvain; Ruprich-Robert, Gwenaël; Espagne, Eric; Aďt-Benkhali, Jinane; Goarin, Anne; Nesseir, Audrey; Planamente, Sara; Debuchy, Robert; Silar, Philippe

    2012-01-01

    Higher fungi, which comprise ascomycetes and basidiomycetes, play major roles in the biosphere. Their evolutionary success may be due to the extended dikaryotic stage of their life cycle, which is the basis for their scientific name: the Dikarya. Dikaryosis is maintained by similar structures, the clamp in basidiomycetes and the crozier in ascomycetes. Homeodomain transcription factors are required for clamp formation in all basidiomycetes studied. We identified all the homeobox genes in the filamentous ascomycete fungus Podospora anserina and constructed deletion mutants for each of these genes and for a number of gene combinations. Croziers developed normally in these mutants, including those with up to six deleted homeogenes. However, some mutants had defects in maturation of the fruiting body, an effect that could be rescued by providing wild-type maternal hyphae. Analysis of mutants deficient in multiple homeogenes revealed interactions between the genes, suggesting that they operate as a complex network. Similar to their role in animals and plants, homeodomain transcription factors in ascomycetes are involved in shaping multicellular structures. PMID:22662159

  2. The Transcriptional Response to Nonself in the Fungus Podospora anserina

    PubMed Central

    Bidard, Frédérique; Clavé, Corinne; Saupe, Sven J.

    2013-01-01

    In fungi, heterokaryon incompatibility is a nonself recognition process occurring when filaments of different isolates of the same species fuse. Compatibility is controlled by so-called het loci and fusion of strains of unlike het genotype triggers a complex incompatibility reaction that leads to the death of the fusion cell. Herein, we analyze the transcriptional changes during the incompatibility reaction in Podospora anserina. The incompatibility response was found to be associated with a massive transcriptional reprogramming: 2231 genes were up-regulated by a factor 2 or more during incompatibility. In turn, 2441 genes were down-regulated. HET, NACHT, and HeLo domains previously found to be involved in the control of heterokaryon incompatibility were enriched in the up-regulated gene set. In addition, incompatibility was characterized by an up-regulation of proteolytic and other hydrolytic activities, of secondary metabolism clusters and toxins and effector-like proteins. The up-regulated set was found to be enriched for proteins lacking orthologs in other species and chromosomal distribution of the up-regulated genes was uneven with up-regulated genes residing preferentially in genomic islands and on chromosomes IV and V. There was a significant overlap between regulated genes during incompatibility in P. anserina and Neurospora crassa, indicating similarities in the incompatibility responses in these two species. Globally, this study illustrates that the expression changes occurring during cell fusion incompatibility in P. anserina are in several aspects reminiscent of those described in host-pathogen or symbiotic interactions in other fungal species. PMID:23589521

  3. Poly(ADP-Ribose) Polymerase Is a Substrate Recognized by Two Metacaspases of Podospora anserina

    PubMed Central

    Strobel, Ingmar

    2013-01-01

    The two metacaspases MCA1 and MCA2 of the fungal aging model organism Podospora anserina (PaMCA1 and PaMCA2, respectively) have previously been demonstrated to be involved in the control of programmed cell death (PCD) and life span. In order to identify specific pathways and components which are controlled by the activity of these enzymes, we set out to characterize them further. Heterologous overexpression in Escherichia coli of the two metacaspase genes resulted in the production of proteins which aggregate and form inclusion bodies from which the active protein has been recovered via refolding in appropriate buffers. The renaturated proteins are characterized by an arginine-specific activity and are active in caspase-like self-maturation leading to the generation of characteristic small protein fragments. Both activities are dependent on the presence of calcium. Incubation of the two metacaspases with recombinant poly(ADP-ribose) polymerase (PARP), a known substrate of mammalian caspases, led to the identification of PARP as a substrate of the two P. anserina proteases. Using double mutants in which P. anserina Parp (PaParp) is overexpressed and PaMca1 is either overexpressed or deleted, we provide evidence for in vivo degradation of PaPARP by PaMCA1. These results support the idea that the substrate profiles of caspases and metacaspases are at least partially overlapping. Moreover, they link PCD and DNA maintenance in the complex network of molecular pathways involved in aging and life span control. PMID:23584991

  4. A unique CE16 acetyl esterase from Podospora anserina active on polymeric xylan.

    PubMed

    Puchart, Vladimír; Berrin, Jean-Guy; Haon, Mireille; Biely, Peter

    2015-12-01

    The genome of the coprophilous fungus Podospora anserina displays an impressive array of genes encoding hemicellulolytic enzymes. In this study, we focused on a putative carbohydrate esterase (CE) from family 16 (CE16) that bears a carbohydrate-binding module from family CBM1. The protein was heterologously expressed in Pichia pastoris and purified to electrophoretic homogeneity. The P. anserina CE16 enzyme (PaCE16A) exhibited different catalytic properties than so far known CE16 esterases represented by the Trichoderma reesei CE16 acetyl esterase (TrCE16). A common property of both CE16 esterases is their exodeacetylase activity, i.e., deesterification at positions 3 and 4 of monomeric xylosides and the nonreducing end xylopyranosyl (Xylp) residue of oligomeric homologues. However, the PaCE16A showed lower positional specificity than TrCE16 and efficiently deacetylated also position 2. The major difference observed between PaCE16A and TrCE16 was found on polymeric substrate, acetylglucuronoxylan. While TrCE16 does not attack internal acetyl groups, PaCE16A deacetylated singly and doubly acetylated Xylp residues in the polymer to such an extent that it resulted in the polymer precipitation. Similarly as typical acetylxylan esterases belonging to CE1, CE4, CE5, and CE6 families, PaCE16A did not attack 3-O-acetyl group of xylopyranosyl residues carrying 4-O-methyl-D-glucuronic acid at position 2. PaCE16A thus represents a CE16 member displaying unique catalytic properties, which are intermediate between the TrCE16 exodeacetylase and acetylxylan esterases designed to deacetylate polymeric substrate. The catalytic versatility of PaCE16A makes the enzyme an important candidate for biotechnological applications. PMID:26329850

  5. Identification of a Hypothetical Protein from Podospora anserina as a Nitroalkane Oxidase

    SciTech Connect

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

    2010-08-23

    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{sub cat}/K{sub M}-pH profile with nitroethane shows a pK{sub a} of 5.9 that is assigned to Asp399 as the active site base. Mutation of Asp399 to asparagine decreases the k{sub cat}/K{sub 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 {angstrom}, confirming its identification as an NAO.

  6. The proteasome activity reporter GFP-Cl1 is degraded by autophagy in the aging model Podospora anserina.

    PubMed

    Wiemer, Matthias; Osiewacz, Heinz D

    2014-01-01

    The degradation of damaged proteins is an important vital function especially during aging and stress. The ubiquitin proteasome system is one of the major cellular machineries for protein degradation. Health and longevity are associated with high proteasome activity. To demonstrate such a role in aging of Podospora anserina, we first analyzed the transcript and protein abundance of selected proteasome components in wild-type cultures of different age. No significant differences were observed. Next, in order to increase the overall proteasome abundance we generated strains overexpressing the catalytic proteasome subunits PaPRE2 and PaPRE3. Although transcript levels were strongly increased, no substantial effect on the abundance of the corresponding proteins was observed. Finally, the analysis of the P. anserina strains expressing the sequence coding for the CL1 degron fused to the Gfp gene revealed no evidence for degradation of the GFP-CL1 fusion protein by the proteasome. Instead, our results demonstrate the degradation of the CL1-degron sequence via autophagy, indicating that basal autophagy appears to be a very effective protein quality control pathway in P. anserina. PMID:25520781

  7. The proteasome activity reporter GFP-Cl1 is degraded by autophagy in the aging model Podospora anserina

    PubMed Central

    Wiemer, Matthias; Osiewacz, Heinz D.

    2014-01-01

    The degradation of damaged proteins is an important vital function especially during aging and stress. The ubiquitin proteasome system is one of the major cellular machineries for protein degradation. Health and longevity are associated with high proteasome activity. To demonstrate such a role in aging of Podospora anserina, we first analyzed the transcript and protein abundance of selected proteasome components in wild-type cultures of different age. No significant differences were observed. Next, in order to increase the overall proteasome abundance we generated strains overexpressing the catalytic proteasome subunits PaPRE2 and PaPRE3. Although transcript levels were strongly increased, no substantial effect on the abundance of the corresponding proteins was observed. Finally, the analysis of the P. anserina strains expressing the sequence coding for the CL1 degron fused to the Gfp gene revealed no evidence for degradation of the GFP-CL1 fusion protein by the proteasome. Instead, our results demonstrate the degradation of the CL1-degron sequence via autophagy, indicating that basal autophagy appears to be a very effective protein quality control pathway in P. anserina. PMID:25520781

  8. Does autophagy mediate age-dependent effect of dietary restriction responses in the filamentous fungus Podospora anserina?

    PubMed Central

    van Diepeningen, Anne D.; Engelmoer, Daniël J. P.; Sellem, Carole H.; Huberts, Daphne H. E. W.; Slakhorst, S. Marijke; Sainsard-Chanet, Annie; Zwaan, Bas J.; Hoekstra, Rolf F.; Debets, Alfons J. M.

    2014-01-01

    Autophagy is a well-conserved catabolic process, involving the degradation of a cell's own components through the lysosomal/vacuolar machinery. Autophagy is typically induced by nutrient starvation and has a role in nutrient recycling, cellular differentiation, degradation and programmed cell death. Another common response in eukaryotes is the extension of lifespan through dietary restriction (DR). We studied a link between DR and autophagy in the filamentous fungus Podospora anserina, a multicellular model organism for ageing studies and mitochondrial deterioration. While both carbon and nitrogen restriction extends lifespan in P. anserina, the size of the effect varied with the amount and type of restricted nutrient. Natural genetic variation for the DR response exists. Whereas a switch to carbon restriction up to halfway through the lifetime resulted in extreme lifespan extension for wild-type P. anserina, all autophagy-deficient strains had a shorter time window in which ageing could be delayed by DR. Under nitrogen limitation, only PaAtg1 and PaAtg8 mediate the effect of lifespan extension; the other autophagy-deficient mutants PaPspA and PaUth1 had a similar response as wild-type. Our results thus show that the ageing process impinges on the DR response and that this at least in part involves the genetic regulation of autophagy. PMID:24864315

  9. 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

  10. 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 senDNA? (a circular double-stranded DNA plasmid derived from the first intron of the mitochondrial cox1 gene or intron ?) 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 senDNA? 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 ? plays the role of the cytoplasmic and infectious Determinant of Senescence that was defined in early studies. PMID:9055079

  11. A Non-Mendelian MAPK-Generated Hereditary Unit Controlled by a Second MAPK Pathway in Podospora anserina

    PubMed Central

    Lalucque, Hervé; Malagnac, Fabienne; Brun, Sylvain; Kicka, Sébastien; Silar, Philippe

    2012-01-01

    The Podospora anserina PaMpk1 MAP kinase (MAPK) signaling pathway can generate a cytoplasmic and infectious element resembling prions. When present in the cells, this C element causes the crippled growth (CG) cell degeneration. CG results from the inappropriate autocatalytic activation of the PaMpk1 MAPK pathway during growth, whereas this cascade normally signals stationary phase. Little is known about the control of such prion-like hereditary units involved in regulatory inheritance. Here, we show that another MAPK pathway, PaMpk2, is crucial at every stage of the fungus life cycle, in particular those controlled by PaMpk1 during stationary phase, which includes the generation of C. Inactivation of the third P. anserina MAPK pathway, PaMpk3, has no effect on the development of the fungus. Mutants of MAPK, MAPK kinase, and MAPK kinase kinase of the PaMpk2 pathway are unable to present CG. This inability likely relies upon an incorrect activation of PaMpk1, although this MAPK is normally phosphorylated in the mutants. In PaMpk2 null mutants, hyphae are abnormal and PaMpk1 is mislocalized. Correspondingly, stationary phase differentiations controlled by PaMpk1 are defective in the mutants of the PaMpk2 cascade. Constitutive activation of the PaMpk2 pathway mimics in many ways its inactivation, including an effect on PaMpk1 localization. Analysis of double and triple mutants inactivated for two or all three MAPK genes undercover new growth and differentiation phenotypes, suggesting overlapping roles. Our data underscore the complex regulation of a prion-like element in a model organism. PMID:22426880

  12. Systematic gene deletions evidences that laccases are involved in several stages of wood degradation in the filamentous fungus Podospora anserina.

    PubMed

    Xie, Ning; Chapeland-Leclerc, Florence; Silar, Philippe; Ruprich-Robert, Gwenaël

    2014-01-01

    Transformation of plant biomass into biofuels may supply environmentally friendly alternative biological sources of energy. Laccases are supposed to be involved in the lysis of lignin, a prerequisite step for efficient breakdown of cellulose into fermentable sugars. The role in development and plant biomass degradation of the nine canonical laccases belonging to three different subfamilies and one related multicopper oxidase of the Ascomycota fungus Podospora anserina was investigated by targeted gene deletion. The 10 genes were inactivated singly, and multiple mutants were constructed by genetic crosses. lac6(?), lac8(?) and mco(?) mutants were significantly reduced in their ability to grow on lignin-containing materials, but also on cellulose and plastic. Furthermore, lac8(?), lac7(?), mco(?) and lac6(?) mutants were defective towards resistance to phenolic substrates and H2 O2 , which may also impact lignocellulose breakdown. Double and multiple mutants were generally more affected than single mutants, evidencing redundancy of function among laccases. Our study provides the first genetic evidences that laccases are major actors of wood utilization in a fungus and that they have multiple roles during this process apart from participation in lignin lysis. PMID:24102726

  13. Mating-Type Genes from the Homothallic Fungus Sordaria Macrospora Are Functionally Expressed in a Heterothallic Ascomycete

    PubMed Central

    Poggeler, S.; Risch, S.; Kuck, U.; Osiewacz, H. D.

    1997-01-01

    Homokaryons from the homothallic ascomycte Sordaria macrospora are able to enter the sexual pathway and to form fertile fruiting bodies. To analyze the molecular basis of homothallism and to elucidate the role of mating-products during fruiting body development, we cloned and sequenced the entire S. macrospora mating-type locus. Comparison of the Sordaria mating-type locus with mating-type idiomorphs from the heterothallic ascomycetes Neurospora crassa and Podospora anserina revealed that sequences from both idiomorphs (A/a and mat-/mat+, respectively) are contiguous in S. macrospora. DNA sequencing of the S. macrospora mating-type region allowed the identification of four open reading frames (ORFs), which were termed Smt-a1, SmtA-1, SmtA-2 and SmtA-3. While Smt-a1, SmtA-1, and SmtA-2 show strong sequence similarities with the corresponding N. crassa mating-type ORFs, SmtA-3 has a chimeric character. It comprises sequences that are similar to the A and a mating-type idiomorph from N. crassa. To determine functionality of the S. macrospora mating-type genes, we show that all ORFs are transcriptionally expressed. Furthermore, we transformed the S. macrospora mating-type genes into mat- and mat+ strains of the closely related heterothallic fungus P. anserina. The transformation experiments show that mating-type genes from S. macrospora induce fruiting body formation in P. anserina. PMID:9335594

  14. 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...

  15. Podospora Lautarea sp. nov. from Southern Alps (France): description and physiological properties.

    PubMed

    Guiraud, P; Sage, L; Seigle-Murandi, F; Steiman, R

    1994-01-01

    A taxonomic description of Podospora Lautarea sp. nov. is provided. This species is characterized by a reddish brown peridium, and by its large, asymmetric ascospores, small, hyaline, unique primary appendage, absence of secondary appendage and cylindrical asci. Due to the size of its appendage, this species may be related to Podospora minicaudaFaureal et Locquin-Linard. Asci and ascospores are close to those of P. fimbriata (Bayer) Cain, but the dimensions and ornamentation of perithecia are quite different. To summarize, this species belongs to the small group of Podospora exhibiting only one appendage (such as P. minicauda, P. carpinicola Mouchacca or P. horridula (Sacc.) Francis and Sparrow) but can not be assimilated to one of the described species in this group. The main cultural characteristics and physiological properties of this species are described. PMID:7710284

  16. 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...

  17. 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

  18. A NEW SPECIES OF ASCOMYCETES FROM MEXICO

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During a survey of tropical Ascomycetes from Mexico, an interesting fungus was isolated from sandy beach soil collected from the Gulf of Mexico seacoast. The fungus produces a rudimentary ascoma with oblate, smooth-walled, unornamented, greenish ascospores and lacks a distinctive peridium surroundi...

  19. Introduction The ascomycete Hypocrea jecorina (anamorph

    E-print Network

    Qin, Wensheng

    Introduction The ascomycete Hypocrea jecorina (anamorph Trichoderma reesei) is one of the most of different carbon sources on cellulase production by Hypocrea jecorina (Trichoderma reesei) strains Mehdi in RUT- C30 with ability to grow on microcrystalline cellulose. Keywords: Trichoderma reesei, cellulase

  20. Prevalence of transcription factors in ascomycete and basidiomycete fungi

    PubMed Central

    2014-01-01

    Background Gene regulation underlies fungal physiology and therefore is a major factor in fungal biodiversity. Analysis of genome sequences has revealed a large number of putative transcription factors in most fungal genomes. The presence of fungal orthologs for individual regulators has been analysed and appears to be highly variable with some regulators widely conserved and others showing narrow distribution. Although genome-scale transcription factor surveys have been performed before, no global study into the prevalence of specific regulators across the fungal kingdom has been presented. Results In this study we have analysed the number of members for 37 regulator classes in 77 ascomycete and 31 basidiomycete fungal genomes and revealed significant differences between ascomycetes and basidiomycetes. In addition, we determined the presence of 64 regulators characterised in ascomycetes across these 108 genomes. This demonstrated that overall the highest presence of orthologs is in the filamentous ascomycetes. A significant number of regulators lacked orthologs in the ascomycete yeasts and the basidiomycetes. Conversely, of seven basidiomycete regulators included in the study, only one had orthologs in ascomycetes. Conclusions This study demonstrates a significant difference in the regulatory repertoire of ascomycete and basidiomycete fungi, at the level of both regulator class and individual regulator. This suggests that the current regulatory systems of these fungi have been mainly developed after the two phyla diverged. Most regulators detected in both phyla are involved in central functions of fungal physiology and therefore were likely already present in the ancestor of the two phyla. PMID:24650355

  1. 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.

  2. 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...

  3. 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 (...

  4. ASCOMYCETOUS MITOSIS IN BASIDIOMYCETOUS YEASTS: ITS EVOLUTIONARY IMPLICATIONS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In budding cells of ascomycetous yeasts, mitosis occurs in the parent, while in basidiomyceteous yeasts it occurs in the bud. However, in the basidiomycete Agaricostilbum pulcherrimum mitosis occurs in the parent and parent-bud junction. To test whether A. pulcherrimum has a novel mitotic pattern, i...

  5. Relative incidence of ascomycetous yeasts in arctic coastal environments.

    PubMed

    Butinar, Lorena; Strmole, Tadeja; Gunde-Cimerman, Nina

    2011-05-01

    Previous studies of fungi in polar environments have revealed a prevalence of basidiomycetous yeasts in soil and in subglacial environments of polythermal glaciers. Ascomycetous yeasts have rarely been reported from extremely cold natural environments, even though they are known contaminants of frozen foods. Using media with low water activity, we have isolated various yeast species from the subglacial ice of four glaciers from the coastal Arctic environment of Kongsfjorden, Spitzbergen, including Debaryomyces hansenii and Pichia guillermondii, with counts reaching 10(4) CFU L(-1). Together with the basidiomycetes Cryptococcus liquefaciens and Rhodotorula mucilaginosa, these yeasts represent the stable core of the subglacial yeast communities. Other glacial ascomycetous species isolated included Candida parapsilosis and a putative new species that resembles Candida pseudorugosa. The archiascomycete Protomyces inouyei has seldom been detected anywhere in the world but was here recovered from ice in a glacier cave. The glacier meltwater contained only D. hansenii, whereas the seawater contained D. hansenii, Debaryomyces maramus, Pichia guilliermondii, what appears to represent a novel species resembling Candida galli and Metschnikowia bicuspidata. Only P. guilliermondii was isolated from sea ice, while snow/ice in the fjord tidal zone included C. parapsilosis, D. hansenii, P. guilliermondii and Metschnikowia zobellii. All of these isolated strains were characterized as psychrotolerant and xero/halotolerant, with the exception of P. inouyei. PMID:21221569

  6. 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

  7. Assessing conserved function of conidiation regulators in two distantly related ascomycetes, Aspergillus nidulans and Neurospora crassa 

    E-print Network

    Chung, Da Woon

    2012-07-16

    Conidiation is a common and critical asexual reproductive mode in fungi. The ascomycetes, the largest group in the kingdom Fungi undergo conidiation. The wide array of morphological difference in a conidiophore and conidial ...

  8. Ascomycete fungal communities associated with early decaying leaves of Spartina spp. from central California estuaries.

    PubMed

    Lyons, Justine I; Alber, Merryl; Hollibaugh, James T

    2010-02-01

    Ascomycetous fungi play an important role in the early stages of decomposition of Spartina alterniflora, but their role in the decomposition of other Spartina species has not been investigated. Here we use fingerprint (terminal restriction fragment length polymorphism) and phylogenetic analyses of the 18S to 28S internal transcribed spacer region to compare the composition of the ascomycete fungal communities on early decay blades of Spartina species (Spartina alterniflora, Spartina densiflora, Spartina foliosa, and a hybrid (S. alterniflora x S. foliosa)) collected from three salt marshes in San Francisco Bay and one in Tomales Bay, California, USA. Phaeosphaeria spartinicola was found on all samples collected and was often dominant. Two other ascomycetes, Phaeosphaeria halima and Mycosphaerella sp. strain 2, were also common. These three species are the same ascomycetes previously identified as the dominant fungal decomposers on S. alterniflora on the east coast. Ascomycetes appeared to exhibit varying degrees of host specificity, demonstrated by grouping patterns on phylogenetic trees. Neither the exotic S. alterniflora nor the hybrid supported fungal flora different from that of the native S. foliosa. However, S. densiflora had a significantly different fungal community than the other species, and hosted at least two unique ascomycetes. Significant differences in the fungal decomposer communities were also detected within species (two clones of S. foliosa), but these were minor and may be due to morphological differences among the plants. PMID:19777266

  9. Biotechnology of non-Saccharomyces yeasts--the ascomycetes.

    PubMed

    Johnson, Eric A

    2013-01-01

    Saccharomyces cerevisiae and several other yeast species are among the most important groups of biotechnological organisms. S. cerevisiae and closely related ascomycetous yeasts are the major producer of biotechnology products worldwide, exceeding other groups of industrial microorganisms in productivity and economic revenues. Traditional industrial attributes of the S. cerevisiae group include their primary roles in food fermentations such as beers, cider, wines, sake, distilled spirits, bakery products, cheese, sausages, and other fermented foods. Other long-standing industrial processes involving S. cerevisae yeasts are production of fuel ethanol, single-cell protein (SCP), feeds and fodder, industrial enzymes, and small molecular weight metabolites. More recently, non-Saccharomyces yeasts (non-conventional yeasts) have been utilized as industrial organisms for a variety of biotechnological roles. Non-Saccharomyces yeasts are increasingly being used as hosts for expression of proteins, biocatalysts and multi-enzyme pathways for the synthesis of fine chemicals and small molecular weight compounds of medicinal and nutritional importance. Non-Saccharomyces yeasts also have important roles in agriculture as agents of biocontrol, bioremediation, and as indicators of environmental quality. Several of these products and processes have reached commercial utility, while others are in advanced development. The objective of this mini-review is to describe processes currently used by industry and those in developmental stages and close to commercialization primarily from non-Saccharomyces yeasts with an emphasis on new opportunities. The utility of S. cerevisiae in heterologous production of selected products is also described. PMID:23184219

  10. 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

  11. Molecular systematics of the dimorphic ascomycete genus Taphrina.

    PubMed

    Rodrigues, Manuel G; Fonseca, Alvaro

    2003-03-01

    The ascomycete genus Taphrina Fries comprises nearly 100 species recognized by their mycelial states when parasitic on different vascular plants. Whereas the filamentous state is strictly phytoparasitic, the yeast state is saprobic and can be cultured on artificial media. Taphrina species are differentiated mainly on the basis of host range and geographical distribution, type and site of infection and morphology of the sexual stage in infected tissue. However, there has been little progress in the systematics of the genus in recent years, mainly because of the scarcity of molecular studies and available cultures. The main aim of the present study was the reappraisal of species boundaries in Taphrina based on the genetic characterization of cultures (yeast states) that represent about one-third of the currently recognized species. The molecular methods used were (i) PCR fingerprinting using single primers for microsatellite regions and (ii) determination of nucleotide sequences of two approx. 600 bp nuclear rDNA regions, the 5' end of the 26S rRNA gene (D1/D2 domains) and the internal transcribed spacer region (which includes the 5.8S rRNA gene). Sequencing results confirmed the monophyly of the genus (with the probable exclusion of Taphrina vestergrenii) and the combined analysis of the two methods corroborated, in most cases, separation of species defined on the basis of conventional criteria. However, genetic heterogeneity was found within some species and conspecificity was suggested for strains that have been deemed to represent distinct species. Sequences from the ITS region displayed a higher degree of divergence than those of the D1/D2 region between closely related species, but were relatively conserved within species (> 99% identity) and were thus more useful for the effective differentiation of Taphrina species. The results further allowed other topics to be addressed such as the correlation between the molecular phylogenetic clustering of certain species and the respective host plant family and the significance of molecular methods in the accurate diagnosis of the different diseases caused by Taphrina species. PMID:12710634

  12. Control of Herpomyces spp. (Ascomycetes: Laboulbeniales) infection in the wood cockroach, Parcoblatta lata (Dictyoptera

    E-print Network

    Note Control of Herpomyces spp. (Ascomycetes: Laboulbeniales) infection in the wood cockroach on cockroaches (Guthrie and Tindall, 1968; Richards and Smith, 1956; Roth and Willis, 1960). The haustoria of Herpomyces penetrate the cuticle of the cockroach, entering the underlying cells and causing a dermatitis

  13. Mate-recognition and species boundaries in the ascomycetes Simon H. Martin & Emma T. Steenkamp &

    E-print Network

    , and two pheromone/receptor pairs control sexual attraction. However, ascomycete reproductive genes can-recognition in this group are relatively simple: a "mating type" locus determines reproductive mode and sexual compatibility, we examine the mechanisms of sexual interaction in ascomy- cetes and explore current evidence

  14. Soil Ecology of the Entomopathogenic Ascomycetes: A Critical Examination of What We (Think) We Know

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter provides an in-depth review of what is and is not known about the soil ecology of the entomopathogenic Ascomycetes, particularly the fungi Beauveria bassiana and Metarhizium anisopliae. The efficacy of entomopathogenic fungi in soil is subject to a matrix of interlocking abiotic and bi...

  15. 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 ...

  16. Phylogenomic analysis of type I polyketide synthase genes in pathogenic and saprobic ascomycetes

    E-print Network

    Phylogenomic analysis of type I polyketide synthase genes in pathogenic and saprobic ascomycetes for some plant pathogens and pigments such as melanin. In this study, a phylogenomic approach was used to investigate the origin and diversity of fungal genes encoding putative PKSs that are predicted to synthesize

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

    PubMed

    Tedersoo, Leho; Pärtel, Kadri; Jairus, Teele; Gates, Genevieve; Pőldmaa, 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

  18. Mitochondrial RNase P RNAs in ascomycete fungi: Lineage-specific variations in RNA secondary structure

    PubMed Central

    SEIF, ELIAS R.; FORGET, LISE; MARTIN, NANCY C.; LANG, B. FRANZ

    2003-01-01

    The RNA subunit of mitochondrial RNase P (mtP-RNA) is encoded by a mitochondrial gene (rnpB) in several ascomycete fungi and in the protists Reclinomonas americana and Nephroselmis olivacea. By searching for universally conserved structural elements, we have identified previously unknown rnpB genes in the mitochondrial DNAs (mtDNAs) of two fission yeasts, Schizosaccharomyces pombe and Schizosaccharomyces octosporus; in the budding yeast Pichia canadensis; and in the archiascomycete Taphrina deformans. The expression of mtP-RNAs of the predicted size was experimentally confirmed in the two fission yeasts, and their precise 5? and 3? ends were determined by sequencing of cDNAs generated from circularized mtP-RNAs. Comparative RNA secondary structure modeling shows that in contrast to mtP-RNAs of the two protists R. americana and N. olivacea, those of ascomycete fungi all have highly reduced secondary structures. In certain budding yeasts, such as Saccharomycopsis fibuligera, we find only the two most conserved pairings, P1 and P4. A P18 pairing is conserved in Saccharomyces cerevisiae and its close relatives, whereas nearly half of the minimum bacterial consensus structure is retained in the RNAs of fission yeasts, Aspergillus nidulans and Taphrina deformans. The evolutionary implications of the reduction of mtP-RNA structures in ascomycetes will be discussed. PMID:12923256

  19. Mitochondrial RNase P RNAs in ascomycete fungi: lineage-specific variations in RNA secondary structure.

    PubMed

    Seif, Elias R; Forget, Lise; Martin, Nancy C; Lang, B Franz

    2003-09-01

    The RNA subunit of mitochondrial RNase P (mtP-RNA) is encoded by a mitochondrial gene (rnpB) in several ascomycete fungi and in the protists Reclinomonas americana and Nephroselmis olivacea. By searching for universally conserved structural elements, we have identified previously unknown rnpB genes in the mitochondrial DNAs (mtDNAs) of two fission yeasts, Schizosaccharomyces pombe and Schizosaccharomyces octosporus; in the budding yeast Pichia canadensis; and in the archiascomycete Taphrina deformans. The expression of mtP-RNAs of the predicted size was experimentally confirmed in the two fission yeasts, and their precise 5' and 3' ends were determined by sequencing of cDNAs generated from circularized mtP-RNAs. Comparative RNA secondary structure modeling shows that in contrast to mtP-RNAs of the two protists R. americana and N. olivacea, those of ascomycete fungi all have highly reduced secondary structures. In certain budding yeasts, such as Saccharomycopsis fibuligera, we find only the two most conserved pairings, P1 and P4. A P18 pairing is conserved in Saccharomyces cerevisiae and its close relatives, whereas nearly half of the minimum bacterial consensus structure is retained in the RNAs of fission yeasts, Aspergillus nidulans and Taphrina deformans. The evolutionary implications of the reduction of mtP-RNA structures in ascomycetes will be discussed. PMID:12923256

  20. Expression and Function of Sex Pheromones and Receptors in the Homothallic Ascomycete Gibberella zeae?

    PubMed Central

    Lee, Jungkwan; Leslie, John F.; Bowden, Robert L.

    2008-01-01

    In heterothallic ascomycete fungi, idiomorphic alleles at the MAT locus control two sex pheromone-receptor pairs that function in the recognition and chemoattraction of strains with opposite mating types. In the ascomycete Gibberella zeae, the MAT locus is rearranged such that both alleles are adjacent on the same chromosome. Strains of G. zeae are self-fertile but can outcross facultatively. Our objective was to determine if pheromones retain a role in sexual reproduction in this homothallic fungus. Putative pheromone precursor genes (ppg1 and ppg2) and their corresponding pheromone receptor genes (pre2 and pre1) were identified in the genomic sequence of G. zeae by sequence similarity and microsynteny with other ascomycetes. ppg1, a homolog of the Saccharomyces ?-factor pheromone precursor gene, was expressed in germinating conidia and mature ascospores. Expression of ppg2, a homolog of the a-factor pheromone precursor gene, was not detected in any cells. pre2 was expressed in all cells, but pre1 was expressed weakly and only in mature ascospores. ppg1 or pre2 deletion mutations reduced fertility in self-fertilization tests by approximately 50%. ?ppg1 reduced male fertility and ?pre2 reduced female fertility in outcrossing tests. In contrast, ?ppg2 and ?pre1 had no discernible effects on sexual function. ?ppg1/?ppg2 and ?pre1/?pre2 double mutants had the same phenotype as the ?ppg1 and ?pre2 single mutants. Thus, one of the putative pheromone-receptor pairs (ppg1/pre2) enhances, but is not essential for, selfing and outcrossing in G. zeae whereas no functional role was found for the other pair (ppg2/pre1). PMID:18503004

  1. 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-Toli?, 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.

  2. Systematics of the ascomycetous yeasts assessed from ribosomal RNA sequence divergence.

    PubMed

    Kurtzman, C P

    1993-02-01

    Extent of divergence in partial nucleotide sequences from large and small subunit ribosomal RNAs was used to estimate genetic relationships among ascomycetous yeasts and yeastlike fungi. The comparisons showed four phylogenetically distinct groups comprised of the following taxa: Group 1. The budding yeasts Saccharomyces, Saccharomycopsis, Debaryomyces, Metschnikowia, Saturnospora, and Lipomyces, and the yeastlike genera Ascoidea, Cephaloascus, Dipodascus, Dipodascopsis, and Galactomyces; Group 2. Eremascus, Emericella and Ceratocystis; Group 3. Taphrina and Protomyces; Group 4. Schizosaccharomyces. Because of the genetic relationships indicated by sequence analysis, Group 1 taxa are retained in the order Endomycetales, and Schizosaccharomyces is retained in the Schizosaccharomycetales Prillinger et al. ex Kurtzman. PMID:8259833

  3. 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.

  4. The filamentous ascomycete Sordaria macrospora can survive in ambient air without carbonic anhydrases.

    PubMed

    Lehneck, Ronny; Elleuche, Skander; Pöggeler, Stefanie

    2014-06-01

    The rapid interconversion of carbon dioxide and bicarbonate (hydrogen carbonate) is catalysed by metalloenzymes termed carbonic anhydrases (CAs). CAs have been identified in all three domains of life and can be divided into five evolutionarily unrelated classes (?, ?, ?, ? and??) that do not share significant sequence similarities. The function of the mammalian, prokaryotic and plant ?-CAs has been intensively studied but the function of CAs in filamentous ascomycetes is mostly unknown. The filamentous ascomycete Sordaria macrospora codes for four CAs, three of the ?-class and one of the ?-class. Here, we present a functional analysis of CAS4, the S. macrospora ?-class CA. The CAS4 protein was post-translationally glycosylated and secreted. The knockout strain ?cas4 had a significantly reduced rate of ascospore germination. To determine the cas genes required for S.?macrospora growth under ambient air conditions, we constructed double and triple mutations of the four cas genes in all possible combinations and a quadruple mutant. Vegetative growth rate of the quadruple mutant lacking all cas genes was drastically reduced compared to the wild type and invaded the agar under normal air conditions. Likewise the fruiting bodies were embedded in the agar and completely devoid of mature ascospores. PMID:24720701

  5. Body plan evolution of ascomycetes, as inferred from an RNA polymerase II phylogeny

    PubMed Central

    Liu, Yajuan J.; Hall, Benjamin D.

    2004-01-01

    The mode of evolution of the biologically diverse forms of ascomycetes is not well understood, largely because the descent relationships remain unresolved. By using sequences of the nuclear gene RPB2, we have inferred with considerable resolution the phylogenetic relationships between major groups within the phylum Ascomycota. These relationships allow us to deduce a historical pattern of body plan evolution. Within Taphrinomycotina, the most basal group, two simple body plans exist: uncovered asci with unicellular growth, or rudimentary ascoma with hyphal growth. Ancestral ascomycetes were filamentous; hyphal growth was lost independently in the yeast forms of Taphrinomycotina and Saccharomycotina. Pezizomycotina, the sister group to Saccharomycotina, retained mycelial growth while elaborating two basic ontogenetic pathways for ascoma formation and centrum development. The RPB2 phylogeny shows with significant statistical support that taxa in Pezizomycotina with ascohymenial ontogeny (ascoma generally forms after nuclear pairing) are ancestral and paraphyletic, whereas ascolocular fungi with fissitunicate asci are a clade derived from them. Ascolocular lichens are polyphyletic, whereas ascohymenial lichens comprise a monophyletic group that includes the Lecanorales. Our data are not consistent with a derived origin of Eurotiomycetes including Aspergillus and Trichophyton from within a lichen-forming ancestral group. For these reasons, the results of this study are considerably at variance with the conclusion that major fungal lineages are derived from lichensymbiotic ancestors. Interpretation of our results in the context of early work suggests that ascoma ontogeny and centrum characters are not in conflict with the molecular data. PMID:15070748

  6. Functional Analysis of Developmentally Regulated Genes chs7 and sec22 in the Ascomycete Sordaria macrospora.

    PubMed

    Traeger, Stefanie; Nowrousian, Minou

    2015-06-01

    During sexual development, filamentous ascomycetes form complex, three-dimensional fruiting bodies for the generation and dispersal of spores. In previous studies, we identified genes with evolutionary conserved expression patterns during fruiting body formation in several fungal species. Here, we present the functional analysis of two developmentally up-regulated genes, chs7 and sec22, in the ascomycete Sordaria macrospora. The genes encode a class VII (division III) chitin synthase and a soluble N-ethylmaleimide-sensitive-factor attachment protein receptor (SNARE) protein, respectively. Deletion mutants of chs7 had normal vegetative growth and were fully fertile but showed sensitivity toward cell wall stress. Deletion of sec22 resulted in a reduced number of ascospores and in defects in ascospore pigmentation and germination, whereas vegetative growth was normal in the mutant. A SEC22-EGFP fusion construct under control of the native sec22 promoter and terminator regions was expressed during different stages of sexual development. Expression of several development-related genes was deregulated in the sec22 mutant, including three genes involved in melanin biosynthesis. Our data indicate that chs7 is dispensable for fruiting body formation in S. macrospora, whereas sec22 is required for ascospore maturation and germination and thus involved in late stages of sexual development. PMID:25873638

  7. 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 ...

  8. 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

  9. Vegetative incompatibility in the ascomycete Rosellinia necatrix studied by fluorescence microscopy.

    PubMed

    Aimi, Tadanori; Yotsutani, Yoshiki; Morinaga, Tsutomu

    2002-01-01

    We describe our examination of the cytological characteristics of the vegetative incompatibility reaction in a filamentous ascomycetes, Rosellinia necatrix, by analyzing the fluorescence emitted by ethidium bromide and acridine orange stained nuclei. Hyphal anastomosis between incompatible strains, which were field and single ascospore isolates, were observed with cell death showing fused hyphae, and nuclei debris which were intensified by staining with ethidium bromide. In contrast, the nuclei in a living cell were not intensified by staining with ethidium bromide but were intensified by staining with acridine orange. A strain was found which did not form a barrier reaction, but which could be shown to undergo cell death and therefore showed a positive vegetative incompatibility reaction. We also examined the vegetative incompatibility among five single ascospore isolates and the putative parent strain from the same perithecium; all strains were incompatible. These results strongly suggest that vegetative incompatibility in R. necatrix is regulated by many loci. PMID:12111741

  10. 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

  11. 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

  12. The evolutionary history of Cytochrome P450 genes in four filamentous Ascomycetes

    PubMed Central

    Deng, Jixin; Carbone, Ignazio; Dean, Ralph A

    2007-01-01

    Background The Cytochrome P450 system is important in fungal evolution for adapting to novel ecological niches. To elucidate the evolutionary process of cytochrome P450 genes in fungi with different life styles, we studied the patterns of gene gains and losses in the genomes of four filamentous Ascomycetes, including two saprotrophs (Aspergillus nidulans (AN) and Neurospora crassa (NC)) and two plant pathogens (Fusarium graminearum (FG) and Magnaporthe grisea (MG)). Results A total of 376 P450 genes were assigned to 168 families according to standard nomenclature. On average, only 1 to 2 genes per family were in each genome. To resolve conflicting results between different clustering analyses and standard family designation, a higher order relationship was formulated. 376 genes were clustered into 115 clans. Subsequently a novel approach based on parsimony was developed to build the evolutionary models. Based on these analyses, a core of 30 distinct clans of P450s was defined. The core clans experienced contraction in all four fungal lineages while new clans expanded in all with exception of NC. MG experienced more genes and clans gains compared to the other fungi. Parsimonious analyses unanimously supported one species topology for the four fungi. Conclusion The four studied fungi exhibit unprecedented diversity in their P450omes in terms of coding sequence, intron-exon structures and genome locations, suggesting a complicated evolutionary history of P450s in filamentous Ascomycetes. Clan classification and a novel strategy were developed to study evolutionary history. Contraction of core clans and expansion of novel clans were identified. The exception was the NC lineage, which exhibited pure P450 gene loss. PMID:17324274

  13. 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

  14. Specific, non-nutritional association between an ascomycete fungus and Allomerus plant-ants

    PubMed Central

    Ruiz-González, Mario X.; Malé, Pierre-Jean G.; Leroy, Céline; Dejean, Alain; Gryta, Hervé; Jargeat, Patricia; Quilichini, Angélique; Orivel, Jérôme

    2011-01-01

    Ant–fungus associations are well known from attine ants, whose nutrition is based on a symbiosis with basidiomycete fungi. Otherwise, only a few non-nutritional ant–fungus associations have been recorded to date. Here we focus on one of these associations involving Allomerus plant-ants that build galleried structures on their myrmecophytic hosts in order to ambush prey. We show that this association is not opportunistic because the ants select from a monophyletic group of closely related fungal haplotypes of an ascomycete species from the order Chaetothyriales that consistently grows on and has been isolated from the galleries. Both the ants' behaviour and an analysis of the genetic population structure of the ants and the fungus argue for host specificity in this interaction. The ants' behaviour reveals a major investment in manipulating, growing and cleaning the fungus. A molecular analysis of the fungus demonstrates the widespread occurrence of one haplotype and many other haplotypes with a lower occurrence, as well as significant variation in the presence of these fungal haplotypes between areas and ant species. Altogether, these results suggest that such an interaction might represent an as-yet undescribed type of specific association between ants and fungus in which the ants cultivate fungal mycelia to strengthen their hunting galleries. PMID:21084334

  15. 1 Reactive oxygen species target specific tryptophan site in the 2 mitochondrial ATP synthase

    E-print Network

    Roegner, Matthias

    Keywords: 20 ATP synthase 21 Oxidative stress 22 Podospora anserina 23 Aging 24 Posttranslational be involved in the metabolic per- 34ception of oxidative stress or regulation of enzyme activity. A putative a Plant Biochemistry, Faculty of Biology & Biotechnology, Ruhr University Bochum, D-44780 Bochum, Germany

  16. 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 ?M 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

  17. Mn(II) Oxidation by an Ascomycete Fungus is Linked to Superoxide Production During Asexual Reproduction

    SciTech Connect

    Hansel, Colleen M.; Zeiner, Carolyn A.; Santelli, Cara M.; Webb, Samuel 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-speci?c chemical assays, microspectroscopy, and electron microscopy to show that a common Ascomycete ?lamentous 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 identi?cation 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.

  18. 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

  19. NMR analysis of the binding mode of two fungal endo-?-1,4-mannanases from GH5 and GH26 families.

    PubMed

    Marchetti, Roberta; Berrin, Jean-Guy; Couturier, Marie; Ul Qader, Shah Ali; Molinaro, Antonio; Silipo, Alba

    2015-12-15

    The enzymatic digestion of the main components of lignocellulosic biomass, including plant cell wall mannans, constitutes a fundamental step in the renewable biofuel production, with great potential benefit in the industrial field. Despite several reports of X-ray structures of glycoside hydrolases, how polysaccharides are specifically recognized and accommodated in the enzymes binding site still remains a pivotal matter of research. Within this frame, NMR spectroscopic techniques provide key binding information, complementing and/or enhancing the structural view by X-ray crystallography. Here we provide deep insights into the binding mode of two endo-?-1,4 mannanases from the coprophilous ascomycete Podospora anserina, PaMan26A and PaMan5A, involved in the hydrolysis of plant cell wall mannans and heteromannans. The investigation at a molecular level of the interaction between the wild-type enzymes and inactive mutants with manno-oligosaccharides, revealed a different mode of action among the two glycoside hydrolases most likely due to the presence of the additional and peculiar -4 subsite in the PaMan26A binding pocket. PMID:26567779

  20. 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...

  1. RAPID IDENTFICATION OF ASCOMYCETOUS YEASTS FROM CLINICAL SPECIMENS BY A MOLECULAR-BASED FLOW CYTOMETRY METHOD AND COMPARISION WITH IDENTIFICATIONS FROM PHENOTYPIC ASSAYS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was designed to compare the identification of ascomycetous yeasts recovered from clinical specimens by using phenotypic assays (PA) and a molecular flow cytometric (FC) method. LSU rRNA D1/D2 gene sequence analysis was also performed and served as the reference for correct strain identif...

  2. 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 Ĺ 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 Ĺ 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.

  3. 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 (Stĺl), 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

  4. 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

  5. Phylogenetic analysis identifies the 'megabacterium' of birds as a novel anamorphic ascomycetous yeast, Macrorhabdus ornithogaster gen. nov., sp. nov.

    PubMed

    Tomaszewski, Elizabeth K; Logan, Kathleen S; Snowden, Karen F; Kurtzman, Cletus P; Phalen, David N

    2003-07-01

    An organism commonly referred to as 'megabacterium' colonizes the gastric isthmus of many species of birds. It is weakly gram-positive and periodic acid-Schiff-positive and stains with silver stains. Previous studies have shown that it has a nucleus and a cell wall similar to those seen in fungi. Calcofluor white M2R staining suggests that the cell wall contains chitin, a eukaryote-specific substance, and rRNA in situ hybridization demonstrates that it is a eukaryote. To characterize this organism phylogenetically, DNA was extracted from purified cells. rDNA was readily amplified by PCR with pan-fungal DNA primer sets and primer sets derived from the newly determined sequence, but not with bacteria-specific primer sets. Specific primer sets amplified rDNA from isthmus scrapings from an infected bird, but not from a non-infected bird or other control DNA. The sequence was confirmed to derive from the purified organism by in situ rRNA hybridization using a specific probe. Phylogenetic analysis of sequences of the 18S rDNA and domain D1/D2 of 26S rDNA showed the organism to be a previously undescribed anamorphic ascomycetous yeast representing a new genus. The name Macrorhabdus ornithogaster gen. nov., sp. nov. is proposed for this organism. The type material is CBS 9251T (= NRRL Y-27487T). PMID:12892150

  6. Mutations to LmIFRD affect cell wall integrity, development and pathogenicity of the ascomycete Leptosphaeria maculans.

    PubMed

    Van de Wouw, Angela P; Pettolino, Filomena A; Howlett, Barbara J; Elliott, Candace E

    2009-09-01

    Maintaining cell wall integrity is essential for fungal growth and development. We describe two mutants with altered expression of a gene, LmIFRD, from the ascomycete Leptosphaeria maculans. Truncation of the LmIFRD transcript in a T-DNA insertional mutant led to slower germination, less sporulation and loss-of-pathogenicity towards Brassica napus, whereas silencing of the LmIFRD transcript led to increased germination, sporulation and earlier infection. The increased tolerance to cell wall lysing enzymes and cell wall-disrupting compounds of the T-DNA mutant contrasts with decreased tolerance of the silenced mutant and suggests altered cell wall integrity and accessibility to 1,3-linked glucan and chitin. Lectin binding experiments and monosaccharide analysis revealed altered polysaccharide content and structure within the cell wall of the LmIFRD mutants, notably increased 1,3-linked galactose and chitin within the cell wall of the T-DNA mutant. This is the first analysis of monosaccharide linkage composition of cell walls of spores and mycelia for any dothideomycete. PMID:19539773

  7. 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

  8. 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?Ĺ 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

  9. Large-Scale Introgression Shapes the Evolution of the Mating-Type Chromosomes of the Filamentous Ascomycete Neurospora tetrasperma

    PubMed Central

    Menkis, Audrius; Whittle, Carrie A.; Andersson, Siv G. E.; Johannesson, Hanna

    2012-01-01

    The significance of introgression as an evolutionary force shaping natural populations is well established, especially in animal and plant systems. However, the abundance and size of introgression tracts, and to what degree interspecific gene flow is the result of adaptive processes, are largely unknown. In this study, we present medium coverage genomic data from species of the filamentous ascomycete Neurospora, and we use comparative genomics to investigate the introgression landscape at the genomic level in this model genus. We revealed one large introgression tract in each of the three investigated phylogenetic lineages of Neurospora tetrasperma (sizes of 5.6 Mbp, 5.2 Mbp, and 4.1 Mbp, respectively). The tract is located on the chromosome containing the locus conferring sexual identity, the mating-type (mat) chromosome. The region of introgression is confined to the region of suppressed recombination and is found on one of the two mat chromosomes (mat a). We used Bayesian concordance analyses to exclude incomplete lineage sorting as the cause for the observed pattern, and multilocus genealogies from additional species of Neurospora show that the introgression likely originates from two closely related, freely recombining, heterothallic species (N. hispaniola and N. crassa/N. perkinsii). Finally, we investigated patterns of molecular evolution of the mat chromosome in Neurospora, and we show that introgression is correlated with reduced level of molecular degeneration, consistent with a shorter time of recombination suppression. The chromosome specific (mat) and allele specific (mat a) introgression reported herein comprise the largest introgression tracts reported to date from natural populations. Furthermore, our data contradicts theoretical predictions that introgression should be less likely on sex-determining chromosomes. Taken together, the data presented herein advance our general understanding of introgression as a force shaping eukaryotic genomes. PMID:22844246

  10. 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

  11. 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 that the genus Trichoderma/Hypocrea has a proliferated arsenal of class II hydrophobins which arose by purifying selection and birth-and-death evolution.

  12. A Fox2-Dependent Fatty Acid ß-Oxidation Pathway Coexists Both in Peroxisomes and Mitochondria of the Ascomycete Yeast Candida lusitaniae

    PubMed Central

    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 14C?-palmitoyl-CoA consumption, we demonstrated that fatty acid catabolism takes place in both peroxisomal and mitochondrial subcellular fractions. We then observed that a fox2? 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 ?-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

  13. Crystal structure of the GalNAc/Gal-specific agglutinin from the phytopathogenic ascomycete Sclerotinia sclerotiorum reveals novel adaptation of a ?-trefoil domain

    PubMed Central

    Sulzenbacher, Gerlind; Roig-Zamboni, Véronique; Peumans, Willy J.; Rougé, Pierre; Van Damme, Els J.M.; Bourne, Yves

    2010-01-01

    A lectin from the phytopathogenic ascomycete Sclerotina sclerotiorum that shares only weak sequence similarity with characterized fungal lectins has recently been identified. Sclerotina sclerotiorum agglutinin (SSA) is a homodimeric protein consisting of two identical subunits of ?17 kDa and displays specificity primarily towards Gal/GalNAc. Glycan array screening indicates that SSA readily interacts with Gal/GalNAc-bearing glycan chains. The crystal structures of SSA in the ligand-free form and in complex with the Gal-?1,3-GalNAc (T-antigen) disaccharide have been determined at 1.6 and 1.97 Ĺ resolution, respectively. SSA adopts a ?-trefoil domain as previously identified for other carbohydrate-binding proteins of the ricin B-like lectin superfamily and accommodates terminal non-reducing galactosyl and N-acetylgalactosaminyl glycans. Unlike other structurally related lectins, SSA contains a single carbohydrate-binding site at site ?. SSA reveals a novel dimeric assembly markedly dissimilar to those described earlier for ricin-type lectins. The present structure exemplifies the adaptability of the ?-trefoil domain in the evolution of fungal lectins. PMID:20566411

  14. 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

  15. Minutisphaerales (Dothideomycetes, Ascomycota): a new order of freshwater ascomycetes including a new family, Minutisphaeraceae, and two new species from North Carolina, USA.

    PubMed

    Raja, Huzefa A; El-Elimat, Tamam; Oberlies, Nicholas H; Shearer, Carol A; Miller, Andrew N; Tanaka, Kazuaki; Hashimoto, Akira; Fournier, Jacques

    2015-01-01

    Minutisphaera is a recently established genus of freshwater Dothideomycetes characterized by small, globose to subglobose or apothecioid, erumpent to superficial, brown ascomata; fissitunicate, eight-spored, ovoid to obclavate asci; and 1-2-septate, clavate to broadly fusiform, hyaline to pale brown ascospores with or without a gelatinous sheath and filamentous appendages. The genus currently contains two species: M. fimbriatispora, the type species, and M. japonica. The higher-level phylogenetic relationship of Minutisphaera within the Dothideomycetes currently is unresolved. To establish the phylogenetic position of Minutisphaera within the Dothideomycetes and evaluate the phylogenetic affinities of newly collected Minutisphaera-like taxa, we sequenced three rDNA regions-18S, ITS1-5.8SITS2 (ITS) and 28S nuc rDNA, and a protein-coding gene, MCM7, for newly collected strains of Minutisphaera. Based on maximum likelihood and Bayesian analyses of a combined dataset (18S and 28S) composed of 167 taxa, a more refined dataset (28S and MCM7) comprising 52 taxa and a separate ITS dataset, and an examination of morphology, we describe and illustrate two new species of Minutisphaera. The Minutisphaera clade was strongly supported within the Dothideomycetes with likelihood and Bayesian statistics but did not share phylogenetic affinities with any existing taxonomic group within the Dothideomycetes. We therefore establish a new order, Minutisphaerales, and new family, Minutisphaeraceae, for this monophyletic clade of freshwater ascomycetes. Chemical analysis of the organic extract M. aspera (G427) resulted in isolation and characterization of five known secondary metabolites, of which four were dipeptides (1-4) and one an aromatic polyketide (5). Conversely, two aromatic polyketides (5, 6) were isolated and identified from the organic extract of M. parafimbriatispora (G156-4). The isolated compounds were tested for their antimicrobial activity against an array of bacteria and fungi. Compound 6 showed promising activity against Staphylococcus aureus and Mycobacterium smegmatis with minimal inhibitory concentration values of 30 and 60 ?g/mL, respectively. PMID:26315030

  16. Role of Hsp104 in the Propagation and Inheritance of the [Het-s] Prion

    PubMed Central

    Malato, Laurent; Dos Reis, Suzana; Benkemoun, Laura; Sabaté, Raimon

    2007-01-01

    The chaperones of the ClpB/HSP100 family play a central role in thermotolerance in bacteria, plants, and fungi by ensuring solubilization of heat-induced protein aggregates. In addition in yeast, Hsp104 was found to be required for prion propagation. Herein, we analyze the role of Podospora anserina Hsp104 (PaHsp104) in the formation and propagation of the [Het-s] prion. We show that ?PaHsp104 strains propagate [Het-s], making [Het-s] the first native fungal prion to be propagated in the absence of Hsp104. Nevertheless, we found that [Het-s]-propagon numbers, propagation rate, and spontaneous emergence are reduced in a ?PaHsp104 background. In addition, inactivation of PaHsp104 leads to severe meiotic instability of [Het-s] and abolishes its meiotic drive activity. Finally, we show that ?PaHSP104 strains are less susceptible than wild type to infection by exogenous recombinant HET-s(218–289) prion amyloids. Like [URE3] and [PIN+] in yeast but unlike [PSI+], [Het-s] is not cured by constitutive PaHsp104 overexpression. The observed effects of PaHsp104 inactivation are consistent with the described role of Hsp104 in prion aggregate shearing in yeast. However, Hsp104-dependency appears less stringent in P. anserina than in yeast; presumably because in Podospora prion propagation occurs in a syncitium. PMID:17881723

  17. Description of Taphrina antarctica f.a. sp. nov., a new anamorphic ascomycetous yeast species associated with Antarctic endolithic microbial communities and transfer of four Lalaria species in the genus Taphrina.

    PubMed

    Selbmann, Laura; Turchetti, Benedetta; Yurkov, Andrey; Cecchini, Clarissa; Zucconi, Laura; Isola, Daniela; Buzzini, Pietro; Onofri, Silvano

    2014-07-01

    In the framework of a large-scale rock sampling in Continental Antarctica, a number of yeasts have been isolated. Two strains that are unable to grow above 20 °C and that have low ITS sequence similarities with available data in the public domain were found. The D1/D2 LSU molecular phylogeny placed them in an isolated position in the genus Taphrina, supporting their affiliation to a not yet described species. Because the new species is able to grow in its anamorphic state only, the species Taphrina antarctica f.a. (forma asexualis) sp. nov. has been proposed to accommodate both strains (type strain DBVPG 5268(T), DSM 27485(T) and CBS 13532(T)). Lalaria and Taphrina species are dimorphic ascomycetes, where the anamorphic yeast represents the saprotrophic state and the teleomorph is the parasitic counterpart on plants. This is the first record for this genus in Antarctica; since plants are absent on the continent, we hypothesize that the fungus may have focused on the saprotrophic part of its life cycle to overcome the absence of its natural host and adapt environmental constrains. Following the new International Code of Nomenclature for Algae, Fungi and Plants (Melbourne Code 2011) the reorganization of Taphrina-Lalaria species in the teleomorphic genus Taphrina is proposed. We emend the diagnosis of the genus Taphrina to accommodate asexual saprobic states of these fungi. Taphrina antarctica was registered in MycoBank under MB 808028. PMID:24893860

  18. Molecular cloning of three genes encoding G protein alpha subunits in the white root rot fungus, Rosellinia necatrix.

    PubMed

    Aimi, T; Kano, S; Wang, Q; Morinaga, T

    2001-03-01

    Three genes encoding G protein alpha subunits were cloned from the white root rot fungus, Rosellinia necatrix, and characterized. Only one copy of each gene was present in the genome. The protein sequences of Rga1, Rga2, and Rga3 are very similar to those of MagA, MagB and MagC of Magnaporthe grisea, respectively. Moreover, Rga1 is similar to Mod-D which is closely related to vegetative incompatibility in Podospora anserina, which suggests that Rga1 is important in the vegetative incompatibility reaction in R. necatrix. Reverse transcription PCR (RT-PCR) analysis of Rga1, Rga2, and Rga3 mRNA expression showed that the three genes were all transcribed in R. necatrix cells. PMID:11330689

  19. Pathogenesis of bryophyte hosts by the ascomycete Atradidymella muscivora.

    PubMed

    Davey, Marie L; Tsuneda, Akihiko; Currah, Randolph S

    2009-07-01

    Atradidymella muscivora (Pleosporales) is a bryophyte pathogen that infects the mosses Aulacomnium palustre, Hylocomium splendens, and Polytrichum juniperinum. Light and scanning electron microscopy and extracellular enzyme production were used to characterize the interactions between this fungus and its native hosts and the model host Funaria hygrometrica. Penetration was direct via hyphae or appressoria, and hosts responded by forming layered, darkly pigmented deposits at penetration sites, similar to the papillae formed by vascular plants in response to fungal infection. Infected hosts gradually became chlorotic as hyphae grew intracellularly, presumably killing host cells. Pycnidia of the Phoma anamorph (P. muscivora) and uniloculate pseudothecia were initiated as tightly packed masses of stromatic dematiaceous hyphae within a single host cell. Mature pycnidia and pseudothecia were erumpent. A new microniche among bryophilous fungi is described, whereby A. muscivora supplants the gemmae of Aul. palustre and exploits the normal nutrient-flow of the moss gametophyte. Atradidymella muscivora produced both cellulases and soluble polyphenolic oxidases, allowing it to also function as a saprobe and degrade the cell walls of bryophytes. The saprophytic and pathogenic abilities of A. muscivora suggest it may play a role in nutrient cycling, population dynamics, and small-scale disturbances in boreal ecosystems. PMID:21628276

  20. MATHEMATICS Explosively launched spores of ascomycete fungi have

    E-print Network

    Pringle, Anne

    shape evolution. Our study uses biomechanical optimization as an orga- nizing principle for explaining have visible adaptations for minimizing drag, including the streamlined shapes of fast-swimming fish

  1. Reinforced postmating reproductive isolation barriers in Neurospora, an Ascomycete microfungus

    E-print Network

    , but natural selection against maladaptive hybridization itself can also drive evolution of reproductive as byprod- ucts of within lineage evolution as a result of natural or sexual selection or genetic drift, which is then `reinforced' by the evolution of additional barriers. Studies of reinforcement have

  2. 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 ?-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

  3. 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 ?-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 ?-stacking of the two repeats and residue-residue interactions compatible with the ?-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

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

    PubMed

    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

  5. 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

  6. 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

  7. Vegetative incompatibility in the het-6 region of Neurospora crassa is mediated by two linked genes.

    PubMed Central

    Smith, M L; Micali, O C; Hubbard, S P; Mir-Rashed, N; Jacobson, D J; Glass, N L

    2000-01-01

    Non-self-recognition during asexual growth of Neurospora crassa involves restriction of heterokaryon formation via genetic differences at 11 het loci, including mating type. The het-6 locus maps to a 250-kbp region of LGIIL. We used restriction fragment length polymorphisms in progeny with crossovers in the het-6 region and a DNA transformation assay to identify two genes in a 25-kbp region that have vegetative incompatibility activity. The predicted product of one of these genes, which we designate het-6(OR), has three regions of amino acid sequence similarity to the predicted product of the het-e vegetative incompatibility gene in Podospora anserina and to the predicted product of tol, which mediates mating-type vegetative incompatibility in N. crassa. The predicted product of the alternative het-6 allele, HET-6(PA), shares only 68% amino acid identity with HET-6(OR). The second incompatibility gene, un-24(OR), encodes the large subunit of ribonucleotide reductase, which is essential for de novo synthesis of DNA. A region in the carboxyl-terminal portion of UN-24 is associated with incompatibility and is variable between un-24(OR) and the alternative allele un-24(PA). Linkage analysis indicates that the 25-kbp un-24-het-6 region is inherited as a block, suggesting that a nonallelic interaction may occur between un-24 and het-6 and possibly other loci within this region to mediate vegetative incompatibility in the het-6 region of N. crassa. PMID:10880472

  8. 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

  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. Molecular Characterization of a New Alkaline-Tolerant Xylanase from Humicola insolens Y1

    PubMed Central

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

    2015-01-01

    An endo-1,4-?-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 Km and Vmax values for beechwood xylan were 2.2?mg?mL?1 and 462.8??mol?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

  11. 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

  12. Characterization of a Broad-Specificity ?-Glucanase Acting on ?-(1,3)-, ?-(1,4)-, and ?-(1,6)-Glucans That Defines a New Glycoside Hydrolase Family

    PubMed Central

    Lafond, Mickael; Navarro, David; Haon, Mireille; Couturier, Marie

    2012-01-01

    Here we report the cloning of the Pa_3_10940 gene from the coprophilic fungus Podospora anserina, which encodes a C-terminal family 1 carbohydrate binding module (CBM1) linked to a domain of unknown function. The function of the gene was investigated by expression of the full-length protein and a truncated derivative without the CBM1 domain in the yeast Pichia pastoris. Using a library of polysaccharides of different origins, we demonstrated that the full-length enzyme displays activity toward a broad range of ?-glucan polysaccharides, including laminarin, curdlan, pachyman, lichenan, pustulan, and cellulosic derivatives. Analysis of the products released from polysaccharides revealed that this ?-glucanase is an exo-acting enzyme on ?-(1,3)- and ?-(1,6)-linked glucan substrates and an endo-acting enzyme on ?-(1,4)-linked glucan substrates. Hydrolysis of short ?-(1,3), ?-(1,4), and ?-(1,3)/?-(1,4) gluco-oligosaccharides confirmed this striking feature and revealed that the enzyme performs in an exo-type mode on the nonreducing end of gluco-oligosaccharides. Excision of the CBM1 domain resulted in an inactive enzyme on all substrates tested. To our knowledge, this is the first report of an enzyme that displays bifunctional exo-?-(1,3)/(1,6) and endo-?-(1,4) activities toward beta-glucans and therefore cannot readily be assigned to existing Enzyme Commission groups. The amino acid sequence has high sequence identity to hypothetical proteins within the fungal taxa and thus defines a new family of glycoside hydrolases, the GH131 family. PMID:23023747

  13. Albumin impairs renal tubular tight junctions via targeting the NLRP3 inflammasome.

    PubMed

    Zhuang, Yibo; Hu, Caiyu; Ding, Guixia; Zhang, Yue; Huang, Songming; Jia, Zhanjun; Zhang, Aihua

    2015-05-01

    Proteinuria is, not only a hallmark of glomerular disease, but also a contributor to kidney injury. However, its pathogenic mechanism is still elusive. In the present study, the effects of albumin on renal tubular tight junctions and the potential molecular mechanisms of those effects were investigated. In mouse proximal tubular cells (mPTCs), albumin treatment resulted in a significant loss of the cellular tight junction proteins zonula occludens-1 (ZO-1) and claudin-1 in a time- and dose-dependent manner, indicating a severe impairment of the tight junctions. On the basis of our previous study showing that albumin stimulated NLRP3 [neuronal apoptosis inhibitor protein, major histocompatibility complex class 2 transcription activator, incompatibility locus protein from Podospora anserina, and telomerase-associated protein (NACHT); leucine-rich repeat (LRR); and pyrin domain (PYD) domains-containing protein 3] inflammasome activation in mPTCs, we pretreated mPTCs with NLRP3 siRNA (siNLRP3) and found that NLRP3 knockdown significantly blocked the downregulation of ZO-1 and claudin-1 induced by albumin. Similarly, in albumin-overloaded wild-type mice, both ZO-1 and claudin-1 were downregulated at the protein and mRNA levels in parallel with the impaired formation of the tight junctions on transmission electron microscopy and the abnormal renal tubular morphology on periodic acid-Schiff staining, which contrasted with the stimulation of NLRP3 in the renal tubules. In contrast, NLRP3 knockout (NLRP3(-/-)) mice preserved normal ZO-1 and claudin-1 expression as well as largely normal tight junctions and tubular morphology. More importantly, deletion of the NLRP3 pathway downstream component caspase-1 similarly blocked the albumin overload-induced downregulation of ZO-1 and claudin-1. Taken together, these findings demonstrated an important role of the albumin-NLRP3 inflammasome axis in mediating the impairment of renal tubular tight junctions and integrity. PMID:25715986

  14. Contribution of Specific Residues of the ?-Solenoid Fold to HET-s Prion Function, Amyloid Structure and Stability

    PubMed Central

    Schmidlin, Thierry; Chi, Celestine N.; Wasmer, Christian; Schütz, Anne; Ceschin, Johanna; Clavé, Corinne; Cescau, Sandra; Meier, Beat; Riek, Roland; Saupe, Sven J.

    2014-01-01

    The [Het-s] prion of the fungus Podospora anserina represents a good model system for studying the structure-function relationship in amyloid proteins because a high resolution solid-state NMR structure of the amyloid prion form of the HET-s prion forming domain (PFD) is available. The HET-s PFD adopts a specific ?-solenoid fold with two rungs of ?-strands delimiting a triangular hydrophobic core. A C-terminal loop folds back onto the rigid core region and forms a more dynamic semi-hydrophobic pocket extending the hydrophobic core. Herein, an alanine scanning mutagenesis of the HET-s PFD was conducted. Different structural elements identified in the prion fold such as the triangular hydrophobic core, the salt bridges, the asparagines ladders and the C-terminal loop were altered and the effect of these mutations on prion function, fibril structure and stability was assayed. Prion activity and structure were found to be very robust; only a few key mutations were able to corrupt structure and function. While some mutations strongly destabilize the fold, many substitutions in fact increase stability of the fold. This increase in structural stability did not influence prion formation propensity in vivo. However, if an Ala replacement did alter the structure of the core or did influence the shape of the denaturation curve, the corresponding variant showed a decreased prion efficacy. It is also the finding that in addition to the structural elements of the rigid core region, the aromatic residues in the C-terminal semi-hydrophobic pocket are critical for prion propagation. Mutations in the latter region either positively or negatively affected prion formation. We thus identify a region that modulates prion formation although it is not part of the rigid cross-? core, an observation that might be relevant to other amyloid models. PMID:24945274

  15. Metabolic engineering of muconic acid production in Saccharomyces cerevisiae.

    PubMed

    Curran, Kathleen A; Leavitt, John M; Karim, Ashty S; Alper, Hal S

    2013-01-01

    The dicarboxylic acid muconic acid has garnered significant interest due to its potential use as a platform chemical for the production of several valuable consumer bio-plastics including nylon-6,6 and polyurethane (via an adipic acid intermediate) and polyethylene terephthalate (PET) (via a terephthalic acid intermediate). Many process advantages (including lower pH levels) support the production of this molecule in yeast. Here, we present the first heterologous production of muconic acid in the yeast Saccharomyces cerevisiae. A three-step synthetic, composite pathway comprised of the enzymes dehydroshikimate dehydratase from Podospora anserina, protocatechuic acid decarboxylase from Enterobacter cloacae, and catechol 1,2-dioxygenase from Candida albicans was imported into yeast. Further genetic modifications guided by metabolic modeling and feedback inhibition mitigation were introduced to increase precursor availability. Specifically, the knockout of ARO3 and overexpression of a feedback-resistant mutant of aro4 reduced feedback inhibition in the shikimate pathway, and the zwf1 deletion and over-expression of TKL1 increased flux of necessary precursors into the pathway. Further balancing of the heterologous enzyme levels led to a final titer of nearly 141mg/L muconic acid in a shake-flask culture, a value nearly 24-fold higher than the initial strain. Moreover, this strain has the highest titer and second highest yield of any reported shikimate and aromatic amino acid-based molecule in yeast in a simple batch condition. This work collectively demonstrates that yeast has the potential to be a platform for the bioproduction of muconic acid and suggests an area that is ripe for future metabolic engineering efforts. PMID:23164574

  16. 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 ?M) 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 ?M. 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

  17. Molecular characterization of a partitivirus from the plant pathogenic ascomycete Rosellinia necatrix.

    PubMed

    Sasaki, A; Miyanishi, M; Ozaki, K; Onoue, M; Yoshida, K

    2005-06-01

    The W8 isolate of the phytopathogenic fungus, Rosellinia necatrix that causes white root rot, contained three segments of double-stranded (ds) RNA, namely L1, L2 and M. Purified viral particles of about 25 nm in diameter contained an RNA segment with almost the same mobility as M-dsRNA, but the band was sensitive to S1 nuclease. Molecular analysis revealed that M-dsRNA consisted of two (RNA 1 and RNA 2) similarly sized species of 2299 and 2279 bp excluding an interrupted poly (A or U) tail of 16-51 bp. The predicted largest open reading frame in RNA 1 and RNA 2 was similar to those of RNA dependent RNA polymerase (RdRp) and coat protein (CP), respectively, encoded by the family Partitiviridae. The non-coding regions (NCR) of the two segments were similar (approximately 70% base identity) at the 5' end, but different at the 3' end. The NCR at the 3' end contained adenosine-uracil rich elements (AREs) in both segments. Northern analyses revealed RNA 1 and RNA 2 in mycelial and viral particle fractions. We coined the name Rosellinia necatrix partitivirus 1-W8 (RnPV1-W8) for M-dsRNA based on viral particle morphology and sequence information. PMID:15750865

  18. A Putative Transcription Factor MYT1 Is Required for Female Fertility in the Ascomycete Gibberella zeae

    PubMed Central

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

    2011-01-01

    Gibberella zeae is an important pathogen of major cereal crops. The fungus produces ascospores that forcibly discharge from mature fruiting bodies, which serve as the primary inocula for disease epidemics. In this study, we characterized an insertional mutant Z39P105 with a defect in sexual development and identified a gene encoding a putative transcription factor designated as MYT1. This gene contains a Myb DNA-binding domain and is conserved in the subphylum Pezizomycotina of Ascomycota. The MYT1 protein fused with green fluorescence protein localized in nuclei, which supports its role as a transcriptional regulator. The MYT1 deletion mutant showed similar phenotypes to the wild-type strain in vegetative growth, conidia production and germination, virulence, and mycotoxin production, but had defect in female fertility. A mutant overexpressing MYT1 showed earlier germination, faster mycelia growth, and reduced mycotoxin production compared to the wild-type strain, suggesting that improper MYT1 expression affects the expression of genes involved in the cell cycle and secondary metabolite production. This study is the first to characterize a transcription factor containing a Myb DNA-binding domain that is specific to sexual development in G. zeae. PMID:21984921

  19. 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

  20. 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

  1. Conservation of PHO pathway in ascomycetes and the role of Pho84 PARUL TOMAR

    E-print Network

    Sinha, Himanshu

    of PHO pathway, their roles in maintaining phosphate homeostasis in yeast and their conservation across, it is crucial for living organisms to maintain proper phosphate homeostasis, as any imbalance (hyper- or hypo phosphate homeostasis such as genes required for phosphate uptake from extracel- lular environment

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During the past two years a project has been undertaken to study endophytic fungi associated with plants growing in El Eden Ecological Reserve, located in the State of Quintana Roo in the northeastern part of the Yucatan Peninsula of México. Asymptomatic, healthy leaves were collected, surface steri...

  3. 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...

  4. 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...

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

    PubMed

    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 (IC(50) value approximately 1 muM) 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 T(i) 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 muM. 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

  6. 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 ...

  7. Wickerhamomyces arborarius f.a., sp. nov., an ascomycetous yeast species found in arboreal

    E-print Network

    Harrington, Thomas C.

    to the genera Issatchenkia, Pichia, Starmera and Williopsis. Using a multigene sequencing approach, Kurtzman), including all those pre- viously assigned to the genus Issatchenkia. Pichia dryadoides and Pichia quercuum

  8. 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

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

    PubMed Central

    L?kös, 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. L?kös et S. -O. Oh, Loekoesia S. Y. Kondr., S. -O. Oh et J. -S. Hur and Olegblumia S. Y. Kondr., L. L?kös et J. -S. Hur. Three new combinations for the type species of these genera are proposed. PMID:26539034

  10. 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. ...

  11. Toll-like receptor 4-interacting SPA4 peptide suppresses the NLRP3 inflammasome in response to LPS and ATP stimuli.

    PubMed

    Ramani, Vijay; Awasthi, Shanjana

    2015-12-01

    Inflammation is induced because of interplay among multiple signaling pathways and molecules during infectious and noninfectious tissue injuries. Crosstalk between Toll-like receptor-4 signaling and the neuronal apoptosis inhibitor protein, major histocompatibility class 2 transcription activator, incompatibility locus protein from Podospora anserina, and telomerase-associated protein (NACHT), leucine-rich repeat (LRR), and pyrin domain-containing protein 3 (NLRP3) inflammasome against pathogen- or damage-associated molecular patterns can cause exaggerated inflammation. We previously established that the Toll-like receptor-4-interacting SPA4 peptide suppresses gram-negative bacterial lipopolysaccharide (Toll-like receptor-4 ligand)-induced nuclear factor-?B and inflammatory response. In the present study, we hypothesized that the SPA4 peptide exerts its anti-inflammatory effects by suppressing the crosstalk between Toll-like receptor-4 signaling and the NLRP3 inflammasome. We evaluated binding of the lipopolysaccharide-ligand to cell-surface Toll-like receptor-4 in the presence or absence of adenosine triphosphate (an NLRP3 inflammasome inducer) by flow cytometry. The expression and activity of NLRP3 inflammasome-related parameters were studied in cells challenged with lipopolysaccharide and adenosine triphosphate using molecular and immunologic methods. The cells were challenged with lipopolysaccharide and treated with SPA4 peptide before (pre-adenosine triphosphate) or after (post-adenosine triphosphate) secondary challenge with adenosine triphosphate. Our data demonstrate that the Toll-like receptor-4-interacting SPA4 peptide does not affect the binding of lipopolysaccharide to Toll-like receptor-4 in the presence or absence of adenosine triphosphate. We also found that the SPA4 peptide inhibits mRNA and cellular protein levels of pro-interleukin-1? and NLRP3, formation of the NLRP3 inflammasome, caspase activity, and release of interleukin-1?. Furthermore, the SPA4 peptide treatment reduced the secreted levels of interleukin-1? from cells overexpressing Toll-like receptor-4 compared with cells expressing the dominant-negative form of Toll-like receptor-4. Together our results suggest that the SPA4 peptide exerts its anti-inflammatory activity by suppressing Toll-like receptor-4-priming of the NLRP3 inflammasome. PMID:26254306

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

    PubMed

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

    2010-06-01

    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. 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

  14. PHYLOGENETIC ANALYSIS IDENTIFIES THE "MEGABACTERIUM" OF BIRDS AS A NOVEL ANAMORPHIC ASCOMYCETOUS YEAST, MACRORHABDUS ORNITHOGASTER GEN. NOV, SP. NOV.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organisms commonly referred to as megabacteria colonize the gastric isthmus of many species of birds. They are weakly Gram-positive, PAS-positive, and stain with silver stains. Previous studies show that they have a nucleus and a cell wall similar to that seen in fungi. Calcofluor white M2R stain...

  15. 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

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

    PubMed

    Daniel, Heide-Marie; Lachance, Marc-André; Kurtzman, Cletus P

    2014-07-01

    Multigene phylogenies have been instrumental in revising the classification of ascosporic (teleomorph) yeasts in a natural system based on lines of descent. Although many taxonomic changes have already been implemented for teleomorph taxa, this is not yet the case for the large genus Candida and smaller anascosporic (anamorph) genera. In view of the recently introduced requirement that a fungal species or higher taxon be assigned only a single valid name under the new International Code of Nomenclature for algae, fungi, and plants (Melbourne Code), the current species of Candida and other anamorph yeast genera must undergo revision to make genus membership consistent with phylogenetic affinities. A review of existing data and analyses shows that certain Candida species may be assigned to teleomorph genera with high confidence using multigene phylogenies. Candida species that form well-circumscribed phylogenetic clades without any teleomorph member justify the creation of new genera. However, a considerable number of Candida species sit at the end of isolated and often long branches, and hence cannot be assigned to larger species groups. They should be maintained in Candida sensu lato until studied by multigene analyses in datasets with comprehensive taxon sampling. The principle of name stability has to be honoured to the largest extent compatible with a natural classification of Candida species. PMID:24748333

  17. Soudanones A-G: Antifungal Isochromanones from the Ascomycetous Fungus Cadophora sp. Isolated from an Iron Mine.

    PubMed

    Rusman, Yudi; Held, Benjamin W; Blanchette, Robert A; Wittlin, Sergio; Salomon, Christine E

    2015-06-26

    One new isochromane (pseudoanguillosporin C, 2), seven isochromanones (soudanones A-G, 3-9), and six known analogues including 10 and 11 were isolated from a culture of the fungus Cadophora sp. 10-5-2 M, collected from the subterranean 10th level of the Soudan Underground Iron Mine in Minnesota. All of the compounds were tested against a panel of microbial pathogens, and 2, 3, 10, and 11 were found to have activity against Cryptococcus neoformans (MIC = 35, 40, 20, and 30 ?g/mL, respectively). Compound 11 was also active against Candida albicans, with an MIC of 40 ?g/mL. PMID:26035018

  18. 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...

  19. 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

  20. The Wood Rot Ascomycete Xylaria polymorpha Produces a Novel GH78 Glycoside Hydrolase That Exhibits ?-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 ?-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., ?-l-rhamnopyranoside and ?-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

  1. 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...

  2. 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

  3. Cch1 and Mid1 Are Functionally Required for Vegetative Growth under Low-Calcium Conditions in the Phytopathogenic Ascomycete Botrytis cinerea

    PubMed Central

    Harren, Karin

    2013-01-01

    In the filamentous phytopathogen Botrytis cinerea, the Ca2+/calcineurin signaling cascade has been shown to play an important role in fungal growth, differentiation, and virulence. This study deals with the functional characterization of two components of this pathway, the putative calcium channel proteins Cch1 and Mid1. The cch1 and mid1 genes were deleted, and single and double knockout mutants were analyzed during different stages of the fungal life cycle. Our data indicate that Cch1 and Mid1 are functionally required for vegetative growth under conditions of low extracellular calcium, since the growth of both deletion mutants is strongly impaired when they are exposed to the Ca2+-chelating agents EGTA and 1,2-bis(o-aminophenoxy)ethane-N,N,N?,N?-tetraacetic acid (BAPTA). The impact of external Ca2+ was investigated by supplementing with CaCl2 and the ionophore A23187, both of which resulted in elevated growth for all mutants. However, deletion of either gene had no impact on germination, sporulation, hyphal morphology, or virulence. By use of the aequorin reporter system to measure intracellular calcium levels, no differences between the mutant strains and the wild type were obtained. Localization studies revealed a subcellular distribution of the Mid1–green fluorescent protein (GFP) fusion protein in network-like filaments, probably the endoplasmic reticulum (ER) membranes, indicating that Mid1 is not a plasma membrane-located calcium channel in B. cinerea. PMID:23475703

  4. The wood rot ascomycete Xylaria polymorpha produces a novel GH78 glycoside hydrolase that exhibits ?-L-rhamnosidase and feruloyl esterase activities and releases hydroxycinnamic acids from lignocelluloses.

    PubMed

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

    2012-07-01

    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 ?-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., ?-L-rhamnopyranoside and ?-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

  5. 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...

  6. DNA Sequence Characterization and Molecular Evolution of MAT1 and MAT2 Mating-Type Loci of the Self-Compatible Ascomycete Mold Neosartorya fischeri?

    PubMed Central

    Rydholm, C.; Dyer, P. S.; Lutzoni, F.

    2007-01-01

    Degenerate PCR and chromosome-walking approaches were used to identify mating-type (MAT) genes and flanking regions from the homothallic (sexually self-fertile) euascomycete fungus Neosartorya fischeri, a close relative of the opportunistic human pathogen Aspergillus fumigatus. Both putative alpha- and high-mobility-group-domain MAT genes were found within the same genome, providing a functional explanation for self-fertility. However, unlike those in many homothallic euascomycetes (Pezizomycotina), the genes were not found adjacent to each other and were termed MAT1 and MAT2 to recognize the presence of distinct loci. Complete copies of putative APN1 (DNA lyase) and SLA2 (cytoskeleton assembly control) genes were found bordering the MAT1 locus. Partial copies of APN1 and SLA2 were also found bordering the MAT2 locus, but these copies bore the genetic hallmarks of pseudogenes. Genome comparisons revealed synteny over at least 23,300 bp between the N. fischeri MAT1 region and the A. fumigatus MAT locus region, but no such long-range conservation in the N. fischeri MAT2 region was evident. The sequence upstream of MAT2 contained numerous candidate transposase genes. These results demonstrate a novel means involving the segmental translocation of a chromosomal region by which the ability to undergo self-fertilization may be acquired. The results are also discussed in relation to their significance in indicating that heterothallism may be ancestral within the Aspergillus section Fumigati. PMID:17384199

  7. Starmerella aceti f.a., sp. nov., an ascomycetous yeast species isolated from fungus garden of the leafcutter ant Acromyrmex balzani.

    PubMed

    Melo, Weilan G P; Arcuri, Silvio L; Rodrigues, Andre; Morais, Paula B; Meirelles, Lucas A; Pagnocca, Fernando C

    2014-04-01

    A novel yeast species was recovered from the fungus garden of the leaf-cutting ant Acromyrmex balzani (Hymenoptera: Formicidae). The growth of the novel yeast species is limited by its ability to metabolize only a few carbon and nitrogenous compounds. A remarkable characteristic of this strain is the vigorous growth in 1?% acetic acid. Sequence analysis of the D1/D2 domains of the LSU rRNA gene showed that the novel species belongs to the Starmerella clade and is phenotypically and genetically divergent from currently recognized species in this clade. Described here as Starmerella aceti f.a., sp. nov., it differs by 37 nucleotide substitutions in the D1/D2 region from Starmerella jinningensis CBS 11864(T), the most closely related species. The type strain of Starmerella aceti sp. nov. is TO 125(T) (?=?CBMAI 1594(T)?=?CBS 13086(T)). PMID:24566828

  8. 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....

  9. 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

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

    NASA Astrophysics Data System (ADS)

    Skulachev, Vladimir P.

    A concept is presented considering aging of living organisms as a final step of their ontogenetic program. It is assumed that such an aging program was invented by biological evolution to facilitate the evolutionary process. Indications are summarized suggesting that controlled production of toxic forms of oxygen (so called reactive oxygen species) by respiring intracellular organelles (mitochondria) is an obligatory component of the aging program. First results of a research project devoted to an attempt to interrupt aging program by antioxidants specifically addressed to mitochondria have been described. Within the framework of the project, antioxidants of a new type (SkQ) were synthesized. SkQs are composed of (i) plastoquinone (an antioxidant moiety), (ii) a penetrating cation, and (iii) a decane or pentane linker. Using planar bilayer phospholipid membranes, we selected SkQ derivatives of the highest penetrability, namely plastoquinonyl decyl triphenylphosphonium (SkQ1), plastoquinonyl decyl rhodamine 19 (SkQR1), and methylplastoquinonyl decyl triphenylphosphonium (SkQ3). Anti- and prooxidant properties of these substances and also of ubiquinonyl-decyl-triphenylphosphonium (MitoQ) were tested in isolated mitochondria. Micromolar concentrations of cationic quinones are found to be very strong prooxidants, but in the lower (sub-micromolar) concentrations they display antioxidant activity which decreases in the series SkQ1 = SkQR1 > SkQ3 > MitoQ. Thus, the window between the anti- and prooxidant effects is the smallest for MitoQ and the largest for SkQ1 and SkQR1. SkQ1 is rapidly reduced by complex III of the mitochondrial respiratory chain, i.e. it is a rechargeable antioxidant. Extremely low concentrations of SkQ1 and SkQR1 completely arrest the H2O2-induced apoptosis in human fibroblasts and HeLa cells (for SkQ1, C 1/2 = 8 · 10-9M). Higher concentrations of SkQ1 are required to block necrosis initiated by reactive oxygen species (ROS). In mice, SkQ1 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.

  11. 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...

  12. e-Fungi: a data resource for comparative analysis of fungal genomes

    E-print Network

    Hedeler, Cornelia; Wong, Han Min; Cornell, Michael J.; Alam, Intikhab; Soanes, Darren M.; Rattray, Magnus; Hubbard, Simon J.; Talbot, Nicholas J.; Oliver, Stephen G.; Paton, Norman W.

    2007-11-20

    pathogen filamentous JGI Gibberella zeae Ascomycete – Sordariomycetes plant pathogen filamentous Broad Magnaporthe grisea Ascomycete – Sordariomycetes plant pathogen filamentous Broad Chaetomium globosum Ascomycete – Sordariomycetes animal pathogen... nodorum 148 83 37 Sclerotinia sclerotiorum 92 70 13 Botrytis cinerea 79 53 18 Trichoderma reesei 71 43 10 Gibberella zeae 107 65 14 Chaetomium globosum 89 68 14 Magnaporthe grisea 133 67 30 Neurospora crassa 39 33 2 Encephalitazoon cuniculi 0 0 0Page 12...

  13. 21 CFR 173.150 - Milk-clotting enzymes, microbial.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... fermentation process may be safely used in the production of cheese in accordance with the following prescribed... fermentation process: (1) Endothia parasitica classified as follows: Class, Ascomycetes; order,...

  14. 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...

  15. Translocations used to generate chromosome segment duplications in Neurospora can disrupt genes and create novel open reading frames.

    PubMed

    Singh, Parmit K; Iyer, Srividhya V; Sowjanya, T Naga; Raj, B Kranthi; Kasbekar, Durgadas P

    2010-12-01

    In Neurospora crassa, crosses between normal sequence strains and strains bearing some translocations can yield progeny bearing a duplication (Dp) of the translocated chromosome segment. Here, 30 breakpoint junction sequences of 12 Dp-generating translocations were determined. The breakpoints disrupted 13 genes (including predicted genes), and created 10 novel open reading frames. Insertion of sequences from LG III into LG I as translocation T(UK8-18) disrupts the eat-3 gene, which is the ortholog of the Podospora anserine gene ami1. Since ami1-homozygous Podospora crosses were reported to increase the frequency of repeat-induced point mutation (RIP), we performed crosses homozygous for a deficiency in eat-3 to test for a corresponding increase in RIP frequency. However, our results suggested that, unlike in Podospora, the eat-3 gene might be essential for ascus development in Neurospora. Duplication-heterozygous crosses are generally barren in Neurospora; however, by using molecular probes developed in this study, we could identify Dp segregants from two different translocation-heterozygous crosses, and using these we found that the barren phenotype of at least some duplication-heterozygous crosses was incompletely penetrant. PMID:21289436

  16. Phylogenetic relationships among Taphrina, Saitoella, and other higher fungi.

    PubMed

    Nishida, H; Sugiyama, J

    1993-03-01

    To determine the phylogenetic placement of the major groups of higher fungi, we sequenced the DNA sequences from the small-subunit ribosomal RNA (18S rRNA) coding regions from Taphrina wiesneri (synonym: T. cerasi) and Saitoella complicata and compared them to 18S rRNA sequences from the oomycetes, chytridiomycetes, zygomycetes, ascomycetes, and basidiomycetes. Here we demonstrate that the ascomycetes have at least two major evolutionary lineages. Taphrina wiesneri and Saitoella complicata form a monophyletic branch that diverged prior to the separation of other ascomycetes. The same treatment could be accorded to Schizosaccharomyces pombe. PMID:8487639

  17. Ecology 2005 93, 244255

    E-print Network

    Thomas, David D.

    the establishment of ectomycorrhizal vegetation. Key-words: ascomycetes, Cedar Creek LTER, diversity, ectomycorrhiza 2261; fax +4 612 625 5212; e-mail dicki017@umn.edu). #12;245 Ectomycorrhiza at forest edges © 2005

  18. 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...

  19. Protoascon missouriensis, a complex fossil microfungus revisited

    E-print Network

    Taylor, Thomas N.; Krings, Michael; Klavins, Sharon D.; Taylor, Edith L.

    2005-03-14

    The Carboniferous microfungus Protoascon missouriensis has been interpreted variously as an ascomycete, chytridiomycete, zygomycete and oomycete. We offer a more complete interpretation based on a re-examination of the type material that suggests...

  20. Didymella rabiei primary inoculum release from chickpea debris in relation to weather variables in the Pacific Northwest of the United States.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Didymella rabiei (anamorph: Ascochyta rabiei), the ascomycete fungus that causes Ascochyta blight of chickpea, produces pseudothecia on overwintered chickpea debris. Ascospores released from pseudothecia are thought to constitute an important primary inoculum source for Ascochyta blight epidemics i...

  1. Complex patterns of speciation in cosmopolitan "rock posy" lichens - an integrative approach to discovering and delimiting fungal species in the lichen-forming rhizoplaca melanophthalma speciescomplex

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A growing body of evidence indicates that morphology-based species circumspection of lichenized ascomycetes greatly misrepresents the number of existing species. Recently it has been demonstrated that population-level processes operating within diverging populations can facilitate the identification...

  2. Iosif Vaisman Email: ivaisman@gmu.edu

    E-print Network

    Vaisman, Iosif

    Roundworms 1 16 11 28 Plants 5 33 80 118 Land plants 3 29 73 105 Fungi 17 107 59 183 Ascomycetes 13 83 38 134 Protein Structure Initiative 2001 2002 2003 2004 2013 Selected Cloned Expressed Purified Crystallized

  3. 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 ...

  4. Molecular Characterization of MADS-BOX Transcription Factors and Analysis of Field Population Diversity in the Maize Pathogen Fusarium verticillioides 

    E-print Network

    Ortiz, Carlos S

    2013-04-10

    Fusarium verticillioides (Teleomorph Giberella moniliformis) is an ascomycete fungus responsible for ear and stalk rots of maize. Most importantly, it produces a group of mycotoxins called fumonisins upon colonization of maize kernels. Fumonisin B1...

  5. Comparative Functional Genomics of the Fission Yeasts

    E-print Network

    Regev, Aviv

    The fission yeast clade—comprising Schizosaccharomyces pombe, S. octosporus, S. cryophilus, and S. japonicus—occupies the basal branch of Ascomycete fungi and is an important model of eukaryote biology. A comparative ...

  6. Sex, outcrossing and mating types: unsolved questions in fungi and beyond

    E-print Network

    López-Villavicencio, Manuela

    fuse. The long-term persistence of eukaryotes relying exclusively on asexual reproduction is rare Keywords: ascomycete; asexual reproduction; basidiomycete; breeding systems; diploid selfing; gametophytic- nance of asexual vs. sexual reproduction a

  7. Cytochrome P450 Monooxygenase CYP53 Family in Fungi: Comparative Structural and Evolutionary Analysis and Its Role as a Common Alternative Anti-Fungal Drug Target

    PubMed Central

    Jawallapersand, Poojah; Mashele, Samson Sitheni; Kova?i?, Lidija; Stojan, Jure; Komel, Radovan; Pakala, Suresh Babu; Kraševec, Nada; Syed, Khajamohiddin

    2014-01-01

    Cytochrome P450 monooxygenases (CYPs/P450s) are heme-thiolate proteins whose role as a drug target against pathogenic microbes has been explored because of their stereo- and regio-specific oxidation activity. We aimed to assess the CYP53 family's role as a common alternative drug target against animal (including human) and plant pathogenic fungi and its role in fungal-mediated wood degradation. Genome-wide analysis of fungal species revealed the presence of CYP53 members in ascomycetes and basidiomycetes. Basidiomycetes had a higher number of CYP53 members in their genomes than ascomycetes. Only two CYP53 subfamilies were found in ascomycetes and six subfamilies in basidiomycetes, suggesting that during the divergence of phyla ascomycetes lost CYP53 P450s. According to phylogenetic and gene-structure analysis, enrichment of CYP53 P450s in basidiomycetes occurred due to the extensive duplication of CYP53 P450s in their genomes. Numerous amino acids (103) were found to be conserved in the ascomycetes CYP53 P450s, against only seven in basidiomycetes CYP53 P450s. 3D-modelling and active-site cavity mapping data revealed that the ascomycetes CYP53 P450s have a highly conserved protein structure whereby 78% amino acids in the active-site cavity were found to be conserved. Because of this rigid nature of ascomycetes CYP53 P450s' active site cavity, any inhibitor directed against this P450 family can serve as a common anti-fungal drug target, particularly toward pathogenic ascomycetes. The dynamic nature of basidiomycetes CYP53 P450s at a gene and protein level indicates that these P450s are destined to acquire novel functions. Functional analysis of CYP53 P450s strongly supported our hypothesis that the ascomycetes CYP53 P450s ability is limited for detoxification of toxic molecules, whereas basidiomycetes CYP53 P450s play an additional role, i.e. involvement in degradation of wood and its derived components. This study is the first report on genome-wide comparative structural (gene and protein structure-level) and evolutionary analysis of a fungal P450 family. PMID:25222113

  8. Maintaining heterokaryosis in pseudo-homothallic fungi

    PubMed Central

    Grognet, Pierre; Silar, Philippe

    2015-01-01

    Among all the strategies displayed by fungi to reproduce and propagate, some species have adopted a peculiar behavior called pseudo-homothallism. Pseudo-homothallic fungi are true heterothallics, i.e., they need 2 genetically-compatible partners to mate, but they produce self-fertile mycelium in which the 2 different nuclei carrying the compatible mating types are present. This lifestyle not only enables the fungus to reproduce without finding a compatible partner, but also to cross with any mate it may encounter. However, to be fully functional, pseudo-homothallism requires maintaining heterokaryosis at every stage of the life cycle. We recently showed that neither the structure of the mating-type locus nor hybrid-enhancing effect due to the presence of the 2 mating types accounts for the maintenance of heterokaryosis in the pseudo-homothallic fungus P. anserina. In this addendum, we summarize the mechanisms creating heterokaryosis in P. anserina and 2 other well-known pseudo-homothallic fungi, Neurospora tetrasperma and Agaricus bisporus. We also discuss mechanisms potentially involved in maintaining heterokaryosis in these 3 species. PMID:26479494

  9. The Genome and Development-Dependent Transcriptomes of Pyronema confluens: A Window into Fungal Evolution

    PubMed Central

    Traeger, Stefanie; Altegoer, Florian; Freitag, Michael; Gabaldon, Toni; Kempken, Frank; Kumar, Abhishek; Marcet-Houben, Marina; Pöggeler, Stefanie; Stajich, Jason E.; Nowrousian, Minou

    2013-01-01

    Fungi are a large group of eukaryotes found in nearly all ecosystems. More than 250 fungal genomes have already been sequenced, greatly improving our understanding of fungal evolution, physiology, and development. However, for the Pezizomycetes, an early-diverging lineage of filamentous ascomycetes, there is so far only one genome available, namely that of the black truffle, Tuber melanosporum, a mycorrhizal species with unusual subterranean fruiting bodies. To help close the sequence gap among basal filamentous ascomycetes, and to allow conclusions about the evolution of fungal development, we sequenced the genome and assayed transcriptomes during development of Pyronema confluens, a saprobic Pezizomycete with a typical apothecium as fruiting body. With a size of 50 Mb and ?13,400 protein-coding genes, the genome is more characteristic of higher filamentous ascomycetes than the large, repeat-rich truffle genome; however, some typical features are different in the P. confluens lineage, e.g. the genomic environment of the mating type genes that is conserved in higher filamentous ascomycetes, but only partly conserved in P. confluens. On the other hand, P. confluens has a full complement of fungal photoreceptors, and expression studies indicate that light perception might be similar to distantly related ascomycetes and, thus, represent a basic feature of filamentous ascomycetes. Analysis of spliced RNA-seq sequence reads allowed the detection of natural antisense transcripts for 281 genes. The P. confluens genome contains an unusually high number of predicted orphan genes, many of which are upregulated during sexual development, consistent with the idea of rapid evolution of sex-associated genes. Comparative transcriptomics identified the transcription factor gene pro44 that is upregulated during development in P. confluens and the Sordariomycete Sordaria macrospora. The P. confluens pro44 gene (PCON_06721) was used to complement the S. macrospora pro44 deletion mutant, showing functional conservation of this developmental regulator. PMID:24068976

  10. The phylogeny of yeasts—A cladistic analysis

    NASA Astrophysics Data System (ADS)

    Sun, Xiuqin; Wu, Baoling

    1992-12-01

    Cladistic analysis was used to clarify the phylogeny of 16 genera of yeasts whose great morphological differences and inclusion in different classification systems resulted in controversies over the taxonomy of seven genera such as Crypeococcus. etc. Some scholars suggest that they belong to Ascomycetes, but others think they belong to fungi imperfecti. After comprehensive cladistic analysis of many genetic characters, the authors consider that the above-mentioned seven genera of yeasts developed in parallel with Ascomycetes so that they should belong to one and the same developmental system.

  11. A Review of the Phylogeny and Biology of the Diaporthales

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ascomycete order Diaporthales is reviewed based on recent phylogenetic data that outline the families and integrate related asexual fungi. The order is now considered to consist of nine families one of which is newly recognized as the Schizoparmeaceae fam. nov. and two families are recircumscri...

  12. Biological and Chemical Complexity of Fusarium proliferatum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The heterothallic ascomycete Fusarium proliferatum (teleomorph Gibberella intermedia) is a genetically diverse biological and phylogenetic species with a worldwide distribution and an unusually broad host range. F. proliferatum is a frequent component of the Fusarium ear rot complexes of maize and ...

  13. Babjeviella Kurtzman & M. Suzuki (2010)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes the ascomycete yeast genus Babjeviella and is to be published in The Yeasts, A Taxonomic Study, 5th edition. The genus Babjeviella has one known species, B. inositovora, which is represented by three strains, one each from the U.S., Canada and Russia. The genus is phylogenet...

  14. Horizontal Transfer of a Nitrate Assimilation Gene Cluster and Ecological Transitions in Fungi: A

    E-print Network

    Hibbett, David S.

    nitrate transporter; euknr, which codes for nitrate reductase; and NAD(P)H- nir, which codes for nitrite a basidiomycete (mushrooms and smuts) to an ancestor of the ascomycetous mold Trichoderma reesei. Phylogenetic, abbreviated fHANT-AC, encodes a high affinity nitrate transporter (NRT2, TCDB 2.A.1.8.5) along with a nitrate

  15. Mla- and Rom1-mediated control of microRNA398 and chloroplast copper/zinc superoxide dismutase regulates cell death in response to the barley powdery mildew fungus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Barley Mla (Mildew resistance locus a) confers allele-specific interactions with natural variants of the ascomycete fungus, Blumeria graminis f. sp. hordei (Bgh), causal agent of powdery mildew disease. Significant reprogramming of host gene expression occurs upon infection by this obligate biotrop...

  16. Trigonopsis Schachner emend. Kurtzman & Robnett (2007)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The chapter describes the asexual ascomycete yeast genus Trigonopsis and is to be published in “The Yeasts, A Taxonomic Study, 5th edition.” The genus Trigonopsis has four known species and T. variabilis is famous for producing triangular cells, whereas the other described species do not. Multigen...

  17. Understanding the coevolution of rice blast resistance gene Pi-ta and Magnaporthe oryzae avirulence gene AVR-Pita

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice blast disease caused by the filamentous ascomycetous fungus Magnaporthe oryzae remains to be one of the most serious threats for food security globally. Using resistance (R) genes in integrated cultural practices has been the most powerful practice for rice crop protection. Genetic analysis s...

  18. Intercontinental genetic structure of the fungal grapevine pathogen Eutypa lata

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ascomycete fungus Eutypa lata, causal agent of Eutypa dieback of grapevine (Vitis vinifera), impacts all vineyard production systems worldwide. Our objectives were to characterize the population structure of E. lata at different geographical scales to identify migration patterns through ascospor...

  19. Global genetic structure of the fungal grapevine pathogen Eutypa lata

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ascomycete fungus Eutypa lata is a trunk pathogen of cultivated grapevine (Vitis vinifera) in all major grape-growing regions of the world. Throughout its geographic range, it is considered a generalist pathogen that can complete its life cycle on a broad range of hosts. To decipher the cosmopol...

  20. Cryptic Sexuality Influences Aflatoxigenicity in Aspergillus parasiticus and A. flavus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ascomycetous fungi of the genus Aspergillus comprise a wide variety of species of biotechnological importance as well as pathogens and toxin producers. Recent studies report A. fumigatus to be heterothallic and possibly undergoing sexual reproduction. We therefore investigated whether compatible mat...

  1. Naumovozyma Kurtzman (2008)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes the ascomycetous yeast genus Naumovozyma, which was recognized from multigene deoxyribonucleic acid (DNA) sequence analysis. The genus has two describes species, which were formerly classified in the genus Saccharomyces. The species reproduce by multilateral budding but do not...

  2. Millerozyma Kurtzman & M. Suzuki (2010)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes the ascomycete yeast genus Millerozyma and is to be published in "The Yeasts, A Taxonomic Study, 5th edition." The genus Millerozyma has two described species that were earlier assigned to the genus Pichia, but gene sequence analysis showed that the species, now reclassified ...

  3. New Phomopsis species identified from wood cankers in eastern North American vineyards.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phomopsis cane and leaf spot, caused by the Ascomycete fungus Phomopsis viticola, is a destructive fruit and foliar disease in eastern North American vineyards. The pathogen typically attacks green tissues, but can also cause wood cankers, presumably due to infection of pruning wounds, as is the cas...

  4. Diversity, Pathogenicity And Control of Verticillium Species.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The genus Verticillium is a cosmopolitan group of ascomycetous fungi, encompassing phytopathogenic species that cause vascular wilts of plants. Two of these species, V. dahliae and V. albo-atrum, cause billions of dollars in annual crop losses worldwide. The soil habitat of these species, the exte...

  5. Molecular phylogeny of Sydowiellaceae, resolving the position of Cainiella

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cainiella is an ascomycete genus associated with arctic alpine plants. The systematic position of Cainiella has been unclear for a long time with current classifications placing the genus in either Sordariales or Xylariales. Our molecular results, based on mtSSU, ITS and nLSU rDNA data, clearly show...

  6. Hyphopichia von Arx & van der Walt (1976)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes the ascomycete yeast genus Hyphopichia and is to be published in “The Yeasts, A Taxonomic Study, 5th edition.” The genus Hyphopichia was derived from the genus Pichia and accepted as valid following a multigene phylogenetic analysis. At present, there are two species assigne...

  7. Yamadazyma Billon-Grand (1989)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes the ascomycete yeast genus Yamadazyma and is to be published in "The Yeasts, a Taxonomic Study, 5th edition." The genus Yamadazyma was derived from the genus Pichia following a multigene phylogenetic analysis. At present, there are 6 known species assigned to the genus. Sev...

  8. Real-time PCR detection of the boxwood blight pathogen Calonectria pseudonaviculata

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Boxwood blight is a newly emergent, destructive disease of boxwood (genus Buxus), caused by the ascomycete fungus Calonectria pseudonaviculata. Initially identified in Europe in the mid-1990s, the disease was first reported in the U.S. in CT, NC and VA during October 2011. In less than four months, ...

  9. Basis for inhibition of Pyrenophora teres by Laetisaria arvalis, a scanning and transmission electron microscopic study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The broadly occurring foliar disease of barley, net blotch is caused by Pyrenophora teres, an ascomycete and could result in significant yield loss under heavy disease pressure. The basidiomycete, Laetisaria arvalis has been reported to have biological control activity over some plant pathogens. In ...

  10. The finished genomic sequence of the Septoria tritici blotch pathogen Mycosphaerella graminicola

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mycosphaerella graminicola is the haploid ascomycete that causes Septoria tritici blotch, one of the most important diseases of wheat worldwide. This pathogen is phylogenetically distinct from other fungi that have been sequenced and is hemibiotrophic; early infection is biotrophic, followed by a s...

  11. A spatial model for predicting effects of climate change on Swiss needle cast disease severity in the Pacific Northwest

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Swiss needle cast disease of Douglas-fir is caused by the ascomycete fungus Phaeocryptopus gaeumannii. Symptoms of the disease are foliage chlorosis and premature needle abscission due to occlusion of stomata by the ascocarps of the pathogen, resulting in impaired needle gas exchange. Severe defol...

  12. Hyphomycetes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hyphomycetes are anamorphic forms of ascomycetes or basidiomycetes. In many instances, teleomorphs appear to have been lost over evolutionary time. They are identified on the basis of conidial shape and color, number and position of conidial septa, degree of aggregation of conidiophores, and mode ...

  13. Conservation and Evolution of Cis-Regulatory Systems

    E-print Network

    Babu, M. Madan

    Conservation and Evolution of Cis-Regulatory Systems in Ascomycete Fungi Audrey P. Gasch1¤*, Alan M 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

  14. MVE1 Encoding the velvet gene product homolog in Mycosphaerella graminicola is associated with aerial mycelium formation, melanin biosynthesis, hyphal swelling, and light signaling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ascomycete fungus Mycosphaerella graminicola is an important pathogen of wheat that causes the disease septoria tritici blotch. Despite the serious impact of M. graminicola on wheat production worldwide, knowledge about its molecular biology is limited. The velvet gene, veA, is one of the key re...

  15. Emergence of a new disease as a result of interspecific virulence gene transfer

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ToxA gene of the ascomycete fungal pathogen Pyrenophora tritici-repentis controls specificity of the interaction with its host, wheat. Host genotypes carrying dominant alleles of Tsn1 are susceptible to isolates of the pathogen expressing ToxA. Pyrenophora tritici-repentis isolates lacking ToxA ...

  16. Cephaloascus Hanawa (1920)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes the ascomycete yeast genus Cephaloascus and is to be published in “The Yeasts, A Taxonomic Study, 5th edition.” The genus Cephaloascus has two species. One, C. albidus, has been isolated from spoiled cranberry pumace, and the second, C. fragrans, is predominantly isolated fr...

  17. Meyerozyma Kurtzman & M. Suzuki (2010)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes the ascomycete yeast genus Meyerozyma and is to be published in “The Yeasts, A Taxonomic Study,” 5th edition. The genus Meyerozyma is newly described and was derived from the genus Pichia following a multigene phylogenetic analysis. At present, there are two species assigned...

  18. Draft Genome Sequence of the Dimorphic Yeast Yarrowia lipolytica Strain W29

    PubMed Central

    Pomraning, Kyle R.

    2015-01-01

    Here, we present the draft genome sequence of the dimorphic ascomycete yeast Yarrowia lipolytica strain W29 (ATCC 20460). Y. lipolytica is a commonly employed model for the industrial production of lipases, small molecules, and more recently for its ability to accumulate lipids. PMID:26607882

  19. Protomyces Unger (1833)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes the ascomycetous fungal genus Protomyces and is to be published in "The Yeasts, A Taxonomic Study, 5th edition." Species of the genus Protomyces are plant pathogens that attack asters, wild celery, coriander and certain other plants. Symptoms include disruption of stems, lea...

  20. Taiwanascus samuelsii sp. nov., an addition to Niessliaceae from the Western Ghats, Kerala, India

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new species of Taiwanascus, T. samuelsii, was collected from southern parts of Western Ghats on dead branches of Anacardium occidentale and is described. The new cleistothecial ascomycete is different from the type and only species in Taiwanascus, T. tetrasporus, in cleistothecial size, setae, and...

  1. First report of powdery mildew caused by Podosphaera leucotricha on Callery pear in North America

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Podosphaera leucotricha (Ellis & Everh.) E.S. Salmon (Ascomycetes, Erysiphales) is the etiological agent of a powdery mildew disease that occurs on rosaceous plants, primarily Malus and Pyrus. This fungus is nearly circumglobal. In May 2009, leaves of Bradford pear (Pyrus calleryana Decne.), some di...

  2. AFLP ANALYSIS OF A WORLDWIDE COLLECTION OF DIDYMELLA BRYONIAE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Didymella bryoniae (anamorph Phoma cucurbitacearum) is an Ascomycete fungus that causes gummy stem blight, a foliar disease that occurs on cucurbits in greenhouses and fields throughout the world. In a previous study using RAPD analysis, little genetic diversity was found among isolates of D. bryon...

  3. AGONOMYCETES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agonomycetes are fungi which usually produce neither sexual (meiotic) nor asexual (mitotic) spores. Some members of this artificial (non-phylogenetic) group are related to ascomycetes, while others are related to basidiomycetes. Many members form spore-like propagules called chlamydospores, papulos...

  4. Schwanniomyces Klocker emend. M. Suzuki & Kurtzman (2010)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes the ascomycete yeast genus Schwanniomyces and is to be published in The Yeasts, A Taxonomic Study, 5th edn. The genus Schwanniomyces has seven assigned species, many worldwide in distribution. Schwanniomyces is one of the few yeast genera with species that seem to live in th...

  5. POPULATION STRUCTURE AND DIVERSITY OF EUTYPA LATA FROM MEDITERRANEAN GRAPE-GROWING REGIONS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Eutypa lata is an ascomycete fungus causing dieback of grape (Vitis vinifera). We examined the genetic structure of eight vineyard collections using nine polymorphic microsatellite loci. In California, isolates were collected from four vineyards (CS1, CS2, M1 and M2) separated by distances of 50 m t...

  6. Colletotrichum fungal pathogens and symbionts of ornamental nursery and landscape plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fungi in the ascomycete genus Colletotrichum are ranked by the plant pathology community as one of the ten most economically and scientifically important fungal phytopathogens. Major losses due to Colletotrichum are experienced in almost every crop worldwide, including nursery and landscape plants ...

  7. Lachancea Kurtzman (2003)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes the ascomycete yeast genus Lachancea and is to be published in "The Yeasts, A Taxonomic Study, 5th edition." The genus Lachancea was recently described following a multigene phylogenetic study and includes species previously assigned to the genera Kluyveromyces, Saccharomyces...

  8. Wickerhamiella van der Walt (1973)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes the ascomycetous yeast genus Wickerhamiella, which has five described species and has been defined from multigene deoxyribonucleic acid (DNA) sequence analysis. The species reproduce by multilateral budding but do not form hyphae or pseudohyphae. Asci typically form a single a...

  9. The transcription factor FgStuAp influences spore development, pathogenicity, and secondary metabolism in Fusarium graminearum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Members of the APSES family of fungal proteins regulate morphogenesis and virulence in ascomycetes. We deleted the FgStuA gene in Fusarium graminearum and demonstrate its involvement in several different processes. FgStuA is closely related to FoStuA in F. oxysporum and StuA in Aspergillus. Unlike F...

  10. Torulaspora Lindner (1904)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes the ascomycete yeast genus Torulaspora and is to be published in "The Yeasts, A Taxonomic Study," 5th edition. The genus Torulaspora is closely related to Zygosaccharomyces and Zygotorulaspora and has six described species. Many of the species are worldwide in distribution. ...

  11. Blastobotrys von Klopotek (1967)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes the anamorphic ascomycete genus Blastobotrys and is to be published in The Yeasts, a Taxonomic Study, 5th edition. The genus Blastobotrys, which represents the asexual state of the genus Trichomonascus, has been phylogenetically defined and has 21 assigned species. Blastobot...

  12. Detection and Identification of Decay Fungi in Spruce Wood by Restriction Fragment Length Polymorphism Analysis of Amplified Genes Encoding rRNA†

    PubMed Central

    Jasalavich, Claudia A.; Ostrofsky, Andrea; Jellison, Jody

    2000-01-01

    We have developed a DNA-based assay to reliably detect brown rot and white rot fungi in wood at different stages of decay. DNA, isolated by a series of CTAB (cetyltrimethylammonium bromide) and organic extractions, was amplified by the PCR using published universal primers and basidiomycete-specific primers derived from ribosomal DNA sequences. We surveyed 14 species of wood-decaying basidiomycetes (brown-rot and white-rot fungi), as well as 25 species of wood-inhabiting ascomycetes (pathogens, endophytes, and saprophytes). DNA was isolated from pure cultures of these fungi and also from spruce wood blocks colonized by individual isolates of wood decay basidiomycetes or wood-inhabiting ascomycetes. The primer pair ITS1-F (specific for higher fungi) and ITS4 (universal primer) amplified the internal transcribed spacer region from both ascomycetes and basidiomycetes from both pure culture and wood, as expected. The primer pair ITS1-F (specific for higher fungi) and ITS4-B (specific for basidiomycetes) was shown to reliably detect the presence of wood decay basidiomycetes in both pure culture and wood; ascomycetes were not detected by this primer pair. We detected the presence of decay fungi in wood by PCR before measurable weight loss had occurred to the wood. Basidiomycetes were identified to the species level by restriction fragment length polymorphisms of the internal transcribed spacer region. PMID:11055916

  13. What is Scirrhia?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ascomycete genus Scirrhia is presently treated as a member of the Dothideomycetidae, though uncertainty remains to which family it belongs in the Capnodiales within the Ascomycota. Recent collections on stems of a fern, Pteridium aquilinum (Dennstaedtiaceae) in Brazil, led to the discovery of a ...

  14. FAMILIES IN THE DIAPORTHALES: A NEW LOOK BASED ON LSU NUCLEAR RDNA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ascomycete order Diaporthales includes a number of plant pathogenic fungi, the most notorious of which is Cryphonectria parasitica, the chestnut blight fungus. Relationships among genera in the Diaporthales were evaluated as a basis for the recognition of families and to provide a taxonomic fra...

  15. New broad-spectrum resistance to septoria tritici blotch derived from synthetic hexaploid wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Septoria tritici blotch (STB), caused by the ascomycete Mycosphaerella graminicola, is one of the most devastating foliar diseases of wheat. We screened five synthetic hexaploid wheats (SHs), 13 wheat varieties that represent the differential set of cultivars and two susceptible checks with a global...

  16. Sex-linked phenotypic divergence in the hermaphrodite fungus Neurospora tetrasperma

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Here we present a study of the molecular phenotype linked to a large region of suppressed recombination (extending over ~ 7 Mbp and >1,500 genes) surrounding the mating-type (mat) locus of the filamentous ascomycete Neurospora tetrasperma. While the remainder of the genome is largely homoallelic, th...

  17. Genetic diversity in the Eucalyptus stem pathogen Teratosphaeria zuluensis

    E-print Network

    Genetic diversity in the Eucalyptus stem pathogen Teratosphaeria zuluensis M. N. CortinasA , I is one of the most important diseases affecting plantation-grown Eucalyptus trees. Little is known,MalawiandChinasuggestthatSouthAfricaismostprobablynotthecentreoforiginofthepathogenashaspreviously been suggested. Additional keywords: ascomycete, Eucalyptus stem canker, Kirramyces zuluensis

  18. Relationships among genera of the Saccharomycotina (Ascomycota) from multigene phylogenetic analysis of type species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phylogenetic relatedness among ascomycetous yeast genera (subphylum Saccharomycotina, phylum Ascomycota) has been uncertain. In the present study, type species of 70 currently recognized genera are compared from divergence in the nearly entire nuclear gene sequences for large subunit rRNA, small sub...

  19. Influence of host and geographic locale on the distribution of Colletotrichum cereale lineages

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Colletotrichum cereale is an ascomycete inhabitant of cool-season grasses of the Pooideae subfamily. The fungus has increased in frequency over the past decade as a destructive pathogen of Poa annua and Agrostis stolonifera cultivated as turfgrass. DNA fingerprinting has revealed two distinct C. c...

  20. Survival, germination, and growth of Epichloe typhina and significance of leaf wounds and insects in infection of orchardgrass

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Epichloë typhina, [choke] is an important stroma-producing endophytic ascomycete that is responsible for significant yield loss in orchardgrass seed production fields. Although infections are presumed to occur through leaves and stems, details of the infection process and conditions that favor leaf ...

  1. The potential role of water in spread of conidia of the Neotyphodium endophyte of Poa ampla

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Endophytes of the genus Neotyphodium are mutualistic fungi that colonize many cool season grasses. Neotyphodium endophytes are asexual but related to the ascomycete genus Epichloe. They do not produce obvious structures external to the host and for most of the life cycle are asymptomatic and system...

  2. Phaffomyces Y. Yamada, Higashi, S. Ando & Mikata (1997)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes the ascomycete yeast genus Phaffomyces and is to be published in "The Yeasts, A Taxonomic Study, 5th edition." The genus Phaffomyces was described for three species initially assigned to the genus Pichia, but these species proved quite distant from the type species of Pichia ...

  3. Scheffersomyces Kurtzman & M. Suzuki (2010)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes the ascomycete yeast genus Scheffersomyces and is to be published in "The Yeasts, A Taxonomic Study, 5th edition." The genus Scheffersomyces has three described species that were earlier assigned to the genus Pichia, but gene sequence analysis showed that the species, now rec...

  4. Nakazawaea Y. Yamada, Maeda & Mikata (1994)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes the ascomycete yeast genus Nakazawaea and is to be published in “The Yeasts, A Taxonomic Study,” 5th edition. The genus Nakazawaea was derived from the genus Pichia and its validity was established from a multigene phylogenetic analysis. The genus contains a single species, ...

  5. Kodamaea Y. Yamada, T. Suzuki, Matsuda & Mikata emend. Rosa, Lachance, Starmer, Barker, Bowles & Schlag-Edler (1999)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes the ascomycete yeast genus Kodamaea and is to be published in The Yeasts, A Taxonomic Study, 5th edition. The genus Kodamaea has five assigned species and all are associated with wood boring insects. Many of the species appear worldwide in distribution. One of the species, K...

  6. Three new anascosporic genera of the Saccharomycotina: Danielozyma gen. nov., Deakozyma gen. nov. and Middelhovenomyces gen. nov.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Three new non-ascosporic, ascomycetous yeast genera are proposed based on their isolation from currently described species and genera. Phylogenetic placement of the genera was determined from analysis of nuclear gene sequences for D1/D2 large subunit rRNA, small subunit rRNA, translation elongation...

  7. Characterization and complementation of an apparent FUM gene cluster deletion in Fusarium verticillioides.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The filamentous ascomycete Fusarium verticillioides is a worldwide pathogen of maize and produces the fumonisin mycotoxins. Contamination of maize kernels with fumonisin B1 (FB1) is of significant concern because of its causal role in equine leukoencephalomalacia, porcine pulmonary edema, liver and...

  8. Lipomyces Lodder & Kreger-van Rij (1952)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The chapter describes the ascomycete yeast genus Lipomyces and is to be published in “The Yeasts, A Taxonomic Study, 5th edition.” The genus Lipomyces has 16 known species, most of which are isolated exclusively from soil. Cultures of Lipomyces are generally slimy because of the copious production...

  9. Starmera Y. Yamada, Higashi, Ando & Mikata (1997)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes the ascomycete yeast genus Starmera and is to be published in "The Yeasts, A Taxonomic Study, 5th edition." The genus Starmera was described for three species initially assigned to the genus Pichia, but these species proved quite distant from the type species of Pichia when a...

  10. Application of a new approach for characterization and denomination of races of cucurbit powdery mildews – a case study on the Czech pathogen population

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Golovinomyces cichoracearum (Gc) and Podosphaera xanthii (Px) (Ascomycetes, Erysiphaceae) are the most important fungal species causing cucurbit powdery mildew (CPM), a serious disease of field and greenhouse cucurbits. Both species are highly variable, as indicated by the existence of large number ...

  11. Komagataella Y. Yamada, Matsuda, Maeda & Mikata (1995)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes the ascomycete yeast genus Komagataella and is to be published in "The Yeasts, A Taxonomic Study, 5th edition." The genus Komagataella was derived from the genus Pichia following a multigene phylogenetic analysis. The three known species assigned to Komagataella are indistin...

  12. Recognition of Yeast Species from Gene Sequence Comparisons

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This review discusses recognition of yeast species from gene sequence comparisons, which have been responsible for doubling the number of known yeasts over the past decade. The resolution provided by various single gene sequences is examined for both ascomycetous and basidiomycetous species, and th...

  13. Yarrowia van der Walt & von Arx (1980)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This book chapter describes the ascomycete yeast genus Yarrowia and is to be published in The Yeasts, A Taxonomic Study, 5th edition. The genus has just one described species, Y. lipolytica, and is commonly known by its asexual name Candida lipolytica. The species is widely distributed in name and...

  14. Ascosphaera subglobosa, a new species from North America associated with the solitary bee Megachile rotundata

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ascosphaera is a widespread ascomycetous genus of mostly obligate associates of bees. These fungi have diversified to exploit seemingly every possible substrate available in their bee-associated habitat, occurring as pathogens of the bees, or as saprotrophs on honey, cocoons, nesting materials, poll...

  15. CONIDIAL GERMINATION IN THE FILAMENTOUS FUNGUS FUSARIUM GRAMINEARUM

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ascomycetous fungus Fusarium graminearum is an important plant pathogen causing Fusarium head blight disease of wheat and barley. To understand early developmental stages of this organism, we followed the germination of macroconidia microscopically to understand the timing of key events. These e...

  16. Phylogeny and redescription of Dolabra nepheliae on rambutan and litchi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rambutan (Nephelium lappaceum L.) and lychee (Litchi chinensis Sonn.) are tropical trees in the Sapindaceae that produce delicious edible fruits and are increasingly cultivated in tropical areas. Recently these trees have been afflicted with a stem canker disease caused by the ascomycete Dolabra nep...

  17. Kingdom Fungi Some Basics ~80,000 species currently

    E-print Network

    Brown, Christopher A.

    are multicellular All have cell walls made of chitin Same stuff that makes up insect exoskeleton Plant cell walls material Form important symbiotic relationships with plants Cause diseases or infect organisms A source" A symbiosis (or mutualism) between a fungus and an algae or cyanobacteria Fungus nearly all ascomycetes, a few

  18. Release of Dimethylsulfide from Dimethylsulfoniopropionate by Plant-Associated Salt Marsh Fungi

    PubMed Central

    Bacic, M. K.; Newell, S. Y.; Yoch, D. C.

    1998-01-01

    The range of types of microbes with dimethylsulfoniopropionate (DMSP) lyase capability (enzymatic release of dimethylsulfide [DMS] from DMSP) has recently been expanded from bacteria and eukaryotic algae to include fungi (a species of the genus Fusarium [M. K. Bacic and D. C. Yoch, Appl. Environ. Microbiol. 64:106–111, 1998]). Fungi (especially ascomycetes) are the predominant decomposers of shoots of smooth cordgrass, the principal grass of Atlantic salt marshes of the United States. Since the high rates of release of DMS from smooth cordgrass marshes have a temporal peak that coincides with peak shoot death, we hypothesized that cordgrass fungi were involved in this DMS release. We tested seven species of the known smooth cordgrass ascomycetes and discovered that six of them exhibited DMSP lyase activity. We also tested two species of ascomycetes from other DMSP-containing plants, and both were DMSP lyase competent. For comparison, we tested 11 species of ascomycetes and mitosporic fungi from halophytes that do not contain DMSP; of these 11, only 3 were positive for DMSP lyase. A third group tested, marine oomycotes (four species of the genera Halophytophthora and Pythium, mostly from mangroves), showed no DMSP lyase activity. Two of the strains of fungi found to be positive for DMSP lyase also exhibited uptake of DMS, an apparently rare combination of capabilities. In conclusion, a strong correlation exists between a fungal decomposer’s ability to catabolize DMSP via the DMSP lyase pathway and the host plant’s production of DMSP as a secondary product. PMID:16349548

  19. Occultocarpon, a new monotypic genus of Gnomoniaceae on Alnus nepalensis from China

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new monotypic genus Occultocarpon and its species, O. ailaoshanense, was discovered on the bark of branches of Alnus nepalensis (Betulaceae) in Yunnan, China. A phylogeny based on three genes (LSU, rpb2, tef1-a) reveals that O. ailaoshanense belongs to the Gnomoniaceae (Diaporthales, Ascomycetes) ...

  20. Species identification of the causal agent of Eutypa dieback of grapevine in northeastern American and southeastern Canadian vineyards

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Eutypa dieback of Vitis (grape) is caused by the Ascomycete fungus Eutypa lata. The pathogen infects grapevine through wounds, and cause wood canker and dieback symptoms. E. lata has been identified in all major grape production areas in the world. The first report of Eutypa dieback from northeaster...

  1. Back to basics and beyond: increasing the level of resistance to Septoria tritici blotch in wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Septoria tritici blotch (STB), caused by the ascomycete Mycosphaerella graminicola (anamorph: Septoria tritici), is one of the most ubiquitous and important diseases of wheat worldwide. Losses to STB can range from 30 to 50% in disease-conducive climates. Little progress was made in increasing the...

  2. Cloning and sequence analysis of a mitochondrial gene cluster encoding cytochrome C oxidase subunit III from Trichoderma pseudokoningii.

    PubMed

    Wang, Tian-Hong; Wu, Zhi-Hong; Liu, Shi-Li; Huang, Wei

    2002-10-01

    A mitochondrial gene cluster encoding cytochrome c oxidase subunit III (COX3), an ORF (called ORF250) similar to NADH dehydrogenase subunit VI (ND6), ten tRNA molecules, partial rRNA small subunit and rRNA large subunit from Trichoderma pseudokoningii S38 was cloned and sequenced. These genes are tandemly clustered on the mitochondrial genome of Trichoderma pseudokoningii S38. Phylogenetic analysis showed that cytochrome C oxidase subunits III exhibited high degree of similarity to sequences from Hypocrea jecorina, Verticillium lecanii, Podospora anserine, Neurospora crassa and Magnaporthe grisea (99, 90, 84, 82 and 79% identity, respectively). Prediction of transmembrane helices revealed that COX3 was a transmembrane protein. Northern dot blot analysis showed that the cytochrome c oxidase subunits III gene we had cloned is actively transcribed in the T. pseudokoningii mitochondria. PMID:12592707

  3. Killer activity of yeasts isolated from natural environments against some medically important Candida species.

    PubMed

    Vadkertiová, Renata; Sláviková, Elena

    2007-01-01

    Twenty-five yeast cultures, mainly of human origin, belonging to four pathogenic yeast species--Candida albicans, Candida krusei, Candida parapsilosis, and Candida tropicalis were tested for their sensitivity to ten basidiomycetous and eleven ascomycetous yeast species isolated from the water and soil environments and from tree leaves. The best killer activity among basidiomycetous species was exhibited by Rhodotorula glutinis, and R. mucilaginosa. The other carotenoid producing species Cystofilobasidium capitatum, Sporobolomyces salmonicolor, and S. roseus were active only against about 40% of the tested strains and exhibited weak activity. The broadest killer activity among ascomycetous yeasts was shown by the strains Pichia anomala and Metschnikowia pulcherrima. The species Debaryomyces castellii, Debaryomyces hansenii, Hanseniaspora guilliermondii, Pichia membranifaciens, and Williopsis californica did not show any killer activity. The best killer activity exhibited the strains isolated from leafy material. The lowest activity pattern was found among strains originating from soil environment. PMID:17419188

  4. The most recent results on orchid mycorrhizal fungi in Hungary.

    PubMed

    Illyés, Z; Ouanphanivanh, Noémi; Rudnóy, Sz; Orczán, A K; Bratek, Z

    2010-01-01

    Symbionts and endophytes of Hungarian orchids were studied at diverse habitats. Mycobionts of roots and in situ germinated protocorms of 15 orchid species were identified by molecular methods. Four fungal groups could be distinguished from orchids living at diversely wet treeless habitats: Ceratobasidiaceae, Epulorhiza 1, Epulorhiza 2 and Sebacinaceae. While the groups Ceratobasidiaceae and Sebacinaceae were detected only at habitats with medium water supply, members of clade Epulorhiza occurred at all of the treeless study sites. These observations suggest that fungi belonging to the genus Epulorhiza are more tolerant of water-stress than the other investigated genera. An ascomycetous fungus from the family Pezizaceae could be identified from the roots of Orchis coriophora. Further Ascomycetes were identified at forest habitats. Tuber maculatum was detected from the roots of Epipactis helleborine and Cephalanthera damasonium, and Tuber excavatum from Epipactis microphylla. PMID:21565766

  5. Isolation and Characterization of a Novel Facultative Anaerobic Filamentous Fungus from Japanese Rice Field Soil

    PubMed Central

    Tonouchi, Akio

    2009-01-01

    A novel filamentous fungus strain designated RB-1 was isolated into pure culture from Japanese rice field soil through an anaerobic role tube technique. The strain is a mitosporic fungus that grows in both aerobic and strict anaerobic conditions using various mono-, di-, tri-, and polysaccharides with acetate and ethanol productions. The amount of acetate produced was higher than that of ethanol in both aerobic and anaerobic cultures. The characteristic verrucose or punctuate conidia of RB-1 closely resembled those of some strains of the genus Thermomyces, a thermophilic or mesophilic anamorphic ascomycete. However, based on phylogenetic analysis with the small subunit (SSU) and large subunit (LSU) rDNA sequences, RB-1 was characterized as a member of the class Lecanoromycetes of the phylum Ascomycota. Currently, RB-1 is designated as an anamorphic ascomycete and is phylogenetically considered an incertae sedis within the class Lecanoromycetes. PMID:20148171

  6. Production of extracellular ribonuclease by yeasts and yeastlike fungi, and its repression by orthophosphate in species of Cryptococcus and Tremella.

    PubMed Central

    Burt, W R; Cazin, J

    1976-01-01

    A strain of Cryptococcus laurentii and a haploid isolate of Tremella foliacea were shown to produce orthophosphate-repressible ribonuclease in liquid culture. Addition of as little as 1 mM K2HPO4, pH 7.0, completely repressed enzyme production by both fungi. The orthophosphate-repressible enzyme was not produced by other species of the two genera tested. These results, together with other findings, suggest a close phylogenetic relationship between Cryptococcus laurentii and Tremella foliacea. The ability of other yeasts and yeastlike fungi to hydrolyze ribonucleic acid in a solid test medium was assessed. Based on the limited number of organisms available for study, extracellular ribonuclease activity was found in species having close affinity to the Basidiomycetes and in yeasts classified in the ascomycetous genera, Endomycopsis, Hansenula, and Kluyveromyces. Other ascomycetous yeasts did not exhibit extracellular ribonuclease. PMID:1254561

  7. Assimilation of Unusual Carbon Compounds

    NASA Astrophysics Data System (ADS)

    Middelhoven, Wouter J.

    Yeast taxa traditionally are distinguished by growth tests on several sugars and organic acids. During the last decades it became apparent that many yeast species assimilate a much greater variety of naturally occurring carbon compounds as sole source of carbon and energy. These abilities are indicative of a greater role of yeasts in the carbon cycle than previously assumed. Especially in acidic soils and other habitats, yeasts may play a role in the degradation of carbon compounds. Such compounds include purines like uric acid and adenine, aliphatic amines, diamines and hydroxyamines, phenolics and other benzene compounds and polysaccharides. Assimilation of purines and amines is a feature of many ascomycetes and basidiomycetes. However, benzene compounds are degraded by only a few ascomycetous yeasts (e.g. the Stephanoascus/ Blastobotrys clade and black yeastlike fungi) but by many basidiomycetes, e.g. Filobasidiales, Trichosporonales, red yeasts producing ballistoconidia and related species, but not by Tremellales. Assimilation of polysaccharides is wide-spread among basidiomycetes

  8. Preliminary checklist of fungi of the Fernow Experimental Forest. Forest Service general technical report (Final)

    SciTech Connect

    Stephenson, S.L.; Kumar, A.; Bhatt, R.; Dubey, T.; Landolt, J.C.

    1994-01-01

    The report provides a checklist of fungi found on the Fernow Experimental Forest in West Virginia during 4 years of research and collecting by the authors. More than 500 fungi in seven major taxonomic groups (Acrasiomycetes, Myxomycetes, Chytridiomycetes, Oomycetes, Ascomycetes, Deuteromycetes, and Basidiomycetes) are listed alphabetically by genus and species. Also provided is a general description of the forest vegetation of the Fernow Experimental Forest.

  9. Palaeofibulus Gen. nov., a Clamp-Bearing Fungus from the Triassic of Antarctica

    E-print Network

    Osborn, Jeffrey M.; Taylor, Thomas N.; White, James F. Jr.

    1989-07-01

    sediments, was the first clamp-bearing fungus described. This fungus is regarded as a saprophytic basidiomycete based on its occurrence within the xylem of the coe-nopterid fern Zygopteris. Another clamp-bearing fungus from the Middle Pennsylvanian is Pa...-laeosclerotium Rothwell (1972). The presence of ascomycete-like reproductive structures (asci) in addition to subsequently identified clamp con-nections was the basis upon which Dennis (1976) suggested that this fungus represented an evo-lutionary intermediate between...

  10. Palaeofibulus gen. nov., a clamp-bearing fungus from the Triassic of Antarctica

    E-print Network

    Osborn, Jeffrey M.; Taylor, Thomas N.; White, James F. Jr.

    1989-01-05

    sediments, was the first clamp-bearing fungus described. This fungus is regarded as a saprophytic basidiomycete based on its occurrence within the xylem of the coe-nopterid fern Zygopteris. Another clamp-bearing fungus from the Middle Pennsylvanian is Pa...-laeosclerotium Rothwell (1972). The presence of ascomycete-like reproductive structures (asci) in addition to subsequently identified clamp con-nections was the basis upon which Dennis (1976) suggested that this fungus represented an evo-lutionary intermediate between...

  11. Spider, bacterial and fungal phospholipase D toxins make cyclic phosphate products.

    PubMed

    Lajoie, Daniel M; Cordes, Matthew H J

    2015-12-15

    Phospholipase D (PLD) toxins from sicariid spiders, which cause disease in mammals, were recently found to convert their primary substrates, sphingomyelin and lysophosphatidylcholine, to cyclic phospholipids. Here we show that two PLD toxins from pathogenic actinobacteria and ascomycete fungi, which share distant homology with the spider toxins, also generate cyclic phospholipids. This shared function supports divergent evolution of the PLD toxins from a common ancestor and suggests the importance of cyclic phospholipids in pathogenicity. PMID:26482933

  12. First isolation of the anamorph of Kazachstania heterogenica from a fatal infection in a primate host.

    PubMed

    Alvarez-Perez, Sergio; Mateos, Ana; Dominguez, Lucas; Martinez-Nevado, Eva; Rodriguez-Bertos, Antonio; Blanco, Jose L; Garcia, Marta E

    2012-02-01

    We describe the isolation of the anamorph of the ascomycetous yeast Kazachstania heterogenica from a fatal infection in a 2 year, 9-month-old female white-handed gibbon (Hylobates lar). The yeast was observed in histological sections (lung and intestine) and co-isolated with the bacterium Escherichia coli from different internal organs. This is the first report of the recovery of this yeast from a fatal infection in a primate host. PMID:21539504

  13. Structure Analysis Uncovers a Highly Diverse but Structurally Conserved Effector Family in Phytopathogenic Fungi.

    PubMed

    de Guillen, Karine; Ortiz-Vallejo, Diana; Gracy, Jérome; Fournier, Elisabeth; Kroj, Thomas; Padilla, André

    2015-10-01

    Phytopathogenic ascomycete fungi possess huge effector repertoires that are dominated by hundreds of sequence-unrelated small secreted proteins. The molecular function of these effectors and the evolutionary mechanisms that generate this tremendous number of singleton genes are largely unknown. To get a deeper understanding of fungal effectors, we determined by NMR spectroscopy the 3-dimensional structures of the Magnaporthe oryzae effectors AVR1-CO39 and AVR-Pia. Despite a lack of sequence similarity, both proteins have very similar 6 ?-sandwich structures that are stabilized in both cases by a disulfide bridge between 2 conserved cysteins located in similar positions of the proteins. Structural similarity searches revealed that AvrPiz-t, another effector from M. oryzae, and ToxB, an effector of the wheat tan spot pathogen Pyrenophora tritici-repentis have the same structures suggesting the existence of a family of sequence-unrelated but structurally conserved fungal effectors that we named MAX-effectors (Magnaporthe Avrs and ToxB like). Structure-informed pattern searches strengthened this hypothesis by identifying MAX-effector candidates in a broad range of ascomycete phytopathogens. Strong expansion of the MAX-effector family was detected in M. oryzae and M. grisea where they seem to be particularly important since they account for 5-10% of the effector repertoire and 50% of the cloned avirulence effectors. Expression analysis indicated that the majority of M. oryzae MAX-effectors are expressed specifically during early infection suggesting important functions during biotrophic host colonization. We hypothesize that the scenario observed for MAX-effectors can serve as a paradigm for ascomycete effector diversity and that the enormous number of sequence-unrelated ascomycete effectors may in fact belong to a restricted set of structurally conserved effector families. PMID:26506000

  14. Medicinal mushrooms: Towards a new horizon

    PubMed Central

    Ganeshpurkar, A.; Rai, G.; Jain, A. P.

    2010-01-01

    The arising awareness about functional food has created a boom in this new millennium. Mushrooms are widely consumed by the people due to their nutritive and medicinal properties. Belonging to taxonomic category of basidiomycetes or ascomycetes, these mushrooms possess antioxidant and antimicrobial properties. They are also one of the richest source of anticancer and immunomodulating agents. Thus these novel myochemicals from these mushrooms are the wave of future. PMID:22228952

  15. Structure Analysis Uncovers a Highly Diverse but Structurally Conserved Effector Family in Phytopathogenic Fungi

    PubMed Central

    Gracy, Jérome; Fournier, Elisabeth; Kroj, Thomas; Padilla, André

    2015-01-01

    Phytopathogenic ascomycete fungi possess huge effector repertoires that are dominated by hundreds of sequence-unrelated small secreted proteins. The molecular function of these effectors and the evolutionary mechanisms that generate this tremendous number of singleton genes are largely unknown. To get a deeper understanding of fungal effectors, we determined by NMR spectroscopy the 3-dimensional structures of the Magnaporthe oryzae effectors AVR1-CO39 and AVR-Pia. Despite a lack of sequence similarity, both proteins have very similar 6 ?-sandwich structures that are stabilized in both cases by a disulfide bridge between 2 conserved cysteins located in similar positions of the proteins. Structural similarity searches revealed that AvrPiz-t, another effector from M. oryzae, and ToxB, an effector of the wheat tan spot pathogen Pyrenophora tritici-repentis have the same structures suggesting the existence of a family of sequence-unrelated but structurally conserved fungal effectors that we named MAX-effectors (Magnaporthe Avrs and ToxB like). Structure-informed pattern searches strengthened this hypothesis by identifying MAX-effector candidates in a broad range of ascomycete phytopathogens. Strong expansion of the MAX-effector family was detected in M. oryzae and M. grisea where they seem to be particularly important since they account for 5–10% of the effector repertoire and 50% of the cloned avirulence effectors. Expression analysis indicated that the majority of M. oryzae MAX-effectors are expressed specifically during early infection suggesting important functions during biotrophic host colonization. We hypothesize that the scenario observed for MAX-effectors can serve as a paradigm for ascomycete effector diversity and that the enormous number of sequence-unrelated ascomycete effectors may in fact belong to a restricted set of structurally conserved effector families. PMID:26506000

  16. Long-term changes in soil microbial communities during primary succession

    E-print Network

    Cutler, Nick A.; Chaput, Dominique L.; van der Gast, Christopher J.

    2013-12-06

    succession has been observed before: Osana and Trofymow (2012), for 518 example, reported succession in saprotrophic fungi living in moss, but this process has not, 519 to our knowledge, been observed on a timescale of centuries. 520 521 20... mycorrhizal associations over time (Bardgett et al., 2005). Jumpponen (2003) hypothesised 530 that early successional communities would be dominated by saprotrophic Ascomycetes and 531 Basidiomycetes, whereas fungal communities on older substrates would...

  17. Capnodiaceae.

    PubMed

    Chomnunti, Putarak; Schoch, Conrad L; Aguirre-Hudson, Begońa; Ko-Ko, Thida W; Hongsanan, Sinang; Jones, E B Gareth; Kodsueb, Rampai; Phookamsak, Rungtiwa; Chukeatirote, Ekachai; Bahkali, Ali H; Hyde, Kevin D

    2011-12-01

    In this paper we revisit the Capnodiaceae with notes on selected genera. Type specimens of the ascomycetous genera Aithaloderma, Anopeltis, Callebaea, Capnodaria, Echinothecium, Phragmocapnias and Scorias were re-examined, described and illustrated. Leptoxyphium is anamorphic Capnodiaceae and Polychaeton is a legitimate and earlier name for Capnodium, but in order to maintain nomenclatural stability we propose that the teleomorphic name should be conisdered for the approved lists of names currently in preparation for fungi. Notes are provided on the ascomycetous genus Scoriadopsis. However, we were unable to locate the type of this genus during the time frame of this study. The ascomycetous genera Aithaloderma, Ceramoclasteropsis, Hyaloscolecostroma and Trichomerium are excluded from Capnodiaceae on the basis of having ascostromata and trans-septate hyaline ascospores and should be accommodated in Chaetothyriaceae. Callebaea is excluded as the ascomata are thyriothecia and the genus is placed in Micropeltidaceae. Echinothecium is excluded as synonym of Sphaerellothecium and is transferred to Mycosphaerellaceae. The type specimen of Capnophaeum is lost and this should be considered as a doubtful genus. The coelomycetous Microxiphium is polyphyletic, while the status of Fumiglobus, Polychaetella and Tripospermum is unclear. Fourteen new collections of sooty moulds made in Thailand were isolated and sequenced. The nuclear large and small rDNA was partially sequenced and compared in a phylogeny used to build a more complete understanding of the relationships of genera in Capnodiaceae. Four new species are described and illustrated, while Phragmocapnias and Scorias are epitypified with fresh collections. PMID:22737101

  18. Germinal Center Kinases SmKIN3 and SmKIN24 Are Associated with the Sordaria macrospora Striatin-Interacting Phosphatase and Kinase (STRIPAK) Complex

    PubMed Central

    Frey, Stefan; Reschka, Eva J.; Pöggeler, Stefanie

    2015-01-01

    The striatin-interacting phosphatase and kinase (STRIPAK) complex is composed of striatin, protein phosphatase PP2A and protein kinases that regulate development in animals and fungi. In the filamentous ascomycete Sordaria macrospora, it is required for fruiting-body development and cell fusion. Here, we report on the presence and function of STRIPAK-associated kinases in ascomycetes. Using the mammalian germinal center kinases (GCKs) MST4, STK24, STK25 and MINK1 as query, we identified the two putative homologs SmKIN3 and SmKIN24 in S. macrospora. A BLASTP search revealed that both kinases are conserved among filamentous ascomycetes. The physical interaction of the striatin homolog PRO11 with SmKIN3 and SmKIN24 were verified by yeast two-hybrid (Y2H) interaction studies and for SmKIN3 by co-Immunoprecipitation (co-IP). In vivo localization found that both kinases were present at the septa and deletion of both Smkin3 and Smkin24 led to abnormal septum distribution. While deletion of Smkin3 caused larger distances between adjacent septa and increased aerial hyphae, deletion of Smkin24 led to closer spacing of septa and to sterility. Although phenotypically distinct, both kinases appear to function independently because the double-knockout strain ?Smkin3/?Smkin24 displayed the combined phenotypes of each single-deletion strain. PMID:26418262

  19. Mycological evidence of coprophagy from the feces of an Alaskan Late Glacial mammoth

    NASA Astrophysics Data System (ADS)

    van Geel, Bas; Guthrie, R. Dale; Altmann, Jens G.; Broekens, Peter; Bull, Ian D.; Gill, Fiona L.; Jansen, Boris; Nieman, Aline M.; Gravendeel, Barbara

    2011-08-01

    Dung from a mammoth was preserved under frozen conditions in Alaska. The mammoth lived during the early part of the Late Glacial interstadial (ca 12,300 BP). Microfossils, macroremains and ancient DNA from the dung were studied and the chemical composition was determined to reconstruct both the paleoenvironment and paleobiology of this mammoth. Pollen spectra are dominated by Poaceae, Artemisia and other light-demanding taxa, indicating an open, treeless landscape ('mammoth steppe'). Fruits and seeds support this conclusion. The dung consists mainly of cyperaceous stems and leaves, with a minor component of vegetative remains of Poaceae. Analyses of fragments of the plastid rbcL gene and trnL intron and nrITS1 region, amplified from DNA extracted from the dung, supplemented the microscopic identifications. Many fruit bodies with ascospores of the coprophilous fungus Podospora conica were found inside the dung ball, indicating that the mammoth had eaten dung. The absence of bile acids points to mammoth dung. This is the second time that evidence for coprophagy of mammoths has been derived from the presence of fruit bodies of coprophilous fungi in frozen dung. Coprophagy might well have been a common habit of mammoths. Therefore, we strongly recommend that particular attention should be given to fungal remains in future fossil dung studies.

  20. [Cloning and characterization of glyceraldehyde-3-phosphate dehydrogenase gene from Chaetomium globosum].

    PubMed

    Liu, Zhi-Hua; Yang, Qian

    2005-12-01

    The amino acid sequence of Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) gene from Neurospora crassa (XP-327967) and Colletotrichum lindemuthianu (P35143) were subjected to local tBlastn searching against the ESTs local datebase of Chaetomium globosum. The full length cDNA sequence of 1240bp encoding GAPDH gene with an open reading frame of 1014bp and encoding 337 amino acids was obtained. The protein molecular weight was 36.1kD. The DNA sequence of GAPDH gene was obtained through PCR amplification with specific primers of cDNA 5' and 3' untranslated region. The analysis of DNA sequence indicated that GAPDH gene have 3 exons and 2 introns. The BlastP analysis revealed that amino acids sequence of GAPDH gene from C. globosum shared 95% high similarity with Podospora anserin and 87% low similarty with Aspergillus oryzae. A transgenic yeast harboring C. globosum GAPDH was generated under the control of a constitutively expressed GAL promoter. The results from biofunctional analyses of GAPDH yeast transformants showed that GAPDH yeast transformants had significantly higher resistance to Na2 CO3 and heat stresses. The cDNA, DNA and deduced amino acid sequence of GAPDH gene were accepted by GenBank (accession numbers: AY522719, AY593253, AAS01412). PMID:16496697

  1. Microsatellites identify depredated waterfowl remains from glaucous gull stomachs

    USGS Publications Warehouse

    Scribner, K.T.; Bowman, T.D.

    1998-01-01

    Prey remains can provide valuable sources of information regarding causes of predation and the species composition of a predator's diet. Unfortunately, the highly degraded state of many prey samples from gastrointestinal tracts often precludes unambiguous identification. We describe a procedure by which PCR amplification of taxonomically informative microsatellite loci were used to identify species of waterfowl predated by glaucous gulls (Larus hyperboreus). We found that one microsatellite locus unambiguously distinguished between species of the subfamily Anserinae (whistling ducks, geese and swans) and those of the subfamily Anatidae (all other ducks). An additional locus distinguished the remains of all geese and swan species known to nest on the Yukon-Kuskokwim delta in western Alaska. The study focused on two waterfowl species which have experienced precipitous declines in population numbers: emperor geese (Chen canagica) and spectacled eiders (Somateria fischeri). No evidence of predation on spectacled eiders was observed. Twenty-six percent of all glaucous gull stomachs examined contained the remains of juvenile emperor geese.

  2. Communities of Endophytic Sebacinales Associated with Roots of Herbaceous Plants in Agricultural and Grassland Ecosystems Are Dominated by Serendipita herbamans sp. nov

    PubMed Central

    Riess, Kai; Oberwinkler, Franz; Bauer, Robert; Garnica, Sigisfredo

    2014-01-01

    Endophytic fungi are known to be commonly associated with herbaceous plants, however, there are few studies focusing on their occurrence and distribution in plant roots from ecosystems with different land uses. To explore the phylogenetic diversity and community structure of Sebacinales endophytes from agricultural and grassland habitats under different land uses, we analysed the roots of herbaceous plants using strain isolation, polymerase chain reaction (PCR), transmission electron microscopy (TEM) and co-cultivation experiments. A new sebacinoid strain named Serendipita herbamans belonging to Sebacinales group B was isolated from the roots of Bistorta vivipara, which is characterized by colourless monilioid cells (chlamydospores) that become yellow with age. This species was very common and widely distributed in association with a broad spectrum of herbaceous plant families in diverse habitats, independent of land use type. Ultrastructurally, the presence of S. herbamans was detected in the cortical cells of Plantago media, Potentilla anserina and Triticum aestivum. In addition, 13 few frequent molecular operational taxonomic units (MOTUs) or species were found across agricultural and grassland habitats, which did not exhibit a distinctive phylogenetic structure. Laboratory-based assays indicate that S. herbamans has the ability to colonize fine roots and stimulate plant growth. Although endophytic Sebacinales are widely distributed across agricultural and grassland habitats, TEM and nested PCR analyses reinforce the observation that these microorganisms are present in low quantity in plant roots, with no evidence of host specificity. PMID:24743185

  3. DNA barcoding and phylogenetic relationships in Anatidae.

    PubMed

    Huang, Zuhao; Yang, Chengzhong; Ke, Dianhua

    2016-03-01

    Mitochondrial cytochrome c oxidase subunit I (COI) has been used as a powerful marker in a variety of phylogenetic studies. According to studies of bird species, the 694-bp sequence of the mitochondrial gene encoding COI is extremely useful for species identification and phylogeny. In the present study, we analyzed the COI barcodes of 79 species from 26 genera belonging to the Anatidae family. Sixty-six species (83.54%) of the species were identified correctly from their DNA barcodes. The remaining 13 species shared barcodes sequences with closely related species. Kimura two-parameter (K2P) distances were calculated between barcodes. The average genetic distance between species was 41 times higher compared to the average genetic distance within species. Neighbor-joining method was used to construct a phylogenetic tree, which grouped all of the genera into three divergent clades. Dendrocygna and Nomonyx?+?Oxyura were identified as early offshoots of the Anatidae. All the remaining taxa fell into two clades that correspond to the two subfamilies Anserinae and Anatiane. Based on our results, DNA barcoding is an effective molecular tool for Anatidae species identification and phylogenetic inference. PMID:24938090

  4. Essential Gene Discovery in the Basidiomycete Cryptococcus neoformans for Antifungal Drug Target Prioritization

    PubMed Central

    Ianiri, Giuseppe

    2015-01-01

    ABSTRACT Fungal diseases represent a major burden to health care globally. As with other pathogenic microbes, there is a limited number of agents suitable for use in treating fungal diseases, and resistance to these agents can develop rapidly. Cryptococcus neoformans is a basidiomycete fungus that causes cryptococcosis worldwide in both immunocompromised and healthy individuals. As a basidiomycete, it diverged from other common pathogenic or model ascomycete fungi more than 500 million years ago. Here, we report C. neoformans genes that are essential for viability as identified through forward and reverse genetic approaches, using an engineered diploid strain and genetic segregation after meiosis. The forward genetic approach generated random insertional mutants in the diploid strain, the induction of meiosis and sporulation, and selection for haploid cells with counterselection of the insertion event. More than 2,500 mutants were analyzed, and transfer DNA (T-DNA) insertions in several genes required for viability were identified. The genes include those encoding the thioredoxin reductase (Trr1), a ribosome assembly factor (Rsa4), an mRNA-capping component (Cet1), and others. For targeted gene replacement, the C. neoformans homologs of 35 genes required for viability in ascomycete fungi were disrupted, meiosis and sporulation were induced, and haploid progeny were evaluated for their ability to grow on selective media. Twenty-one (60%) were found to be required for viability in C. neoformans. These genes are involved in mitochondrial translation, ergosterol biosynthesis, and RNA-related functions. The heterozygous diploid mutants were evaluated for haploinsufficiency on a number of perturbing agents and drugs, revealing phenotypes due to the loss of one copy of an essential gene in C. neoformans. This study expands the knowledge of the essential genes in fungi using a basidiomycete as a model organism. Genes that have no mammalian homologs and are essential in both Cryptococcus and ascomycete human pathogens would be ideal for the development of antifungal drugs with broad-spectrum activity. PMID:25827419

  5. Genomic Mechanisms Accounting for the Adaptation to Parasitism in Nematode-Trapping Fungi

    PubMed Central

    Meerupati, Tejashwari; Andersson, Karl-Magnus; Friman, Eva; Kumar, Dharmendra; Tunlid, Anders; Ahrén, Dag

    2013-01-01

    Orbiliomycetes is one of the earliest diverging branches of the filamentous ascomycetes. The class contains nematode-trapping fungi that form unique infection structures, called traps, to capture and kill free-living nematodes. The traps have evolved differently along several lineages and include adhesive traps (knobs, nets or branches) and constricting rings. We show, by genome sequencing of the knob-forming species Monacrosporium haptotylum and comparison with the net-forming species Arthrobotrys oligospora, that two genomic mechanisms are likely to have been important for the adaptation to parasitism in these fungi. Firstly, the expansion of protein domain families and the large number of species-specific genes indicated that gene duplication followed by functional diversification had a major role in the evolution of the nematode-trapping fungi. Gene expression indicated that many of these genes are important for pathogenicity. Secondly, gene expression of orthologs between the two fungi during infection indicated that differential regulation was an important mechanism for the evolution of parasitism in nematode-trapping fungi. Many of the highly expressed and highly upregulated M. haptotylum transcripts during the early stages of nematode infection were species-specific and encoded small secreted proteins (SSPs) that were affected by repeat-induced point mutations (RIP). An active RIP mechanism was revealed by lack of repeats, dinucleotide bias in repeats and genes, low proportion of recent gene duplicates, and reduction of recent gene family expansions. The high expression and rapid divergence of SSPs indicate a striking similarity in the infection mechanisms of nematode-trapping fungi and plant and insect pathogens from the crown groups of the filamentous ascomycetes (Pezizomycotina). The patterns of gene family expansions in the nematode-trapping fungi were more similar to plant pathogens than to insect and animal pathogens. The observation of RIP activity in the Orbiliomycetes suggested that this mechanism was present early in the evolution of the filamentous ascomycetes. PMID:24244185

  6. [Comparison of the fungal complexes of the Japanese scallop Mizuhopecten yessoensis (Jay, 1856) from different areas of the Peter the Great Bay, Sea of Japan].

    PubMed

    Borzykh, O G; Zvereva, L V

    2014-01-01

    Mycological investigation of the Japanese scallop Mizuhopecten yessoensis (Jay) (Bivalvia) collected in different areas of the Peter the Great Bay, Sea of Japan, was carried out. A total of 72 species of filamentous fungi belonging to 30 genera of ascomycetes, anamorphous fungi, and zygomycetes was isolated from the internal organs of the scallop. The species.diversity of mycelial fungi in the internal organs, especially of members of the generaAspergillus, Penicillium, Cladosporium, and Chaetomium, was found to increase in polluted coastal waters. PMID:25844471

  7. Arxula adeninivorans (Blastobotrys adeninivorans) — A Dimorphic Yeast of Great Biotechnological Potential

    NASA Astrophysics Data System (ADS)

    Böer, Erik; Steinborn, Gerhard; Florschütz, Kristina; Körner, Martina; Gellissen, Gerd; Kunze, Gotthard

    The dimorphic ascomycetous yeast Arxula adeninivorans exhibits some unusual properties. Being a thermo- and halotolerant species it is able to assimilate and ferment many compounds as sole carbon and/or nitrogen source. It utilises n-alkanes and is capable of degrading starch. Due to these unusual biochemical properties A. adeninivorans can be exploited as a gene donor for the production of enzymes with attractive biotechnological characteristics. Examples of A. adeninivorans-derived genes that are overexpressed include the ALIP1 gene encoding a secretory lipase, the AINV encoding invertase, the AXDH encoding xylitol dehydrogenase and the APHY encoding a secretory phosphatase with phytase activity.

  8. PKC1, encoding a protein kinase C, and FAT1, encoding a fatty acid transporter protein, are neighbors in Cochliobolus heterostrophus.

    PubMed

    Oeser, B

    1998-08-15

    A protein kinase C gene (PKC1) and adjacent DNA of the filamentous ascomycete Cochliobolus heterostrophus was cloned and sequenced. The deduced amino acid sequence of PKC1 shows high homology to PKCs of other filamentous fungi and all define a new subgroup of PKCs. All attempts to disrupt PKC1 failed, suggesting, but not proving, that disruption of PKC1 function is lethal. About 1 kb 3' of PKC1 is FAT1 encoding a putative bifunctional fatty acid transporter/very-long-chain acyl-CoA synthetase. PMID:9742699

  9. Parallels in Amphibian and Bat Declines from Pathogenic Fungi

    PubMed Central

    Eskew, Evan A.

    2013-01-01

    Pathogenic fungi have substantial effects on global biodiversity, and 2 emerging pathogenic species—the chytridiomycete Batrachochytrium dendrobatidis, which causes chytridiomycosis in amphibians, and the ascomycete Geomyces destructans, which causes white-nose syndrome in hibernating bats—are implicated in the widespread decline of their vertebrate hosts. We synthesized current knowledge for chytridiomycosis and white-nose syndrome regarding disease emergence, environmental reservoirs, life history characteristics of the host, and host–pathogen interactions. We found striking similarities between these aspects of chytridiomycosis and white-nose syndrome, and the research that we review and propose should help guide management of future emerging fungal diseases. PMID:23622255

  10. Parallels in amphibian and bat declines from pathogenic fungi.

    PubMed

    Eskew, Evan A; Todd, Brian D

    2013-03-01

    Pathogenic fungi have substantial effects on global biodiversity, and 2 emerging pathogenic species-the chytridiomycete Batrachochytrium dendrobatidis, which causes chytridiomycosis in amphibians, and the ascomycete Geomyces destructans, which causes white-nose syndrome in hibernating bats-are implicated in the widespread decline of their vertebrate hosts. We synthesized current knowledge for chytridiomycosis and white-nose syndrome regarding disease emergence, environmental reservoirs, life history characteristics of the host, and host-pathogen interactions. We found striking similarities between these aspects of chytridiomycosis and white-nose syndrome, and the research that we review and propose should help guide management of future emerging fungal diseases. PMID:23622255

  11. Phylogenetic relationships among species of Williopsis and Saturnospora gen. nov. as determined from partial rRNA sequences.

    PubMed

    Liu, Z W; Kurtzman, C P

    1991-07-01

    Phylogenetic relationships among those yeast species that form saturn-shaped ascospores and which are assigned to the genera Williopsis and Pichia were estimated from their extent of nucleotide sequence divergence in three regions of ribosomal RNA. The Pichia species (P. dispora, P. saitoi, P. zaruensis and P. sp. nov.) are a closely clustered group only distantly related to Williopsis, and it is proposed that they be reassigned to Saturnospora gen. nov. The extent of divergence among Williopsis species (W. californica, W. mucosa, W. pratensis, W. saturnus and W. sp. nov.) is greater than that previously observed within other ascomycetous yeast genera. PMID:1796804

  12. A?-42 lowering agents from the marine-derived fungus Dichotomomyces cejpii.

    PubMed

    Harms, Henrik; Kehraus, Stefan; Nesaei-Mosaferan, Damun; Hufendieck, Peter; Meijer, Laurent; König, Gabriele M

    2015-12-01

    The ascomycete Dichotomomyces cejpii was isolated from the marine sponge Callyspongia cf. C. flammea. Three new steroids (1-3), two of which are present as glycosides, with an untypical pattern of carbon-carbon double bounds, were obtained from fungal extracts, as well as the known xanthocillin X dimethyl ether (4). Compounds 2 and 4 were evaluated in an Alzheimer's disease cellular assay and found capable of preventing the enhanced production of amyloid ?-42 in Aftin-5 treated cells. A?-42 lowering agents are considered as candidates for the treatment of neurodegenerative Alzheimer's disease. PMID:26440473

  13. Endolithic biofilms: a model for extraterrestrial ecological niches?

    NASA Astrophysics Data System (ADS)

    Pohl, Wolfhart; Hoppert, Michael; Flies, Christine; Gunzl, Bettina; Ruppert, Hans; Schneider, Juergen

    1999-12-01

    In natural ecosystems, bacteria, unicellular algae, filamentous and yeast-like fungi are often organized in thin films attached to or entrenched in substrata such as surfaces of solid rocks, minerals or larger organisms. Frequently the formation of a biofilm is the most successful survival strategy. Especially within endolithic biofilms micro-organisms actively create a safe niche to avoid extreme and thus harmful environmental conditions such as electromagnetic radiation, mechanical abrasion, water and temperature stress and hazardous chemical agents. Exemplary survival strategies are presented for bacteria, ascomycetes and green algae. On substrata without organic carbon sources, biofilms are composed of chemolithotrophic or phototrophic primary producers and heterotrophic organisms (including destruents).

  14. Detection of presumptive mycoparasites associated with Entomophaga maimaiga resting spores in forest soils.

    PubMed

    Castrillo, Louela A; Hajek, Ann E

    2015-01-01

    The fungal pathogen Entomophaga maimaiga can provide high levels of control of the gypsy moth, Lymantria dispar, an important forest defoliator. This fungus persists in the soil as resting spores and occurs naturally throughout many areas where gypsy moth is established. Studies on the spatial dynamics of gypsy moth population have shown high variability in infection levels, and one possible biological factor could be the variable persistence of E. maimaiga resting spores in the soil due to attacks by mycoparasites. We surveyed presumptive mycoparasites associated with parasitized E. maimaiga resting spores using baiting and molecular techniques and identified an ascomycete (Pochonia sp.) and oomycetes (Pythium spp.). PMID:25433313

  15. First radiobiological results of LDEF-1 experiment A0015 with Arabidopsis seed embryos and Sordaria fungus spores

    NASA Astrophysics Data System (ADS)

    Zimmermann, M. W.; Gartenbach, K. E.; Kranz, A. R.

    1994-10-01

    This article highlights the first results of investigations on the general vitality and damage endpoints caused by cosmic ionizing radiation in dry, dormant plant seeds of the crucifer plant Arabidopsis thaliana (L.) Hennh. and the ascomycete Sordaria fimicola after 69 month stay in space. Wild-type and mutant gene marker lines were included in Free Flyer Biostack containers and exposed on earth and side tray of the LDEF-1 satellite. The damage in biological endpoints observed in the seeds increased in the side tray sample compared to the earth tray sample. For the ascospores we found different effects depending on the biological endpoints investigated for both expositions.

  16. Enzymatic activity of endophytic fungi of six native seedling species from Doi Suthep-Pui National Park, Thailand.

    PubMed

    Lumyong, Saisamorn; Lumyong, Pipob; McKenzie, Eric H C; Hyde, Kevin D

    2002-12-01

    Endophytic fungi were isolated from the stems, petioles, midribs, and leaves of seedlings of six native tree species collected from Doi Suthep-Pui National Park, Thailand. Endophytes were isolated from all tissue samples investigated, and taxa included five ascomycetes, eight anamorphic taxa, and numerous sterile mycelia. Twenty-six strains were tested for their ability to produce cellulase, mannanase, proteinase, and xylanase. The ability to produce these enzymes was distributed amongst the strains tested. Rainforest seedlings supported a diverse array of endophytes that have a wide range of enzymatic activities. The implication of enzyme production in relation to lifestyle abilities of the endophytes is discussed. PMID:12619825

  17. Fungal diversity on fallen leaves of Ficus in northern Thailand.

    PubMed

    Wang, Hong-Kai; Hyde, Kevin D; Soytong, Kasem; Lin, Fu-Cheng

    2008-10-01

    Fallen leaves of Ficus altissima, F. virens, F. benjamina, F. fistulosa and F. semicordata, were collected in Chiang Mai Province in northern Thailand and examined for fungi. Eighty taxa were identified, comprising 56 anamorphic taxa, 23 ascomycetes and 1 basidiomycete. Common fungal species occurring on five host species with high frequency of occurrence were Beltraniella nilgirica, Lasiodiplodia theobromae, Ophioceras leptosporum, Periconia byssoides and Septonema harknessi. Colletotrichum and Stachybotrys were also common genera. The leaves of different Ficus species supported diverse fungal taxa, and the fungal assemblages on the different hosts showed varying overlap. The fungal diversity of saprobes at the host species level is discussed. PMID:18837113

  18. Zygomycetes in Vesicular Basanites from Vesteris Seamount, Greenland Basin--A New Type of Cryptoendolithic Fungi.

    PubMed

    Ivarsson, Magnus; Peckmann, Jörn; Tehler, Anders; Broman, Curt; Bach, Wolfgang; Behrens, Katharina; Reitner, Joachim; Böttcher, Michael E; Norbäck Ivarsson, Lena

    2015-01-01

    Fungi have been recognized as a frequent colonizer of subseafloor basalt but a substantial understanding of their abundance, diversity and ecological role in this environment is still lacking. Here we report fossilized cryptoendolithic fungal communities represented by mainly Zygomycetes and minor Ascomycetes in vesicles of dredged volcanic rocks (basanites) from the Vesteris Seamount in the Greenland Basin. Zygomycetes had not been reported from subseafloor basalt previously. Different stages in zygospore formation are documented in the studied samples, representing a reproduction cycle. Spore structures of both Zygomycetes and Ascomycetes are mineralized by romanechite-like Mn oxide phases, indicating an involvement in Mn(II) oxidation to form Mn(III,VI) oxides. Zygospores still exhibit a core of carbonaceous matter due to their resistance to degradation. The fungi are closely associated with fossiliferous marine sediments that have been introduced into the vesicles. At the contact to sediment infillings, fungi produced haustoria that penetrated and scavenged on the remains of fragmented marine organisms. It is most likely that such marine debris is the main carbon source for fungi in shallow volcanic rocks, which favored the establishment of vital colonies. PMID:26181773

  19. Evidence for negative-strand RNA virus infection in fungi.

    PubMed

    Kondo, Hideki; Chiba, Sotaro; Toyoda, Kazuhiro; Suzuki, Nobuhiro

    2013-01-20

    Fungal viruses comprise two groups: a major group of five families with double-stranded RNA genomes and a minor group with positive-sense single-stranded (ss)RNA genomes. Although many fungal viruses have been identified, no negative-stranded (-)ssRNA mycoviruses have been reported. Here we present two lines of evidence suggesting the presence of (-)ssRNA viruses in filamentous fungi based on an exhaustive search using extant (-)ssRNA viruses as queries. This revealed (-)ssRNA virus L protein-like sequences in the genome of a phytopathogenic obligate ascomycete, Erysiphe pisi. A similar search for (-)ssRNA viruses in fungal transcriptome shotgun assembly libraries demonstrated that two independent libraries from Sclerotinia homoeocarpa, another phytopathogenic ascomycete, contained several sequences considered to correspond to the entire mononegavirus L gene and likely originating from an infecting (-)ssRNA virus. These results provide strong evidence for both ancient and extant (-)ssRNA virus infections in fungi. PMID:23099204

  20. The conserved global regulator VeA is necessary for symptom production and mycotoxin synthesis in maize seedlings by Fusarium verticillioides

    PubMed Central

    Myung, K.; Zitomer, N. C.; Duvall, M.; Glenn, A. E.; Riley, R. T.; Calvo, A. M.

    2011-01-01

    The veA or velvet gene is necessary for biosynthesis of mycotoxins and other secondary metabolites in Aspergillus species. In addition, veA has also been demonstrated to be necessary for normal seed colonization in Aspergillus flavus and Aspergillus parasiticus. The present study shows that veA homologues are broadly distributed in fungi, particularly in Ascomycetes. The Fusarium verticillioides veA orthologue, FvVE1, is also required for the synthesis of several secondary metabolites, including fumonisin and fusarins. This study also shows that maize plants grown from seeds inoculated with FvVE1 deletion mutants did not show disease symptoms, while plants grown from seeds inoculated with the F. verticillioides wildtype and complementation strains clearly showed disease symptoms under the same experimental conditions. In this latter case, the presence of lesions coincided with accumulation of fumonisins in the plant tissues, and only these plant tissues had elevated levels of sphingoid bases and their 1-phosphate derivatives, indicating inhibition of ceramide synthase and disruption of sphingolipid metabolism. The results strongly suggest that FvVE1 is necessary for pathogenicity by F. verticillioides against maize seedlings. The conservation of veA homologues among ascomycetes suggests that veA could play a pivotal role in regulating secondary metabolism and associated pathogenicity in other fungi. PMID:22247572

  1. Zygomycetes in Vesicular Basanites from Vesteris Seamount, Greenland Basin – A New Type of Cryptoendolithic Fungi

    PubMed Central

    Ivarsson, Magnus; Peckmann, Jörn; Tehler, Anders; Broman, Curt; Bach, Wolfgang; Behrens, Katharina; Reitner, Joachim; Böttcher, Michael E.; Norbäck Ivarsson, Lena

    2015-01-01

    Fungi have been recognized as a frequent colonizer of subseafloor basalt but a substantial understanding of their abundance, diversity and ecological role in this environment is still lacking. Here we report fossilized cryptoendolithic fungal communities represented by mainly Zygomycetes and minor Ascomycetes in vesicles of dredged volcanic rocks (basanites) from the Vesteris Seamount in the Greenland Basin. Zygomycetes had not been reported from subseafloor basalt previously. Different stages in zygospore formation are documented in the studied samples, representing a reproduction cycle. Spore structures of both Zygomycetes and Ascomycetes are mineralized by romanechite-like Mn oxide phases, indicating an involvement in Mn(II) oxidation to form Mn(III,VI) oxides. Zygospores still exhibit a core of carbonaceous matter due to their resistance to degradation. The fungi are closely associated with fossiliferous marine sediments that have been introduced into the vesicles. At the contact to sediment infillings, fungi produced haustoria that penetrated and scavenged on the remains of fragmented marine organisms. It is most likely that such marine debris is the main carbon source for fungi in shallow volcanic rocks, which favored the establishment of vital colonies. PMID:26181773

  2. Silencing of Kex2 significantly diminishes the virulence of Cryphonectria parasitica.

    PubMed

    Jacob-Wilk, Debora; Turina, Massimo; Kazmierczak, Pam; Van Alfen, Neal K

    2009-02-01

    Cryphonectria parasitica is the causal agent of chestnut blight. Infection of this ascomycete with Cryphonectria hypovirus 1 (CHV1) results in reduction of virulence and sporulation of the fungus. The virus affects fungal gene expression and several of the CHV1 downregulated genes encode secreted proteins that contain consensus Kex2 processing signals. Additionally, CHV1 has been shown to colocalize in infected cells primarily with fungal trans-Golgi network vesicles containing the Kex2 protease. We report here the cloning, analysis, and possible role of the C. parasitica Kex2 gene (CpKex2). CpKex2 gene sequence analysis showed high similarity to other ascomycete kexin-like proteins. Southern blot analyses of CpKex2 showed a single copy of this gene in the fungal genome. In order to monitor the expression and evaluate the function of CpKex2, antibodies were raised against expressed protein and Kex2-silenced mutants were generated. Western blots indicate that the Kex2 protein was constitutively expressed. Growth rate of the fungus was not significantly affected in Kex2-silenced strains; however, these strains showed reduced virulence, reduced sexual and asexual sporulation, and reductions in mating and fertility. The reduced virulence was correlated with reduced Kex2 enzymatic activity and reduced relative mRNA transcript levels as measured by real time reverse-transcriptase polymerase chain reaction. These results suggest that secreted proteins processed by Kex2 are important in fungal development and virulence. PMID:19132873

  3. House dust mites possess a polymorphic, single domain putative peptidoglycan d,l endopeptidase belonging to the NlpC/P60 Superfamily

    PubMed Central

    Tang, Vivian H.; Stewart, Geoffrey A.; Chang, Barbara J.

    2015-01-01

    A 14 kDa protein homologous to the ?-d-glutamyl-l-diamino acid endopeptidase members of the NlpC/P60 Superfamily has been described in Dermatophagoides pteronyssinus and Dermatophagoides farinae but it is not clear whether other species produce homologues. Bioinformatics revealed homologous genes in other Sarcopteformes mite species (Psoroptes ovis and Blomia tropicalis) but not in Tetranychus urticae and Metaseiulus occidentalis. The degrees of identity (similarity) between the D. pteronyssinus mature protein and those from D. farinae, P. ovis and B. tropicalis were 82% (96%), 77% (93%) and 61% (82%), respectively. Phylogenetic studies showed the mite proteins were monophyletic and shared a common ancestor with both actinomycetes and ascomycetes. The gene encoding the D. pteronyssinus protein was polymorphic and intronless in contrast to that reported for D. farinae. Homology studies suggest that the mite, ascomycete and actinomycete proteins are involved in the catalysis of stem peptide attached to peptidoglycan. The finding of a gene encoding a P60 family member in the D. pteronyssinus genome together with the presence of a bacterial promotor suggests an evolutionary link to one or more prokaryotic endosymbionts. PMID:26566476

  4. Implications of Cellobiohydrolase Glycosylation for use in Biomass Conversion

    SciTech Connect

    Jeoh, T.; Michener W.; Himmel, M. E.; Decker, S. R.; Adney, W. S.

    2008-01-01

    The cellulase producing ascomycete, Trichoderma reesei (Hypocrea jecorina), is known to secrete a range of enzymes important for ethanol production from lignocellulosic biomass. It is also widely used for the commercial scale production of industrial enzymes because of its ability to produce high titers of heterologous proteins. During the secretion process, a number of post-translational events can occur, however, that impact protein function and stability. Another ascomycete, Aspergillus niger var. awamori, is also known to produce large quantities of heterologous proteins for industry. In this study, T. reesei Cel7A, a cellobiohydrolase, was expressed in A. niger var. awamori and subjected to detailed biophysical characterization. The purified recombinant enzyme contains six times the amount of N-linked glycan than the enzyme purified from a commercial T. reesei enzyme preparation. The activities of the two enzyme forms were compared using bacterial (microcrystalline) and phosphoric acid swollen (amorphous) cellulose as substrates. This comparison suggested that the increased level of N-glycosylation of the recombinant Cel7A (rCel7A) resulted in reduced activity and increased non-productive binding on cellulose. When treated with the N-glycosidase PNGaseF, the molecular weight of the recombinant enzyme approached that of the commercial enzyme and the activity on cellulose was improved.

  5. New, rare or remarkable microfungi in the Italian Alps (Carnic Alps)--part I--ascomycotina.

    PubMed

    Feige, G B; Ale-Agha, N; Jensen, M; Christiaans, B; Kricke, R

    2004-01-01

    During our observations in the SE part of the Carnic Alps in the year 2003 we were able to collect and identify 35 ascomycetes on trees and dead wood. Among these one can find numerous ascomycetes of different orders e.g. Pyrenomycetes, Loculoascomycetes and Discomycetes. Some species like Botryosphaeria ribis GROSENLUCHER & DUGGAR on Ribes alpinum L., Dothiora pyrenophora (FR.) FR. on Sorbus aucuparia L., Gemmamyces piceae (BORTH.) CASAGO. on Picea excelsa (LAM.) LINK, Glomerella montana (SACC.) v. ARX & E. MULLER on Sesleria caerulea (L.) ARD, Hymenoscyphus immutabilis (Fuck.) Dennis on Alnus incana (L.) Moench, Hysterographium fraxini (PERS. Ex. FR.) de Not. on Fraxinus ornus L., Lachnellula willkommii (Hartig) DENNIS [= Trichascyphella willkommii (Hartig) NANNF.] on Larix decidua MILL.,Leptosphaeria lycopodina (Mont.) SACC. on Lycopodium annotinum L., Mollisia adenostylidis REHM. on Adenostyles glabra (MILL.) DC., Pezicula cinnamomea (DC.)SACC. [ana: Cryptosporiopsis quercina PETRAK] on Quercus robur L., Pyrenopeziza petiolaris (A. & S. Ex FR.) NANNF. on Acer pseudoplatanus L., Tapesia rosae (PERS.) FUCKEL on Rosa canina L., are new for this area. All specimen are deposited in the Herbarium ESS Mycotheca Parva, Collection G.B. Feige/N. Ale-Agha. PMID:15756826

  6. Candida ficus sp. nov., a novel yeast species from the gut of Apriona germari larvae.

    PubMed

    Hui, Feng-Li; Niu, Qiu-Hong; Ke, Tao; Liu, Zheng

    2012-11-01

    A novel yeast species is described based on three strains from the gut of wood-boring larvae collected in a tree trunk of Ficus carica cultivated in parks near Nanyang, central China. Phylogenetic analysis based on sequences of the D1/D2 domains of the large subunit rRNA gene showed that these strains occurred in a separate clade that was genetically distinct from all known ascomycetous yeasts. In terms of pairwise sequence divergence, the novel strains differed by 15.3% divergence from the type strain of Pichia terricola, and by 15.8% divergence from the type strains of Pichia exigua and Candida rugopelliculosa in the D1/D2 domains. All three are ascomycetous yeasts in the Pichia clade. Unlike P. terricola, P. exigua and C. rugopelliculosa, the novel isolates did not ferment glucose. The name Candida ficus sp. nov. is proposed to accommodate these highly divergent organisms, with STN-8(T) (=CICC 1980(T)=CBS 12638(T)) as the type strain. PMID:22729023

  7. Community composition of root-associated fungi in a Quercus-dominated temperate forest: “codominance” of mycorrhizal and root-endophytic fungi

    PubMed Central

    Toju, Hirokazu; Yamamoto, Satoshi; Sato, Hirotoshi; Tanabe, Akifumi S; Gilbert, Gregory S; Kadowaki, Kohmei

    2013-01-01

    In terrestrial ecosystems, plant roots are colonized by various clades of mycorrhizal and endophytic fungi. Focused on the root systems of an oak-dominated temperate forest in Japan, we used 454 pyrosequencing to explore how phylogenetically diverse fungi constitute an ecological community of multiple ecotypes. In total, 345 operational taxonomic units (OTUs) of fungi were found from 159 terminal-root samples from 12 plant species occurring in the forest. Due to the dominance of an oak species (Quercus serrata), diverse ectomycorrhizal clades such as Russula, Lactarius, Cortinarius, Tomentella, Amanita, Boletus, and Cenococcum were observed. Unexpectedly, the root-associated fungal community was dominated by root-endophytic ascomycetes in Helotiales, Chaetothyriales, and Rhytismatales. Overall, 55.3% of root samples were colonized by both the commonly observed ascomycetes and ectomycorrhizal fungi; 75.0% of the root samples of the dominant Q. serrata were so cocolonized. Overall, this study revealed that root-associated fungal communities of oak-dominated temperate forests were dominated not only by ectomycorrhizal fungi but also by diverse root endophytes and that potential ecological interactions between the two ecotypes may be important to understand the complex assembly processes of belowground fungal communities. PMID:23762515

  8. The reassignment of three 'lost' Taphrina species (Taphrina bullata, Taphrina insititiae and Taphrina rhizophora) supported by the divergence of nuclear and mitochondrial DNA.

    PubMed

    Petrydesová, Jana; Bacigálová, Kamila; Sulo, Pavol

    2013-08-01

    The ascomycetous genus Taphrina Fries originally contained more than 90 phytopathogenic microscopic dimorphic ascomycetes causing specific infections in different vascular plants. Although species have mainly been identified historically according to their host and morphological and physiological traits, they can be studied and preserved in the form of yeasts arising from germinating ascospores. Due to low DNA sequence divergence and the lack of available strains, the number of accepted Taphrina species has currently been reduced to 28. The aim of this study is the description of three previously accepted species. Taphrina bullata (type strain CCY 58-4-1 = CBS 12783), Taphrina insititiae (type strain CCY 58-5-1 = CBS 12782) and Taphrina rhizophora (type strain CCY 58-6-1 = CBS 12781), which have been omitted from a recent key. The host range, the divergence of the 26S rRNA gene sequence, internal transcribed spacers (ITS) and the mitochondrial small ribosomal subunit (rns) sequence strongly support their reassignment as species. PMID:23710051

  9. Characteristics of nucleosomes and linker DNA regions on the genome of the basidiomycete Mixia osmundae revealed by mono- and dinucleosome mapping

    PubMed Central

    Nishida, Hiromi; Kondo, Shinji; Matsumoto, Takashi; Suzuki, Yutaka; Yoshikawa, Hirofumi; Taylor, Todd D.; Sugiyama, Junta

    2012-01-01

    We present findings on the nucleosomal arrangement in the genome of the basidiomycete Mixia osmundae, focusing on nucleosomal linker DNA regions. We have assembled the genomic sequences of M. osmundae, annotated genes and transcription start sites (TSSs) on the genome, and created a detailed nucleosome map based on sequencing mono- and dinucleosomal DNA fragments. The nucleosomal DNA length distribution of M. osmundae is similar to that of the filamentous ascomycete Aspergillus fumigatus, but differs from that of ascomycetous yeasts, strongly suggesting that nucleosome positioning has evolved primarily through neutral drift in fungal species. We found clear association between dinucleotide frequencies and linker DNA regions mapped as the midpoints of dinucleosomes. We also describe a unique pattern found in the nucleosome-depleted region upstream of the TSS observed in the dinucleosome map and the precursor status of dinucleosomes prior to the digestion into mononucleosomes by comparing the mono- and dinucleosome maps. We demonstrate that observation of dinucleosomes as well as of mononucleosomes is valuable in investigating nucleosomal organization of the genome. PMID:22724063

  10. Yeasts and yeast-like fungi associated with tree bark: diversity and identification of yeasts producing extracellular endoxylanases.

    PubMed

    Bhadra, Bhaskar; Rao, R Sreenivas; Singh, Pavan K; Sarkar, Partha K; Shivaji, Sisinthy

    2008-05-01

    A total of 239 yeast strains was isolated from 52 tree bark samples of the Medaram and Srisailam forest areas of Andhra Pradesh, India. Based on analysis of D1/D2 domain sequence of 26S rRNA gene, 114 strains were identified as ascomycetous; 107 strains were identified as basidiomycetous yeasts; and 18 strains were identified as yeast-like fungi. Among the ascomycetous yeasts, 51% were identified as members of the genus Pichia, and the remaining 49% included species belonging to the genera Clavispora, Debaryomyces, Kluyveromyces, Hanseniaspora, Issatchenkia, Lodderomyces, Kodamaea, Metschnikowia, and Torulaspora. The predominant genera in the basidiomycetous yeasts were Cryptococcus (48.6%), Rhodotorula (29%), and Rhodosporidium (12.1%). The yeast-like fungi were represented by Aureobasidium pullulans (6.7%) and Lecythophora hoffmanii (0.8%). Of the 239 yeast strains tested for Xylanase, only five strains of Aureobasidium sp. produced xylanase on xylan-agar medium. Matrix-assisted laser desorption ionization-time of flight analysis and N-terminal amino-acid sequence of the xylanase of isolate YS67 showed high similarity with endo-1-4-beta-xylanase (EC 3.2.1.8) of Aureobasidium pullulans var. melanigenum. PMID:18219522

  11. Antifungal Susceptibility Profiles of 1698 Yeast Reference Strains Revealing Potential Emerging Human Pathogens

    PubMed Central

    Desnos-Ollivier, Marie; Robert, Vincent; Raoux-Barbot, Dorothée; Groenewald, Marizeth; Dromer, Françoise

    2012-01-01

    New molecular identification techniques and the increased number of patients with various immune defects or underlying conditions lead to the emergence and/or the description of novel species of human and animal fungal opportunistic pathogens. Antifungal susceptibility provides important information for ecological, epidemiological and therapeutic issues. The aim of this study was to assess the potential risk of the various species based on their antifungal drug resistance, keeping in mind the methodological limitations. Antifungal susceptibility profiles to the five classes of antifungal drugs (polyens, azoles, echinocandins, allylamines and antimetabolites) were determined for 1698 yeast reference strains belonging to 992 species (634 Ascomycetes and 358 Basidiomycetes). Interestingly, geometric mean minimum inhibitory concentrations (MICs) of all antifungal drugs tested were significantly higher for Basidiomycetes compared to Ascomycetes (p<0.001). Twenty four strains belonging to 23 species of which 19 were Basidiomycetes seem to be intrinsically “resistant” to all drugs. Comparison of the antifungal susceptibility profiles of the 4240 clinical isolates and the 315 reference strains belonging to 53 shared species showed similar results. Even in the absence of demonstrated in vitro/in vivo correlation, knowing the in vitro susceptibility to systemic antifungal agents and the putative intrinsic resistance of yeast species present in the environment is important because they could become opportunistic pathogens. PMID:22396754

  12. The diversity of yeasts associated with grapes and musts of the Strekov winegrowing region, Slovakia.

    PubMed

    Nemcová, Kornélia; Breierová, Emília; Vadkertiová, Renáta; Molnárová, Jana

    2015-03-01

    Many different yeast species have been isolated from grapes and musts worldwide. The diversity and frequency of yeasts depend on a number of factors such as the grape variety, the physical damage of the grapes, the weather conditions and the chemical composition of must. A total of 366 isolates were associated with the three grape cultivars: Blue Frankish, Green Veltliner and Sauvignon blanc over four consecutive years. Yeast cultures were isolated from the grapes and from the fermenting musts after the first and seventh days. The ascomycetous yeasts of the genera Aureobasidium, Candida, Hanseniaspora, Metschnikowia, Pichia, Saccharomyces and Saccharomycopsis together with basidiomycetous yeasts of the genera Cryptococcus, Dioszegia, Filobasidium, Rhodotorula and Sporidiobolus were associated with the three grape varieties. Hanseniaspora uvarum, Metschnikowia pulcherrima, Pichia kluyveri, Pichia kudriavzevii and Sporidiobolus pararoseus were found on the berries in significant amounts. P. kluyveri and P. kudriavzevii were more associated with the damaged grapes, whereas Sp. pararoseus with intact ones. H. uvarum and M. pulcherrima were present on both types of grapes almost equally. The yeast composition and quantitative representation of yeast species varied over the grape varieties and the years examined. Although the basidiomycetous species formed a significant proportion of the yeast population in some individual grape variety/year combinations, the ascomycetous species were dominant. PMID:25253264

  13. Plant-Polysaccharide-Degrading Enzymes from Basidiomycetes

    PubMed Central

    Rytioja, Johanna; Hildén, Kristiina; Yuzon, Jennifer; Hatakka, Annele; de Vries, Ronald P.

    2014-01-01

    SUMMARY Basidiomycete fungi subsist on various types of plant material in diverse environments, from living and dead trees and forest litter to crops and grasses and to decaying plant matter in soils. Due to the variation in their natural carbon sources, basidiomycetes have highly varied plant-polysaccharide-degrading capabilities. This topic is not as well studied for basidiomycetes as for ascomycete fungi, which are the main sources of knowledge on fungal plant polysaccharide degradation. Research on plant-biomass-decaying fungi has focused on isolating enzymes for current and future applications, such as for the production of fuels, the food industry, and waste treatment. More recently, genomic studies of basidiomycete fungi have provided a profound view of the plant-biomass-degrading potential of wood-rotting, litter-decomposing, plant-pathogenic, and ectomycorrhizal (ECM) basidiomycetes. This review summarizes the current knowledge on plant polysaccharide depolymerization by basidiomycete species from diverse habitats. In addition, these data are compared to those for the most broadly studied ascomycete genus, Aspergillus, to provide insight into specific features of basidiomycetes with respect to plant polysaccharide degradation. PMID:25428937

  14. Distribution and evolution of glycoside hydrolase family 45 cellulases in nematodes and fungi

    PubMed Central

    2014-01-01

    Background Horizontal gene transfer (HGT) has been suggested as the mechanism by which various plant parasitic nematode species have obtained genes important in parasitism. In particular, cellulase genes have been acquired by plant parasitic nematodes that allow them to digest plant cell walls. Unlike the typical glycoside hydrolase (GH) family 5 cellulase genes which are found in several nematode species from the order Tylenchida, members of the GH45 cellulase have only been identified in a cluster including the families Parasitaphelenchidae (with the pinewood nematode Bursaphelenchus xylophilus) and Aphelenchoididae, and their origins remain unknown. Results In order to investigate the distribution and evolution of GH45 cellulase genes in nematodes and fungi we performed a wide ranging screen for novel putative GH45 sequences. This revealed that the sequences are widespread mainly in Ascomycetous fungi and have so far been found in a single major nematode lineage. Close relationships between the sequences from nematodes and fungi were found through our phylogenetic analyses. An intron position is shared by sequences from Bursaphelenchus nematodes and several Ascomycetous fungal species. Conclusions The close phylogenetic relationships and conserved gene structure between the sequences from nematodes and fungi strongly supports the hypothesis that nematode GH45 cellulase genes were acquired via HGT from fungi. The rapid duplication and turnover of these genes within Bursaphelenchus genomes demonstrate that useful sequences acquired via HGT can become established in the genomes of recipient organisms and may open novel niches for these organisms to exploit. PMID:24690293

  15. Sebacinales form ectendomycorrhizas with Cavendishia nobilis, a member of the Andean clade of Ericaceae, in the mountain rain forest of southern Ecuador.

    PubMed

    Setaro, Sabrina; Weiss, Michael; Oberwinkler, Franz; Kottke, Ingrid

    2006-01-01

    Cavendishia nobilis var. capitata is an endemic member of the Ericaceae growing as a hemiepiphyte in the tropical mountain rain forest of southern Ecuador. Mycorrhizas were collected from 20 individuals along an altitudinal gradient between 1850 and 2300 m. Transmission electron microscopy was used to study the symbiotic association in detail, and phylogenetic analyses based on nuclear rDNA coding for the ribosomal large subunit (nucLSU) were carried out to identify the associated mycorrhizal fungi. Microscopic and ultrastructural investigations showed the formation of a hyphal sheath, intercellular penetration of fine hyphae and colonization of the cortical cells by swollen hyphae of the same fungus. These structures were formed by hymenomycetes and ascomycetes. Molecular phylogenetic analysis detected seven groups of mycorrhizal fungi belonging to the Sebacinales. This is the first study to obtain evidence of ectendomycorrhizas in the Vaccinioideae. The ascomycetous nucLSU sequences belonged to members of the Leotiomycetes. The ectendomycorrhiza of C. nobilis with Sebacinales is discussed as a specific, hitherto undescribed mycorrhizal subcategory of ectomycorrhizas. We propose the term 'cavendishioid mycorrhiza'. This subcategory is most likely specific for the Andean clade of Ericaceae. PMID:16411938

  16. De Novo Biosynthesis of Vanillin in Fission Yeast (Schizosaccharomyces pombe) and Baker's Yeast (Saccharomyces cerevisiae) ?

    PubMed Central

    Hansen, Esben H.; Mřller, Birger Lindberg; Kock, Gertrud R.; Bünner, Camilla M.; Kristensen, Charlotte; Jensen, Ole R.; Okkels, Finn T.; Olsen, Carl E.; Motawia, Mohammed S.; Hansen, Jřrgen

    2009-01-01

    Vanillin is one of the world's most important flavor compounds, with a global market of 180 million dollars. Natural vanillin is derived from the cured seed pods of the vanilla orchid (Vanilla planifolia), but most of the world's vanillin is synthesized from petrochemicals or wood pulp lignins. We have established a true de novo biosynthetic pathway for vanillin production from glucose in Schizosaccharomyces pombe, also known as fission yeast or African beer yeast, as well as in baker's yeast, Saccharomyces cerevisiae. Productivities were 65 and 45 mg/liter, after introduction of three and four heterologous genes, respectively. The engineered pathways involve incorporation of 3-dehydroshikimate dehydratase from the dung mold Podospora pauciseta, an aromatic carboxylic acid reductase (ACAR) from a bacterium of the Nocardia genus, and an O-methyltransferase from Homo sapiens. In S. cerevisiae, the ACAR enzyme required activation by phosphopantetheinylation, and this was achieved by coexpression of a Corynebacterium glutamicum phosphopantetheinyl transferase. Prevention of reduction of vanillin to vanillyl alcohol was achieved by knockout of the host alcohol dehydrogenase ADH6. In S. pombe, the biosynthesis was further improved by introduction of an Arabidopsis thaliana family 1 UDP-glycosyltransferase, converting vanillin into vanillin ?-d-glucoside, which is not toxic to the yeast cells and thus may be accumulated in larger amounts. These de novo pathways represent the first examples of one-cell microbial generation of these valuable compounds from glucose. S. pombe yeast has not previously been metabolically engineered to produce any valuable, industrially scalable, white biotech commodity. PMID:19286778

  17. De novo biosynthesis of vanillin in fission yeast (Schizosaccharomyces pombe) and baker's yeast (Saccharomyces cerevisiae).

    PubMed

    Hansen, Esben H; Mřller, Birger Lindberg; Kock, Gertrud R; Bünner, Camilla M; Kristensen, Charlotte; Jensen, Ole R; Okkels, Finn T; Olsen, Carl E; Motawia, Mohammed S; Hansen, Jřrgen

    2009-05-01

    Vanillin is one of the world's most important flavor compounds, with a global market of 180 million dollars. Natural vanillin is derived from the cured seed pods of the vanilla orchid (Vanilla planifolia), but most of the world's vanillin is synthesized from petrochemicals or wood pulp lignins. We have established a true de novo biosynthetic pathway for vanillin production from glucose in Schizosaccharomyces pombe, also known as fission yeast or African beer yeast, as well as in baker's yeast, Saccharomyces cerevisiae. Productivities were 65 and 45 mg/liter, after introduction of three and four heterologous genes, respectively. The engineered pathways involve incorporation of 3-dehydroshikimate dehydratase from the dung mold Podospora pauciseta, an aromatic carboxylic acid reductase (ACAR) from a bacterium of the Nocardia genus, and an O-methyltransferase from Homo sapiens. In S. cerevisiae, the ACAR enzyme required activation by phosphopantetheinylation, and this was achieved by coexpression of a Corynebacterium glutamicum phosphopantetheinyl transferase. Prevention of reduction of vanillin to vanillyl alcohol was achieved by knockout of the host alcohol dehydrogenase ADH6. In S. pombe, the biosynthesis was further improved by introduction of an Arabidopsis thaliana family 1 UDP-glycosyltransferase, converting vanillin into vanillin beta-D-glucoside, which is not toxic to the yeast cells and thus may be accumulated in larger amounts. These de novo pathways represent the first examples of one-cell microbial generation of these valuable compounds from glucose. S. pombe yeast has not previously been metabolically engineered to produce any valuable, industrially scalable, white biotech commodity. PMID:19286778

  18. Illumina MiSeq investigations on the changes of microbial community in the Fusarium oxysporum f.sp. cubense infected soil during and after reductive soil disinfestation.

    PubMed

    Huang, Xinqi; Liu, Liangliang; Wen, Teng; Zhu, Rui; Zhang, Jinbo; Cai, Zucong

    2015-12-01

    Although reductive soil disinfestation (RSD) is increasingly used for the control of soil-borne diseases, its impact on the soil microbial community during and after RSD remains poorly understood. MiSeq pyrosequencing, real-time PCR and denaturing gradient gel electrophoresis were performed to investigate the changes of microbial community in the Fusarium oxysporum f. sp. cubense (FOC) infected soil during RSD and at the simulative banana cultivation after RSD. The results showed that RSD significantly increased soil microbial populations and a different microbial community with the pathogenic soil was established after RSD. Specifically, the number of Firmicutes mainly containing Ruminococcus and Coprococcus followed by a small part of Clostridium which were the dominant bacterial genera significantly increased during RSD. In contrast, Symbiobacterium and Flavisolibacter were the dominant genera in the flooding soil. When the soils were recovered under aerobic condition, the relative abundances of the bacteria belonging to the phylum Bacteroidetes, Acidobacteria, Planctomycetes increased as alternatives to the reducing Firmicutes. For fungi, the population of F. oxysporum significantly decreased during RSD accompanied with the pH decline, which resulted in the significant decrease of relative abundance in the phylum Ascomycota. Alternatively, the relative abundances of some other fungal species increased, such as Chaetomium spp. and Penicillium spp. belonging to Ascomycota and the family Clavulinaceae belonging to Basidiomycota. Then, the relative abundance of Ascomycota re-increased after RSD with Podospora and Zopfiella as dominant genera, whereas the relative abundance of Fusarium further decreased. Overall, the microbial populations and community re-established by RSD made the soil more disease-suppressive and beneficial to the soil nutrient cycling and plant growth compared with the previous pathogenic soil. PMID:26640050

  19. How past and present influence the foraging of clonal plants?

    PubMed

    Louâpre, Philipe; Bittebičre, Anne-Kristel; Clément, Bernard; Pierre, Jean-Sébastien; Mony, Cendrine

    2012-01-01

    Clonal plants spreading horizontally and forming a network structure of ramets exhibit complex growth patterns to maximize resource uptake from the environment. They respond to spatial heterogeneity by changing their internode length or branching frequency. Ramets definitively root in the soil but stay interconnected for a varying period of time thus allowing an exchange of spatial and temporal information. We quantified the foraging response of clonal plants depending on the local soil quality sampled by the rooting ramet (i.e. the present information) and the resource variability sampled by the older ramets (i.e. the past information). We demonstrated that two related species, Potentilla reptans and P. anserina, responded similarly to the local quality of their environment by decreasing their internode length in response to nutrient-rich soil. Only P. reptans responded to resource variability by decreasing its internode length. In both species, the experience acquired by older ramets influenced the plastic response of new rooted ramets: the internode length between ramets depended not only on the soil quality locally sampled but also on the soil quality previously sampled by older ramets. We quantified the effect of the information perceived at different time and space on the foraging behavior of clonal plants by showing a non-linear response of the ramet rooting in the soil of a given quality. These data suggest that the decision to grow a stolon or to root a ramet at a given distance from the older ramet results from the integration of the past and present information about the richness and the variability of the environment. PMID:22675539

  20. The Complete Mitochondrial Genome of Bean Goose (Anser fabalis) and Implications for Anseriformes Taxonomy

    PubMed Central

    Liu, Gang; Zhou, Lizhi; Zhang, Lili; Luo, Zijun; Xu, Wenbin

    2013-01-01

    Mitochondrial DNA plays an important role in living organisms, and has been used as a powerful molecular marker in a variety of evolutionary studies. In this study, we determined the complete mtDNA of Bean goose (Anser fabalis), which is 16,688 bp long and contains 13 protein-coding genes, 2 rRNAs, 22 tRNAs and a control region. The arrangement is similar to that of typical Anseriform species. All protein-coding genes, except for Cyt b, ND5, COI, and COII, start with an ATG codon. The ATG start codon is also generally observed in the 12 other Anseriform species, including 2 Anser species, with sequenced mitochondrial genomes. TAA is the most frequent stop codon, one of three–TAA, TAG, and T- –commonly observed in Anseriformes. All tRNAs could be folded into canonical cloverleaf secondary structures except for tRNASer(AGY) and tRNALeu(CUN), which are missing the dihydrouridine (DHU) arm. The control region of Bean goose mtDNA, with some conserved sequence boxes, such as F, E, D, and C, identified in its central domain. Phylogenetic analysis of complete mtDNA data for 13 Anseriform species supports the classification of them into four major branches: Anatinae, Anserinae, Dendrocygninae and Anseranatidae. Phylogenetic analyses were also conducted on 36 Anseriform birds using combined Cyt b, ND2, and COI sequences. The results clearly support the genus Somateria as an independent lineage classified in its own tribe, the Somaterini. Recovered topologies from both complete mtDNA and combined DNA sequences strongly indicate that Dendrocygninae is an independent subfamily within the family Anatidae and Anseranatidae represents an independent family. Based on the results of this study, we conclude that combining ND2, Cyt b, and COI sequence data is a workable solution at present for resolving phylogenetic relationships among Anseriform species in the absence of sufficient complete mtDNA data. PMID:23717412

  1. Secretion of acid phosphatase in Claviceps purpurea--an ultracytochemical study.

    PubMed

    Vorísek, J; Kalachová, L

    2003-01-01

    The lead phosphate precipitation method showed the reaction product of acid phosphatase (which reflects the presence of the enzyme glycoprotein) in peripheral cytoplasmic vesicles in the ascomycetous fungus Claviceps purpurea. The product appeared to diffuse from these vesicles (diameter 100-200 nm) towards the cell wall, usually to its sites covered by the capsular fibres exhibiting also acid phosphatase activity. This observation of diffusion of secretory glycoprotein in the cytoplasmic matrix and its orientation to the plasmalemma and capsular fibrils suggests an alternative to the well-described secretory mechanism of transport and exocytosis of glycoproteins via membrane-bound transport conveyors fusing with the cell membrane. It confirms and enlarges our previous finding of the reaction product of acid phosphatase performed by ultrastructural cytochemistry in vacuoles (lysosomes), in the growing cell septum, in cytoplasmic vesicles and in the fibres of the external capsule. PMID:15058189

  2. Untargeted Metabolic Profiling of Winery-Derived Biomass Waste Degradation by Penicillium chrysogenum.

    PubMed

    Karpe, Avinash V; Beale, David J; Godhani, Nainesh B; Morrison, Paul D; Harding, Ian H; Palombo, Enzo A

    2015-12-16

    Winery-derived biomass waste was degraded by Penicillium chrysogenum under solid state fermentation over 8 days in a (2)H2O-supplemented medium. Multivariate statistical analysis of the gas chromatography-mass spectrometry (GC-MS) data resulted in the identification of 94 significant metabolites, within 28 different metabolic pathways. The majority of biomass sugars were utilized by day 4 to yield products such as sugars, fatty acids, isoprenoids, and amino acids. The fungus was observed to metabolize xylose to xylitol, an intermediate of ethanol production. However, enzyme inhibition and autolysis were observed from day 6, indicating 5 days as the optimal time for fermentation. P. chrysogenum displayed metabolism of pentoses (to alcohols) and degraded tannins and lignins, properties that are lacking in other biomass-degrading ascomycetes. Rapid fermentation (3-5 days) may not only increase the pentose metabolizing efficiency but also increase the yield of medicinally important metabolites, such as syringate. PMID:26611372

  3. Marine Fungi: Their Ecology and Molecular Diversity

    NASA Astrophysics Data System (ADS)

    Richards, Thomas A.; Jones, Meredith D. M.; Leonard, Guy; Bass, David

    2012-01-01

    Fungi appear to be rare in marine environments. There are relatively few marine isolates in culture, and fungal small subunit ribosomal DNA (SSU rDNA) sequences are rarely recovered in marine clone library experiments (i.e., culture-independent sequence surveys of eukaryotic microbial diversity from environmental DNA samples). To explore the diversity of marine fungi, we took a broad selection of SSU rDNA data sets and calculated a summary phylogeny. Bringing these data together identified a diverse collection of marine fungi, including sequences branching close to chytrids (flagellated fungi), filamentous hypha-forming fungi, and multicellular fungi. However, the majority of the sequences branched with ascomycete and basidiomycete yeasts. We discuss evidence for 36 novel marine lineages, the majority and most divergent of which branch with the chytrids. We then investigate what these data mean for the evolutionary history of the Fungi and specifically marine-terrestrial transitions. Finally, we discuss the roles of fungi in marine ecosystems.

  4. Comprehensive Metabolomic, Lipidomic and Microscopic Profiling of Yarrowia lipolytica during Lipid Accumulation Identifies Targets for Increased Lipogenesis

    PubMed Central

    Pomraning, Kyle R.; Wei, Siwei; Karagiosis, Sue A.; Kim, Young-Mo; Dohnalkova, Alice C.; Arey, Bruce W.; Bredeweg, Erin L.; Orr, Galya; Metz, Thomas O.; Baker, Scott E.

    2015-01-01

    Yarrowia lipolytica is an oleaginous ascomycete yeast that accumulates large amounts of lipids and has potential as a biofuel producing organism. Despite a growing scientific literature focused on lipid production by Y. lipolytica, there remain significant knowledge gaps regarding the key biological processes involved. We applied a combination of metabolomic and lipidomic profiling approaches as well as microscopic techniques to identify and characterize the key pathways involved in de novo lipid accumulation from glucose in batch cultured, wild-type Y. lipolytica. We found that lipids accumulated rapidly and peaked at 48 hours during the five day experiment, concurrent with a shift in amino acid metabolism. We also report that exhaustion of extracellular sugars coincided with thickening of the cell wall, suggesting that genes involved in cell wall biogenesis may be a useful target for improving the efficiency of lipid producing yeast strains. PMID:25905710

  5. Aspergillus Niger Genomics: Past, Present and into the Future

    SciTech Connect

    Baker, Scott E.

    2006-09-01

    Aspergillus niger is a filamentous ascomycete fungus that is ubiquitous in the environment and has been implicated in opportunistic infections of humans. In addition to its role as an opportunistic human pathogen, A. niger is economically important as a fermentation organism used for the production of citric acid. Industrial citric acid production by A. niger represents one of the most efficient, highest yield bioprocesses in use currently by industry. The genome size of A. niger is estimated to be between 35.5 and 38.5 megabases (Mb) divided among eight chromosomes/linkage groups that vary in size from 3.5 - 6.6 Mb. Currently, there are three independent A. niger genome projects, an indication of the economic importance of this organism. The rich amount of data resulting from these multiple A. niger genome sequences will be used for basic and applied research programs applicable to fermentation process development, morphology and pathogenicity.

  6. A second quadrivirus strain from the phytopathogenic filamentous fungus Rosellinia necatrix.

    PubMed

    Lin, Yu-Hsin; Hisano, Sakae; Yaegashi, Hajime; Kanematsu, Satoko; Suzuki, Nobuhiro

    2013-05-01

    We report the biological and molecular characterisation ofa second quadrivirus strain termed Rosellinia necatrix quadrivirus 1 strain W1118 (RnQV1-W1118) from the ascomycete white root rot fungus. Commonalities with the first quadrivirus (RnQV1-W1075) include its quadripartite genome structure, spherical particle morphology, sequence heterogeneity in the extreme terminal end, 72–82%sequence identity between the corresponding proteins, and its ability to cause a latent infection. Distinguishing features include different conserved terminal sequences and the degree of susceptibility of two major capsid proteins to proteolytic degradation, which is thought to occur during virion purification. Identification of this second quadrivirus strain strengthens our earlier proposal that ‘‘Rosellinia necatrix quadrivirus 1’’ should be considered the type species of a novel family, ‘‘Quadriviridae’’. PMID:23277362

  7. Scytalidium and scytalidiosis: what's new in 2012?

    PubMed

    Machouart, M; Menir, P; Helenon, R; Quist, D; Desbois, N

    2013-03-01

    Fungi belonging to the genus Scytalidium are widespread around the world. Among them, two species are responsible for human superficial infections mimicking dermatophytosis: Neoscytalidium dimidiatum and Scytalidium hyalinum. Whereas these ascomycetous fungi are endemic in tropical or subtropical countries, both species have a different geographical distribution. Scytalidiosis represents approximately 40% of dermatomycoses in these areas. A few cases of invasive infections due to Scytalidium sp. have also been reported, assessing the ability of these fungi to behave as opportunists. Here we have reviewed the data on N. dimidiatum and S. hyalinum concerning their classification, clinical features, diagnosis and treatment. We also have presented the example of a specific consultation dedicated to nails in Martinique, in order to optimize the diagnosis and treatment of onychomycosis, many of which being due to Scytalidium sp. Even if Scytalidium cases are still rare in temperate countries, imported cases may increase in the future due to immigration and travel. PMID:23416171

  8. Evolution of regulatory networks in Candida glabrata: learning to live with the human host.

    PubMed

    Roy, Sushmita; Thompson, Dawn

    2015-12-01

    The opportunistic human fungal pathogen Candida glabrata is second only to C. albicans as the cause of Candida infections and yet is more closely related to Saccharomyces cerevisiae. Recent advances in functional genomics technologies and computational approaches to decipher regulatory networks, and the comparison of these networks among these and other Ascomycete species, have revealed both unique and shared strategies in adaptation to a human commensal/opportunistic pathogen lifestyle and antifungal drug resistance in C. glabrata. Recently, several C. glabrata sister species in the Nakeseomyces clade representing both human associated (commensal) and environmental isolates have had their genomes sequenced and analyzed. This has paved the way for comparative functional genomics studies to characterize the regulatory networks in these species to identify informative patterns of conservation and divergence linked to phenotypic evolution in the Nakaseomyces lineage. PMID:26449820

  9. Protein kinase A signaling and calcium ions are major players in PAF mediated toxicity against Aspergillus niger

    PubMed Central

    Binder, Ulrike; Ben?ina, Mojca; Fizil, Ádám; Batta, Gyula; Chhillar, Anil K.; Marx, Florentine

    2015-01-01

    The Penicillium chrysogenum antifungal protein PAF is toxic against potentially pathogenic Ascomycetes. We used the highly sensitive aequorin-expressing model Aspergillus niger to identify a defined change in cytoplasmic free Ca2+ dynamics in response to PAF. This Ca2+ signature depended on an intact positively charged lysine-rich PAF motif. By combining Ca2+ measurements in A. niger mutants with deregulated cAMP/protein kinase A (PKA) signaling, we proved the interconnection of Ca2+ perturbation and cAMP/PKA signaling in the mechanistic function of PAF. A deep understanding of the mode of action of PAF is an invaluable prerequisite for its future application as new antifungal drug. PMID:25882631

  10. Trichosporon Species Isolated from Guano Samples Obtained from Bat-Inhabited Caves in Japan

    PubMed Central

    Sugita, Takashi; Kikuchi, Ken; Makimura, Koichi; Urata, Kensaku; Someya, Takashi; Kamei, Katsuhiko; Niimi, Masakazu; Uehara, Yoshimasa

    2005-01-01

    Yeasts from caves have rarely been examined. We examined yeasts collected from bat guano samples from 20 bat-inhabited limestone and volcanic caves located in 11 prefectures in Japan. Of ?700 yeast-like colonies, nine Trichosporon species were recovered from 15 caves. Two of these were known species, and the remaining seven are potentially novel species, based on molecular phylogenetic analyses. In addition to Trichosporon species, identifiable strains of eight ascomycetous yeasts and one basidiomycetous yeast were recovered at frequencies of 5 to 35%. Our findings suggest that Trichosporon spp. are the major yeast species in bat guano in Japan and that bat guano is a potentially rich source of previously undescribed yeast species. PMID:16269819

  11. Fusarium circinatum isolates from northern Spain are commonly infected by three distinct mitoviruses.

    PubMed

    Vainio, Eeva J; Martínez-Álvarez, Pablo; Bezos, Diana; Hantula, Jarkko; Diez, Julio J

    2015-08-01

    Pitch canker is a serious disease of pines caused by the ascomycete fungus Gibberella circinata (anamorph = Fusarium circinatum). Three distinct mitovirus strains have been described in this fungus: Fusarium circinatum mitovirus 1 (FcMV1), FcMV2-1 and FcMV2-2. Here, we investigated the frequency and population variation of these viruses and closely related sequence variants in northern Spain using RT-PCR and sequencing. Each virus strain and similar sequence variants shared >95 % sequence identity and were collectively designated as virus types. All virus types were relatively common in Spain, with estimated prevalence of 18.5 %, 8.9 % and 16.3 % for FcMV1, FcMV2-1 and FcMV2-2, respectively. PMID:26025157

  12. Comparative genomics of Taphrina fungi causing varying degrees of tumorous deformity in plants.

    PubMed

    Tsai, Isheng J; Tanaka, Eiji; Masuya, Hayato; Tanaka, Ryusei; Hirooka, Yuuri; Endoh, Rikiya; Sahashi, Norio; Kikuchi, Taisei

    2014-04-01

    Taphrina fungi are biotrophic plant pathogens that cause plant deformity diseases. We sequenced the genomes of four Taphrina species-Taphrina wiesneri, T. deformans, T. flavorubra, and T. populina-which parasitize Prunus, Cerasus, and Populus hosts with varying severity of disease symptoms. High levels of gene synteny within Taphrina species were observed, and our comparative analysis further revealed that these fungi may utilize multiple strategies in coping with the host environment that are also found in some specialized dimorphic species. These include species-specific aneuploidy and clusters of highly diverged secreted proteins located at subtelomeres. We also identified species differences in plant hormone biosynthesis pathways, which may contribute to varying degree of disease symptoms. The genomes provide a rich resource for investigation into Taphrina biology and evolutionary studies across the basal ascomycetes clade. PMID:24682155

  13. Comparative Genomics of Taphrina Fungi Causing Varying Degrees of Tumorous Deformity in Plants

    PubMed Central

    Tsai, Isheng J.; Tanaka, Eiji; Masuya, Hayato; Tanaka, Ryusei; Hirooka, Yuuri; Endoh, Rikiya; Sahashi, Norio; Kikuchi, Taisei

    2014-01-01

    Taphrina fungi are biotrophic plant pathogens that cause plant deformity diseases. We sequenced the genomes of four Taphrina species—Taphrina wiesneri, T. deformans, T. flavorubra, and T. populina—which parasitize Prunus, Cerasus, and Populus hosts with varying severity of disease symptoms. High levels of gene synteny within Taphrina species were observed, and our comparative analysis further revealed that these fungi may utilize multiple strategies in coping with the host environment that are also found in some specialized dimorphic species. These include species-specific aneuploidy and clusters of highly diverged secreted proteins located at subtelomeres. We also identified species differences in plant hormone biosynthesis pathways, which may contribute to varying degree of disease symptoms. The genomes provide a rich resource for investigation into Taphrina biology and evolutionary studies across the basal ascomycetes clade. PMID:24682155

  14. Manipulation of culture conditions alters lipid content and fatty acid profiles of a wide variety of known and new oleaginous yeasts species

    PubMed Central

    Sitepu, Irnayuli R.; Sestric, Ryan; Ignatia, Laura; Levin, David; German, J. Bruce; Gillies, Laura A.; Almada, Luis A.G.; Boundy-Mills, Kyria L.

    2013-01-01

    Oleaginous yeasts have been studied for oleochemical production for over 80 years. Only a few species have been studied intensely. To expand the diversity of oleaginous yeasts available for lipid research, we surveyed a broad diversity of yeasts with indicators of oleaginicity including known oleaginous clades, and buoyancy. Sixty-nine strains representing 17 genera and 50 species were screened for lipid production. Yeasts belonged to Ascomycota families, Basidiomycota orders, and the yeast-like algal genus Prototheca. Total intracellular lipids and fatty acid composition were determined under different incubation times and nitrogen availability. Thirteen new oleaginous yeast species were discovered, representing multiple ascomycete and basidiomycete clades. Nitrogen starvation generally increased intracellular lipid content. The fatty acid profiles varied with the growth conditions regardless of taxonomic affiliation. The dominant fatty acids were oleic acid, palmitic acid, linoleic acid, and stearic acid. Yeasts and culture conditions that produced fatty acids appropriate for biodiesel were identified. PMID:23891835

  15. Mushroom heteropolysaccharides: A review on their sources, structure and biological effects.

    PubMed

    Ruthes, Andrea C; Smiderle, Fhernanda R; Iacomini, Marcello

    2016-01-20

    Mushrooms have been largely studied not only by their d-glucans, but also because they present a class of more complex polymers: the heteropolysaccharides. Heteropolysaccharides show variability on their monosaccharide composition, anomeric configuration, linkage and branching type, besides some of these molecules can present natural methylated monosaccharides and also acid monosaccharides, which enhance the difficulty of the purification and characterization of their structure. As a result of such complexity, mushroom heteropolysaccharides can be considered an interesting source of molecules with medicinal and industrial applications. Consequently a plenty of new researches has been published in the past 12 years about the isolation, chemical characterization and biological activities of heteropolysaccharides from mushrooms, especially from Basidiomycetes. Therefore, this review intends to organize and classify the information described up to now about such polysaccharides obtained from different sources of mushroom-forming fungi, Basidiomycetes, Ascomycetes and Hybrid mushrooms, and provides a brief reflection on how the chemical studies have been carried out. PMID:26572366

  16. Genomic analyses and expression evaluation of thaumatin-like gene family in the cacao fungal pathogen Moniliophthora perniciosa.

    PubMed

    Franco, Sulamita de Freitas; Baroni, Renata Moro; Carazzolle, Marcelo Falsarella; Teixeira, Paulo José Pereira Lima; Reis, Osvaldo; Pereira, Gonçalo Amarante Guimarăes; Mondego, Jorge Maurício Costa

    2015-10-30

    Thaumatin-like proteins (TLPs) are found in diverse eukaryotes. Plant TLPs, known as Pathogenicity Related Protein (PR-5), are considered fungal inhibitors. However, genes encoding TLPs are frequently found in fungal genomes. In this work, we have identified that Moniliophthora perniciosa, a basidiomycete pathogen that causes the Witches' Broom Disease (WBD) of cacao, presents thirteen putative TLPs from which four are expressed during WBD progression. One of them is similar to small TLPs, which are present in phytopathogenic basidiomycete, such as wheat stem rust fungus Puccinia graminis. Fungi genomes annotation and phylogenetic data revealed a larger number of TLPs in basidiomycetes when comparing with ascomycetes, suggesting that these proteins could be involved in specific traits of mushroom-forming species. Based on the present data, we discuss the contribution of TLPs in the combat against fungal competitors and hypothesize a role of these proteins in M. perniciosa pathogenicity. PMID:26367180

  17. Plant biomass degradation by fungi.

    PubMed

    Mäkelä, Miia R; Donofrio, Nicole; de Vries, Ronald P

    2014-11-01

    Plant biomass degradation by fungi has implications for several fields of science. The enzyme systems employed by fungi for this are broadly used in various industrial sectors such as food & feed, pulp & paper, detergents, textile, wine, and more recently biofuels and biochemicals. In addition, the topic is highly relevant in the field of plant pathogenic fungi as they degrade plant biomass to either gain access to the plant or as carbon source, resulting in significant crop losses. Finally, fungi are the main degraders of plant biomass in nature and as such have an essential role in the global carbon cycle and ecology in general. In this review we provide a global view on the development of this research topic in saprobic ascomycetes and basidiomycetes and in plant pathogenic fungi and link this to the other papers of this special issue on plant biomass degradation by fungi. PMID:25192611

  18. Fungal Sex and Pathogenesis

    PubMed Central

    Butler, Geraldine

    2010-01-01

    Summary: Human fungal pathogens are associated with diseases ranging from dandruff and skin colonization to invasive bloodstream infections. The major human pathogens belong to the Candida, Aspergillus, and Cryptococcus clades, and infections have high and increasing morbidity and mortality. Many human fungal pathogens were originally assumed to be asexual. However, recent advances in genome sequencing, which revealed that many species have retained the genes required for the sexual machinery, have dramatically influenced our understanding of the biology of these organisms. Predictions of a rare or cryptic sexual cycle have been supported experimentally for some species. Here, I examine the evidence that human pathogens reproduce sexually. The evolution of the mating-type locus in ascomycetes (including Candida and Aspergillus species) and basidiomycetes (Malassezia and Cryptococcus) is discussed. I provide an overview of how sex is suppressed in different species and discuss the potential associations with pathogenesis. PMID:20065328

  19. Ancient fungi in Antarctic permafrost environments.

    PubMed

    Kochkina, Galina; Ivanushkina, Natalya; Ozerskaya, Svetlana; Chigineva, Nadezhda; Vasilenko, Oleg; Firsov, Sergey; Spirina, Elena; Gilichinsky, David

    2012-11-01

    Filamentous fungi in 36 samples of Antarctic permafrost sediments were studied. The samples collected during the Russian Antarctic expedition of 2007-2009 within the framework of the Antarctic Permafrost Age Project (ANTPAGE) were recovered from different depths in ice-free oases located along the perimeter of the continent. Fungal diversity was determined by conventional microbiological techniques combined with a culture-independent method based on the analysis of internal transcribed spacer (ITS2) sequences in total DNA of the samples. The study revealed a rather low fungal population density in permafrost, although the diversity found was appreciable, representing more than 26 genera. Comparison of the data obtained by different techniques showed that the culture-independent method enabled the detection of ascomycetous and basidiomycetous fungi not found by culturing. The molecular method failed to detect members of the genera Penicillium and Cladosporium that possess small-sized spores known to have a high resistance to environmental changes. PMID:22757669

  20. Comprehensive metabolomic, lipidomic and microscopic profiling of Yarrowia lipolytica during lipid accumulation identifies targets for increased lipogenesis

    SciTech Connect

    Pomraning, Kyle R.; Wei, Siwei; Karagiosis, Sue A.; Kim, Young-Mo; Dohnalkova, Alice; Arey, Bruce W.; Bredeweg, Erin L.; Orr, Galya; Metz, Thomas O.; Baker, Scott E.

    2015-04-23

    Yarrowia lipolytica is an oleaginous ascomycete yeast that accumulates large amounts of lipids and has potential as a biofuel producing organism. Despite a growing scientific literature focused on lipid production by Y. lipolytica, there remain significant knowledge gaps regarding the key biological processes involved. We applied a combination of metabolomic and lipidomic profiling approaches as well as microscopic techniques to identify and characterize the key pathways involved in de novo lipid accumulation from glucose in batch cultured, wild-type Y. lipolytica. We found that lipids accumulated rapidly and peaked at 48 hours during the five day experiment, concurrent with a shift in amino acid metabolism. We also report that Y. lipolytica secretes disaccharides early in batch culture and reabsorbs them when extracellular glucose is depleted. Exhaustion of extracellular sugars coincided with thickening of the cell wall, suggesting that genes involved in cell wall biogenesis may be a useful target for improving the efficiency of lipid producing yeast strains.

  1. Live cell imaging of endosomal trafficking in fungi.

    PubMed

    Baumann, Sebastian; Takeshita, Norio; Grün, Nathalie; Fischer, Reinhard; Feldbrügge, Michael

    2015-01-01

    Endosomes are multipurpose membranous carriers important for endocytosis and secretion. During membrane trafficking, endosomes transport lipids, proteins, and even RNAs. In highly polarized cells such as fungal hyphae, they shuttle bidirectionally along microtubules mediated by molecular motors like kinesins and dynein. For in vivo studies of these highly dynamic protein/membrane complexes, advanced fluorescence microscopy is instrumental. In this chapter, we describe live cell imaging of endosomes in two distantly related fungal model systems, the basidiomycete Ustilago maydis and the ascomycete Aspergillus nidulans. We provide insights into live cell imaging of dynamic endosomal proteins and RNA, dual-color detection for colocalization studies, as well as fluorescence recovery after photobleaching (FRAP) for quantification and photo-activated localization microscopy (PALM) for super-resolution. These methods described in two well-studied fungal model systems are applicable to a broad range of other organisms. PMID:25702128

  2. Bioactive fungal polysaccharides as potential functional ingredients in food and nutraceuticals.

    PubMed

    Giavasis, Ioannis

    2014-04-01

    Fungal bioactive polysaccharides deriving mainly from the Basidiomycetes family (and some from the Ascomycetes) and medicinal mushrooms have been well known and widely used in far Asia as part of traditional diet and medicine, and in the last decades have been the core of intense research for the understanding and the utilization of their medicinal properties in naturally produced pharmaceuticals. In fact, some of these biopolymers (mainly ?-glucans or heteropolysaccharides) have already made their way to the market as antitumor, immunostimulating or prophylactic drugs. The fact that many of these biopolymers are produced by edible mushrooms makes them also very good candidates for the formulation of novel functional foods and nutraceuticals without any serious safety concerns, in order to make use of their immunomodulating, anticancer, antimicrobial, hypocholesterolemic, hypoglycemic and health-promoting properties. This article summarizes the most important properties and applications of bioactive fungal polysaccharides and discusses the latest developments on the utilization of these biopolymers in human nutrition. PMID:24518400

  3. Psychrotrophic yeast Yarrowia lipolytica NCYC 789 mediates the synthesis of antimicrobial silver nanoparticles via cell-associated melanin

    PubMed Central

    2013-01-01

    A psychrotrophic marine strain of the ascomycetous yeast Yarrowia lipolytica (NCYC 789) synthesized silver nanoparticles (AgNPs) in a cell-associated manner. These nanostructures were characterized by UV-Visible spectroscopy and scanning electron microscope-energy dispersive spectrometer (SEM-EDS) analysis. The brown pigment (melanin) involved in metal-interactions was obtained from the cells. This extracted pigment also mediated the synthesis of silver nanoparticles that were characterized by a variety of analytical techniques. The melanin-derived nanoparticles displayed antibiofilm activity. This paper thus reports the synthesis of AgNPs by the biotechnologically important yeast Y. lipolytica; proposes a possible mechanism involved in the synthetic process and describes the use of the bio-inspired nanoparticles as antibiofilm agents. PMID:23758863

  4. Sympatric genetic differentiation of a generalist pathogenic fungus, Botrytis cinerea, on two different host plants, grapevine and bramble.

    PubMed

    Fournier, E; Giraud, T

    2008-01-01

    Prime candidates for sympatric ecological divergence include parasites that differentiate via host shifts, because different host species exert strong disruptive selection and because both hosts and parasites are continually co-evolving. Sympatric divergence may be fostered even more strongly in phytopathogenic fungi, in particular those where sex must occur on the host, which allows adaptation alone to restrict gene flow between populations developing on different hosts. We sampled populations of Botrytis cinerea, a generalist ascomycete fungus, on sympatric grapes and brambles in six regions in France. Microsatellite data were analyzed using standard population genetics, a population graph analysis and a Bayesian approach. In addition to confirming that B. cinerea reproduces sexually, our results showed that the fungal populations on the two hosts were significantly differentiated, indicating restricted gene flow, even in sympatry. In contrast, only weak geographical differentiation could be detected. These results support the possibility of sympatric divergence associated with host use in generalist parasites. PMID:18028352

  5. Genomic tillage and the harvest of fungal phytopathogens.

    PubMed

    Oliver, Richard

    2012-12-01

    Genome sequencing has been carried out on a small selection of major fungal ascomycete pathogens. These studies show that simple models whereby pathogens evolved from phylogenetically related saprobes by the acquisition or modification of a small number of key genes cannot be sustained.The genomes show that pathogens cannot be divided into three clearly delineated classes (biotrophs, hemibiotrophs and necrotrophs) but rather into a complex matrix of categories each with subtly different properties. It is clear that the evolution of pathogenicity is ancient, rapid and ongoing. Fungal pathogens have undergone substantial genomic rearrangements that can be appropriately described as 'genomic tillage'. Genomic tillage underpins the evolution and expression of large families of genes - known as effectors - that manipulate and exploit metabolic and defence processes of plants so as to allow the proliferation of pathogens. PMID:22998436

  6. [Characteristic of the yeast isolated from patients with leukaemia].

    PubMed

    Fedorovskaia, E A; Rybal'skaia, A P; Skachkova, N K; Mel'nik, E A; Nemirovskaia, L N; Nagornaia, S S; Babich, T V; Polishchuk, L V

    2008-01-01

    It has been shown that biotopes of upper respiratory system and intestine were contaminated with yeast in 44.6% of patients with leukaemia (of 112 examined ones). Their quantity exceeds the boundary value for practically healthy people and is > or = 10(2) KOE/ml in the nasal activity and fauces and < or = 10(4) KOE/g in the intestine. It was established that in patients with leucemia the mycotic complications are mainly caused by anamorphous yeast of ascomycetic affinity. Candida albicans, as well as C. glabrata, C. rugosa and Candida sp. play the leading role. The Candida genus species are mainly sensitive to amphotericine B, clotrisamol and nistatin. PMID:19044007

  7. Aminoadipate reductase gene: a new fungal-specific gene for comparative evolutionary analyses

    PubMed Central

    An, Kwang-Deuk; Nishida, Hiromi; Miura, Yoshiharu; Yokota, Akira

    2002-01-01

    Background In fungi, aminoadipate reductase converts 2-aminoadipate to 2-aminoadipate 6-semialdehyde. However, other organisms have no homologue to the aminoadipate reductase gene and this pathway appears to be restricted to fungi. In this study, we designed degenerate primers for polymerase chain reaction (PCR) amplification of a large fragment of the aminoadipate reductase gene for divergent fungi. Results Using these primers, we amplified DNA fragments from the archiascomycetous yeast Saitoella complicata and the black-koji mold Aspergillus awamori. Based on an alignment of the deduced amino acid sequences, we constructed phylogenetic trees. These trees are consistent with current ascomycete systematics and demonstrate the potential utility of the aminoadipete reductase gene for phylogenetic analyses of fungi. Conclusions We believe that the comparison of aminoadipate reductase among species will be useful for molecular ecological and evolutionary studies of fungi, because this enzyme-encoding gene is a fungal-specific gene and generally appears to be single copy. PMID:11931673

  8. Killer activity of Tilletiopsis albescens Gokhale: taxonomic and phylogenetic implication.

    PubMed

    Golubev, W

    1998-08-01

    Killer activity expressed at pH values ranging from 3.5 to 8.0 was found in the Tilletiopsis albescens VKM-2822. Its killer phenotype was cureless. The toxin excreted with a molecular mass above 10 kDa is fungicidal, thermolabile, sensitive to proteinase K and was specified as a mycocin. The latter does not act against ascomycetous, sporidiobolaceous and tremellaceous yeasts. In contrast to all other Rhodotorula species, Rh. bacarum, Rh. hinnulea and Rh. phylloplana are sensitive to the mycocin studied. Also, its killing pattern includes the species of the genera Exobasidium, Farysia, Protomyces, Pseudozyma, Sporisorium, Taphrina and Ustilago. The host range of T. albescens mycocin is discussed from taxonomic and phylogenetic viewpoints. PMID:9779608

  9. Fungicide Effects on Fungal Community Composition in the Wheat Phyllosphere

    PubMed Central

    Karlsson, Ida; Friberg, Hanna; Steinberg, Christian; Persson, Paula

    2014-01-01

    The fungicides used to control diseases in cereal production can have adverse effects on non-target fungi, with possible consequences for plant health and productivity. This study examined fungicide effects on fungal communities on winter wheat leaves in two areas of Sweden. High-throughput 454 sequencing of the fungal ITS2 region yielded 235 operational taxonomic units (OTUs) at the species level from the 18 fields studied. It was found that commonly used fungicides had moderate but significant effect on fungal community composition in the wheat phyllosphere. The relative abundance of several saprotrophs was altered by fungicide use, while the effect on common wheat pathogens was mixed. The fungal community on wheat leaves consisted mainly of basidiomycete yeasts, saprotrophic ascomycetes and plant pathogens. A core set of six fungal OTUs representing saprotrophic species was identified. These were present across all fields, although overall the difference in OTU richness was large between the two areas studied. PMID:25369054

  10. Entomotoxic and nematotoxic lectins and protease inhibitors from fungal fruiting bodies.

    PubMed

    Saboti?, Jerica; Ohm, Robin A; Künzler, Markus

    2016-01-01

    Fruiting bodies or sporocarps of dikaryotic (ascomycetous and basidiomycetous) fungi, commonly referred to as mushrooms, are often rich in entomotoxic and nematotoxic proteins that include lectins and protease inhibitors. These protein toxins are thought to act as effectors of an innate defense system of mushrooms against animal predators including fungivorous insects and nematodes. In this review, we summarize current knowledge about the structures, target molecules, and regulation of the biosynthesis of the best characterized representatives of these fungal defense proteins, including galectins, beta-trefoil-type lectins, actinoporin-type lectins, beta-propeller-type lectins and beta-trefoil-type chimerolectins, as well as mycospin and mycocypin families of protease inhibitors. We also present an overview of the phylogenetic distribution of these proteins among a selection of fungal genomes and draw some conclusions about their evolution and physiological function. Finally, we present an outlook for future research directions in this field and their potential applications in medicine and crop protection. PMID:26521246

  11. Mycosphaerella is polyphyletic

    PubMed Central

    Crous, P.W.; Braun, U.; Groenewald, J.Z.

    2007-01-01

    Mycosphaerella, one of the largest genera of ascomycetes, encompasses several thousand species and has anamorphs residing in more than 30 form genera. Although previous phylogenetic studies based on the ITS rDNA locus supported the monophyly of the genus, DNA sequence data derived from the LSU gene distinguish several clades and families in what has hitherto been considered to represent the Mycosphaerellaceae. Several important leaf spotting and extremotolerant species need to be disposed to the genus Teratosphaeria, for which a new family, the Teratosphaeriaceae, is introduced. Other distinct clades represent the Schizothyriaceae, Davidiellaceae, Capnodiaceae, and the Mycosphaerellaceae. Within the two major clades, namely Teratosphaeriaceae and Mycosphaerellaceae, most anamorph genera are polyphyletic, and new anamorph concepts need to be derived to cope with dual nomenclature within the Mycosphaerella complex. PMID:18490994

  12. Use of new endophytic fungi as pretreatment to enhance enzymatic saccharification of Eucalyptus globulus.

    PubMed

    Martín-Sampedro, Raquel; Fillat, Úrsula; Ibarra, David; Eugenio, María E

    2015-11-01

    New endophytic fungi are assessed for the first time as pretreatment to enhance saccharification of Eucalyptus globulus wood. The fungi are all laccase-producing ascomycetes and were isolated from eucalyptus trees in Spain. After five endophytes had been assayed alone or in combination with white-rot fungus Trametes sp. I-62, three were pre-selected. To improve sugar production, an autohydrolysis pretreatment was performed before or after fungal treatment. Pretreatment increased sugar production 2.7 times compared to non-pretreated wood. When fungal and autohydrolysis pretreatments were combined, a synergistic increase in saccharification was observed in all cases. Endophytic fungi Ulocladium sp. and Hormonema sp. produced greater enhancements in saccharification than Trametes sp. I-62 (increase in sugar yields of 8.5, 8.0 and 6.0 times, respectively), demonstrating the high potential of these new endophytic fungi for saccharification enhancement. PMID:26255602

  13. Comprehensive metabolomic, lipidomic and microscopic profiling of Yarrowia lipolytica during lipid accumulation identifies targets for increased lipogenesis

    DOE PAGESBeta

    Pomraning, Kyle R.; Wei, Siwei; Karagiosis, Sue A.; Kim, Young-Mo; Dohnalkova, Alice; Arey, Bruce W.; Bredeweg, Erin L.; Orr, Galya; Metz, Thomas O.; Baker, Scott E.

    2015-04-23

    Yarrowia lipolytica is an oleaginous ascomycete yeast that accumulates large amounts of lipids and has potential as a biofuel producing organism. Despite a growing scientific literature focused on lipid production by Y. lipolytica, there remain significant knowledge gaps regarding the key biological processes involved. We applied a combination of metabolomic and lipidomic profiling approaches as well as microscopic techniques to identify and characterize the key pathways involved in de novo lipid accumulation from glucose in batch cultured, wild-type Y. lipolytica. We found that lipids accumulated rapidly and peaked at 48 hours during the five day experiment, concurrent with a shiftmore »in amino acid metabolism. We also report that Y. lipolytica secretes disaccharides early in batch culture and reabsorbs them when extracellular glucose is depleted. Exhaustion of extracellular sugars coincided with thickening of the cell wall, suggesting that genes involved in cell wall biogenesis may be a useful target for improving the efficiency of lipid producing yeast strains.« less

  14. Thelebolus microsporus mycelial mats in the trachea of wild brown skua (Catharacta antarctica lonnbergi) and South Polar skua (C. maccormicki) carcasses.

    PubMed

    Leotta, Gerardo A; Paré, Jean A; Sigler, Lynne; Montalti, Diego; Vigo, Germán; Petruccelli, Miguel; Reinoso, Enso H

    2002-04-01

    Sixteen brown skuas (Catharacta antarctica lonnbergi) and seven South Polar skuas (C. maccormicki) were found dead near Boekella Lake, Hope Bay, Antarctica, in February 1997. Postmortem examination revealed conspicuous caseous, deep yellow fungal/mycelial mats or cores in the trachea of nine of 19 carcasses that were examined. These mycelial cores, highly suggestive of aspergillomas, completely occluded the tracheal lumen in four of these nine carcasses. Thelebolus microsporus, a psychrophilic ascomycetous fungus commonly isolated from skua dung and skua nesting material, was isolated in pure culture from these tracheal plugs. Awareness of pseudolesions resulting from Thelebolus microsporus profuse postmortem growth in the trachea of dead skuas will minimize potential confusion with aspergillosis when investigating causes of epornithics in Antarctica. PMID:12038146

  15. A novel water-soluble beta-(1-->6)-D-glucan isolated from the fruit bodies of Bulgaria inquinans (Fries).

    PubMed

    Bi, Hongtao; Ni, Xiuzhen; Liu, Xiaoyu; Iteku, Jeff; Tai, Guihua; Zhou, Yifa; Zhao, Jimin

    2009-07-01

    A low molecular-weight polysaccharide named BIWP2 was purified from the fruit bodies of Bulgaria Inquinans (Fries) via hot-water extraction, followed by freeze-thawing and gel filtration chromatography on Sephadex G-75. Monosaccharide composition analysis revealed that BIWP2 contained exclusively glucose. High performance size exclusion chromatography (HPSEC) showed that it was a homogeneous polysaccharide fraction. Its molecular weight was estimated to be 2.6 KD and the polydispersity index (M(w)/M(n)) was calculated to be 1.4. Periodate oxidation, methylation, and NMR analyses indicated that BIWP2 was a linear beta-(1-->6)-D-glucan without side chains. This is the first time to report a linear beta-(1-->6)-D-glucan with low molecular weight in non-lichenized ascomycete. PMID:19467650

  16. Colletotrichum orbiculare FAM1 Encodes a Novel Woronin Body-Associated Pex22 Peroxin Required for Appressorium-Mediated Plant Infection

    PubMed Central

    Fujihara, Naoki; Harata, Ken; Neumann, Ulla; Robin, Guillaume P.; O’Connell, Richard

    2015-01-01

    ABSTRACT The cucumber anthracnose fungus Colletotrichum orbiculare forms specialized cells called appressoria for host penetration. We identified a gene, FAM1, encoding a novel peroxin protein that is essential for peroxisome biogenesis and that associates with Woronin bodies (WBs), dense-core vesicles found only in filamentous ascomycete fungi which function to maintain cellular integrity. The fam1 disrupted mutants were unable to grow on medium containing oleic acids as the sole carbon source and were nonpathogenic, being defective in both appressorium melanization and host penetration. Fluorescent proteins carrying peroxisomal targeting signals (PTSs) were not imported into the peroxisomes of fam1 mutants, suggesting that FAM1 is a novel peroxisomal biogenesis gene (peroxin). FAM1 did not show significant homology to any Saccharomyces cerevisiae peroxins but resembled conserved filamentous ascomycete-specific Pex22-like proteins which contain a predicted Pex4-binding site and are potentially involved in recycling PTS receptors from peroxisomes to the cytosol. C. orbiculare FAM1 complemented the peroxisomal matrix protein import defect of the S. cerevisiae pex22 mutant. Confocal microscopy of Fam1-GFP (green fluorescent protein) fusion proteins and immunoelectron microscopy with anti-Fam1 antibodies showed that Fam1 localized to nascent WBs budding from peroxisomes and mature WBs. Association of Fam1 with WBs was confirmed by colocalization with WB matrix protein CoHex1 (C. orbiculare Hex1) and WB membrane protein CoWsc (C. orbiculare Wsc) and by subcellular fractionation and Western blotting with antibodies to Fam1 and CoHex1. In WB-deficient cohex1 mutants, Fam1 was redirected to the peroxisome membrane. Our results show that Fam1 is a WB-associated peroxin required for pathogenesis and raise the possibility that localized receptor recycling occurs in WBs. PMID:26374121

  17. Mating Type Locus of Chinese Black Truffles Reveals Heterothallism and the Presence of Cryptic Species within the T. indicum Species Complex

    PubMed Central

    Belfiori, Beatrice; Riccioni, Claudia; Paolocci, Francesco; Rubini, Andrea

    2013-01-01

    Tuber spp. are filamentous ascomycetes which establish symbiosis with the roots of trees and shrub species. By virtue of this symbiosis they produce hypogeous ascocarps, known as truffles. Filamentous ascomycetes can reproduce by homothallism or heterothallism depending on the structure and organization of their mating type locus. The first mating type locus in a truffle species has been recently characterized in Tuber melanosporum and it has been shown that this fungus, endemic in Europe, is heterothallic. The availability of sequence information for T. melanosporum mating type genes is seminal to cloning their orthologs from other Tuber species and assessing their reproductive mode. Here we report on the organization of the mating type region in T. indicum, the black truffle species present in Asia, which is the closest relative to T. melanosporum and is characterized by an high level of morphological and genetic variability. The present study shows that T. indicum is also heterothallic. Examination of Asiatic black truffles belonging to different genetic classes, sorted according to the sequence polymorphism of the internal transcribed spacer rDNA region, has revealed sequence variations and rearrangements in both coding and non-coding regions of the mating type locus, to suggest the existence of cryptic species within the T. indicum complex. The presence of transposable elements within or linked to the mating type region suggests a role of these elements in generating the genotypic diversity present among T. indicum strains. Overall, comparative analyses of the mating type locus have thus allowed us to tackle taxonomical and phylogenetic issues within black truffles and make inferences about the evolution of T. melanosporum-T. indicum lineage. Our results are not only of fundamental but also of applied relevance as T. indicum produces edible fruit bodies that are imported also into Europe and thus may represent a biological threat for T. melanosporum. PMID:24358175

  18. The diversity and extracellular enzymatic activities of yeasts isolated from water tanks of Vriesea minarum, an endangered bromeliad species in Brazil, and the description of Occultifur brasiliensis f.a., sp. nov.

    PubMed

    Gomes, Fátima C O; Safar, Silvana V B; Marques, Andrea R; Medeiros, Adriana O; Santos, Ana Raquel O; Carvalho, Cláudia; Lachance, Marc-André; Sampaio, José Paulo; Rosa, Carlos A

    2015-02-01

    The diversity of yeast species collected from the bromeliad tanks of Vriesea minarum, an endangered bromeliad species, and their ability to produce extracellular enzymes were studied. Water samples were collected from 30 tanks of bromeliads living in a rupestrian field site located at Serrada Piedade, Minas Gerais state, Brazil, during both the dry and rainy seasons. Thirty-six species were isolated, representing 22 basidiomycetous and 14 ascomycetous species. Occultifur sp., Cryptococcus podzolicus and Cryptococcus sp. 1 were the prevalent basidiomycetous species. The yeast-like fungus from the order Myriangiales, Candida silvae and Aureobasidium pullulans were the most frequent ascomycetous species. The diversity of the yeast communities obtained between seasons was not significantly different, but the yeast composition per bromeliad was different between seasons. These results suggest that there is significant spatial heterogeneity in the composition of populations of the yeast communities within bromeliad tanks, independent of the season. Among the 352 yeast isolates tested, 282 showed at least one enzymatic activity. Protease activity was the most widely expressed extracellular enzymatic activity, followed by xylanase, amylase, pectinase and cellulase activities. These enzymes may increase the carbon and nitrogen availability for the microbial food web in the bromeliad tank of V. minarum. Sequence analyses revealed the existence of 10 new species, indicating that bromeliad tanks are important sources of new yeasts. The novel species Occultifur brasiliensis, f.a., sp. nov., is proposed to accommodate the most frequently isolated yeast associated with V. minarum. The type strain of O. brasiliensis, f.a., sp. nov. is UFMG-CM-Y375(T) (= CBS 12687(T)). The Mycobank number is MB 809816. PMID:25515414

  19. The genome of Nectria haematococca: contribution of supernumerary chromosomes to gene expansion

    SciTech Connect

    Coleman, J.J.; Rounsley, S.D.; Rodriguez-Carres, M.; Kuo, A.; Wasmann, C.c.; Grimwood, J.; Schmutz, J.; Taga, M.; White, G.J.; Zhuo, S.; Schwartz, D.C.; Freitag, M.; Ma, L.-J.; Danchin, E.G.J.; Henrissat, B.; Cutinho, P.M.; Nelson, D.R.; Straney, D.; Napoli, C.A.; Baker, B.M.; Gribskov, M.; Rep, M.; Kroken, S.; Molnar, I.; Rensing, C.; Kennell, J.C.; Zamora, J.; Farman, M.L.; Selker, E.U.; Salamov, A.; Shapiro, H.; Pangilinan, J.; Lindquist, E.; Lamers, C.; Grigoriev, I.V.; Geiser, D.M.; Covert, S.F.; Temporini, S.; VanEtten, H.D.

    2009-04-20

    The ascomycetous fungus Nectria haematococca, (asexual name Fusarium solani), is a member of a group of .50 species known as the"Fusarium solani species complex". Members of this complex have diverse biological properties including the ability to cause disease on .100 genera of plants and opportunistic infections in humans. The current research analyzed the most extensively studied member of this complex, N. haematococca mating population VI (MPVI). Several genes controlling the ability of individual isolates of this species to colonize specific habitats are located on supernumerary chromosomes. Optical mapping revealed that the sequenced isolate has 17 chromosomes ranging from 530 kb to 6.52 Mb and that the physical size of the genome, 54.43 Mb, and the number of predicted genes, 15,707, are among the largest reported for ascomycetes. Two classes of genes have contributed to gene expansion: specific genes that are not found in other fungi including its closest sequenced relative, Fusarium graminearum; and genes that commonly occur as single copies in other fungi but are present as multiple copies in N. haematococca MPVI. Some of these additional genes appear to have resulted from gene duplication events, while others may have been acquired through horizontal gene transfer. The supernumerary nature of three chromosomes, 14, 15, and 17, was confirmed by their absence in pulsed field gel electrophoresis experiments of some isolates and by demonstrating that these isolates lacked chromosome-specific sequences found on the ends of these chromosomes. These supernumerary chromosomes contain more repeat sequences, are enriched in unique and duplicated genes, and have a lower G+C content in comparison to the other chromosomes. Although the origin(s) of the extra genes and the supernumerary chromosomes is not known, the gene expansion and its large genome size are consistent with this species' diverse range of habitats. Furthermore, the presence of unique genes on supernumerary chromosomes might account for individual isolates having different environmental niches.

  20. The information highways of a biotechnological workhorse – signal transduction in Hypocrea jecorina

    PubMed Central

    Schmoll, Monika

    2008-01-01

    Background The ascomycete Hypocrea jecorina (anamorph Trichoderma reesei) is one of the most prolific producers of biomass-degrading enzymes and frequently termed an industrial workhorse. To compete for nutrients in its habitat despite its shortcoming in certain degradative enzymes, efficient perception and interpretation of environmental signals is indispensable. A better understanding of these signals as well as their transmission machinery can provide sources for improvement of biotechnological processes. Results The genome of H. jecorina was analysed for the presence and composition of common signal transduction pathways including heterotrimeric G-protein cascades, cAMP signaling, mitogen activated protein kinases, two component phosphorelay systems, proteins involved in circadian rhythmicity and light response, calcium signaling and the superfamily of Ras small GTPases. The results of this survey are discussed in the context of current knowledge in order to assess putative functions as well as potential impact of alterations of the respective pathways. Conclusion Important findings include an additional, bacterial type phospholipase C protein and an additional 6-4 photolyase. Moreover the presence of 4 RGS-(Regulator of G-protein Signaling) proteins and 3 GprK-type G-protein coupled receptors comprising an RGS-domain suggest a more complex posttranslational regulation of G-protein signaling than in other ascomycetes. Also the finding, that H. jecorina, unlike yeast possesses class I phosducins which are involved in phototransduction in mammals warrants further investigation. An alteration in the regulation of circadian rhythmicity may be deduced from the extension of both the class I and II of casein kinases, homologues of which are implicated in phosphorylation of FRQ in Neurospora crassa. On the other hand, a shortage in the number of the pathogenicity related PTH11-type G-protein coupled receptors (GPCRs) as well as a lack of microbial opsins was detected. Considering its efficient enzyme system for breakdown of cellulosic materials, it came as a surprise that H. jecorina does not possess a carbon sensing GPCR. PMID:18803869

  1. Leaf and Root-Associated Fungal Assemblages Do Not Follow Similar Elevational Diversity Patterns

    PubMed Central

    Coince, Aurore; Cordier, Tristan; Lengellé, Juliette; Defossez, Emmanuel; Vacher, Corinne; Robin, Cécile

    2014-01-01

    The diversity of fungi along environmental gradients has been little explored in contrast to plants and animals. Consequently, environmental factors influencing the composition of fungal assemblages are poorly understood. The aim of this study was to determine whether the diversity and composition of leaf and root-associated fungal assemblages vary with elevation and to investigate potential explanatory variables. High-throughput sequencing of the Internal Transcribed Spacer 1 region was used to explore fungal assemblages along three elevation gradients, located in French mountainous regions. Beech forest was selected as a study system to minimise the host effect. The variation in species richness and specific composition was investigated for ascomycetes and basidiomycetes assemblages with a particular focus on root-associated ectomycorrhizal fungi. The richness of fungal communities associated with leaves or roots did not significantly relate to any of the tested environmental drivers, i.e. elevation, mean temperature, precipitation or edaphic variables such as soil pH or the ratio carbon?nitrogen. Nevertheless, the ascomycete species richness peaked at mid-temperature, illustrating a mid-domain effect model. We found that leaf and root-associated fungal assemblages did not follow similar patterns of composition with elevation. While the composition of the leaf-associated fungal assemblage correlated primarily with the mean annual temperature, the composition of root-associated fungal assemblage was explained equally by soil pH and by temperature. The ectomycorrhizal composition was also related to these variables. Our results therefore suggest that above and below-ground fungal assemblages are not controlled by the same main environmental variables. This may be due to the larger amplitude of climatic variables in the tree foliage compared to the soil environment. PMID:24971637

  2. Dynamics of Fungal Communities in Bulk and Maize Rhizosphere Soil in the Tropics

    PubMed Central

    Gomes, Newton C. Marcial; Fagbola, Olajire; Costa, Rodrigo; Rumjanek, Norma Gouvea; Buchner, Arno; Mendona-Hagler, Leda; Smalla, Kornelia

    2003-01-01

    The fungal population dynamics in soil and in the rhizospheres of two maize cultivars grown in tropical soils were studied by a cultivation-independent analysis of directly extracted DNA to provide baseline data. Soil and rhizosphere samples were taken from six plots 20, 40, and 90 days after planting in two consecutive years. A 1.65-kb fragment of the 18S ribosomal DNA (rDNA) amplified from the total community DNA was analyzed by denaturing gradient gel electrophoresis (DGGE) and by cloning and sequencing. A rhizosphere effect was observed for fungal populations at all stages of plant development. In addition, pronounced changes in the composition of fungal communities during plant growth development were found by DGGE. Similar types of fingerprints were observed in two consecutive growth periods. No major differences were detected in the fungal patterns of the two cultivars. Direct cloning of 18S rDNA fragments amplified from soil or rhizosphere DNA resulted in 75 clones matching 12 dominant DGGE bands. The clones were characterized by their HinfI restriction patterns, and 39 different clones representing each group of restriction patterns were sequenced. The cloning and sequencing approach provided information on the phylogeny of dominant amplifiable fungal populations and allowed us to determine a number of fungal phylotypes that contribute to each of the dominant DGGE bands. Based on the sequence similarity of the 18S rDNA fragment with existing fungal isolates in the database, it was shown that the rhizospheres of young maize plants seemed to select the Ascomycetes order Pleosporales, while different members of the Ascomycetes and basidiomycetic yeast were detected in the rhizospheres of senescent maize plants. PMID:12839741

  3. Identification and structure of the mating-type locus and development of PCR-based markers for mating type in powdery mildew fungi.

    PubMed

    Brewer, Marin Talbot; Cadle-Davidson, Lance; Cortesi, Paolo; Spanu, Pietro D; Milgroom, Michael G

    2011-07-01

    In ascomycetes, mating compatibility is regulated by the mating-type locus, MAT1. The objectives of this study were to identify and sequence genes at the MAT1 locus in the grape powdery mildew fungus, Erysiphe necator, to develop a PCR-based marker for determining mating type in E. necator, and to develop degenerate primers for amplification by PCR of conserved regions of mating-type idiomorphs in other powdery mildew fungi. We identified MAT1-2-1 of the MAT1-2 idiomorph in E. necator based on the homologous sequence in the genome of Blumeria graminis f. sp. hordei and we found MAT1-1-1 and MAT1-1-3 of the MAT1-1 idiomorph from transcriptome sequences of E. necator. We developed and applied a reliable PCR-based multiplex marker to confirm that genotype correlated with mating phenotype, which was determined by pairing with mating-type tester isolates. Additionally, we used the marker to genotype populations of E. necator from different Vitis spp. from throughout the USA. We found both mating types were present in all populations and mating-type ratios did not deviate from 1:1. The mating-type genes in E. necator are similar to those of other Leotiomycetes; however, the structure of the MAT1 locus in E. necator, like the MAT1-2 idiomorph of B. graminis, is markedly different from other ascomycetes in that it is greatly expanded and may contain a large amount of repetitive DNA. As a result, we were unable to amplify and sequence either idiomorph in its entirety. We designed degenerate primers that amplify conserved regions of MAT1-1 and MAT1-2 in E. necator, Podosphaera xanthii, Microsphaera syringae, and B. graminis, representing the major clades of the Erysiphales. These degenerate primers or sequences obtained in this study from these species can be used to identify and sequence MAT1 genes or design mating-type markers in other powdery mildew fungi as well. PMID:21515399

  4. The microbial ecology of wine grape berries.

    PubMed

    Barata, A; Malfeito-Ferreira, M; Loureiro, V

    2012-02-15

    Grapes have a complex microbial ecology including filamentous fungi, yeasts and bacteria with different physiological characteristics and effects upon wine production. Some species are only found in grapes, such as parasitic fungi and environmental bacteria, while others have the ability to survive and grow in wines, constituting the wine microbial consortium. This consortium covers yeast species, lactic acid bacteria and acetic acid bacteria. The proportion of these microorganisms depends on the grape ripening stage and on the availability of nutrients. Grape berries are susceptible to fungal parasites until véraison after which the microbiota of truly intact berries is similar to that of plant leaves, which is dominated by basidiomycetous yeasts (e.g. Cryptococcus spp., Rhodotorula spp. Sporobolomyces spp.) and the yeast-like fungus Aureobasidium pullulans. The cuticle of visually intact berries may bear microfissures and softens with ripening, increasing nutrient availability and explaining the possible dominance by the oxidative or weakly fermentative ascomycetous populations (e.g. Candida spp., Hanseniaspora spp., Metschnikowia spp., Pichia spp.) approaching harvest time. When grape skin is clearly damaged, the availability of high sugar concentrations on the berry surface favours the increase of ascomycetes with higher fermentative activity like Pichia spp. and Zygoascus hellenicus, including dangerous wine spoilage yeasts (e.g. Zygosaccharomyces spp., Torulaspora spp.), and of acetic acid bacteria (e.g. Gluconobacter spp., Acetobacter spp.). The sugar fermenting species Saccharomyces cerevisiae is rarely found on unblemished berries, being favoured by grape damage. Lactic acid bacteria are minor partners of grape microbiota and while being the typical agent of malolactic fermentation, Oenococcus oeni has been seldom isolated from grapes in the vineyard. Environmental ubiquitous bacteria of the genus Enterobacter spp., Enterococcus spp., Bacillus spp., Burkholderia spp., Serratia spp., Staphylococcus spp., among others, have been isolated from grapes but do not have the ability to grow in wines. Saprophytic moulds, like Botrytis cinerea, causing grey rot, or Aspergillus spp., possibly producing ochratoxin, are only active in the vineyard, although their metabolites may affect wine quality during grape processing. The impact of damaged grapes in yeast ecology has been underestimated mostly because of inaccurate grape sampling. Injured berries hidden in apparently sound bunches explain the recovery of a higher number of species when whole bunches are picked. Grape health status is the main factor affecting the microbial ecology of grapes, increasing both microbial numbers and species diversity. Therefore, the influence of abiotic (e.g. climate, rain, hail), biotic (e.g. insects, birds, phytopathogenic and saprophytic moulds) and viticultural (e.g. fungicides) factors is dependent on their primary damaging effect. PMID:22189021

  5. When CO2 kills: effects of magmatic CO2 flux on belowground biota at Mammoth Mountain, CA

    NASA Astrophysics Data System (ADS)

    McFarland, J.; Waldrop, M. P.; Mangan, M.

    2011-12-01

    The biomass, composition, and activity of the soil microbial community is tightly linked to the composition of the aboveground plant community. Microorganisms in aerobic surface soils, both free-living and plant-associated are largely structured by the availability of growth limiting carbon (C) substrates derived from plant inputs. When C availability declines following a catastrophic event such as the death of large swaths of trees, the number and composition of microorganisms in soil would be expected to decline and/or shift to unique microorganisms that have better survival strategies under starvation conditions. High concentrations of volcanic cold CO2 emanating from Mammoth Mountain near Horseshoe Lake on the southwestern edge of Long Valley Caldera, CA has resulted in a large kill zone of tree species, and associated soil microbial species. In July 2010, we assessed belowground microbial community structure in response to disturbance of the plant community along a gradient of soil CO2 concentrations grading from <0.6% (ambient forest) to >80% (no plant life). We employed a microbial community fingerprinting technique (automated ribosomal intergenic spacer analysis) to determine changes in overall community composition for three broad functional groups: fungi, bacteria, and archaea. To evaluate changes in ectomycorrhizal fungal associates along the CO2 gradient, we harvested root tips from lodgepole pine seedlings collected in unaffected forest as well as at the leading edge of colonization into the kill zone. We also measured soil C fractions (dissolved organic C, microbial biomass C, and non-extractable C) at 10 and 30 cm depth, as well as NH4+. Not surprisingly, our results indicate a precipitous decline in soil C, and microbial C with increasing soil CO2; phospholipid fatty acid analysis in conjunction with community fingerprinting indicate both a loss of fungal diversity as well as a dramatic decrease in biomass as one proceeds further into the kill zone. This observation was concomitant with a relative increase in bacterial and archaeal contributions to microbial community structure. Root tip analyses among lodgepole seedlings recolonizing the kill zone area demonstrated a significant reduction in the overall diversity of fungal symbionts, as well as a distinct shift in fungal assemblages. In particular, within elevated CO2 areas, we observed a high infection level for the ascomycetous fungi, Wilcoxina spp., which appear particularly well-adapted for colonization in disturbed environments. It remains unclear whether dominance by ascomycetes among seedlings in elevated CO2 areas represents a coordinated shift orchestrated by the plant in response to physiological stress, or whether these fungi are simply more opportunistic than their basdiomycetous counterparts. Our results demonstrate the impact of large-scale disturbances on plant-microbial interactions and belowground processes in previously forested ecosystems.

  6. Sunlight-Exposed Biofilm Microbial Communities Are Naturally Resistant to Chernobyl Ionizing-Radiation Levels

    PubMed Central

    Ragon, Marie; Restoux, Gwendal; Moreira, David; Mřller, Anders Pape; López-García, Purificación

    2011-01-01

    Background The Chernobyl accident represents a long-term experiment on the effects of exposure to ionizing radiation at the ecosystem level. Though studies of these effects on plants and animals are abundant, the study of how Chernobyl radiation levels affect prokaryotic and eukaryotic microbial communities is practically non-existent, except for a few reports on human pathogens or soil microorganisms. Environments enduring extreme desiccation and UV radiation, such as sunlight exposed biofilms could in principle select for organisms highly resistant to ionizing radiation as well. Methodology/Principal Findings To test this hypothesis, we explored the diversity of microorganisms belonging to the three domains of life by cultivation-independent approaches in biofilms developing on concrete walls or pillars in the Chernobyl area exposed to different levels of radiation, and we compared them with a similar biofilm from a non-irradiated site in Northern Ireland. Actinobacteria, Alphaproteobacteria, Bacteroidetes, Acidobacteria and Deinococcales were the most consistently detected bacterial groups, whereas green algae (Chlorophyta) and ascomycete fungi (Ascomycota) dominated within the eukaryotes. Close relatives to the most radio-resistant organisms known, including Rubrobacter species, Deinococcales and melanized ascomycete fungi were always detected. The diversity of bacteria and eukaryotes found in the most highly irradiated samples was comparable to that of less irradiated Chernobyl sites and Northern Ireland. However, the study of mutation frequencies in non-coding ITS regions versus SSU rRNA genes in members of a same actinobacterial operational taxonomic unit (OTU) present in Chernobyl samples and Northern Ireland showed a positive correlation between increased radiation and mutation rates. Conclusions/Significance Our results show that biofilm microbial communities in the most irradiated samples are comparable to non-irradiated samples in terms of general diversity patterns, despite increased mutation levels at the single-OTU level. Therefore, biofilm communities growing in sunlight exposed substrates are capable of coping with increased mutation rates and appear pre-adapted to levels of ionizing radiation in Chernobyl due to their natural adaptation to periodical desiccation and ambient UV radiation. PMID:21765911

  7. Novel Root-Fungus Symbiosis in Ericaceae: Sheathed Ericoid Mycorrhiza Formed by a Hitherto Undescribed Basidiomycete with Affinities to Trechisporales

    PubMed Central

    Vohník, Martin; Sadowsky, Jesse J.; Kohout, Petr; Lhotáková, Zuzana; Nestby, Rolf; Kola?ík, Miroslav

    2012-01-01

    Ericaceae (the heath family) are widely distributed calcifuges inhabiting soils with inherently poor nutrient status. Ericaceae overcome nutrient limitation through symbiosis with ericoid mycorrhizal (ErM) fungi that mobilize nutrients complexed in recalcitrant organic matter. At present, recognized ErM fungi include a narrow taxonomic range within the Ascomycota, and the Sebacinales, basal Hymenomycetes with unclamped hyphae and imperforate parenthesomes. Here we describe a novel type of basidiomycetous ErM symbiosis, termed ‘sheathed ericoid mycorrhiza’, discovered in two habitats in mid-Norway as a co-dominant mycorrhizal symbiosis in Vaccinium spp. The basidiomycete forming sheathed ErM possesses clamped hyphae with perforate parenthesomes, produces 1- to 3-layer sheaths around terminal parts of hair roots and colonizes their rhizodermis intracellularly forming hyphal coils typical for ErM symbiosis. Two basidiomycetous isolates were obtained from sheathed ErM and molecular and phylogenetic tools were used to determine their identity; they were also examined for the ability to form sheathed ErM and lignocellulolytic potential. Surprisingly, ITS rDNA of both conspecific isolates failed to amplify with the most commonly used primer pairs, including ITS1 and ITS1F + ITS4. Phylogenetic analysis of nuclear LSU, SSU and 5.8S rDNA indicates that the basidiomycete occupies a long branch residing in the proximity of Trechisporales and Hymenochaetales, but lacks a clear sequence relationship (>90% similarity) to fungi currently placed in these orders. The basidiomycete formed the characteristic sheathed ErM symbiosis and enhanced growth of Vaccinium spp. in vitro, and degraded a recalcitrant aromatic substrate that was left unaltered by common ErM ascomycetes. Our findings provide coherent evidence that this hitherto undescribed basidiomycete forms a morphologically distinct ErM symbiosis that may occur at significant levels under natural conditions, yet remain undetected when subject to amplification by ‘universal’ primers. The lignocellulolytic assay suggests the basidiomycete may confer host adaptations distinct from those provisioned by the so far investigated ascomycetous ErM fungi. PMID:22761814

  8. Changes in fungal communities along a boreal forest soil fertility gradient.

    PubMed

    Sterkenburg, Erica; Bahr, Adam; Brandström Durling, Mikael; Clemmensen, Karina E; Lindahl, Björn D

    2015-09-01

    Boreal forests harbour diverse fungal communities with decisive roles in decomposition and plant nutrition. Although changes in boreal plant communities along gradients in soil acidity and nitrogen (N) availability are well described, less is known about how fungal taxonomic and functional groups respond to soil fertility factors. We analysed fungal communities in humus and litter from 25 Swedish old-growth forests, ranging from N-rich Picea abies stands to acidic and N-poor Pinus sylvestris stands. 454-pyrosequencing of ITS2 amplicons was used to analyse community composition, and biomass was estimated by ergosterol analysis. Fungal community composition was significantly related to soil fertility at the levels of species, genera/orders and functional groups. Ascomycetes dominated in less fertile forests, whereas basidiomycetes increased in abundance in more fertile forests, both in litter and humus. The relative abundance of mycorrhizal fungi in the humus layer remained high even in the most fertile soils. Tolerance to acidity and nitrogen deficiency seems to be of greater importance than plant carbon (C) allocation patterns in determining responses of fungal communities to soil fertility, in old-growth boreal forests. PMID:25952659

  9. Laccase: Microbial Sources, Production, Purification, and Potential Biotechnological Applications

    PubMed Central

    Shraddha; Shekher, Ravi; Sehgal, Simran; Kamthania, Mohit; Kumar, Ajay

    2011-01-01

    Laccase belongs to the blue multicopper oxidases and participates in cross-linking of monomers, degradation of polymers, and ring cleavage of aromatic compounds. It is widely distributed in higher plants and fungi. It is present in Ascomycetes, Deuteromycetes and Basidiomycetes and abundant in lignin-degrading white-rot fungi. It is also used in the synthesis of organic substance, where typical substrates are amines and phenols, the reaction products are dimers and oligomers derived from the coupling of reactive radical intermediates. In the recent years, these enzymes have gained application in the field of textile, pulp and paper, and food industry. Recently, it is also used in the design of biosensors, biofuel cells, as a medical diagnostics tool and bioremediation agent to clean up herbicides, pesticides and certain explosives in soil. Laccases have received attention of researchers in the last few decades due to their ability to oxidize both phenolic and nonphenolic lignin-related compounds as well as highly recalcitrant environmental pollutants. It has been identified as the principal enzyme associated with cuticular hardening in insects. Two main forms have been found: laccase-1 and laccase-2. This paper reviews the occurrence, mode of action, general properties, production, applications, and immobilization of laccases within different industrial fields. PMID:21755038

  10. Structural and functional analysis of an oligomeric hydrophobin gene from Claviceps purpurea.

    PubMed

    Mey, Géraldine; Correia, Telmo; Oeser, Birgitt; Kershaw, Michael J; Garre, Victoriano; Arntz, Claudia; Talbot, Nicholas J; Tudzynski, Paul

    2003-01-01

    SUMMARY Fungal hydrophobins are small hydrophobic proteins containing eight cysteine residues at conserved positions which have the ability to form amphipathic polymers. We have characterized a gene from the phytopathogenic ascomycete Claviceps purpurea, cpph1, which encodes a modular-type hydrophobin. It consists of five units, each showing a significant homology to class II hydrophobins. The units are separated by GN-repeat regions, which could form amphipathic alpha-helices; the amino terminus contains a glycine-rich region which could be involved in attaching the protein to the cell wall. The presence of long direct repeats within cpph1, and the high homology of the three internal modules suggest a recent generation of this gene from a tripartite precursor. Although sequencing of cDNA clones indicated that recombination could be mediated via the direct repeats, the majority of the transcripts appear to be full-sized. This was confirmed by Northern blot analysis, which showed the presence of a full-sized transcript in axenic culture. The high molecular weight pentahydrophobin was detected by Western blot analysis, indicating that CPPH1 is not processed into monomeric subunits. Targeted deletion of cpph1 did not lead to differences in morphology, growth rate, sporulation, or hydrophobicity of spores. Furthermore, the cpph1 deletion mutants showed no reduction in virulence on rye. PMID:20569360

  11. Expressed sequence tags from the flower pathogen Claviceps purpurea.

    PubMed

    Oeser, Birgitt; Beaussart, François; Haarmann, Thomas; Lorenz, Nicole; Nathues, Eva; Rolke, Yvonne; Scheffer, Jan; Weiner, January; Tudzynski, Paul

    2009-09-01

    SUMMARY The ascomycete Claviceps purpurea (ergot) is a biotrophic flower pathogen of rye and other grasses. The deleterious toxic effects of infected rye seeds on humans and grazing animals have been known since the Middle Ages. To gain further insight into the molecular basis of this disease, we generated about 10 000 expressed sequence tags (ESTs)-about 25% originating from axenic fungal culture and about 75% from tissues collected 6-20 days after infection of rye spikes. The pattern of axenic vs. in planta gene expression was compared. About 200 putative plant genes were identified within the in planta library. A high percentage of these were predicted to function in plant defence against the ergot fungus and other pathogens, for example pathogenesis-related proteins. Potential fungal pathogenicity and virulence genes were found via comparison with the pathogen-host interaction database (PHI-base; http://www.phi-base.org) and with genes known to be highly expressed in the haustoria of the bean rust fungus. Comparative analysis of Claviceps and two other fungal flower pathogens (necrotrophic Fusarium graminearum and biotrophic Ustilago maydis) highlighted similarities and differences in their lifestyles, for example all three fungi have signalling components and cell wall-degrading enzymes in their arsenal. In summary, the analysis of axenic and in planta ESTs yielded a collection of candidate genes to be evaluated for functional roles in this plant-microbe interaction. PMID:19694956

  12. CPMK2, an SLT2-homologous mitogen-activated protein (MAP) kinase, is essential for pathogenesis of Claviceps purpurea on rye: evidence for a second conserved pathogenesis-related MAP kinase cascade in phytopathogenic fungi.

    PubMed

    Mey, Géraldine; Held, Katrin; Scheffer, Jan; Tenberge, Klaus B; Tudzynski, Paul

    2002-10-01

    Cpmk2, encoding a mitogen-activated protein (MAP) kinase from the ascomycete Claviceps purpurea, is an orthologue of SLT2 from Saccharomyces cerevisiae, the first isolated from a biotrophic, non-appressorium-forming pathogen. Deletion mutants obtained by a gene replacement approach show impaired vegetative properties (no conidiation) and a significantly reduced virulence, although they retain a limited ability to colonize the host tissue. Increased sensitivity to protoplasting enzymes indicates that the cell wall structure of the mutants may be altered. As the phenotypes of these mutants are similar to those observed in strains of the rice pathogen, Magnaporthe grisea, that have been deprived of their MAP kinase gene mps1, the ability of cpmk2 to complement the defects of delta mps1 was investigated. Interestingly, the C. purpurea gene, under the control of its own promoter, was able to complement the M. grisea mutant phenotype: transformants were able to sporulate and form infection hyphae on onion epidermis and were fully pathogenic on barley leaves. This indicates that, despite the differences in infection strategies, which include host and organ specificity, mode of penetration and colonization of host tissue, CPMK2/MPS1 defines a second MAP kinase cascade (after the Fus3p/PMK1 cascade) essential for fungal pathogenicity. PMID:12406210

  13. Effector diversification within compartments of the Leptosphaeria maculans genome affected by Repeat-Induced Point mutations

    PubMed Central

    Rouxel, Thierry; Grandaubert, Jonathan; Hane, James K.; Hoede, Claire; van de Wouw, Angela P.; Couloux, Arnaud; Dominguez, Victoria; Anthouard, Véronique; Bally, Pascal; Bourras, Salim; Cozijnsen, Anton J.; Ciuffetti, Lynda M.; Degrave, Alexandre; Dilmaghani, Azita; Duret, Laurent; Fudal, Isabelle; Goodwin, Stephen B.; Gout, Lilian; Glaser, Nicolas; Linglin, Juliette; Kema, Gert H. J.; Lapalu, Nicolas; Lawrence, Christopher B.; May, Kim; Meyer, Michel; Ollivier, Bénédicte; Poulain, Julie; Schoch, Conrad L.; Simon, Adeline; Spatafora, Joseph W.; Stachowiak, Anna; Turgeon, B. Gillian; Tyler, Brett M.; Vincent, Delphine; Weissenbach, Jean; Amselem, Joëlle; Quesneville, Hadi; Oliver, Richard P.; Wincker, Patrick; Balesdent, Marie-Hélčne; Howlett, Barbara J.

    2011-01-01

    Fungi are of primary ecological, biotechnological and economic importance. Many fundamental biological processes that are shared by animals and fungi are studied in fungi due to their experimental tractability. Many fungi are pathogens or mutualists and are model systems to analyse effector genes and their mechanisms of diversification. In this study, we report the genome sequence of the phytopathogenic ascomycete Leptosphaeria maculans and characterize its repertoire of protein effectors. The L. maculans genome has an unusual bipartite structure with alternating distinct guanine and cytosine-equilibrated and adenine and thymine (AT)-rich blocks of homogenous nucleotide composition. The AT-rich blocks comprise one-third of the genome and contain effector genes and families of transposable elements, both of which are affected by repeat-induced point mutation, a fungal-specific genome defence mechanism. This genomic environment for effectors promotes rapid sequence diversification and underpins the evolutionary potential of the fungus to adapt rapidly to novel host-derived constraints. PMID:21326234

  14. The ß-importin KAP8 (Pse1/Kap121) is required for nuclear import of the cellulase transcriptional regulator XYR1, asexual sporulation and stress resistance in Trichoderma reesei

    PubMed Central

    Ghassemi, Sara; Lichius, Alexander; Bidard, Fréderique; Lemoine, Sophie; Rossignol, Marie-Noëlle; Herold, Silvia; Seidl-Seiboth, Verena; Seiboth, Bernhard; Espeso, Eduardo A; Margeot, Antoine; Kubicek, Christian P

    2015-01-01

    The ascomycete Trichoderma reesei is an industrial producer of cellulolytic and hemicellulolytic enzymes, and serves as a prime model for their genetic regulation. Most of its (hemi-)cellulolytic enzymes are obligatorily dependent on the transcriptional activator XYR1. Here, we investigated the nucleo-cytoplasmic shuttling mechanism that transports XYR1 across the nuclear pore complex. We identified 14 karyopherins in T.?reesei, of which eight were predicted to be involved in nuclear import, and produced single gene-deletion mutants of all. We found KAP8, an ortholog of Aspergillus nidulans?KapI, and Saccharomyces cerevisiae?Kap121/Pse1, to be essential for nuclear recruitment of GFP-XYR1 and cellulase gene expression. Transformation with the native gene rescued this effect. Transcriptomic analyses of ?kap8 revealed that under cellulase-inducing conditions 42 CAZymes, including all cellulases and hemicellulases known to be under XYR1 control, were significantly down-regulated. ?kap8 strains were capable of forming fertile fruiting bodies but exhibited strongly reduced conidiation both in light and darkness, and showed enhanced sensitivity towards abiotic stress, including high osmotic pressure, low pH and high temperature. Together, these data underscore the significance of nuclear import of XYR1 in cellulase and hemicellulase gene regulation in T.?reesei, and identify KAP8 as the major karyopherin required for this process. PMID:25626518

  15. Molecular systematics of the marine Dothideomycetes

    PubMed Central

    Suetrong, S.; Schoch, C.L.; Spatafora, J.W.; Kohlmeyer, J.; Volkmann-Kohlmeyer, B.; Sakayaroj, J.; Phongpaichit, S.; Tanaka, K.; Hirayama, K.; Jones, E.B.G.

    2009-01-01

    Phylogenetic analyses of four nuclear genes, namely the large and small subunits of the nuclear ribosomal RNA, transcription elongation factor 1-alpha and the second largest RNA polymerase II subunit, established that the ecological group of marine bitunicate ascomycetes has representatives in the orders Capnodiales, Hysteriales, Jahnulales, Mytilinidiales, Patellariales and Pleosporales. Most of the fungi sequenced were intertidal mangrove taxa and belong to members of 12 families in the Pleosporales: Aigialaceae, Didymellaceae, Leptosphaeriaceae, Lenthitheciaceae, Lophiostomataceae, Massarinaceae, Montagnulaceae, Morosphaeriaceae, Phaeosphaeriaceae, Pleosporaceae, Testudinaceae and Trematosphaeriaceae. Two new families are described: Aigialaceae and Morosphaeriaceae, and three new genera proposed: Halomassarina, Morosphaeria and Rimora. Few marine species are reported from the Dothideomycetidae (e.g. Mycosphaerellaceae, Capnodiales), a group poorly studied at the molecular level. New marine lineages include the Testudinaceae and Manglicola guatemalensis in the Jahnulales. Significantly, most marine Dothideomycetes are intertidal tropical species with only a few from temperate regions on salt marsh plants (Spartina species and Juncus roemerianus), and rarely totally submerged (e.g. Halotthia posidoniae and Pontoporeia biturbinata on the seagrasses Posidonia oceanica and Cymodocea nodosum). Specific attention is given to the adaptation of the Dothideomycetes to the marine milieu, new lineages of marine fungi and their host specificity. PMID:20169029

  16. Genome Sequences of Three Phytopathogenic Species of the Magnaporthaceae Family of Fungi.

    PubMed

    Okagaki, Laura H; Nunes, Cristiano C; Sailsbery, Joshua; Clay, Brent; Brown, Doug; John, Titus; Oh, Yeonyee; Young, Nelson; Fitzgerald, Michael; Haas, Brian J; Zeng, Qiandong; Young, Sarah; Adiconis, Xian; Fan, Lin; Levin, Joshua Z; Mitchell, Thomas K; Okubara, Patricia A; Farman, Mark L; Kohn, Linda M; Birren, Bruce; Ma, Li-Jun; Dean, Ralph A

    2015-01-01

    Magnaporthaceae is a family of ascomycetes that includes three fungi of great economic importance: Magnaporthe oryzae, Gaeumannomyces graminis var. tritici, and Magnaporthe poae. These three fungi cause widespread disease and loss in cereal and grass crops, including rice blast disease (M. oryzae), take-all disease in wheat and other grasses (G. graminis), and summer patch disease in turf grasses (M. poae). Here, we present the finished genome sequence for M. oryzae and draft sequences for M. poae and G. graminis var. tritici. We used multiple technologies to sequence and annotate the genomes of M. oryzae, M. poae, and G. graminis var. tritici. The M. oryzae genome is now finished to seven chromosomes whereas M. poae and G. graminis var. tritici are sequenced to 40.0× and 25.0× coverage respectively. Gene models were developed by the use of multiple computational techniques and further supported by RNAseq data. In addition, we performed preliminary analysis of genome architecture and repetitive element DNA. PMID:26416668

  17. Three common bryophilous fungi with meristematic anamorphs and phylogenetic alliance to Teratosphaeriaceae, Capnodiales.

    PubMed

    Wäli, Pauliina P; Huhtinen, Seppo; Pino-Bodas, Raquel; Stenroos, Soili

    2014-12-01

    Bryophilous ascomycetes are an overlooked and poorly known fungal group. In this study, the extreme and small-sized niche of Polytrichum piliferum hyaline leaf tips was screened for the presence of these fungi in Finland. Three closely related species were found. Bryochiton perpusillus and Bryochiton monascus were identified from several samples, and DNA isolations revealed a third closely related species, Bryochiton sp. In addition, melanised hyphae, typical to the Bryochiton species, were present in all the samples. According to phylogenetic analyses consisting of combined small subunit (SSU), large subunit (LSU), and 5.8S rDNA sequences, and internal transcribed spacer (ITS) rDNA sequences, the species showed affinity with Teratosphaeriaceae within Capnodiales, and especially with black, meristematic species often inhabiting rock substrate in extreme environments. The connection was supported by meristematic growth of the Bryochiton species in culture. Bryochiton is the second sexual genus associated within the family Teratosphaeriaceae, and B. perpusillus, and B. monascus constitute examples of teleomorphs within a group of meristematic anamorphs. These findings emphasize the multiform diversity underlying poorly researched fungal groups, such as the bryophilous fungi. PMID:25457943

  18. Isolation of the Ascobolus immersus spore color gene b2 and study in single cells of gene silencing by methylation induced premeiotically

    SciTech Connect

    Colot, V.; Rossignol, J.L.

    1995-12-01

    The ascomycete Ascobolus immersus has been extensively used as a model system for the genetic study of meiotic recombination. More recently, an epigenetic process, known as methylation induced premeiotically (MIP), that acts on duplicated sequences has been discovered in A. immersus and has raised a new interest in this fungus. To try and extend these studies, we have not cloned the A. immersus spore color gene b2, a well characterized recombination hot-spot. Isolation of the whole gene was verified by physical mapping of four large b2 alterations, followed by transformation and mutant rescue of a null b2 allele. Transformation was also used to duplicate b2 and subject it to MIP. As a result, we were able for the first time to observe gene silencing as early as just after meiosis and in single cells. Furthermore, we have found evidence for modulating effect on MIP on b2 expression, depending on the region of the gene that is duplicated and hence subjected to MIP. 48 refs., 8 figs., 2 tabs.

  19. Phospholipase A2 up-regulation during mycorrhiza formation in Tuber borchii.

    PubMed

    Miozzi, Laura; Balestrini, Raffaella; Bolchi, Angelo; Novero, Mara; Ottonello, Simone; Bonfante, Paola

    2005-07-01

    TbSP1 is a secreted and surface-associated phospholipase A(2) previously found to be up-regulated in C- or N-deprived free-living mycelia from the ectomycorrhizal ascomycete Tuber borchii. As nutrient limitation is considered an important environmental factor favouring the transition to symbiotic status, TbSP1 was suggested to be involved in the formation of mycorrhizas. An in vitro symbiosis system between Cistus incanus and T. borchii was set up: TbSP1 mRNA levels in free-living mycelia and in mycorrhizas sampled in different districts of the plant-fungus interaction were examined. In the same samples, TbSP1 protein expression was analysed by immunoelectron microscopy. A substantially enhanced TbSP1 mRNA expression, compared with nutrient-limited but free-living mycelia, was detected in the presence of the plant and reached maximal levels in fully developed mycorrhizas. A similar expression trend was revealed by immunolocalization experiments. We have shown that TbSP1 appears to respond to two partially overlapping yet distinct stimuli: nutrient starvation and mycorrhiza formation. PMID:15948845

  20. Analyses of Dynein Heavy Chain Mutations Reveal Complex Interactions Between Dynein Motor Domains and Cellular Dynein Functions

    PubMed Central

    Sivagurunathan, Senthilkumar; Schnittker, Robert R.; Razafsky, David S.; Nandini, Swaran; Plamann, Michael D.; King, Stephen J.

    2012-01-01

    Cytoplasmic dynein transports cargoes for a variety of crucial cellular functions. However, since dynein is essential in most eukaryotic organisms, the in-depth study of the cellular function of dynein via genetic analysis of dynein mutations has not been practical. Here, we identify and characterize 34 different dynein heavy chain mutations using a genetic screen of the ascomycete fungus Neurospora crassa, in which dynein is nonessential. Interestingly, our studies show that these mutations segregate into five different classes based on the in vivo localization of the mutated dynein motors. Furthermore, we have determined that the different classes of dynein mutations alter vesicle trafficking, microtubule organization, and nuclear distribution in distinct ways and require dynactin to different extents. In addition, biochemical analyses of dynein from one mutant strain show a strong correlation between its in vitro biochemical properties and the aberrant intracellular function of that altered dynein. When the mutations were mapped to the published dynein crystal structure, we found that the three-dimensional structural locations of the heavy chain mutations were linked to particular classes of altered dynein functions observed in cells. Together, our data indicate that the five classes of dynein mutations represent the entrapment of dynein at five separate points in the dynein mechanochemical and transport cycles. We have developed N. crassa as a model system where we can dissect the complexities of dynein structure, function, and interaction with other proteins with genetic, biochemical, and cell biological studies. PMID:22649085

  1. Current understanding of grapevine defense mechanisms against the biotrophic fungus (Erysiphe necator), the causal agent of powdery mildew disease

    PubMed Central

    Qiu, Wenping; Feechan, Angela; Dry, Ian

    2015-01-01

    The most economically important disease of cultivated grapevines worldwide is powdery mildew (PM) caused by the ascomycete fungus Erysiphe necator. The majority of grapevine cultivars used for wine, table grape, and dried fruit production are derived from the Eurasian grape species Vitis vinifera because of its superior aroma and flavor characteristics. However, this species has little genetic resistance against E. necator meaning that grape production is highly dependent on the frequent use of fungicides. The integration of effective genetic resistance into cultivated grapevines would lead to significant financial and environmental benefits and represents a major challenge for viticultural industries and researchers worldwide. This review will outline the strategies being used to increase our understanding of the molecular basis of V. vinifera susceptibility to this fungal pathogen. It will summarize our current knowledge of different resistance loci/genes that have evolved in wild grapevine species to restrict PM infection and assess the potential application of these defense genes in the generation of PM-resistant grapevine germplasm. Finally, it addresses future research priorities which will be important in the rapid identification, evaluation, and deployment of new PM resistance genes which are capable of conferring effective and durable resistance in the vineyard. PMID:26504571

  2. Current understanding of grapevine defense mechanisms against the biotrophic fungus (Erysiphe necator), the causal agent of powdery mildew disease.

    PubMed

    Qiu, Wenping; Feechan, Angela; Dry, Ian

    2015-01-01

    The most economically important disease of cultivated grapevines worldwide is powdery mildew (PM) caused by the ascomycete fungus Erysiphe necator. The majority of grapevine cultivars used for wine, table grape, and dried fruit production are derived from the Eurasian grape species Vitis vinifera because of its superior aroma and flavor characteristics. However, this species has little genetic resistance against E. necator meaning that grape production is highly dependent on the frequent use of fungicides. The integration of effective genetic resistance into cultivated grapevines would lead to significant financial and environmental benefits and represents a major challenge for viticultural industries and researchers worldwide. This review will outline the strategies being used to increase our understanding of the molecular basis of V. vinifera susceptibility to this fungal pathogen. It will summarize our current knowledge of different resistance loci/genes that have evolved in wild grapevine species to restrict PM infection and assess the potential application of these defense genes in the generation of PM-resistant grapevine germplasm. Finally, it addresses future research priorities which will be important in the rapid identification, evaluation, and deployment of new PM resistance genes which are capable of conferring effective and durable resistance in the vineyard. PMID:26504571

  3. A reference genetic map of Muscadinia rotundifolia and identification of Ren5, a new major locus for resistance to grapevine powdery mildew.

    PubMed

    Blanc, Sophie; Wiedemann-Merdinoglu, Sabine; Dumas, Vincent; Mestre, Pere; Merdinoglu, Didier

    2012-12-01

    Muscadinia rotundifolia, a species closely related to cultivated grapevine Vitis vinifera, is a major source of resistance to grapevine downy and powdery mildew, two major threats to cultivated traditional cultivars of V. vinifera respectively caused by the oomycete Plasmopara viticola and the ascomycete Erisyphe necator. The aim of the present work was to develop a reference genetic linkage map based on simple sequence repeat (SSR) markers for M. rotundifolia. This map was created using S1 M. rotundifolia cv. Regale progeny, and covers 948 cM on 20 linkage groups, which corresponds to the expected chromosome number for muscadine. The comparison of the genetic maps of V. vinifera and M. rotundifolia revealed a high macrosynteny between the genomes of both species. The S1 progeny was used to assess the general level of resistance of M. rotundifolia to P. viticola and E. necator, by scoring different parameters of pathogen development. A quantitative trait locus (QTL) analysis allowed us to highlight a major QTL on linkage group 14 controlling resistance to powdery mildew, which explained up to 58 % of the total phenotypic variance. This QTL was named 'Resistance to Erysiphe Necator 5' (Ren5). A microscopic evaluation E. necator mycelium development on resistant and susceptible genotypes of the S1 progeny showed that Ren5 exerts its action after the formation of the first appressorium, and acts by delaying, and then stopping, mycelium development. PMID:22865124

  4. Recruitment and interaction dynamics of plant penetration resistance components in a plasma membrane microdomain

    PubMed Central

    Bhat, Riyaz A.; Miklis, Marco; Schmelzer, Elmon; Schulze-Lefert, Paul; Panstruga, Ralph

    2005-01-01

    Many fungal pathogens must enter plant cells for successful colonization. Barley mildew resistance locus o (Mlo) is required for host cell invasion upon attack by the ascomycete powdery mildew fungus, Blumeria graminis f.sp. hordei, and encodes the founder of a family of heptahelical integral membrane proteins unique to plants. Recessively inherited loss-of-function mutant alleles (mlo) result in effective penetration resistance to all isolates of the biotrophic parasite. We used noninvasive fluorescence-based imaging to show that fluorescently tagged MLO protein becomes redistributed in the plasma membrane (PM) and accumulates beneath fungal appressoria coincident with the initiation of pathogen entry into host cells. Polarized MLO accumulation occurs once upon attack and appears to be independent of actin cytoskeleton function. Likewise, barley ROR2 syntaxin, a genetically defined component of penetration resistance to B. graminis f.sp. hordei, and a subset of predicted PM-resident proteins become redistributed to fungal entry sites. We previously identified calmodulin, a cytoplasmic calcium sensor, as an interactor and positive regulator of MLO activity and demonstrate here by FRET microscopy an increase in MLO/calmodulin FRET around penetration sites coincident with successful host cell entry. Our data provide evidence for the formation of a pathogen-triggered PM microdomain that is reminiscent of membrane microdomains (lipid rafts) induced upon attempted entry of pathogenic bacteria in animal cells. PMID:15703292

  5. Can vessel dimension explain tolerance toward fungal vascular wilt diseases in woody plants? Lessons from Dutch elm disease and esca disease in grapevine

    PubMed Central

    Pouzoulet, Jérôme; Pivovaroff, Alexandria L.; Santiago, Louis S.; Rolshausen, Philippe E.

    2014-01-01

    This review illuminates key findings in our understanding of grapevine xylem resistance to fungal vascular wilt diseases. Grapevine (Vitis spp.) vascular diseases such as esca, botryosphaeria dieback, and eutypa dieback, are caused by a set of taxonomically unrelated ascomycete fungi. Fungal colonization of the vascular system leads to a decline of the plant host because of a loss of the xylem function and subsequent decrease in hydraulic conductivity. Fungal vascular pathogens use different colonization strategies to invade and kill their host. Vitis vinifera cultivars display different levels of tolerance toward vascular diseases caused by fungi, but the plant defense mechanisms underlying those observations have not been completely elucidated. In this review, we establish a parallel between two vascular diseases, grapevine esca disease and Dutch elm disease, and argue that the former should be viewed as a vascular wilt disease. Plant genotypes exhibit differences in xylem morphology and resistance to fungal pathogens causing vascular wilt diseases. We provide evidence that the susceptibility of three commercial V. vinifera cultivars to esca disease is correlated to large vessel diameter. Additionally, we explore how xylem morphological traits related to water transport are influenced by abiotic factors, and how these might impact host tolerance of vascular wilt fungi. Finally, we explore the utility of this concept for predicting which V. vinifera cultivars are most vulnerable of fungal vascular wilt diseases and propose new strategies for disease management. PMID:24971084

  6. Horizontal transfer of a nitrate assimilation gene cluster and ecological transitions in fungi: a phylogenetic study.

    PubMed

    Slot, Jason C; Hibbett, David S

    2007-01-01

    High affinity nitrate assimilation genes in fungi occur in a cluster (fHANT-AC) that can be coordinately regulated. The clustered genes include nrt2, which codes for a high affinity nitrate transporter; euknr, which codes for nitrate reductase; and NAD(P)H-nir, which codes for nitrite reductase. Homologs of genes in the fHANT-AC occur in other eukaryotes and prokaryotes, but they have only been found clustered in the oomycete Phytophthora (heterokonts). We performed independent and concatenated phylogenetic analyses of homologs of all three genes in the fHANT-AC. Phylogenetic analyses limited to fungal sequences suggest that the fHANT-AC has been transferred horizontally from a basidiomycete (mushrooms and smuts) to an ancestor of the ascomycetous mold Trichoderma reesei. Phylogenetic analyses of sequences from diverse eukaryotes and eubacteria, and cluster structure, are consistent with a hypothesis that the fHANT-AC was assembled in a lineage leading to the oomycetes and was subsequently transferred to the Dikarya (Ascomycota+Basidiomycota), which is a derived fungal clade that includes the vast majority of terrestrial fungi. We propose that the acquisition of high affinity nitrate assimilation contributed to the success of Dikarya on land by allowing exploitation of nitrate in aerobic soils, and the subsequent transfer of a complete assimilation cluster improved the fitness of T. reesei in a new niche. Horizontal transmission of this cluster of functionally integrated genes supports the "selfish operon" hypothesis for maintenance of gene clusters. PMID:17971860

  7. Two major facilitator superfamily sugar transporters from Trichoderma reesei and their roles in induction of cellulase biosynthesis.

    PubMed

    Zhang, Weixin; Kou, Yanbo; Xu, Jintao; Cao, Yanli; Zhao, Guolei; Shao, Jing; Wang, Hai; Wang, Zhixing; Bao, Xiaoming; Chen, Guanjun; Liu, Weifeng

    2013-11-15

    Proper perception of the extracellular insoluble cellulose is key to initiating the rapid synthesis of cellulases by cellulolytic Trichoderma reesei. Uptake of soluble oligosaccharides derived from cellulose hydrolysis represents a potential point of control in the induced cascade. In this study, we identified a major facilitator superfamily sugar transporter Stp1 capable of transporting cellobiose by reconstructing a cellobiose assimilation system in Saccharomyces cerevisiae. The absence of Stp1 in T. reesei resulted in differential cellulolytic response to Avicel versus cellobiose. Transcriptional profiling revealed a different expression profile in the ?stp1 strain from that of wild-type strain in response to Avicel and demonstrated that Stp1 somehow repressed induction of the bulk of major cellulase and hemicellulose genes. Two other putative major facilitator superfamily sugar transporters were, however, up-regulated in the profiling. Deletion of one of them identified Crt1 that was required for growth and enzymatic activity on cellulose or lactose, but was not required for growth or hemicellulase activity on xylan. The essential role of Crt1 in cellulase induction did not seem to rely on its transporting activity because the overall uptake of cellobiose or sophorose by T. reesei was not compromised in the absence of Crt1. Phylogenetic analysis revealed that orthologs of Crt1 exist in the genomes of many filamentous ascomycete fungi capable of degrading cellulose. These data thus shed new light on the mechanism by which T. reesei senses and transmits the cellulose signal and offers potential strategies for strain improvement. PMID:24085297

  8. Occurrence of Scopulariopsis and Scedosporium in nails and keratinous skin. A 5-year retrospective multi-center study.

    PubMed

    Issakainen, Jouni; Heikkilä, Hannele; Vainio, Eeva; Koukila-Kähkölä, Pirkko; Castren, Mirja; Liimatainen, Oili; Ojanen, Tarja; Koskela, Markku; Meurman, Olli

    2007-05-01

    A 5-year retrospective multicenter study was performed for microascaceous moulds (Microascaceae, Ascomycetes) in Finnish clinical specimens. The files from 1993-1997 of six clinical mycology laboratories in Finland were searched for reports of these fungi, mainly Scopulariopsis and Scedosporium anamorphs in keratinous specimens. From the 521 primary findings, 165 cases were selected for further study based on direct microscopy, colony numbers and accompanying fungi. The clinical records of 148 cases (141 Scopulariopsis, 7 Scedosporium) were studied. Of the nail infections from which Scopulariopsis was recovered, 39 cases were further separated which showed clinical or laboratory-based evidence of dermatophytosis. In the remaining 90 'non-dermatophyte' nail cases, Scopulariopsis spp. were the only documented fungal agents (c. 6 cases/million/year). The patients were mainly elderly, 66% of whom had problems involving their big toe nails. For 74% of them, the nail problem was mentioned as their reason for visiting the physician. However, only 18% had documented benefit from treatment. The Scopulariopsis nail infections seem to be treatment-resistant and the pathogenesis and etiological role of Scopulariopsis remain poorly understood. PMID:17464841

  9. De novo genome assembly of the soil-borne fungus and tomato pathogen Pyrenochaeta lycopersici

    PubMed Central

    2014-01-01

    Background Pyrenochaeta lycopersici is a soil-dwelling ascomycete pathogen that causes corky root rot disease in tomato (Solanum lycopersicum) and other Solanaceous crops, reducing fruit yields by up to 75%. Fungal pathogens that infect roots receive less attention than those infecting the aerial parts of crops despite their significant impact on plant growth and fruit production. Results We assembled a 54.9Mb P. lycopersici draft genome sequence based on Illumina short reads, and annotated approximately 17,000 genes. The P. lycopersici genome is closely related to hemibiotrophs and necrotrophs, in agreement with the phenotypic characteristics of the fungus and its lifestyle. Several gene families related to host–pathogen interactions are strongly represented, including those responsible for nutrient absorption, the detoxification of fungicides and plant cell wall degradation, the latter confirming that much of the genome is devoted to the pathogenic activity of the fungus. We did not find a MAT gene, which is consistent with the classification of P. lycopersici as an imperfect fungus, but we observed a significant expansion of the gene families associated with heterokaryon incompatibility (HI). Conclusions The P. lycopersici draft genome sequence provided insight into the molecular and genetic basis of the fungal lifestyle, characterizing previously unknown pathogenic behaviors and defining strategies that allow this asexual fungus to increase genetic diversity and to acquire new pathogenic traits. PMID:24767544

  10. Ectomycorrhizal Inocybe species associate with the mycoheterotrophic orchid Epipogium aphyllum but not its asexual propagules

    PubMed Central

    Roy, Melanie; Yagame, Takahiro; Yamato, Masahide; Iwase, Koji; Heinz, Christine; Faccio, Antonella; Bonfante, Paola; Selosse, Marc-Andre

    2009-01-01

    Background and Aims Epipogium aphyllum is a Eurasian achlorophyllous, mycoheterotrophic forest orchid. Due to its rarity, it is often protected, and its biology is poorly known. The identity and pattern of colonization of fungal associates providing carbon to this orchid have not been studied previously. Methods Using samples from 34 individuals from 18 populations in Japan, Russia and France, the following were investigated: (a) colonization patterns of fungal associates of E. aphyllum by microscopy; (b) their identity by PCR amplification of nuclear ribosomal ITS carried out on rhizome fragments and hyphal pelotons. Results and Conclusions Microscopic investigations revealed that thick rhizomes were densely colonized by fungi bearing clamp-connections and dolipores, i.e. basidiomycetes. Molecular analysis identified Inocybe species as exclusive symbionts of 75 % of the plants investigated and, more rarely, other basidiomycetes (Hebeloma, Xerocomus, Lactarius, Thelephora species). Additionally, ascomycetes, probably endophytes or parasites, were sometimes present. Although E. aphyllum associates with diverse species from Inocybe subgenera Mallocybe and Inocybe sensu stricto, no evidence for cryptic speciation in E. aphyllum was found. Since basidiomycetes colonizing the orchid are ectomycorrhizal, surrounding trees are probably the ultimate carbon source. Accordingly, in one population, ectomycorrhizae sampled around an individual orchid revealed the same fungus on 11·2 % of tree roots investigated. Conversely, long, thin stolons bearing bulbils indicated active asexual multiplication, but these propagules were not colonized by fungi. These findings are discussed in the framework of ecology and evolution of mycoheterotrophy. PMID:19155220

  11. Ectomycorrhizal fungi associated with two species of Kobresia in an alpine meadow in the eastern Himalaya.

    PubMed

    Gao, Qian; Yang, Zhu L

    2010-04-01

    The diversity of ectomycorrhizal fungi (EMF) on Kobresia filicina and Kobresia capillifolia in an alpine meadow in China's southwestern mountains, one of the word's hotspots of biodiversity, was estimated based on internal transcribed spacer rDNA sequence analysis of root tips. Seventy EMF operational taxonomical units (OTUs) were found in the two plant species. Dauciform roots with EMF were detected in species of Kobresia for the first time. OTU richness of EMF was high in Tomentella/Thelophora and Inocybe, followed by Cortinarius, Sebacina, the Cenococcum geophilum complex, and Russula. Tomentella/Thelophora and Inocybe were general and dominant mycobiont genera of the two sedges. Besides the C. geophilum complex, the ascomycete components Hymenoscyphus and Lachnum were also detected on the two plants. Alpine plants in different geographical regions share similar main genera and/or families of EMF while harboring predominantly different mycobiont species; most of the members detected by us have not been found elsewhere. Significant differences in the profile of EMF occurrences were not found between the two plant species and among the three sampling seasons in our sample size. PMID:20012655

  12. Efficiency of uronic acid uptake in marine alginate-degrading fungi

    NASA Astrophysics Data System (ADS)

    Schaumann, K.; Weide, G.

    1995-03-01

    Despite the fact that many marine fungi, including phycomycetes, yeasts, ascomycetes and hyphomycetes, have been recorded from living and/or dead phaeophytes, only a few of these have been shown to be capable of degrading alginic acid or alginates. The degradation is achieved by the action of an exoenzyme complex, comprising alginate lyase, as well as alginate hydrolase activities. The latter was detected only recently by the authors. In this study, the growth of two marine sodiumalginate-degrading deuteromycetes, Asteromyces cruciatus and Dendryphiella salina, was investigated, and the assimilation efficiency of sodiumalginate and its uronic acid degradation products, respectively, was estimated from the economic coefficient (E). E is calculated from the mycelial dry weight, divided by the weight of substrate consumed for this production. The economic coefficient for A. cruciatus was 48.6%, and that of D. salina 38.9%. This indicates that the former species uses the alginate degradation products more efficiently than the latter. The observed E-values for the marine deuteromycetes agree with those from other fungi, e.g. terrestrial species. In general, it is concluded that the marine fungi appear to play a more important role in kelp-based ecosystems than was realized previously.

  13. Molecular systematics of the marine Dothideomycetes.

    PubMed

    Suetrong, S; Schoch, C L; Spatafora, J W; Kohlmeyer, J; Volkmann-Kohlmeyer, B; Sakayaroj, J; Phongpaichit, S; Tanaka, K; Hirayama, K; Jones, E B G

    2009-01-01

    Phylogenetic analyses of four nuclear genes, namely the large and small subunits of the nuclear ribosomal RNA, transcription elongation factor 1-alpha and the second largest RNA polymerase II subunit, established that the ecological group of marine bitunicate ascomycetes has representatives in the orders Capnodiales, Hysteriales, Jahnulales, Mytilinidiales, Patellariales and Pleosporales. Most of the fungi sequenced were intertidal mangrove taxa and belong to members of 12 families in the Pleosporales: Aigialaceae, Didymellaceae,Leptosphaeriaceae, Lenthitheciaceae, Lophiostomataceae, Massarinaceae,Montagnulaceae, Morosphaeriaceae, Phaeosphaeriaceae, Pleosporaceae, Testudinaceae and Trematosphaeriaceae. Two new families are described: Aigialaceae and Morosphaeriaceae, and three new genera proposed: Halomassarina, Morosphaeria and Rimora. Few marine species are reported from the Dothideomycetidae (e.g. Mycosphaerellaceae, Capnodiales), a group poorly studied at the molecular level. New marine lineages include the Testudinaceae and Manglicolaguatemalensis in the Jahnulales. Significantly, most marine Dothideomycetes are intertidal tropical species with only a few from temperate regions on salt marsh plants (Spartina species and Juncus roemerianus), and rarely totally submerged (e.g. Halotthia posidoniae and Pontoporeia biturbinata on the seagrasses Posidonia oceanica and Cymodocea nodosum). Specific attention is given to the adaptation of the Dothideomycetes to the marine milieu, new lineages of marine fungi and their host specificity. PMID:20169029

  14. Multiple markers pyrosequencing reveals highly diverse and host-specific fungal communities on the mangrove trees Avicennia marina and Rhizophora stylosa.

    PubMed

    Arfi, Yonathan; Buée, Marc; Marchand, Cyril; Levasseur, Anthony; Record, Eric

    2012-02-01

    Fungi are important actors in ecological processes and trophic webs in mangroves. Although saprophytic fungi occurring in the intertidal part of mangrove have been well studied, little is known about the diversity and structure of the fungal communities in this ecosystem or about the importance of functional groups like pathogens and mutualists. Using tag-encoded 454 pyrosequencing of the ITS1, ITS2, nu-ssu-V5 and nu-ssu-V7 regions, we studied and compared the fungal communities found on the marine and aerial parts of Avicennia marina and Rhizophora stylosa trees in a mangrove in New Caledonia. A total of 209,544 reads were analysed, corresponding to several thousand molecular operational taxonomic units (OTU). There is a marked zonation in the species distribution, with most of the OTU being found specifically in one of the microhabitat studied. Ascomycetes are the dominant phylum (82%), Basidiomycetes are very rare (3%), and 15% of the sequences correspond to unknown taxa. Our results indicate that host specificity is a key factor in the distribution of the highly diverse fungal communities, in both the aerial and intertidal parts of the trees. This study also validates the usefulness of multiple markers in tag-encoded pyrosequencing to consolidate and refine the assessment of the taxonomic diversity. PMID:22092266

  15. Novel aspects in the life cycle and biotrophic interactions in Pezizomycetes (Ascomycota, Fungi).

    PubMed

    Tedersoo, Leho; Arnold, A Elizabeth; Hansen, Karen

    2013-03-01

    The ascomycete class Pezizomycetes (single order Pezizales)is known for its cup-shaped fruit bodies and the evolution of edible truffles and morels, but little is known about the ontogeny and ecology of this large and ecologically diverse fungal group. In this issue of Molecular Ecology, Healy et al. (2013) make a great leap forward by describing and identifying asexual, anamorphic structures that produce mitotic spores in many ectomycorrhiza-forming truffle and nontruffle species on soil surfaces worldwide(Fig. 1). Although such anamorphic forms have been reported sporadically from certain ectomycorrhizal and saprotrophic Pezizomycetes (e.g. Warcup 1990), Healy et al. (2013) demonstrate that these terricolous asexual forms are both taxonomically and geographically more widespread and, in fact, much more common than previously understood. We anticipate that deeper insight into other substrates, provided by molecular analyses of materials such as dead wood and seeds, is likely to reveal numerous anamorphs of saprotrophic and pathogenic Pezizomycetes as well (see Marek et al. 2009). PMID:23599958

  16. Mitigation of antagonistic effects on plant growth due to root co-colonization by dark septate endophytes and ectomycorrhiza.

    PubMed

    Reininger, Vanessa; Sieber, Thomas N

    2013-12-01

    Dark septate endophytes (DSE) are very common root colonizers of woody plant species. Ascomycetes of the Phialocephala fortinii s.l.-Acephala applanata species complex (PAC) are the main representatives of DSE fungi in forest ecosystems. PAC and mycorrhizal fungi share the same habitat, but interactions among PAC, mycorrhizal fungi and plants are poorly understood. We compared the effects of single and dual inoculation of Norway spruce seedlings with PAC and the ectomycorrhizal (ECM) fungus Hebeloma crustuliniforme on host growth, degree of mycorrhization and density of endophytic PAC biomass. Single colonization by H.?crustuliniforme or PAC significantly reduced plant biomass. Dual colonization reduced or neutralized plant growth depression caused by single fungal colonization. The degree of mycorrhization was independent on PAC colonization, and mycorrhization significantly reduced endophytic PAC biomass. Plant biomass of dually colonized plants positively correlated with PAC biomass. These results demonstrate the ability of dual inoculation of PAC and H.?crustuliniforme to neutralize plant growth depression caused by single fungal inoculation. Our explanations of enhanced plant growth in dually inoculated plants are the inhibition of PAC during root colonization by the ECM mantle and ECM-mediated access to plant growth-promoting nutrients resulting from the mineralization of the potting medium by PAC. PMID:24249297

  17. Sugar transporters in the black truffle Tuber melanosporum: from gene prediction to functional characterization.

    PubMed

    Ceccaroli, Paola; Saltarelli, Roberta; Polidori, Emanuela; Barbieri, Elena; Guescini, Michele; Ciacci, Caterina; Stocchi, Vilberto

    2015-08-01

    In a natural forest ecosystem, ectomycorrhiza formation is a way for soil fungi to obtain carbohydrates from their host plants. However, our knowledge of sugar transporters in ectomycorrhizal ascomycetous fungi is limited. To bridge this gap we used data obtained from the sequenced genome of the ectomycorrhizal fungus Tuber melanosporum Vittad. to search for sugar transporters. Twenty-three potential hexose transporters were found, and three of them (Tmelhxt1, Tmel2281 and Tmel131), differentially expressed during the fungus life cycle, were investigated. The heterologous expression of Tmelhxt1 and Tmel2281 in an hxt-null Saccharomyces cerevisiae strain restores the growth in glucose and fructose. The functional characterization and expression profiles of Tmelhxt1 and Tmel2281 in the symbiotic phase suggest that they are high affinity hexose transporters at the plant-fungus interface. On the contrary, Tmel131 is preferentially expressed in the fruiting body and its inability to restore the S. cerevisiae mutant strain growth led us to hypothesize that it could be involved in the transport of alternative carbon sources important for a hypothetical saprophytic strategy for the complete maturation of the carpophore. PMID:26021705

  18. Expanding genomics of mycorrhizal symbiosis

    PubMed Central

    Kuo, Alan; Kohler, Annegret; Martin, Francis M.; Grigoriev, Igor V.

    2014-01-01

    The mycorrhizal symbiosis between soil fungi and plant roots is a ubiquitous mutualism that plays key roles in plant nutrition, soil health, and carbon cycling. The symbiosis evolved repeatedly and independently as multiple morphotypes [e.g., arbuscular mycorrhizae (AM), ectomycorrhizal (ECM)] in multiple fungal clades (e.g., phyla Glomeromycota, Ascomycota, Basidiomycota). The accessibility and cultivability of many mycorrhizal partners make them ideal models for symbiosis studies. Alongside molecular, physiological, and ecological investigations, sequencing led to the first three mycorrhizal fungal genomes, representing two morphotypes and three phyla. The genome of the ECM basidiomycete Laccaria bicolor showed that the mycorrhizal lifestyle can evolve through loss of plant cell wall-degrading enzymes (PCWDEs) and expansion of lineage-specific gene families such as short secreted protein (SSP) effectors. The genome of the ECM ascomycete Tuber melanosporum showed that the ECM type can evolve without expansion of families as in Laccaria, and thus a different set of symbiosis genes. The genome of the AM glomeromycete Rhizophagus irregularis showed that despite enormous phylogenetic distance and morphological difference from the other two fungi, symbiosis can involve similar solutions as symbiosis-induced SSPs and loss of PCWDEs. The three genomes provide a solid base for addressing fundamental questions about the nature and role of a vital mutualism. PMID:25408690

  19. Leotia cf. lubrica forms arbutoid mycorrhiza with Comarostaphylis arbutoides (Ericaceae).

    PubMed

    Kühdorf, Katja; Münzenberger, B; Begerow, D; Gómez-Laurito, J; Hüttl, R F

    2015-02-01

    Arbutoid mycorrhizal plants are commonly found as understory vegetation in forests worldwide where ectomycorrhiza-forming trees occur. Comarostaphylis arbutoides (Ericaceae) is a tropical woody plant and common in tropical Central America. This plant forms arbutoid mycorrhiza, whereas only associations with Leccinum monticola as well as Sebacina sp. are described so far. We collected arbutoid mycorrhizas of C. arbutoides from the Cerro de la Muerte (Cordillera de Talamanca), Costa Rica, where this plant species grows together with Quercus costaricensis. We provide here the first evidence of mycorrhizal status for the Ascomycete Leotia cf. lubrica (Helotiales) that was so far under discussion as saprophyte or mycorrhizal. This fungus formed arbutoid mycorrhiza with C. arbutoides. The morphotype was described morphologically and anatomically. Leotia cf. lubrica was identified using molecular methods, such as sequencing the internal-transcribed spacer (ITS) and the large subunit (LSU) ribosomal DNA regions, as well as phylogenetic analyses. Specific plant primers were used to confirm C. arbutoides as the host plant of the leotioid mycorrhiza. PMID:25033922

  20. Fungal biosynthesis of the bibenzoquinone oosporein to evade insect immunity.

    PubMed

    Feng, Peng; Shang, Yanfang; Cen, Kai; Wang, Chengshu

    2015-09-01

    Quinones are widely distributed in nature and exhibit diverse biological or pharmacological activities; however, their biosynthetic machineries are largely unknown. The bibenzoquinone oosporein was first identified from the ascomycete insect pathogen Beauveria bassiana>50 y ago. The toxin can also be produced by different plant pathogenic and endophytic fungi with an array of biological activities. Here, we report the oosporein biosynthetic machinery in fungi, a polyketide synthase (PKS) pathway including seven genes for quinone biosynthesis. The PKS oosporein synthase 1 (OpS1) produces orsellinic acid that is hydroxylated to benzenetriol by the hydroxylase OpS4. The intermediate is oxidized either nonenzymatically to 5,5'-dideoxy-oosporein or enzymatically to benzenetetrol by the putative dioxygenase OpS7. The latter is further dimerized to oosporein by the catalase OpS5. The transcription factor OpS3 regulates intrapathway gene expression. Insect bioassays revealed that oosporein is required for fungal virulence and acts by evading host immunity to facilitate fungal multiplication in insects. These results contribute to the known mechanisms of quinone biosynthesis and the understanding of small molecules deployed by fungi that interact with their hosts. PMID:26305932

  1. Deletion and Complementation of the Mating Type (MAT) Locus of the Wheat Head Blight Pathogen Gibberella zeae

    PubMed Central

    Desjardins, A. E.; Brown, D. W.; Yun, S.-H.; Proctor, R. H.; Lee, T.; Plattner, R. D.; Lu, S.-W.; Turgeon, B. G.

    2004-01-01

    Gibberella zeae, a self-fertile, haploid filamentous ascomycete, causes serious epidemics of wheat (Triticum aestivum) head blight worldwide and contaminates grain with trichothecene mycotoxins. Anecdotal evidence dating back to the late 19th century indicates that G. zeae ascospores (sexual spores) are a more important inoculum source than are macroconidia (asexual spores), although the fungus can produce both during wheat head blight epidemics. To develop fungal strains to test this hypothesis, the entire mating type (MAT1) locus was deleted from a self-fertile (MAT1-1/MAT1-2), virulent, trichothecene-producing wild-type strain of G. zeae. The resulting MAT deletion (mat1-1/mat1-2) strains were unable to produce perithecia or ascospores and appeared to be unable to mate with the fertile strain from which they were derived. Complementation of a MAT deletion strain by transformation with a copy of the entire MAT locus resulted in recovery of production of perithecia and ascospores. MAT deletion strains and MAT-complemented strains retained the ability to produce macroconidia that could cause head blight, as assessed by direct injection into wheat heads in greenhouse tests. Availability of MAT-null and MAT-complemented strains provides a means to determine the importance of ascospores in the biology of G. zeae and perhaps to identify novel approaches to control wheat head blight. PMID:15066842

  2. Clustering of Two Genes Putatively Involved in Cyanate Detoxification Evolved Recently and Independently in Multiple Fungal Lineages

    PubMed Central

    Elmore, M. Holly; McGary, Kriston L.; Wisecaver, Jennifer H.; Slot, Jason C.; Geiser, David M.; Sink, Stacy; O’Donnell, Kerry; Rokas, Antonis

    2015-01-01

    Fungi that have the enzymes cyanase and carbonic anhydrase show a limited capacity to detoxify cyanate, a fungicide employed by both plants and humans. Here, we describe a novel two-gene cluster that comprises duplicated cyanase and carbonic anhydrase copies, which we name the CCA gene cluster, trace its evolution across Ascomycetes, and examine the evolutionary dynamics of its spread among lineages of the Fusarium oxysporum species complex (hereafter referred to as the FOSC), a cosmopolitan clade of purportedly clonal vascular wilt plant pathogens. Phylogenetic analysis of fungal cyanase and carbonic anhydrase genes reveals that the CCA gene cluster arose independently at least twice and is now present in three lineages, namely Cochliobolus lunatus, Oidiodendron maius, and the FOSC. Genome-wide surveys within the FOSC indicate that the CCA gene cluster varies in copy number across isolates, is always located on accessory chromosomes, and is absent in FOSC’s closest relatives. Phylogenetic reconstruction of the CCA gene cluster in 163 FOSC strains from a wide variety of hosts suggests a recent history of rampant transfers between isolates. We hypothesize that the independent formation of the CCA gene cluster in different fungal lineages and its spread across FOSC strains may be associated with resistance to plant-produced cyanates or to use of cyanate fungicides in agriculture. PMID:25663439

  3. [Cryphonectria parasitica as a host of fungal viruses: a tool useful to unravel the mycovirus world].

    PubMed

    Suzuki, Nobuhiro

    2014-01-01

    There appear to be over a million of fungal species including those that have been unidentified and unreported, where a variety of viruses make a world as well. Studies on a very small number of them conducted during the last two decades demonstrated the infectivity of fungal viruses that had previously been assumed to be inheritable, indigenus and non-infectious. Also, great technical advances were achieved. The chest blight fungus (Cryphonectria parasitica), a phytopathogenic ascomycetous fungus, has emerged as a model filamentous fungus for fungal virology. The genome sequence with annotations, albeit not thorough, many useful research tools, and gene manipulation technologies are available for this fungus. Importantly, C. parasitica can support replication of homologous viruses naturally infecting it, in addition to heterologous viruses infecting another plant pathogenic fungus, Rosellinia necatrix taxonomically belonging to a different order. In this article, I overview general properties of fungal viruses and advantages of the chestnut blight fungus as a mycovirus host. Furthermore, I introduce two recent studies carried out using this fungal host:''Defective interfering RNA and RNA silencing that regulate the replication of a partitivirus'' and'' RNA silencing and RNA recombination''. PMID:25765976

  4. Viruses of the white root rot fungus, Rosellinia necatrix.

    PubMed

    Kondo, Hideki; Kanematsu, Satoko; Suzuki, Nobuhiro

    2013-01-01

    Rosellinia necatrix is a filamentous ascomycete that is pathogenic to a wide range of perennial plants worldwide. An extensive search for double-stranded RNA of a large collection of field isolates led to the detection of a variety of viruses. Since the first identification of a reovirus in this fungus in 2002, several novel viruses have been molecularly characterized that include members of at least five virus families. While some cause phenotypic alterations, many others show latent infections. Viruses attenuating the virulence of a host fungus to its plant hosts attract much attention as agents for virocontrol (biological control using viruses) of the fungus, one of which is currently being tested in experimental fields. Like the Cryphonectria parasitica/viruses, the R. necatrix/viruses have emerged as an amenable system for studying virus/host and virus/virus interactions. Several techniques have recently been developed that enhance the investigation of virus etiology, replication, and symptom induction in this mycovirus/fungal host system. PMID:23498907

  5. Verticillium systematics and evolution: how confusion impedes Verticillium wilt management and how to resolve it.

    PubMed

    Inderbitzin, Patrik; Subbarao, Krishna V

    2014-06-01

    Verticillium wilts are important vascular wilt diseases that affect many crops and ornamentals in different regions of the world. Verticillium wilts are caused by members of the ascomycete genus Verticillium, a small group of 10 species that are related to the agents of anthracnose caused by Colletotrichum species. Verticillium has a long and complicated taxonomic history with controversies about species boundaries and long overlooked cryptic species, which confused and limited our knowledge of the biology of individual species. We first review the taxonomic history of Verticillium, provide an update and explanation of the current system of classification and compile host range and geographic distribution data for individual species from internal transcribed spacer (ITS) GenBank records. Using Verticillium as an example, we show that species names are a poor vehicle for archiving and retrieving information, and that species identifications should always be backed up by DNA sequence data and DNA extracts that are made publicly available. If such a system were made a prerequisite for publication, all species identifications could be evaluated retroactively, and our knowledge of the biology of individual species would be immune from taxonomic changes, controversy and misidentification. Adoption of this system would improve quarantine practices and the management of diseases caused by various plant pathogens. PMID:24548214

  6. [Diversity and community structure of endophytic fungi from Taxus chinensis var. mairei].

    PubMed

    2014-07-01

    A total of 628 endophytic fungi were isolated from 480 tissue segments of needles and branches of Taxus chinensis var. mairei. According to morphological characteristics and ITS sequences, they represented 43 taxa in 28 genera, of which 10 Hyphomycetes, 20 Coelomycetes, 12 Ascomycetes and 1 unknown fungus. Phomopsis mali was confirmed as the dominant species. In accordance with relative frequency, Alternaria alternata, Aureobasidium pullulans, Colletotrichum boninense, C. gloeosporioides, Epicoccum nigrum , Fungal sp., Fusarium lateritium, Glomerella cingulata, Magnaporthales sp. , Nigrospora oryzae, Pestalotiopsis maculiformans, P. microspora, Peyronellaea glomerata and Xylaria sp. 1 were more common in T. chinensis var. mairei. T. chinensis var. mairei were severely infected by endophytic fungi. Endophytic fungi were found in 81 percent of plant tissues with a high diversity. Distribution ranges of endophytic fungi were influenced by tissue properties. The colonization rate, richness, diversity of endophytic fungi in needles were obviously lower than in branches, and kinds of endophytic fungi between branches were more similar than those in needles, thus endophytic fungi had tissue preference. In addition, tissue age influenced the community structure of endophytic fungi. The elder branch tissues were, the higher colonization rate, richness, diversity of endophytic fungi were. Systematic studying the diversity and community structure of endophytic fungi in T. chinensis var. mairei and clarifying their distribution regularity in plant tissues would offer basic data and scientific basis for their development and utilization. Discussing the presence of fungal pathogens in healthy plant tissues would be of positive significance for source protection of T. chinensis var. mairei. PMID:25345060

  7. A Role of AREB in the Regulation of PACC-Dependent Acid-Expressed-Genes and Pathogenicity of Colletotrichum gloeosporioides.

    PubMed

    Ment, Dana; Alkan, Noam; Luria, Neta; Bi, Fang-Cheng; Reuveni, Eli; Fluhr, Robert; Prusky, Dov

    2015-02-01

    Gene expression regulation by pH in filamentous fungi and yeasts is controlled by the PACC/RIM101 transcription factor. In Colletotrichum gloeosporioides, PACC is known to act as positive regulator of alkaline-expressed genes, and this regulation was shown to contribute to fungal pathogenicity. PACC is also a negative regulator of acid-expressed genes, however; the mechanism of downregulation of acid-expressed genes by PACC and their contribution to C. gloeosporioides pathogenicity is not well understood. RNA sequencing data analysis was employed to demonstrate that PACC transcription factor binding sites (TFBS) are significantly overrepresented in the promoter of PACC-upregulated, alkaline-expressed genes. In contrast, they are not overrepresented in the PACC-downregulated, acid-expressed genes. Instead, acid-expressed genes showed overrepresentation of AREB GATA TFBS in C. gloeosporioides and in homologs of five other ascomycetes genomes. The areB promoter contains PACC TFBS; its transcript was upregulated at pH 7 and repressed in ?pacC. Furthermore, acid-expressed genes were found to be constitutively upregulated in ?areB during alkalizing conditions. The areB mutants showed significantly reduced ammonia secretion and pathogenicity on tomato fruit. Present results indicate that PACC activates areB expression, thereby conditionally repressing acid-expressed genes and contributing critically to C. gloeosporioides pathogenicity. PMID:25317668

  8. Phospho-Regulation of the Neurospora crassa Septation Initiation Network

    PubMed Central

    Heilig, Yvonne; Schmitt, Kerstin; Seiler, Stephan

    2013-01-01

    Proper cell division is essential for growth and development of uni- and multicellular organisms. The fungal septation initiation network (SIN) functions as kinase cascade that connects cell cycle progression with the initiation of cytokinesis. Miss-regulation of the homologous Hippo pathway in animals results in excessive cell proliferation and formation of tumors, underscoring the conservation of both pathways. How SIN proteins interact and transmit signals through the cascade is only beginning to be understood. Moreover, our understanding of septum formation and its regulation in filamentous fungi, which represent the vast majority of the fungal kingdom, is highly fragmentary. We determined that a tripartite kinase cascade, consisting of CDC-7, SID-1 and DBF-2, together with their regulatory subunits CDC-14 and MOB-1, is important for septum formation in the model mold Neurospora crassa. DBF-2 activity and septum formation requires auto-phosphorylation at Ser499 within the activation segment and phosphorylation of Thr671 in the hydrophobic motif by SID-1. Moreover, SID-1-stimulated DBF-2 activity is further enhanced by CDC-7, supporting a stepwise activation mechanism of the tripartite SIN kinase cascade in fungi. However, in contrast to the situation described for unicellular yeasts, the localization of the entire SIN cascade to spindle pole bodies is constitutive and cell cycle independent. Moreover, all SIN proteins except CDC-7 form cortical rings prior to septum initiation and localize to constricting septa. Thus, SIN localization and activity regulation significantly differs in unicellular versus syncytial ascomycete fungi. PMID:24205386

  9. Molecular Phylogenetic Analysis Reveals the New Genus Hemisphaericaspora of the Family Debaryomycetaceae

    PubMed Central

    Hui, Fengli; Ren, Yongcheng; Chen, Liang; Li, Ying; Zhang, Lin; Niu, Qiuhong

    2014-01-01

    Four strains of a novel ascomycetous yeast species were recovered from the frass of wood-boring beetles collected from the Baotianman Nature Reserve and the Laojieling Nature Reserve in Henan Province, China. This species produced unconjugated and deliquescent asci with hemispheroid or helmet-shaped ascospores. Analysis of gene sequences for the D1/D2 domain of the large subunit (LSU) rRNA, as well as analysis of concatenated gene sequences for the nearly complete small subunit (SSU) rRNA and D1/D2 domain of the large subunit (LSU) rRNA placed the novel species in a small clade including only one recognised species, Candida insectamans, in the family Debaryomycetaceae (Saccharomycotina, Ascomycota). DNA sequence analyses demonstrated that the novel species was distinct from all currently recognised teleomorphic yeast genus. The name Hemisphaericaspora nanyangensis gen nov., sp. nov. is proposed to accommodate the novel genus and species. The new genus can be distinguished from closely related teleomorphic genera Lodderomyces and Spathaspora through sequence comparison and ascospore morphology. The ex-type strain of H. nanyangensis is CBS 13020T (?=?CICC 33021?=?NYNU 13717). Furthermore, based on phenotypic and genotypic characteristics, C. insectamans is transferred to the newly described genus as Hemisphaericaspora insectamans comb. nov., in accordance with the changes in the International Code of Nomenclature for algae, fungi and plants. PMID:25075963

  10. Development of a rapid multiplex SSR genotyping method to study populations of the fungal plant pathogen Zymoseptoria tritici

    PubMed Central

    2014-01-01

    Background Zymoseptoria tritici is a hemibiotrophic ascomycete fungus causing leaf blotch of wheat that often decreases yield severely. Populations of the fungus are known to be highly diverse and poorly differentiated from each other. However, a genotyping tool is needed to address further questions in large collections of isolates, regarding regional population structure, adaptation to anthropogenic selective pressures, and dynamics of the recently discovered accessory chromosomes. This procedure is limited by costly and time-consuming simplex PCR genotyping. Recent development of genomic approaches and of larger sets of SSRs enabled the optimization of microsatellite multiplexing. Findings We report here a reliable protocol to amplify 24 SSRs organized in three multiplex panels, and covering all Z. tritici chromosomes. We also propose an automatic allele assignment procedure, which allows scoring alleles in a repeatable manner across studies and laboratories. All together, these tools enabled us to characterize local and worldwide populations and to calculate diversity indexes consistent with results reported in the literature. Conclusion This easy-to-use, accurate, repeatable, economical, and faster technical strategy can provide useful genetic information for evolutionary inferences concerning Z. tritici populations. Moreover, it will facilitate the comparison of studies from different scientific groups. PMID:24943709

  11. Paralog Re-Emergence: A Novel, Historically Contingent Mechanism in the Evolution of Antimicrobial Resistance

    PubMed Central

    Hawkins, Nichola J.; Cools, Hans J.; Sierotzki, Helge; Shaw, Michael W.; Knogge, Wolfgang; Kelly, Steven L.; Kelly, Diane E.; Fraaije, Bart A.

    2014-01-01

    Evolution of resistance to drugs and pesticides poses a serious threat to human health and agricultural production. CYP51 encodes the target site of azole fungicides, widely used clinically and in agriculture. Azole resistance can evolve due to point mutations or overexpression of CYP51, and previous studies have shown that fungicide-resistant alleles have arisen by de novo mutation. Paralogs CYP51A and CYP51B are found in filamentous ascomycetes, but CYP51A has been lost from multiple lineages. Here, we show that in the barley pathogen Rhynchosporium commune, re-emergence of CYP51A constitutes a novel mechanism for the evolution of resistance to azoles. Pyrosequencing analysis of historical barley leaf samples from a unique long-term experiment from 1892 to 2008 indicates that the majority of the R. commune population lacked CYP51A until 1985, after which the frequency of CYP51A rapidly increased. Functional analysis demonstrates that CYP51A retains the same substrate as CYP51B, but with different transcriptional regulation. Phylogenetic analyses show that the origin of CYP51A far predates azole use, and newly sequenced Rhynchosporium genomes show CYP51A persisting in the R. commune lineage rather than being regained by horizontal gene transfer; therefore, CYP51A re-emergence provides an example of adaptation to novel compounds by selection from standing genetic variation. PMID:24732957

  12. Novel Substrate Specificity and Temperature-Sensitive Activity of Mycosphaerella graminicola CYP51 Supported by the Native NADPH Cytochrome P450 Reductase

    PubMed Central

    Price, Claire L.; Warrilow, Andrew G. S.; Parker, Josie E.; Mullins, Jonathan G. L.; Nes, W. David

    2015-01-01

    Mycosphaerella graminicola (Zymoseptoria tritici) is an ascomycete filamentous fungus that causes Septoria leaf blotch in wheat crops. In Europe the most widely used fungicides for this major disease are demethylation inhibitors (DMIs). Their target is the essential sterol 14?-demethylase (CYP51), which requires cytochrome P450 reductase (CPR) as its redox partner for functional activity. The M. graminicola CPR (MgCPR) is able to catalyze the sterol 14?-demethylation of eburicol and lanosterol when partnered with Candida albicans CYP51 (CaCYP51) and that of eburicol only with M. graminicola CYP51 (MgCYP51). The availability of the functional in vivo redox partner enabled the in vitro catalytic activity of MgCYP51 to be demonstrated for the first time. MgCYP51 50% inhibitory concentration (IC50) studies with epoxiconazole, tebuconazole, triadimenol, and prothioconazole-desthio confirmed that MgCYP51 bound these azole inhibitors tightly. The characterization of the MgCPR/MgCYP51 redox pairing has produced a functional method to evaluate the effects of agricultural azole fungicides, has demonstrated eburicol specificity in the activity observed, and supports the conclusion that prothioconazole is a profungicide. PMID:25746994

  13. Novel Substrate Specificity and Temperature-Sensitive Activity of Mycosphaerella graminicola CYP51 Supported by the Native NADPH Cytochrome P450 Reductase.

    PubMed

    Price, Claire L; Warrilow, Andrew G S; Parker, Josie E; Mullins, Jonathan G L; Nes, W David; Kelly, Diane E; Kelly, Steven L

    2015-05-15

    Mycosphaerella graminicola (Zymoseptoria tritici) is an ascomycete filamentous fungus that causes Septoria leaf blotch in wheat crops. In Europe the most widely used fungicides for this major disease are demethylation inhibitors (DMIs). Their target is the essential sterol 14?-demethylase (CYP51), which requires cytochrome P450 reductase (CPR) as its redox partner for functional activity. The M. graminicola CPR (MgCPR) is able to catalyze the sterol 14?-demethylation of eburicol and lanosterol when partnered with Candida albicans CYP51 (CaCYP51) and that of eburicol only with M. graminicola CYP51 (MgCYP51). The availability of the functional in vivo redox partner enabled the in vitro catalytic activity of MgCYP51 to be demonstrated for the first time. MgCYP51 50% inhibitory concentration (IC50) studies with epoxiconazole, tebuconazole, triadimenol, and prothioconazole-desthio confirmed that MgCYP51 bound these azole inhibitors tightly. The characterization of the MgCPR/MgCYP51 redox pairing has produced a functional method to evaluate the effects of agricultural azole fungicides, has demonstrated eburicol specificity in the activity observed, and supports the conclusion that prothioconazole is a profungicide. PMID:25746994

  14. The Sch9 Kinase Regulates Conidium Size, Stress Responses, and Pathogenesis in Fusarium graminearum

    PubMed Central

    Zhou, Xiaoying; Wang, Yulin; Xu, Jin-Rong

    2014-01-01

    Fusarium head blight caused by Fusarium graminearum is an important disease of wheat and barley worldwide. In a previous study on functional characterization of the F. graminearum kinome, one protein kinase gene important for virulence is orthologous to SCH9 that is functionally related to the cAMP-PKA and TOR pathways in the budding yeast. In this study, we further characterized the functions of FgSCH9 in F. graminearum and its ortholog in Magnaporthe oryzae. The ?Fgsch9 mutant was slightly reduced in growth rate but significantly reduced in conidiation, DON production, and virulence on wheat heads and corn silks. It had increased tolerance to elevated temperatures but became hypersensitive to oxidative, hyperosmotic, cell wall, and membrane stresses. The ?Fgsch9 deletion also had conidium morphology defects and produced smaller conidia. These results suggest that FgSCH9 is important for stress responses, DON production, conidiogenesis, and pathogenesis in F. graminearum. In the rice blast fungus Magnaporthe oryzae, the ?Mosch9 mutant also was defective in conidiogenesis and pathogenesis. Interestingly, it also produced smaller conidia and appressoria. Taken together, our data indicate that the SCH9 kinase gene may have a conserved role in regulating conidium size and plant infection in phytopathogenic ascomycetes. PMID:25144230

  15. In Planta Stage-Specific Fungal Gene Profiling Elucidates the Molecular Strategies of Fusarium graminearum Growing inside Wheat Coleoptiles[W][OA

    PubMed Central

    Zhang, Xiao-Wei; Jia, Lei-Jie; Zhang, Yan; Jiang, Gang; Li, Xuan; Zhang, Dong; Tang, Wei-Hua

    2012-01-01

    The ascomycete Fusarium graminearum is a destructive fungal pathogen of wheat (Triticum aestivum). To better understand how this pathogen proliferates within the host plant, we tracked pathogen growth inside wheat coleoptiles and then examined pathogen gene expression inside wheat coleoptiles at 16, 40, and 64 h after inoculation (HAI) using laser capture microdissection and microarray analysis. We identified 344 genes that were preferentially expressed during invasive growth in planta. Gene expression profiles for 134 putative plant cell wall–degrading enzyme genes suggest that there was limited cell wall degradation at 16 HAI and extensive degradation at 64 HAI. Expression profiles for genes encoding reactive oxygen species (ROS)–related enzymes suggest that F. graminearum primarily scavenges extracellular ROS before a later burst of extracellular ROS is produced by F. graminearum enzymes. Expression patterns of genes involved in primary metabolic pathways suggest that F. graminearum relies on the glyoxylate cycle at an early stage of plant infection. A secondary metabolite biosynthesis gene cluster was specifically induced at 64 HAI and was required for virulence. Our results indicate that F. graminearum initiates infection of coleoptiles using covert penetration strategies and switches to overt cellular destruction of tissues at an advanced stage of infection. PMID:23266949

  16. Isolating Fungal Pathogens from a Dynamic Disease Outbreak in a Native Plant Population to Establish Plant-Pathogen Bioassays for the Ecological Model Plant Nicotiana attenuata

    PubMed Central

    Schuck, Stefan; Baldwin, Ian T.

    2014-01-01

    The wild tobacco species Nicotiana attenuata has been intensively used as a model plant to study its interaction with insect herbivores and pollinators in nature, however very little is known about its native pathogen community. We describe a fungal disease outbreak in a native N. attenuata population comprising 873 plants growing in an area of about 1500 m2. The population was divided into 14 subpopulations and disease symptom development in the subpopulations was monitored for 16 days, revealing a waxing and waning of visible disease symptoms with some diseased plants recovering fully. Native fungal N. attenuata pathogens were isolated from diseased plants, characterized genetically, chemotaxonomically and morphologically, revealing several isolates of the ascomycete genera Fusarium and Alternaria, that differed in the type and strength of the disease symptoms they caused in bioassays on either detached leaves or intact soil-grown plants. These isolates and the bioassays will empower the study of N. attenuata-pathogen interactions in a realistic ecological context. PMID:25036191

  17. Functional Annotation of the Ophiostoma novo-ulmi Genome: Insights into the Phytopathogenicity of the Fungal Agent of Dutch Elm Disease

    PubMed Central

    Comeau, André M.; Dufour, Josée; Bouvet, Guillaume F.; Jacobi, Volker; Nigg, Martha; Henrissat, Bernard; Laroche, Jérôme; Levesque, Roger C.; Bernier, Louis

    2015-01-01

    The ascomycete fungus Ophiostoma novo-ulmi is responsible for the pandemic of Dutch elm disease that has been ravaging Europe and North America for 50 years. We proceeded to annotate the genome of the O. novo-ulmi strain H327 that was sequenced in 2012. The 31.784-Mb nuclear genome (50.1% GC) is organized into 8 chromosomes containing a total of 8,640 protein-coding genes that we validated with RNA sequencing analysis. Approximately 53% of these genes have their closest match to Grosmannia clavigera kw1407, followed by 36% in other close Sordariomycetes, 5% in other Pezizomycotina, and surprisingly few (5%) orphans. A relatively small portion (?3.4%) of the genome is occupied by repeat sequences; however, the mechanism of repeat-induced point mutation appears active in this genome. Approximately 76% of the proteins could be assigned functions using Gene Ontology analysis; we identified 311 carbohydrate-active enzymes, 48 cytochrome P450s, and 1,731 proteins potentially involved in pathogen–host interaction, along with 7 clusters of fungal secondary metabolites. Complementary mating-type locus sequencing, mating tests, and culturing in the presence of elm terpenes were conducted. Our analysis identified a specific genetic arsenal impacting the sexual and vegetative growth, phytopathogenicity, and signaling/plant–defense–degradation relationship between O. novo-ulmi and its elm host and insect vectors. PMID:25539722

  18. Genome sequence of Valsa canker pathogens uncovers a potential adaptation of colonization of woody bark.

    PubMed

    Yin, Zhiyuan; Liu, Huiquan; Li, Zhengpeng; Ke, Xiwang; Dou, Daolong; Gao, Xiaoning; Song, Na; Dai, Qingqing; Wu, Yuxing; Xu, Jin-Rong; Kang, Zhensheng; Huang, Lili

    2015-12-01

    Canker caused by ascomycetous Valsa species are among the most destructive diseases of woody plants worldwide. These pathogens are distinct from other pathogens because they only effectively attack tree bark in the field. To unravel the potential adaptation mechanism of bark colonization, we examined the genomes of Valsa mali and Valsa pyri that preferentially infect apple and pear, respectively. We reported the 44.7 and 35.7 Mb genomes of V. mali and V. pyri, respectively. We also identified the potential genomic determinants of wood colonization by comparing them with related cereal pathogens. Both genomes encode a plethora of pathogenicity-related genes involved in plant cell wall degradation and secondary metabolite biosynthesis. In order to adapt to the nutrient limitation and low pH environment in bark, they seem to employ membrane transporters associated with nitrogen uptake and secrete proteases predominantly with acidic pH optima. Remarkably, both Valsa genomes are especially suited for pectin decomposition, but are limited in lignocellulose and cutin degradation. Besides many similarities, the two genomes show distinct variations in many secondary metabolism gene clusters. Our results show a potential adaptation of Valsa canker pathogens to colonize woody bark. Secondary metabolism gene clusters are probably responsible for this host specificity. PMID:26137988

  19. Microcyclospora and Microcyclosporella: novel genera accommodating epiphytic fungi causing sooty blotch on apple.

    PubMed

    Frank, J; Crous, P W; Groenewald, J Z; Oertel, B; Hyde, K D; Phengsintham, P; Schroers, H-J

    2010-06-01

    Recent studies have found a wide range of ascomycetes to be associated with sooty blotch and flyspeck (SBFS) blemishes on the surfaces of pomaceous fruits, specifically apples. Based on collections of such fungi from apple orchards in Germany and Slovenia we introduce two novel genera according to analyses of morphological characters and nuclear ribosomal DNA sequences (large subunit and internal transcribed spacer regions). Microcyclosporella is represented by a single species, M. mali, and is presently known from Germany and Slovenia. Microcyclosporella is Pseudocercosporella-like in morphology, but genetically and morphologically distinct from Pseudocercosporella s.str., for which an epitype is designated based on a fresh collection of P. bakeri from Laos. Furthermore, Pseudocercosporella is shown to be paraphyletic within the Capnodiales. Microcyclospora gen. nov. is Pseudocercospora-like in morphology, but is genetically and morphologically distinct from Pseudocercospora s.str., which is based on P. vitis. Three species, Microcyclospora malicola, M. pomicola (both collected in Germany), and M. tardicrescens (collected in Slovenia) are described. Finally, a new species of Devriesia, D. pseudoamericana, is described from pome fruit surfaces collected in Germany. Devriesia is shown to be paraphyletic, and to represent several lineages of which only Devriesia s.str. is thermotolerant. Further collections are required, however, before the latter generic complex can be resolved. PMID:20664763

  20. Evolution of Chemical Diversity in a Group of Non-Reduced Polyketide Gene Clusters: Using Phylogenetics to Inform the Search for Novel Fungal Natural Products.

    PubMed

    Throckmorton, Kurt; Wiemann, Philipp; Keller, Nancy P

    2015-09-01

    Fungal polyketides are a diverse class of natural products, or secondary metabolites (SMs), with a wide range of bioactivities often associated with toxicity. Here, we focus on a group of non-reducing polyketide synthases (NR-PKSs) in the fungal phylum Ascomycota that lack a thioesterase domain for product release, group V. Although widespread in ascomycete taxa, this group of NR-PKSs is notably absent in the mycotoxigenic genus Fusarium and, surprisingly, found in genera not known for their secondary metabolite production (e.g., the mycorrhizal genus Oidiodendron, the powdery mildew genus Blumeria, and the causative agent of white-nose syndrome in bats, Pseudogymnoascus destructans). This group of NR-PKSs, in association with the other enzymes encoded by their gene clusters, produces a variety of different chemical classes including naphthacenediones, anthraquinones, benzophenones, grisandienes, and diphenyl ethers. We discuss the modification of and transitions between these chemical classes, the requisite enzymes, and the evolution of the SM gene clusters that encode them. Integrating this information, we predict the likely products of related but uncharacterized SM clusters, and we speculate upon the utility of these classes of SMs as virulence factors or chemical defenses to various plant, animal, and insect pathogens, as well as mutualistic fungi. PMID:26378577

  1. Expression profiling and functional analyses of BghPTR2, a peptide transporter from Blumeria graminis f. sp. hordei.

    PubMed

    Droce, Aida; Holm, Kirsten B; Olsson, Stefan; Frandsen, Rasmus J N; Sondergaard, Teis Esben; Sřrensen, Jens Laurids; Giese, Henriette

    2015-07-01

    The obligate ascomycete parasitic fungus Blumeria graminis f. sp. hordei (Bgh) has a unique lifestyle as it is completely dependent on living barley leaves as substrate for growth. Genes involved in inorganic nitrogen utilization are notably lacking, and the fungus relies on uptake of host-derived peptides and amino acids. The PTR2 transporter family takes up di- and tri- peptides in a proton coupled process and filamentous fungi typically have two or more di/tri peptide transporters. Here we show that Bgh appear to have one PTR2 that can restore dipeptide uptake in a Saccharomyces cerevisiae PTR2 deletion strain. The Bgh PTR2 gene is expressed in conidia and germinating conidia. During Bgh infection of barley the expression level of the BghPTR2 gene is high in the appressorial germ tube, low in the haustoria and high again during conidiation and secondary infection in the compatible and intermediate resistant interactions. BghPTR2 appears to be important for the initial establishment of fungal infection but not for uptake of di-tri-peptides at the haustorial interface. Based on the expression profile we suggest that BghPTR2 is active in internal transport of nutrient reserves and/or uptake of break down products from the plant surface during the early infection stages. PMID:26058531

  2. Identification of Internal Transcribed Spacer Sequence Motifs in Truffles: a First Step toward Their DNA Bar Coding? †

    PubMed Central

    El Karkouri, Khalid; Murat, Claude; Zampieri, Elisa; Bonfante, Paola

    2007-01-01

    This work presents DNA sequence motifs from the internal transcribed spacer (ITS) of the nuclear rRNA repeat unit which are useful for the identification of five European and Asiatic truffles (Tuber magnatum, T. melanosporum, T. indicum, T. aestivum, and T. mesentericum). Truffles are edible mycorrhizal ascomycetes that show similar morphological characteristics but that have distinct organoleptic and economic values. A total of 36 out of 46 ITS1 or ITS2 sequence motifs have allowed an accurate in silico distinction of the five truffles to be made (i.e., by pattern matching and/or BLAST analysis on downloaded GenBank sequences and directly against GenBank databases). The motifs considered the intraspecific genetic variability of each species, including rare haplotypes, and assigned their respective species from either the ascocarps or ectomycorrhizas. The data indicate that short ITS1 or ITS2 motifs (?50 bp in size) can be considered promising tools for truffle species identification. A dot blot hybridization analysis of T. magnatum and T. melanosporum compared with other close relatives or distant lineages allowed at least one highly specific motif to be identified for each species. These results were confirmed in a blind test which included new field isolates. The current work has provided a reliable new tool for a truffle oligonucleotide bar code and identification in ecological and evolutionary studies. PMID:17601808

  3. Isolation of laccase gene-specific sequences from white rot and brown rot fungi by PCR

    SciTech Connect

    D`Souza, T.M.; Boominathan, K.; Reddy, C.A.

    1996-10-01

    Degenerate primers corresponding to the consensus sequences of the copper-binding regions in the N-terminal domains of known basidiomycete laccases were used to isolate laccase gene-specific sequences from strains representing nine genera of wood rot fungi. All except three gave the expected PCR product of about 200 bp. Computer searches of the databases identified the sequences of each of the PCR product of about 200 bp. Computer searches of the databases identified the sequence of each of the PCR products analyzed as a laccase gene sequence, suggesting the specificity of the primers. PCR products of the white rot fungi Ganoderma lucidum, Phlebia brevispora, and Trametes versicolor showed 65 to 74% nucleotide sequence similarity to each other; the similarity in deduced amino acid sequences was 83 to 91%. The PCR products of Lentinula edodes and Lentinus tigrinus, on the other hand, showed relatively low nucleotide and amino acid similarities (58 to 64 and 62 to 81%, respectively); however, these similarities were still much higher than when compared with the corresponding regions in the laccases of the ascomycete fungi Aspergillus nidulans and Neurospora crassa. A few of the white rot fungi, as well as Gloeophyllum trabeum, a brown rot fungus, gave a 144-bp PCR fragment which had a nucleotide sequence similarity of 60 to 71%. Demonstration of laccase activity in G. trabeum and several other brown rot fungi was of particular interest because these organisms were not previously shown to produce laccases. 36 refs., 6 figs., 2 tabs.

  4. Characterization of the Lentinula edodes exg2 gene encoding a lentinan-degrading exo-beta-1,3-glucanase.

    PubMed

    Sakamoto, Yuichi; Minato, Ken-ichiro; Nagai, Masaru; Mizuno, Masashi; Sato, Toshitsugu

    2005-09-01

    Lentinan, an antitumor substance purified from Lentinula edodes, is degraded during post-harvest preservation as a result of increased glucanase activity. We isolated an exo-beta-1,3-glucanase encoding gene, exg2, from L. edodes which is a homologue of an exo-glucanase-encoding gene conserved in ascomycetous fungi. The exg2 gene was cloned as an approximately 2.4-kbp cDNA, and as a genomic sequence of 3.9-kbp. The product of the exg2 gene is predicted to contain 759 amino acids with a molecular weight of 79 kDa and a pI value of 4.6. The putative N-terminus of EXG2 is identical to the N-terminal sequences of lentinan-degrading enzymes, GNase I and II, and a custom-made anti-EXG2 peptide anti-serum cross-reacted with purified GNase I and II. Transcription and translation of exg2 was low in the gills of mature fruiting bodies, but increased after harvesting. We conclude that the exg2 gene is a lentinan-degrading enzyme-encoding-gene in L. edodes. PMID:16133343

  5. Genomic and Proteomic Dissection of the Ubiquitous Plant Pathogen, Armillaria mellea: Toward a New Infection Model System

    PubMed Central

    2013-01-01

    Armillaria mellea is a major plant pathogen. Yet, no large-scale “-omics” data are available to enable new studies, and limited experimental models are available to investigate basidiomycete pathogenicity. Here we reveal that the A. mellea genome comprises 58.35 Mb, contains 14473 gene models, of average length 1575 bp (4.72 introns/gene). Tandem mass spectrometry identified 921 mycelial (n = 629 unique) and secreted (n = 183 unique) proteins. Almost 100 mycelial proteins were either species-specific or previously unidentified at the protein level. A number of proteins (n = 111) was detected in both mycelia and culture supernatant extracts. Signal sequence occurrence was 4-fold greater for secreted (50.2%) compared to mycelial (12%) proteins. Analyses revealed a rich reservoir of carbohydrate degrading enzymes, laccases, and lignin peroxidases in the A. mellea proteome, reminiscent of both basidiomycete and ascomycete glycodegradative arsenals. We discovered that A. mellea exhibits a specific killing effect against Candida albicans during coculture. Proteomic investigation of this interaction revealed the unique expression of defensive and potentially offensive A. mellea proteins (n = 30). Overall, our data reveal new insights into the origin of basidiomycete virulence and we present a new model system for further studies aimed at deciphering fungal pathogenic mechanisms. PMID:23656496

  6. Characterization of pectinase activity for enology from yeasts occurring in Argentine Bonarda grape

    PubMed Central

    Merín, María Gabriela; Martín, María Carolina; Rantsiou, Kalliopi; Cocolin, Luca; de Ambrosini, Vilma Inés Morata

    2015-01-01

    Pectinolytic enzymes are greatly important in winemaking due to their ability to degrade pectic polymers from grape, contributing to enhance process efficiency and wine quality. This study aimed to analyze the occurrence of pectinolytic yeasts during spontaneous fermentation of Argentine Bonarda grape, to select yeasts that produce extracellular pectinases and to characterize their pectinolytic activity under wine-like conditions. Isolated yeasts were grouped using PCR-DGGE and identified by partial sequencing of 26S rRNA gene. Isolates comprised 7 genera, with Aureobasidium pullulans as the most predominant pectinolytic species, followed by Rhodotorula dairenensis and Cryptococcus saitoi. No pectinolytic activity was detected among ascomycetous yeasts isolated on grapes and during fermentation, suggesting a low occurrence of pectinolytic yeast species in wine fermentation ecosystem. This is the first study reporting R. dairenensis and Cr. saitoi species with pectinolytic activity. R. dairenensis GM-15 produced pectinases that proved to be highly active at grape pH, at 12 °C, and under ethanol and SO2 concentrations usually found in vinifications (pectinase activity around 1.1 U/mL). This strain also produced cellulase activity at 12 °C and pH 3.5, but did not produce ?-glucosidase activity under these conditions. The strain showed encouraging enological properties for its potential use in low-temperature winemaking. PMID:26413065

  7. Identification of rice blast resistance genes in the elite hybrid rice restorer line Yahui2115.

    PubMed

    Shi, Jun; Li, Deqiang; Li, Yan; Li, Xiaoyan; Guo, Xiaoyi; Luo, Yiwan; Lu, Yuangen; Zhang, Qin; Xu, Yongju; Fan, Jing; Huang, Fu; Wang, Wenming

    2015-03-01

    Rice blast, caused by the ascomycete fungus Magnaporthe oryzae, is one of the most serious rice diseases worldwide. We previously developed an elite hybrid rice restorer line with high resistance to rice blast, Yahui2115 (YH2115). To identify the blast resistance genes in YH2115, we first performed expression profiling on previously reported blast resistance genes and disease assay on monogenic lines, and we found that Pi2, Pi9, and Pikm were the most likely resistance candidates in YH2115. Furthermore, RNA interference and linkage analysis demonstrated that silencing of Pi2 reduced the blast resistance of YH2115 and a Pi2 linkage marker was closely associated with blast resistance in an F2 population generated from YH2115. These data suggest that the broad-spectrum blast resistance gene Pi2 contributes greatly to the blast resistance of YH2115. Thus, YH2115 could be used as a new germplasm to facilitate rice blast resistance breeding in hybrid rice breeding programs. PMID:26158382

  8. Diversity and Enzymatic Profiling of Halotolerant Micromycetes from Sebkha El Melah, a Saharan Salt Flat in Southern Tunisia

    PubMed Central

    Jaouani, Atef; Neifar, Mohamed; Prigione, Valeria; Ayari, Amani; Sbissi, Imed; Ben Amor, Sonia; Ben Tekaya, Seifeddine; Varese, Giovanna Cristina; Cherif, Ameur; Gtari, Maher

    2014-01-01

    Twenty-one moderately halotolerant fungi have been isolated from sample ashes collected from Sebkha El Melah, a Saharan salt flat located in southern Tunisia. Based on morphology and sequence inference from the internal transcribed spacer regions, 28S rRNA gene and other specific genes such as ?-tubulin, actin, calmodulin, and glyceraldehyde-3-phosphate dehydrogenase, the isolates were found to be distributed over 15 taxa belonging to 6 genera of Ascomycetes: Cladosporium (n = 3), Alternaria (n = 4), Aspergillus (n = 3), Penicillium (n = 5), Ulocladium (n = 2), and Engyodontium (n = 2). Their tolerance to different concentrations of salt in solid and liquid media was examined. Excepting Cladosporium cladosporioides JA18, all isolates were considered as alkali-halotolerant since they were able to grow in media containing 10% of salt with an initial pH 10. All isolates were resistant to oxidative stresses and low temperature whereas 5 strains belonging to Alternaria, Ulocladium, and Aspergillus genera were able to grow at 45°C. The screening of fungal strains for sets of enzyme production, namely, cellulase (CMCase), amylase, protease, lipase, and laccase, in presence of 10%?NaCl, showed a variety of extracellular hydrolytic and oxidative profiles. Protease was the most abundant enzyme produced whereas laccase producers were members of the genus Cladosporium. PMID:25136587

  9. Penicillium commune metabolic profile as a promising source of antipathogenic natural products.

    PubMed

    Diblasi, Lorena; Arrighi, Federico; Silva, Julio; Bardón, Alicia; Cartagena, Elena

    2015-12-01

    Penicillium is an important genus of ascomycetous fungi in the environment and in food and drug production. This paper aims to investigate statins and antipathogenic natural products from a Penicillium commune environmental isolate. Fractions (F1, F2, F3 and F4) were obtained from an ethyl acetate extract. Direct insertion probe/electron ionisation/ion trap detection mass spectrometry (MS and MS/MS) identified lovastatin (1) in F1, while GC-MS showed that 3-isobutylhexahydropyrrolo[1,2-a]pyrazine-1,4-dione (2) was the main constituent of F2 (49.34%). F4 presented 3 (16.38%) as an analogue of 2 and their known structures were similar to that of an autoinducer-signal. F1 produced a significant decrease in the Pseudomonas aeruginosa biofilms, which is the main cause of bacterial pathogenicity. F2 and F4 were effective against Staphylococcus aureus biofilms, but when F2 was associated with oxacillin, it showed an important activity against both bacteria. These novel results suggest that P. commune INTA1 is a new source of promising antipathogenic products. PMID:25674939

  10. Anacardic acid induces apoptosis-like cell death in the rice blast fungus Magnaporthe oryzae.

    PubMed

    Muzaffar, Suhail; Bose, Chinchu; Banerji, Ashok; Nair, Bipin G; Chattoo, Bharat B

    2016-01-01

    Anacardic acid (6-pentadecylsalicylic acid), extracted from cashew nut shell liquid, is a natural phenolic lipid well known for its strong antibacterial, antioxidant, and anticancer activities. Its effect has been well studied in bacterial and mammalian systems but remains largely unexplored in fungi. The present study identifies antifungal, cytotoxic, and antioxidant activities of anacardic acid in the rice blast fungus Magnaporthe oryzae. It was found that anacardic acid causes inhibition of conidial germination and mycelial growth in this ascomycetous fungus. Phosphatidylserine externalization, chromatin condensation, DNA degradation, and loss of mitochondrial membrane potential suggest that growth inhibition of fungus is mainly caused by apoptosis-like cell death. Broad-spectrum caspase inhibitor Z-VAD-FMK treatment indicated that anacardic acid induces caspase-independent apoptosis in M. oryzae. Expression of a predicted ortholog of apoptosis-inducing factor (AIF) was upregulated during the process of apoptosis, suggesting the possibility of mitochondria dependent apoptosis via activation of apoptosis-inducing factor. Anacardic acid treatment leads to decrease in reactive oxygen species rather than increase in reactive oxygen species (ROS) accumulation normally observed during apoptosis, confirming the antioxidant properties of anacardic acid as suggested by earlier reports. Our study also shows that anacardic acid renders the fungus highly sensitive to DNA damaging agents like ethyl methanesulfonate (EMS). Treatment of rice leaves with anacardic acid prevents M. oryzae from infecting the plant without affecting the leaf, suggesting that anacardic acid can be an effective antifungal agent. PMID:26381667

  11. Endogenous ergothioneine is required for wild type levels of conidiogenesis and conidial survival but does not protect against 254 nm UV-induced mutagenesis or kill.

    PubMed

    Bello, Marco H; Mogannam, John C; Morin, Dexter; Epstein, Lynn

    2014-12-01

    Ergothioneine, a histidine derivative, is concentrated in conidia of ascomycetous fungi. To investigate the function of ergothioneine, we crossed the wild type Neurospora crassa (Egt(+)) and an ergothioneine non-producer (Egt(-), ?egt-1, a knockout in NCU04343.5) and used the Egt(+) and Egt(-) progeny strains for phenotypic analyses. Compared to the Egt(+) strains, Egt(-) strains had a 59% reduction in the number of conidia produced on Vogel's agar. After storage of Egt(+) and Egt(-) conidia at 97% and 52% relative humidity (RH) for a time course to either 17 or 98 days, respectively, Egt(-) strains had a 23% and a 18% reduction in life expectancy at 97% and 52% RH, respectively, compared to the Egt(+) strains. Based on a Cu(II) reduction assay with the chelator bathocuproinedisulfonic acid disodium salt, ergothioneine accounts for 38% and 33% of water-soluble antioxidant capacity in N. crassa conidia from seven and 20 day-old cultures, respectively. In contrast, ergothioneine did not account for significant (?=0.05) anti-oxidant capacity in mycelia, which have lower concentrations of ergothioneine than conidia. The data are consistent with the hypothesis that ergothioneine has an antioxidant function in vivo. In contrast, experiments on the spontaneous mutation rate in Egt(+) and Egt(-) strains and on the effects of 254 nm UV light on mutation rate and conidial viability do not support the hypothesis that ergothioneine protects DNA in vivo. PMID:25446508

  12. In vitro activity of colistin as single agent and in combination with antifungals against filamentous fungi occurring in patients with cystic fibrosis.

    PubMed

    Schemuth, H; Dittmer, S; Lackner, M; Sedlacek, L; Hamprecht, A; Steinmann, E; Buer, J; Rath, P-M; Steinmann, J

    2013-05-01

    Because published reports indicate that the antibiotic colistin (COL) has antifungal properties, this study investigated the antifungal in vitro activity of COL as single agent and in combination with the antifungal compounds voriconazole (VRC), caspofungin (CAS) and amphotericin B (AMB) against Scedosporium/Pseudallescheria spp., Exophiala dermatitidis and Geosmithia argillacea. In total, susceptibility was determined for 77 Scedosporium/Pseudallescheria spp., 82 E. dermatitidis and 17 G. argillacea isolates. The minimal inhibitory concentrations (MICs) of COL and the antifungals as single compound and in combination were determined with MIC test strips. Drug interactions were detected by crossing the MIC test strips at a 90ş angle. The fractional inhibitory concentration index was used to categorise the drugs' interaction. The MIC50 value of COL was 12??g?ml(-1) for S. prolificans, 16??g?ml(-1) for P. apiosperma, 16??g?ml(-1) for P. boydii, 12??g?ml(-1) for E. dermatiditis and 6??g?ml(-1) for G. argillacea. VRC was the most active drug in combination without any antagonism with the exception of few P. boydii isolates. COL as single agent and in most combinations with antifungals exhibits in vitro antifungal activity against filamentous ascomycetes occurring in cystic fibrosis patients and may offer a novel therapeutic option, especially for multidrug-resistant S. prolificans. PMID:23170818

  13. Characterization of oleaginous yeasts accumulating high levels of lipid when cultivated in glycerol and their potential for lipid production from biodiesel-derived crude glycerol.

    PubMed

    Polburee, Pirapan; Yongmanitchai, Wichien; Lertwattanasakul, Noppon; Ohashi, Takao; Fujiyama, Kazuhito; Limtong, Savitree

    2015-12-01

    This study attempted to identify oleaginous yeasts and selected the strain that accumulated the largest quantity of lipid for lipid production from glycerol. Two-step screening of 387 yeast strains revealed 23 oleaginous strains that accumulated quantities of lipid higher than 20 % of their biomass when cultivated in glycerol. These strains were identified to be four ascomycetous yeast species i.e. Candida silvae, Kodamaea ohmeri, Meyerozyma caribbica, and Pichia manshurica, and five basidiomycetous yeast species i.e. Cryptococcus cf. podzolicus, Cryptococcus laurentii, Rhodosporidium fluviale, Rhodotorula taiwanensis, and Sporidiobolus ruineniae. Rhodosporidium fluviale DMKU-RK253 accumulated the highest quantity of lipid equal to 65.2 % of its biomass (3.9 g L(-1) lipid and 6.0 g L(-1) biomass) by shaking flask cultivation in crude glycerol. The main fatty acids in the accumulated lipid of this strain consisted of oleic acid, linoleic acid, and palmitic acid. Therefore, R. fluviale DMKU-RK253 has potential for producing lipid for biodiesel manufacturing using crude glycerol as a feedstock. PMID:26615742

  14. Hagleromyces gen. nov., a yeast genus in the Saccharomycetaceae, and description of Hagleromyces aurorensis sp. nov., isolated from water tanks of bromeliads.

    PubMed

    Sousa, Francisca M P; Morais, Paula B; Lachance, Marc-André; Rosa, Carlos A

    2014-08-01

    Three strains of a novel yeast species were isolated from water tanks (phytotelmata) of a bromeliad species collected in the state of Tocantins, Brazil. Analysis of sequences for the region spanning the SSU rRNA gene, the internal transcribed spacer, the 5.8S rRNA gene and the D1/D2 domains of the LSU rRNA gene and RNA polymerase II gene showed that these novel yeasts belong to a species that is distinct from all recognized ascomycetous yeast species. Based on the results of gene sequence analyses, a novel species representing a new genus in the Saccharomycetaceae is proposed. The novel species is assigned to the genus Hagleromyces gen. nov. The three isolates of the novel yeast species failed to form sexual spores alone or in mixtures. The name Hagleromyces aurorensis sp. nov. is proposed to accommodate these isolates. The type strain of H. aurorensis sp. nov. is UFMG-CM-Y311(T) (?=?CBS 13264(T)). PMID:24879649

  15. Endophytic hyphal compartmentalization is required for successful symbiotic Ascomycota association with root cells.

    PubMed

    Abdellatif, Lobna; Bouzid, Sadok; Kaminskyj, Susan; Vujanovic, Vladimir

    2009-01-01

    Root endophytic fungi are seen as promising alternatives to replace chemical fertilizers and pesticides in sustainable and organic agriculture systems. Fungal endophytes structure formations play key roles in symbiotic intracellular association with plant-roots. To compare the morphologies of Ascomycete endophytic fungi in wheat, we analyzed growth morphologies during endophytic development of hyphae within the cortex of living vs. dead root cells. Confocal laser scanning microscopy (CLSM) was used to characterize fungal cell morphology within lactofuchsin-stained roots. Cell form regularity Ireg and cell growth direction Idir, indexes were used to quantify changes in fungal morphology. Endophyte fungi in living roots had a variable Ireg and Idir values, low colonization abundance and patchy colonization patterns, whereas the same endophyte species in dead (gamma-irradiated) roots had consistent form of cells and mostly grew parallel to the root axis. Knot, coil and vesicle structures dominated in living roots, as putative symbiotic functional organs. Finally, an increased hypha septation in living roots might indicate local specialization within endophytic Ascomycota. Our results suggested that the applied method could be expanded to other septate fungal symbionts (e.g. Basidiomycota). The latter is discussed in light of our results and other recent discoveries. PMID:19269322

  16. Glycerophospholipid Profiles of Bats with White-Nose Syndrome.

    PubMed

    Pannkuk, Evan L; McGuire, Liam P; Warnecke, Lisa; Turner, James M; Willis, Craig K R; Risch, Thomas S

    2015-01-01

    Pseudogymnoascus destructans is an ascomycetous fungus responsible for the disease dubbed white-nose syndrome (WNS) and massive mortalities of cave-dwelling bats. The fungus infects bat epidermal tissue, causing damage to integumentary cells and pilosebaceous units. Differences in epidermal lipid composition caused by P. destructans infection could have drastic consequences for a variety of physiological functions, including innate immune efficiency and water retention. While bat surface lipid and stratum corneum lipid composition have been described, the differences in epidermal lipid content between healthy tissue and P. destructans-infected tissue have not been documented. In this study, we analyzed the effect of wing damage from P. destructans infection on the epidermal polar lipid composition (glycerophospholipids [GPs] and sphingomyelin) of little brown bats (Myotis lucifugus). We hypothesized that infection would lead to lower levels of total lipid or higher oxidized lipid product proportions. Polar lipids from three damaged and three healthy wing samples were profiled by electrospray ionization tandem mass spectrometry. We found lower total broad lipid levels in damaged tissue, specifically ether-linked phospholipids, lysophospholipids, phosphatidylcholine, and phosphatidylethanolamine. Thirteen individual GP species from four broad GP classes were present in higher amounts in healthy tissue. Six unsaturated GP species were absent in damaged tissue. Our results confirm that P. destructans infection leads to altered lipid profiles. Clinical signs of WNS may include lower lipid levels and lower proportions of unsaturated lipids due to cellular and glandular damage. PMID:26052639

  17. Identification of the galactosyltransferase of Cryptococcus neoformans involved in the biosynthesis of basidiomycete-type glycosylinositolphosphoceramide

    PubMed Central

    Wohlschlager, Therese; Buser, Reto; Skowyra, Michael L; Haynes, Brian C; Henrissat, Bernard; Doering, Tamara L; Künzler, Markus; Aebi, Markus

    2013-01-01

    The pathogenic fungus Cryptococcus neoformans synthesizes a complex family of glycosylinositolphosphoceramide (GIPC) structures. These glycosphingolipids (GSLs) consist of mannosylinositolphosphoceramide (MIPC) extended by ?1-6-linked galactose, a unique structure that has to date only been identified in basidiomycetes. Further extension by up to five mannose residues and a branching xylose has been described. In this study, we identified and determined the gene structure of the enzyme Ggt1, which catalyzes the transfer of a galactose residue to MIPC. Deletion of the gene in C. neoformans resulted in complete loss of GIPCs containing galactose, a phenotype that could be restored by the episomal expression of Ggt1 in the deletion mutant. The entire annotated open reading frame, encoding a C-terminal GT31 galactosyltransferase domain and a large N-terminal domain of unknown function, was required for complementation. Notably, this gene does not encode a predicted signal sequence or transmembrane domain. The demonstration that Ggt1 is responsible for the transfer of a galactose residue to a GSL thus raises questions regarding the topology of this biosynthetic pathway and the function of the N-terminal domain. Phylogenetic analysis of the GGT1 gene shows conservation in hetero- and homobasidiomycetes but no homologs in ascomycetes or outside of the fungal kingdom. PMID:23926231

  18. Diversity of Marine-Derived Fungal Cultures Exposed by DNA Barcodes: The Algorithm Matters

    PubMed Central

    Andreakis, Nikos; Hřj, Lone; Kearns, Philip; Hall, Michael R.; Ericson, Gavin; Cobb, Rose E.; Gordon, Benjamin R.; Evans-Illidge, Elizabeth

    2015-01-01

    Marine fungi are an understudied group of eukaryotic microorganisms characterized by unresolved genealogies and unstable classification. Whereas DNA barcoding via the nuclear ribosomal internal transcribed spacer (ITS) provides a robust and rapid tool for fungal species delineation, accurate classification of fungi is often arduous given the large number of partial or unknown barcodes and misidentified isolates deposited in public databases. This situation is perpetuated by a paucity of cultivable fungal strains available for phylogenetic research linked to these data sets. We analyze ITS barcodes produced from a subsample (290) of 1781 cultured isolates of marine-derived fungi in the Bioresources Library located at the Australian Institute of Marine Science (AIMS). Our analysis revealed high levels of under-explored fungal diversity. The majority of isolates were ascomycetes including representatives of the subclasses Eurotiomycetidae, Hypocreomycetidae, Sordariomycetidae, Pleosporomycetidae, Dothideomycetidae, Xylariomycetidae and Saccharomycetidae. The phylum Basidiomycota was represented by isolates affiliated with the genera Tritirachium and Tilletiopsis. BLAST searches revealed 26 unknown OTUs and 50 isolates corresponding to previously uncultured, unidentified fungal clones. This study makes a significant addition to the availability of barcoded, culturable marine-derived fungi for detailed future genomic and physiological studies. We also demonstrate the influence of commonly used alignment algorithms and genetic distance measures on the accuracy and comparability of estimating Operational Taxonomic Units (OTUs) by the automatic barcode gap finder (ABGD) method. Large scale biodiversity screening programs that combine datasets using algorithmic OTU delineation pipelines need to ensure compatible algorithms have been used because the algorithm matters. PMID:26308620

  19. Soil yeast communities under the aggressive invasion of Sosnowsky's hogweed ( Heracleum sosnowskyi)

    NASA Astrophysics Data System (ADS)

    Glushakova, A. M.; Kachalkin, A. V.; Chernov, I. Yu.

    2015-02-01

    The year-round dynamics of the number and taxonomic composition of yeast communities in the soddy-podzolic soils under invasive thickets of Heracleum sosnowskyi were investigated. The yeast groups that are formed in the soil under the continuous Sosnowsky's hogweed thickets significantly differ from the indigenous yeast communities under the adjacent meadows. In the soils of both biotopes, typical eurybiotic yeast species predominate. In the soil under Heracleum sosnowskyi, the share of the ascomycetes Candida vartiovaarae and Wickerhamomyces anomalus is much lower, and the portion of yeast-like fungi with high hydrolytic activity such as Trichosporon moniliforme and Trichosporon porosum is greater. A possible explanation for this phenomenon is that Sosnowsky's hogweed, unlike most aboriginal meadow grasses, does not hibernate with green leaves that do not gradually die out with the formation of semidecomposed plant residues—the main source of nutrients for the soil-litter microbial complex. In addition, grasses of the lower layer do not develop under Sosnowsky's hogweed due to the strong shading and allelopathic impact preventing the development of typical epiphytic copiotrophic species of yeasts.

  20. A MAT1–2 wild-type strain from Penicillium chrysogenum: functional mating-type locus characterization, genome sequencing and mating with an industrial penicillin-producing strain

    PubMed Central

    Böhm, Julia; Dahlmann, Tim A; Gümü?er, Hendrik; Kück, Ulrich

    2015-01-01

    In heterothallic ascomycetes, mating is controlled by two nonallelic idiomorphs that determine the ‘sex’ of the corresponding strains. We recently discovered mating-type loci and a sexual life cycle in the penicillin-producing fungus, Penicillium chrysogenum. All industrial penicillin production strains worldwide are derived from a MAT1-1 isolate. No MAT1-2 strain has been investigated in detail until now. Here, we provide the first functional analysis of a MAT1-2 locus from a wild-type strain. Similar to MAT1-1, the MAT1-2 locus has functions beyond sexual development. Unlike MAT1-1, the MAT1-2 locus affects germination and surface properties of conidiospores and controls light-dependent asexual sporulation. Mating of the MAT1-2 wild type with a MAT1-1 high penicillin producer generated sexual spores. We determined the genomic sequences of parental and progeny strains using next-generation sequencing and found evidence for genome-wide recombination. SNP calling showed that derived industrial strains had an uneven distribution of point mutations compared with the wild type. We found evidence for meiotic recombination in all chromosomes. Our results point to a strategy combining the use of mating-type genes, genetics, and next-generation sequencing to optimize conventional strain improvement methods. PMID:25521009

  1. The plasma membrane H(+)-ATPase from the biotrophic rust fungus Uromyces fabae: molecular characterization of the gene (PMA1) and functional expression of the enzyme in yeast.

    PubMed

    Struck, C; Siebels, C; Rommel, O; Wernitz, M; Hahn, M

    1998-06-01

    To study the molecular basis of biotrophic nutrient uptake by plant parasitic rust fungi, the gene (Uf-PMA1) encoding the plasma membrane H(+)-ATPase from Uromyces fabae was isolated. Uf-PMA1 exists probably as a single gene. However, two nearly identical sequences were identified; the similarity apparently is due to two Uf-PMA1 alleles in the dikaryotic hyphae. Multiple Uf-PMA1 transcripts were observed during early rust development, and reduced amounts of a single Uf-PMA1 mRNA were observed in haustoria and rust-infected leaves. This is in contrast to elevated enzyme activity in haustoria compared to germinated spores (C. Struck, M. Hahn, and K. Mendgen. Fungal Genet. Biol. 20:30-35, 1996). Unexpectedly, the PMA1-encoded rust protein is more similar to H(+)-ATPases from plants (55% identity) than from ascomycetous fungi (36% identity). When the rust PMA1 cDNA was expressed in Saccharomyces cerevisiae, both the wild-type enzyme and a mutant derivative (delta 76) deleted for the 76 C-terminal amino acids were able to support growth of a yeast strain lacking its own H(+)-ATPases. Compared to the wild-type, the delta 76 mutant enzyme displayed increased affinity to ATP, a higher vanadate sensitivity, and a more alkaline pH optimum. These results indicate that the C-terminal region of the rust enzyme exhibits auto-regulatory properties. PMID:9612944

  2. Sequencing and heterologous expression in Saccharomyces cerevisiae of a Cryptococcus neoformans cDNA encoding a plasma membrane H(+)-ATPase.

    PubMed

    Gorgojo, B; Portillo, F; Martínez-Suárez, J V

    2000-12-20

    A cDNA containing an open reading frame encoding a putative plasma membrane H(+)-ATPase in the human pathogenic basidiomycetous yeast Cryptococcus neoformans was cloned and sequenced by means of PCR and cDNA library hybridization. The cloned cDNA is 3475 bp in length, containing a 2994 bp open reading frame encoding a polypeptide of 997 amino acids. As in the case of another basidiomycetous fungus (Uromyces fabae), the deduced amino acid sequence of CnPMA1 was found to be more homologous to those of P-type H(+)-ATPases from higher plants than to those from ascomycetous fungi. In order to prove the sequenced cDNA corresponds to a H(+)-ATPase, it was expressed in Saccharomyces cerevisiae and found to functionally replace its own H(+)-ATPase. Kinetic studies of CnPMA1 compared to ScPMA1 show differences in V(max) values and H(+)-pumping in reconstituted vesicles. The pH optimum and K(m) values are similar in both enzymes. PMID:11118522

  3. Sda1, a Cys2-His2 Zinc Finger Transcription Factor, Is Involved in Polyol Metabolism and Fumonisin B1 Production in Fusarium verticillioides

    PubMed Central

    Malapi-Wight, Martha; Smith, Jonathon; Campbell, Jacquelyn; Bluhm, Burton H.; Shim, Won-Bo

    2013-01-01

    The ubiquitous ascomycete Fusarium verticillioides causes ear rot and stalk rot of maize, both of which reduce grain quality and yield. Additionally, F. verticillioides produces the mycotoxin fumonisin B1 (FB1) during infection of maize kernels, and thus potentially compromises human and animal health. The current knowledge is fragmentary regarding the regulation of FB1 biosynthesis, particularly when considering interplay with environmental factors such as nutrient availability. In this study, SDA1 of F. verticillioides, predicted to encode a Cys-2 His-2 zinc finger transcription factor, was shown to play a key role in catabolizing select carbon sources. Growth of the SDA1 knock-out mutant (?sda1) was completely inhibited when sorbitol was the sole carbon source and was severely impaired when exclusively provided mannitol or glycerol. Deletion of SDA1 unexpectedly increased FB1 biosynthesis, but reduced arabitol and mannitol biosynthesis, as compared to the wild-type progenitor. Trichoderma reesei ACE1, a regulator of cellulase and xylanase expression, complemented the F. verticillioides ?sda1 mutant, which indicates that Ace1 and Sda1 are functional orthologs. Taken together, the data indicate that Sda1 is a transcriptional regulator of carbon metabolism and toxin production in F. verticillioides. PMID:23844049

  4. Methods to control ectomycorrhizal colonization: effectiveness of chemical and physical barriers.

    PubMed

    Teste, François P; Karst, Justine; Jones, Melanie D; Simard, Suzanne W; Durall, Daniel M

    2006-12-01

    We conducted greenhouse experiments using Douglas-fir (Pseudotsuga menziesii var. glauca) seedlings where chemical methods (fungicides) were used to prevent ectomycorrhizal colonization of single seedlings or physical methods (mesh barriers) were used to prevent formation of mycorrhizal connections between neighboring seedlings. These methods were chosen for their ease of application in the field. We applied the fungicides, Topas (nonspecific) and Senator (ascomycete specific), separately and in combination at different concentrations and application frequencies to seedlings grown in unsterilized forest soils. Additionally, we assessed the ability of hyphae to penetrate mesh barriers of various pore sizes (0.2, 1, 20, and 500 microm) to form mycorrhizas on roots of neighboring seedlings. Ectomycorrhizal colonization was reduced by approximately 55% with the application of Topas at 0.5 g l(-1). Meshes with pore sizes of 0.2 and 1 microm were effective in preventing the formation of mycorrhizas via hyphal growth across the mesh barriers. Hence, meshes in this range of pore sizes could also be used to prevent the formation of common mycorrhizal networks in the field. Depending on the ecological question of interest, Topas or the employment of mesh with pore sizes <1 microm are suitable for restricting mycorrhization in the field. PMID:17106724

  5. Rock-inhabiting fungi originated during periods of dry climate in the late Devonian and middle Triassic.

    PubMed

    Gueidan, Cécile; Ruibal, Constantino; de Hoog, G S; Schneider, Harald

    2011-10-01

    Non-lichenized rock-inhabiting fungi (RIF) are slow-growing melanized ascomycetes colonizing rock surfaces in arid environments. They possess adaptations, which allow them to tolerate extreme abiotic conditions, such as high UV radiations and extreme temperatures. They belong to two separate lineages, one consisting in the sister classes Dothideomycetes and Arthoniomycetes (Dothideomyceta), and the other consisting in the order Chaetothyriales (Eurotiomycetes). Because RIF often form early diverging groups in Chaetothyriales and Dothideomyceta, the ancestors of these two lineages were suggested to most likely be rock-inhabitants. The lineage of RIF related to the Chaetothyriales shows a much narrower phylogenetic spectrum than the lineage of RIF related to Dothideomyceta, suggesting a much more ancient origin for the latter. Our study aims at investigating the times of origin of RIF using a relaxed clock model and several fossil and secondary calibrations. Our results show that the RIF in Dothideomyceta evolved in the late Devonian, much earlier than the RIF in Chaetothyriales, which originated in the middle Triassic. The origin of the chaetothyrialean RIF correlates well with a period of recovery after the Permian-Triassic mass extinction and an expansion of arid landmasses. The period preceding the diversification of the RIF related to Dothideomyceta (Silurian--Devonian) is also characterized by large arid landmasses, but temperatures were much cooler than during the Triassic. The paleoclimate record provides a good explanation for the diversification of fungi subjected to abiotic stresses and adapted to life on rock surfaces in nutrient-poor habitats. PMID:21944211

  6. Microbial colonization affects the efficiency of photovoltaic panels in a tropical environment.

    PubMed

    Shirakawa, Marcia A; Zilles, Roberto; Mocelin, Andre; Gaylarde, Christine C; Gorbushina, Anna; Heidrich, Gabriele; Giudice, Mauro C; Del Negro, Gilda M B; John, Vanderley M

    2015-07-01

    Sub-aerial biofilm (SAB) development on solar panels was studied in Săo Paulo. After 6, 12 and 18 months' exposure, photovoltaic panels were covered by increasing proportions of organic matter (42%, 53% and 58%, respectively). Fungi were an important component of these biofilms; very few phototrophs were found. Major microorganisms detected were melanised meristematic ascomycetes and pigmented bacterial genera Arthrobacter and Tetracoccus. While diverse algae, cyanobacteria and bacteria were identified in biofilms at 6 and 12 months, diversity at a later stage was reduced to that typical for SAB: the only fungal group detected in 18 month biofilm was the meristematic Dothideomycetes and the only phototrophs Ulothrix and Chlorella. Photovoltaic modules showed significant power reductions after 6, 12 (both 7%) and 18 (11%) months. The lack of difference in power reduction between 6 and 12 months reflects the dual nature of soiling, which can result from the deposition of particulates as well as from SAB fouling. Although 12-month old SAB demonstrated an almost 10-fold increase in fungal colonization and a higher organic content, the larger non-microbial particles (above 10 ?m), which were important for efficiency reduction of lightly-biofilmed panels, were removed by high rainfall just before the 12-month sampling. PMID:25909440

  7. Characterization of pectinase activity for enology from yeasts occurring in Argentine Bonarda grape.

    PubMed

    Merín, María Gabriela; Martín, María Carolina; Rantsiou, Kalliopi; Cocolin, Luca; de Ambrosini, Vilma Inés Morata

    2015-01-01

    Pectinolytic enzymes are greatly important in winemaking due to their ability to degrade pectic polymers from grape, contributing to enhance process efficiency and wine quality. This study aimed to analyze the occurrence of pectinolytic yeasts during spontaneous fermentation of Argentine Bonarda grape, to select yeasts that produce extracellular pectinases and to characterize their pectinolytic activity under wine-like conditions. Isolated yeasts were grouped using PCR-DGGE and identified by partial sequencing of 26S rRNA gene. Isolates comprised 7 genera, with Aureobasidium pullulans as the most predominant pectinolytic species, followed by Rhodotorula dairenensis and Cryptococcus saitoi. No pectinolytic activity was detected among ascomycetous yeasts isolated on grapes and during fermentation, suggesting a low occurrence of pectinolytic yeast species in wine fermentation ecosystem. This is the first study reporting R. dairenensis and Cr. saitoi species with pectinolytic activity. R. dairenensis GM-15 produced pectinases that proved to be highly active at grape pH, at 12 °C, and under ethanol and SO2 concentrations usually found in vinifications (pectinase activity around 1.1 U/mL). This strain also produced cellulase activity at 12 °C and pH 3.5, but did not produce ?-glucosidase activity under these conditions. The strain showed encouraging enological properties for its potential use in low-temperature winemaking. PMID:26413065

  8. Mating type-dependent partner sensing as mediated by VEL1 in Trichoderma reesei.

    PubMed

    Bazafkan, Hoda; Dattenböck, Christoph; Böhmdorfer, Stefan; Tisch, Doris; Stappler, Eva; Schmoll, Monika

    2015-06-01

    Sexual development in the filamentous model ascomycete Trichoderma reesei (syn. Hypocrea jecorina) was described only a few years ago. In this study, we show a novel role for VELVET in fungi, which links light response, development and secondary metabolism. Vel1 is required for mating in darkness, normal growth and conidiation. In light, vel1 was dispensable for male fertility but essential for female fertility in both mating types. VEL1 impacted regulation of the pheromone system (hpr1, hpr2, hpp1, ppg1) in a mating type-dependent manner and depending on the mating partner of a given strain. These partner effects only occurred for hpp1 and hpr2, the pheromone precursor and receptor genes associated with the MAT1-2 mating type and for the mating type gene mat1-2-1. Analysis of secondary metabolite patterns secreted by wild type and mutants under asexual and sexual conditions revealed that even in the wild type, the patterns change upon encounter of a mating partner, with again distinct differences for wild type and vel1 mutants. Hence, T.?reesei applies a language of pheromones and secondary metabolites to communicate with mating partners and that this communication is at least in part mediated by VEL1. PMID:25757597

  9. Patterns of organic acids exuded by pioneering fungi from a glacier forefield are affected by carbohydrate sources

    NASA Astrophysics Data System (ADS)

    Brunner, Ivano; Goren, Asena; Schlumpf, Alessandro

    2014-01-01

    Bare soils in the area of retreating glaciers are ideal environments to study the role of microorganisms in the early soil formation and in processes of mineral weathering. The aim of our study was to investigate whether the source of carbohydrate would influence the patterns of organic acids exuded by fungal species. Three pioneering fungus species, isolated from fine granitic sediments in front of the Damma glacier from the central Swiss Alps, have previously been found to have the capability to exude organic acids and dissolve granite powder. In batch experiments, various carbohydrates, including glucose, cellulose, pectin, pollen, and cell remnants of cyanobacteria, fungi, and algae, were applied as carbohydrate sources and the patterns of exuded organic acids recorded. The results showed that two fungi, the zygomycete fungus Mucor hiemalis and the ascomycete fungus Penicillium chrysogenum, released a significantly higher amount of organic acids in dependence on specific carbohydrate sources. Pollen and algae as carbohydrate sources triggered significantly the exudation of malate in M. hiemalis, and pollen and cellulose that of oxalate in P. chrysogenum. We conclude that the occurrence of complex carbohydrate sources in nutrient-deficient deglaciated soils may positively influence the exudation of organic acids of fungi. In particular, pollen and remnants of other microorganisms can trigger the exudation of organic acids of fungi in order to promote the weathering of minerals and to make nutrients available that would otherwise be trapped in that cryospheric environment.

  10. Insight into the antifungal mechanism of Neosartorya fischeri antifungal protein.

    PubMed

    Virágh, Máté; Marton, Annamária; Vizler, Csaba; Tóth, Liliána; Vágvölgyi, Csaba; Marx, Florentine; Galgóczy, László

    2015-07-01

    Small, cysteine-rich, highly stable antifungal proteins secreted by filamentous Ascomycetes have great potential for the development of novel antifungal strategies. However, their practical application is still limited due to their not fully clarified mode of action. The aim of this work was to provide a deep insight into the antifungal mechanism of Neosartorya fischeri antifungal protein (NFAP), a novel representative of this protein group. Within a short exposure time to NFAP, reduced cellular metabolism, apoptosis induction, changes in the actin distribution and chitin deposition at the hyphal tip were observed in NFAP-sensitive Aspergillus nidulans. NFAP did show neither a direct membrane disrupting-effect nor uptake by endocytosis. Investigation of A. nidulans signalling mutants revealed that NFAP activates the cAMP/protein kinase A pathway via G-protein signalling which leads to apoptosis and inhibition of polar growth. In contrast, NFAP does not have any influence on the cell wall integrity pathway, but an unknown cell wall integrity pathway-independent mitogen activated protein kinase A-activated target is assumed to be involved in the cell death induction. Taken together, it was concluded that NFAP shows similarities, but also differences in its mode of antifungal action compared to two most investigated NFAP-related proteins from Aspergillus giganteus and Penicillium chrysogenum. PMID:25994413

  11. Fungal endophytic communities on twigs of fast and slow growing Scots pine (Pinus sylvestris L.) in northern Spain.

    PubMed

    Sanz-Ros, Antonio V; Müller, Michael M; San Martín, Roberto; Diez, Julio J

    2015-10-01

    Most plant species harbour a diverse community of endophytic, but their role is still unknown in most cases, including ecologically and economically important tree species. This study describes the culturable fungal endophytic community of Pinus sylvestris L. twigs in northern Spain and its relationship with diametric growth of the host. In all, 360 twig samples were collected from 30 Scots pines in fifteen stands. Isolates were obtained from all twig samples and 43 fungal taxa were identified by morphogrouping and subsequent ITS rDNA sequencing. All isolates were Ascomycetes, being Dothideomycetes and Sordariomycetes the most abundant classes. Half of the species were host generalists while the others were conifer or pine specialists. We found three new endophytic species for the Pinaceae: Biscogniauxia mediterranea, Phaeomoniella effusa and Plectania milleri, and additional six new species for P. sylvestris: Daldinia fissa, Hypocrea viridescens, Nigrospora oryzae, Ophiostoma nigrocarpum, Penicillium melinii and Penicillium polonicum. The endophytic community of fast and slow growing trees showed differences in species composition, abundance and evenness, but not in diversity. Phoma herbarum was associated to fast growing trees and Hypocrea lixii to those growing slow. Our results support the hypothesis that some endophytic species may affect growth of P. sylvestris. PMID:26399183

  12. Relationships between Swiss needle cast and ectomycorrhizal fungus diversity.

    PubMed

    Luoma, Daniel L; Eberhart, Joyce L

    2014-01-01

    Swiss needle cast (SNC) is a disease specific to Douglas-fir (Pseudotsuga menziesii) caused by the ascomycete Phaeocryptopus gaeumannii. Here we examine characteristics of the EM fungus community that are potentially useful in predictive models that would monitor forest health. We found that mean EM density (number of colonized root tips/soil core) varied nearly 10-fold among sites of varying levels of SNC, while mean EM fungus species richness (number of species/soil core) varied by about 2.5 times. Strong relationships were found between EM and SNC parameters: EM species richness was positively correlated with both Douglas-fir needle retention (R(2) = 0.93) and EM density (R(2) = 0.65); EM density also was significantly correlated with Douglas-fir needle retention (R(2) = 0.70). These simple characteristics of the EM fungus community could be used to monitor forest health and generate predictive models of site suitability for Douglas-fir. Based on previous findings that normally common EM types were reduced in frequency on sites with severe SNC, we also hypothesized that some EM fungi would be stress tolerant-dominant species. Instead, we found that various fungi were able to form EM with the stressed trees, but none were consistently dominant across samples in the severely diseased areas. PMID:24895426

  13. Convergent evolution of a fused sexual cycle promotes the haploid lifestyle

    NASA Astrophysics Data System (ADS)

    Sherwood, Racquel Kim; Scaduto, Christine M.; Torres, Sandra E.; Bennett, Richard J.

    2014-02-01

    Sexual reproduction is restricted to eukaryotic species and involves the fusion of haploid gametes to form a diploid cell that subsequently undergoes meiosis to generate recombinant haploid forms. This process has been extensively studied in the unicellular yeast Saccharomyces cerevisiae, which exhibits separate regulatory control over mating and meiosis. Here we address the mechanism of sexual reproduction in the related hemiascomycete species Candida lusitaniae. We demonstrate that, in contrast to S. cerevisiae, C. lusitaniae exhibits a highly integrated sexual program in which the programs regulating mating and meiosis have fused. Profiling of the C. lusitaniae sexual cycle revealed that gene expression patterns during mating and meiosis were overlapping, indicative of co-regulation. This was particularly evident for genes involved in pheromone MAPK signalling, which were highly induced throughout the sexual cycle of C. lusitaniae. Furthermore, genetic analysis showed that the orthologue of IME2, a `diploid-specific' factor in S. cerevisiae, and STE12, the master regulator of S. cerevisiae mating, were each required for progression through both mating and meiosis in C. lusitaniae. Together, our results establish that sexual reproduction has undergone significant rewiring between S. cerevisiae and C. lusitaniae, and that a concerted sexual cycle operates in C. lusitaniae that is more reminiscent of the distantly related ascomycete, Schizosaccharomyces pombe. We discuss these results in light of the evolution of sexual reproduction in yeast, and propose that regulatory coupling of mating and meiosis has evolved multiple times as an adaptation to promote the haploid lifestyle.

  14. A structural model of PpoA derived from SAXS-analysis-implications for substrate conversion.

    PubMed

    Koch, Christian; Tria, Giancarlo; Fielding, Alistair J; Brodhun, Florian; Valerius, Oliver; Feussner, Kirstin; Braus, Gerhard H; Svergun, Dmitri I; Bennati, Marina; Feussner, Ivo

    2013-09-01

    In plants and mammals, oxylipins may be synthesized via multi step processes that consist of dioxygenation and isomerization of the intermediately formed hydroperoxy fatty acid. These processes are typically catalyzed by two distinct enzyme classes: dioxygenases and cytochrome P450 enzymes. In ascomycetes biosynthesis of oxylipins may proceed by a similar two-step pathway. An important difference, however, is that both enzymatic activities may be combined in a single bifunctional enzyme. These types of enzymes are named Psi-factor producing oxygenases (Ppo). Here, the spatial organization of the two domains of PpoA from Aspergillus nidulans was analyzed by small-angle X-ray scattering and the obtained data show that the enzyme exhibits a relatively flat trimeric shape. Atomic structures of the single domains were obtained by template-based structure prediction and docked into the enzyme envelope of the low resolution structure obtained by SAXS. EPR-based distance measurements between the tyrosyl radicals formed in the activated dioxygenase domain of the enzyme supported the trimeric structure obtained from SAXS and the previous assignment of Tyr374 as radical-site in PpoA. Furthermore, two phenylalanine residues in the cytochrome P450 domain were shown to modulate the specificity of hydroperoxy fatty acid rearrangement. PMID:23797010

  15. Molecular Genetic Variation in Emmonsia crescens and Emmonsia parva, Etiologic Agents of Adiaspiromycosis, and Their Phylogenetic Relationship to Blastomyces dermatitidis (Ajellomyces dermatitidis) and Other Systemic Fungal Pathogens

    PubMed Central

    Peterson, Stephen W.; Sigler, Lynne

    1998-01-01

    Emmonsia crescens, an agent of adiaspiromycosis, Blastomyces dermatitidis, the agent of blastomycosis, and Histoplasma capsulatum, the agent of histoplasmosis, are known to form meiotic (sexual) stages in the ascomycete genus Ajellomyces (Onygenaceae, Onygenales), but no sexual stage is known for E. parva, the type species of the genus Emmonsia. To evaluate relationships among members of the putative Ajellomyces clade, large-subunit ribosomal and internal transcribed spacer region DNA sequences were determined from PCR-amplified DNA fragments. Sequences were analyzed phylogenetically to evaluate the genetic variation within the genus Emmonsia and evolutionary relationships to other taxa. E. crescens and E. parva are distinct species. E. crescens isolates are placed into two groups that correlate with their continents of origin. Considerable variation occurred among isolates previously classified as E. parva. Most isolates are placed into two closely related groups, but the remaining isolates, including some from human sources, are phylogenetically distinct and represent undescribed species. Strains of B. dermatitidis are a sister species of E. parva. Paracoccidioides brasiliensis and Histoplasma capsulatum are ancestral to most Emmonsia isolates, and P. brasiliensis, which has no known teleomorph, falls within the Ajellomyces clade. PMID:9738044

  16. Ecology of Subglacial Lake Vostok (Antarctica), Based on Metagenomic/Metatranscriptomic Analyses of Accretion Ice

    PubMed Central

    Rogers, Scott O.; Shtarkman, Yury M.; Koçer, Zeynep A.; Edgar, Robyn; Veerapaneni, Ram; D’Elia, Tom

    2013-01-01

    Lake Vostok is the largest of the nearly 400 subglacial Antarctic lakes and has been continuously buried by glacial ice for 15 million years. Extreme cold, heat (from possible hydrothermal activity), pressure (from the overriding glacier) and dissolved oxygen (delivered by melting meteoric ice), in addition to limited nutrients and complete darkness, combine to produce one of the most extreme environments on Earth. Metagenomic/metatranscriptomic analyses of ice that accreted over a shallow embayment and over the southern main lake basin indicate the presence of thousands of species of organisms (94% Bacteria, 6% Eukarya, and two Archaea). The predominant bacterial sequences were closest to those from species of Firmicutes, Proteobacteria and Actinobacteria, while the predominant eukaryotic sequences were most similar to those from species of ascomycetous and basidiomycetous Fungi. Based on the sequence data, the lake appears to contain a mixture of autotrophs and heterotrophs capable of performing nitrogen fixation, nitrogen cycling, carbon fixation and nutrient recycling. Sequences closest to those of psychrophiles and thermophiles indicate a cold lake with possible hydrothermal activity. Sequences most similar to those from marine and aquatic species suggest the presence of marine and freshwater regions. PMID:24832801

  17. A New Subtilase-Like Protease Deriving from Fusarium equiseti with High Potential for Industrial Applications.

    PubMed

    Juntunen, Kari; Mäkinen, Susanna; Isoniemi, Sari; Valtakari, Leena; Pelzer, Alexander; Jänis, Janne; Paloheimo, Marja

    2015-09-01

    A gene encoding a novel extracellular subtilisin-like protease was cloned from the ascomycete Fusarium equiseti and expressed in Trichoderma reesei. The F. equiseti protease (Fe protease) showed excellent performance in stain removal and good compatibility with several commercial laundry detergent formulations, suggesting that it has high potential for use in various industrial applications. The recombinant enzyme was purified and characterized. The temperature optimum of the Fe protease was 60 °C and it showed high activity in the pH range of 6-10, with a sharp decline in activity at pH above 10. The amino acid specificity of the Fe protease was studied using casein, cytochrome c, and ubiquitin as substrates. The Fe protease had broad substrate specificity: almost all amino acid residues were accepted at position P1, even though it showed some preference for cleavage at the C-terminal side of asparagine and histidine residues. The S4 subsite of Fe protease favors aspartic acid and threonine. The other well-characterized proteases from filamentous fungi, Proteinase K from Engyodontium album, Thermomycolin from Malbranchea sulfurea, and alkaline subtilisins from Bacillus species prefer hydrophobic amino acids in both the S1 and S4 subsites. Due to its different specificity compared to the members of the S8 family of clan SB of proteases, we consider that the Fe protease is a new protease. It does not belong to any previously defined IUBMB groups of proteases. PMID:26178876

  18. A versatile toolkit for high throughput functional genomics with Trichoderma reesei

    SciTech Connect

    Schuster, Andre; Bruno, Kenneth S.; Collett, James R.; Baker, Scott E.; Seiboth, Bernhard; Kubicek, Christian P.; Schmoll, Monika

    2012-01-02

    The ascomycete fungus, Trichoderma reesei (anamorph of Hypocrea jecorina), represents a biotechnological workhorse and is currently one of the most proficient cellulase producers. While strain improvement was traditionally accomplished by random mutagenesis, a detailed understanding of cellulase regulation can only be gained using recombinant technologies. RESULTS: Aiming at high efficiency and high throughput methods, we present here a construction kit for gene knock out in T. reesei. We provide a primer database for gene deletion using the pyr4, amdS and hph selection markers. For high throughput generation of gene knock outs, we constructed vectors using yeast mediated recombination and then transformed a T. reesei strain deficient in non-homologous end joining (NHEJ) by spore electroporation. This NHEJ-defect was subsequently removed by crossing of mutants with a sexually competent strain derived from the parental strain, QM9414.CONCLUSIONS:Using this strategy and the materials provided, high throughput gene deletion in T. reesei becomes feasible. Moreover, with the application of sexual development, the NHEJ-defect can be removed efficiently and without the need for additional selection markers. The same advantages apply for the construction of multiple mutants by crossing of strains with different gene deletions, which is now possible with considerably less hands-on time and minimal screening effort compared to a transformation approach. Consequently this toolkit can considerably boost research towards efficient exploitation of the resources of T. reesei for cellulase expression and hence second generation biofuel production.

  19. WD40-Repeat Proteins in Plant Cell Wall Formation: Current Evidence and Research Prospects

    PubMed Central

    Guerriero, Gea; Hausman, Jean-Francois; Ezcurra, Inés

    2015-01-01

    The metabolic complexity of living organisms relies on supramolecular protein structures which ensure vital processes, such as signal transduction, transcription, translation and cell wall synthesis. In eukaryotes WD40-repeat (WDR) proteins often function as molecular “hubs” mediating supramolecular interactions. WDR proteins may display a variety of interacting partners and participate in the assembly of complexes involved in distinct cellular functions. In plants, the formation of lignocellulosic biomass involves extensive synthesis of cell wall polysaccharides, a process that requires the assembly of large transmembrane enzyme complexes, intensive vesicle trafficking, interactions with the cytoskeleton, and coordinated gene expression. Because of their function as supramolecular hubs, WDR proteins could participate in each or any of these steps, although to date only few WDR proteins have been linked to the cell wall by experimental evidence. Nevertheless, several potential cell wall-related WDR proteins were recently identified using in silico approaches, such as analyses of co-expression, interactome and conserved gene neighborhood. Notably, some WDR genes are frequently genomic neighbors of genes coding for GT2-family polysaccharide synthases in eukaryotes, and this WDR-GT2 collinear microsynteny is detected in diverse taxa. In angiosperms, two WDR genes are collinear to cellulose synthase genes, CesAs, whereas in ascomycetous fungi several WDR genes are adjacent to chitin synthase genes, chs. In this Perspective we summarize and discuss experimental and in silico studies on the possible involvement of WDR proteins in plant cell wall formation. The prospects of biotechnological engineering for enhanced biomass production are discussed.

  20. Anti-Inflammatory Properties of the Medicinal Mushroom Cordyceps militaris Might Be Related to Its Linear (1?3)-?-D-Glucan

    PubMed Central

    Smiderle, Fhernanda R.; Baggio, Cristiane H.; Borato, Débora G.; Santana-Filho, Arquimedes P.; Sassaki, Guilherme L.; Iacomini, Marcello; Van Griensven, Leo J. L. D.

    2014-01-01

    The Ascomycete Cordyceps militaris, an entomopathogenic fungus, is one of the most important traditional Chinese medicines. Studies related to its pharmacological properties suggest that this mushroom can exert interesting biological activities. Aqueous (CW and HW) and alkaline (K5) extracts containing polysaccharides were prepared from this mushroom, and a ?-D-glucan was purified. This polymer was analysed by GC-MS and NMR spectrometry, showing a linear chain composed of ?-D-Glcp (1?3)-linked. The six main signals in the 13C-NMR spectrum were assigned by comparison to reported data. The aqueous (CW, HW) extracts stimulated the expression of IL-1?, TNF-?, and COX-2 by THP-1 macrophages, while the alkaline (K5) extract did not show any effect. However, when the extracts were added to the cells in the presence of LPS, K5 showed the highest inhibition of the pro-inflammatory genes expression. This inhibitory effect was also observed for the purified ?-(1?3)-D-glucan, that seems to be the most potent anti-inflammatory compound present in the polysaccharide extracts of C. militaris. In vivo, ?-(1?3)-D-glucan also inhibited significantly the inflammatory phase of formalin-induced nociceptive response, and, in addition, it reduced the migration of total leukocytes but not the neutrophils induced by LPS. In conclusion, this study clearly demonstrates the anti-inflammatory effect of ?-(1?3)-D-glucan. PMID:25330371

  1. Saccharification of Lignocelluloses by Carbohydrate Active Enzymes of the White Rot Fungus Dichomitus squalens

    PubMed Central

    Rytioja, Johanna; Hildén, Kristiina; Mäkinen, Susanna; Vehmaanperä, Jari; Hatakka, Annele; Mäkelä, Miia R.

    2015-01-01

    White rot fungus Dichomitus squalens is an efficient lignocellulose degrading basidiomycete and a promising source for new plant cell wall polysaccharides depolymerizing enzymes. In this work, we focused on cellobiohydrolases (CBHs) of D. squalens. The native CBHI fraction of the fungus, consisting three isoenzymes, was purified and it maintained the activity for 60 min at 50°C, and was stable in acidic pH. Due to the lack of enzyme activity assay for detecting only CBHII activity, CBHII of D. squalens was produced recombinantly in an industrially important ascomycete host, Trichoderma reesei. CBH enzymes of D. squalens showed potential in hydrolysis of complex lignocellulose substrates sugar beet pulp and wheat bran, and microcrystalline cellulose, Avicel. Recombinant CBHII (rCel6A) of D. squalens hydrolysed all the studied plant biomasses. Compared to individual activities, synergistic effect between rCel6A and native CBHI fraction of D. squalens was significant in the hydrolysis of Avicel. Furthermore, the addition of laccase to the mixture of CBHI fraction and rCel6A significantly enhanced the amount of released reducing sugars from sugar beet pulp. Especially, synergy between individual enzymes is a crucial factor in the tailor-made enzyme mixtures needed for hydrolysis of different plant biomass feedstocks. Our data supports the importance of oxidoreductases in improved enzyme cocktails for lignocellulose saccharification. PMID:26660105

  2. FvSO regulates vegetative hyphal fusion, asexual growth, fumonisin B1 production, and virulence in Fusarium verticillioides.

    PubMed

    Guo, Li; Wenner, Nancy; Kuldau, Gretchen A

    2015-12-01

    Hyphal anastomosis is a hallmark of filamentous fungi and plays vital roles including cellular homoeostasis, interhyphal communication and nutrient translocation. Here we identify a gene, FvSO, in Fusarium verticillioides, a filamentous ascomycete causing maize ear and stalk rot and producing fumonisin mycotoxins. FvSO, like its Neurospora crassa homologue SO, is required for vegetative hyphal fusion. It is also essential for normal vegetative growth, sporulation, and pathogenesis. FvSO encodes a predicted WW domain protein and shares 70 % protein sequence identity with N. crassa SO. FvSO deletion mutants (?FvSO) had abnormal distribution of conidia size, and conidia of ?FvSO germinated much later and slower than wild type. ?FvSO was deficient in hyphal anastomosis, had slower radial growth and produced less fungal biomass than wild type. ?FvSO were unable to perform anastomosis, a key feature of filamentous fungi. Interestingly, production of fumonisin B1 by ?FvSO was significantly reduced compared to wild type. Additionally, ?FvSO was nonpathogenic to corn ears, stalks and seedlings, likely due to defective growth and development. In conclusion, FvSO is essential for vegetative hyphal fusion and is required for normal vegetative growth and sporulation, normal levels of fumonisin production and pathogenicity in F. verticillioides. The pleiotropic nature of ?FvSO phenotypes suggests that FvSO is likely involved in certain signalling pathways that regulate multiple cellular functions. PMID:26615739

  3. Forestry impacts on the hidden fungal biodiversity associated with bryophytes.

    PubMed

    Davey, Marie L; Kauserud, Hĺvard; Ohlson, Mikael

    2014-10-01

    Recent studies have revealed an unexpectedly high, cryptic diversity of fungi associated with boreal forest bryophytes. Forestry practices heavily influence the boreal forest and fundamentally transform the landscape. However, little is known about how bryophyte-associated fungal communities are affected by these large-scale habitat transformations. This study assesses to what degree bryophyte-associated fungal communities are structured across the forest successional stages created by current forestry practices. Shoots of Hylocomium splendens were collected in Picea abies dominated forests of different ages, and their associated fungal communities were surveyed by pyrosequencing of ITS2 amplicons. Although community richness, diversity and evenness were relatively stable across the forest types and all were consistently dominated by ascomycete taxa, there was a marked shift in fungal community composition between young and old forests. Numerous fungal operational taxonomic units (OTUs) showed distinct affinities for different forest ages. Spatial structure was also detected among the sites, suggesting that environmental gradients resulting from the topography of the study area and dispersal limitations may also significantly affect bryophyte-associated fungal community structure. This study confirms that Hylocomium splendens hosts an immense diversity of fungi and demonstrates that this community is structured in part by forest age, and as such is highly influenced by modern forestry practices. PMID:25056806

  4. Diversity of the cassiicolin gene in Corynespora cassiicola and relation with the pathogenicity in Hevea brasiliensis.

    PubMed

    Déon, Marine; Fumanal, Boris; Gimenez, Stéphanie; Bieysse, Daniel; Oliveira, Ricardo R; Shuib, Siti Shuhada; Breton, Frédéric; Elumalai, Sunderasan; Vida, Joăo B; Seguin, Marc; Leroy, Thierry; Roeckel-Drevet, Patricia; Pujade-Renaud, Valérie

    2014-01-01

    Corynespora cassiicola is an important plant pathogenic Ascomycete causing the damaging Corynespora Leaf Fall (CLF) disease in rubber tree (Hevea brasiliensis). A small secreted glycoprotein named cassiicolin was previously described as an important effector of C. cassiicola. In this study, the diversity of the cassiicolin-encoding gene was analysed in C. cassiicola isolates sampled from various hosts and geographical origins. A cassiicolin gene was detected in 47 % of the isolates, encoding up to six distinct protein isoforms. In three isolates, two gene variants encoding cassiicolin isoforms Cas2 and Cas6 were found in the same isolate. A phylogenetic tree based on four combined loci and elucidating the diversity of the whole collection was strongly structured by the toxin class, as defined by the cassiicolin isoform. The isolates carrying the Cas1 gene (toxin class Cas1), all grouped in the same highly supported clade, were found the most aggressive on two rubber tree cultivars. Some isolates in which no Cas gene was detected could nevertheless generate moderate symptoms, suggesting the existence of other yet uncharacterized effectors. This study provides a useful base for future studies of C. cassiicola population biology and epidemiological surveys in various host plants. PMID:24433675

  5. Characterization and application of a novel class II thermophilic peroxidase from Myceliophthora thermophila in biosynthesis of polycatechol.

    PubMed

    Zerva, Anastasia; Christakopoulos, Paul; Topakas, Evangelos

    2015-01-01

    A peroxidase from the thermophilic fungus Myceliophthora thermophila that belongs to ascomycete Class II based on PeroxiBase classification was functionally expressed in methylotrophic yeast Pichia pastoris. The putative peroxidase from the genomic DNA was successfully cloned in P. pastoris X-33 under the transcriptional control of the alcohol oxidase (AOX1) promoter. The heterologous production was greatly enhanced by the addition of hemin with a titer of 0.41 U mL(-1) peroxidase activity at the second day of incubation. The recombinant enzyme was purified to homogeneity (50 kDa) and characterized using a series of phenolic substrates that indicated similar characteristics with those of generic peroxidases. In addition, the enzyme was found thermostable, retaining its activity for temperatures up to 60 °C after eight hours incubation. Moreover, the enzyme displayed remarkable H2O2 stability, retaining more than 80% of its initial activity after 24h incubation in 5000-fold molar excess of H2O2. The ability of the peroxidase to polymerize catechol at high superoxide concentrations, together with its high thermostability and substrate specificity, indicate a potential commercial significance of the enzyme. PMID:26047916

  6. Can vessel dimension explain tolerance toward fungal vascular wilt diseases in woody plants? Lessons from Dutch elm disease and esca disease in grapevine.

    PubMed

    Pouzoulet, Jérôme; Pivovaroff, Alexandria L; Santiago, Louis S; Rolshausen, Philippe E

    2014-01-01

    This review illuminates key findings in our understanding of grapevine xylem resistance to fungal vascular wilt diseases. Grapevine (Vitis spp.) vascular diseases such as esca, botryosphaeria dieback, and eutypa dieback, are caused by a set of taxonomically unrelated ascomycete fungi. Fungal colonization of the vascular system leads to a decline of the plant host because of a loss of the xylem function and subsequent decrease in hydraulic conductivity. Fungal vascular pathogens use different colonization strategies to invade and kill their host. Vitis vinifera cultivars display different levels of tolerance toward vascular diseases caused by fungi, but the plant defense mechanisms underlying those observations have not been completely elucidated. In this review, we establish a parallel between two vascular diseases, grapevine esca disease and Dutch elm disease, and argue that the former should be viewed as a vascular wilt disease. Plant genotypes exhibit differences in xylem morphology and resistance to fungal pathogens causing vascular wilt diseases. We provide evidence that the susceptibility of three commercial V. vinifera cultivars to esca disease is correlated to large vessel diameter. Additionally, we explore how xylem morphological traits related to water transport are influenced by abiotic factors, and how these might impact host tolerance of vascular wilt fungi. Finally, we explore the utility of this concept for predicting which V. vinifera cultivars are most vulnerable of fungal vascular wilt diseases and propose new strategies for disease management. PMID:24971084

  7. Comparative genomics of xylose-fermenting fungi for enhanced biofuel production

    SciTech Connect

    Wohlbach, Dana J.; Kuo, Alan; Sato, Trey K.; Potts, Katlyn M.; Salamov, Asaf A.; LaButti, Kurt M.; Sun, Hui; Clum, Alicia; Pangilinan, Jasmyn L.; Lindquist, Erika A.; Lucas, Susan; Lapidus, Alla; Jin, Mingjie; Gunawan, Christa; Balan, Venkatesh; Dale, Bruce E.; Jeffries, Thomas W.; Zinkel, Robert; Barry, Kerrie W.; Grigoriev, Igor V.; Gasch, Audrey P.

    2011-02-24

    Cellulosic biomass is an abundant and underused substrate for biofuel production. The inability of many microbes to metabolize the pentose sugars abundant within hemicellulose creates specific challenges for microbial biofuel production from cellulosic material. Although engineered strains of Saccharomyces cerevisiae can use the pentose xylose, the fermentative capacity pales in comparison with glucose, limiting the economic feasibility of industrial fermentations. To better understand xylose utilization for subsequent microbial engineering, we sequenced the genomes of two xylose-fermenting, beetle-associated fungi, Spathaspora passalidarum and Candida tenuis. To identify genes involved in xylose metabolism, we applied a comparative genomic approach across 14 Ascomycete genomes, mapping phenotypes and genotypes onto the fungal phylogeny, and measured genomic expression across five Hemiascomycete species with different xylose-consumption phenotypes. This approach implicated many genes and processes involved in xylose assimilation. Several of these genes significantly improved xylose utilization when engineered into S. cerevisiae, demonstrating the power of comparative methods in rapidly identifying genes for biomass conversion while reflecting on fungal ecology.

  8. Fungal community dynamics in relation to substrate quality of decaying Norway spruce ( Picea abies [L.] Karst.) logs in boreal forests.

    PubMed

    Rajala, Tiina; Peltoniemi, Mikko; Pennanen, Taina; Mäkipää, Raisa

    2012-08-01

    Decaying wood plays an important role in forest biodiversity, nutrient cycling and carbon balance. Community structure of wood-inhabiting fungi changes with mass loss of wood, but the relationship between substrate quality and decomposers is poorly understood. This limits the extent to which these ecosystem services can be effectively managed. We studied the fungal community and physico-chemical quality (stage of decay, dimensions, density, moisture, C : N ratio, lignin and water or ethanol extractives) of 543 Norway spruce logs in five unmanaged boreal forest sites of southern Finland. Fungi were identified using denaturing gradient gel electrophoresis and sequencing of DNA extracted directly from wood samples. Macroscopic fruiting bodies were also recorded. Results showed a fungal community succession with decreasing wood density and C : N ratio, and increasing moisture and lignin content. Fungal diversity peaked in the most decayed substrates. Ascomycetes typically colonized recently fallen wood. Brown-rot fungi preferred the intermediate decay stages. White-rot fungi represented approximately one-fifth of sequenced species in all decay phases excluding the final phase, where ectomycorrhizal (ECM) fungi became dominant. Lignin content of logs with white-rot fungi was low, and ECM fungi were associated with substrates containing abundant nitrogen. Macroscopic fruiting bodies were observed for only a small number of species detected with molecular techniques. PMID:22458543

  9. The endocytic adaptor proteins of pathogenic fungi: charting new and familiar pathways

    PubMed Central

    WANG, PING; SHEN, GUI

    2012-01-01

    Intracellular transport is an essential biological process that is highly conserved throughout the eukaryotic organisms. In fungi, adaptor proteins implicated in the endocytic cycle of endocytosis and exocytosis were found to be important for growth, differentiation, and/or virulence. For example, Saccharomyces cerevisiae Pan1 is an endocytic protein that regulates membrane trafficking, the actin cytoskeleton, and signaling. In Cryptococcus neoformans, a multi-modular endocytic protein, Cin1, was recently found to have pleiotropic functions in morphogenesis, endocytosis, exocytosis, and virulence. Interestingly, Cin1 is homologous to human intersectin ITSN1, but homologs of Cin1/ITSN1 were not found in ascomycetous S. cerevisiae and Candida albicans, or zygomycetous fungi. Moreover, an Eps15 protein homologous to S. cerevisiae Pan1/Ede1 and additional relevant protein homologs were identified in C. neoformans, suggesting the existence of either a distinct endocytic pathway mediated by Cin1 or pathways by either Cin1 or/and Pan1/Ede1 homologs. Whether and how the Cin1-mediated endocytic pathway represents a unique role in pathogenesis or reflects a redundancy of a transport apparatus remains an open and challenging question. This review discusses recent findings of endocytic adaptor proteins from pathogenic fungi and provides a perspective for novel endocytic machinery operating in C. neoformans. An understanding of intracellular trafficking mechanisms as they relate to pathogenesis will likely reveal the identity of novel antifungal targets. PMID:21254965

  10. Recombinant Expression of a Novel Fungal Immunomodulatory Protein with Human Tumor Cell Antiproliferative Activity from Nectria haematococca

    PubMed Central

    Li, Shuying; Nie, Ying; Ding, Yang; Shi, Lijun; Tang, Xuanming

    2014-01-01

    To our best knowledge, all of the fungal immunomodulatory proteins (FIPs) have been successfully extracted and identified in Basidomycetes, with only the exception of FIP from ascomycete Nectria haematococca (FIP-nha) discovered through homology alignment most recently. In this work, a gene encoding FIP-nha was synthesized and recombinantly expressed in an Escherichia coli expression system. SDS-PAGE and MALDI-MS analyses of recombinant FIP-nha (rFIP-nha) indicated that the gene was successfully expressed. The yield of the bioactive FIP-nha protein was 42.7 mg/L. In vitro assays of biological activity indicated that the rFIP-nha caused hemagglutination of human and rabbit red blood cells, significantly stimulated mouse spleen lymphocyte proliferation, and enhanced expression of interleukin-2 (IL-2) released from mouse splenocytes, revealing a strong antitumor effect against HL60, HepG2 and MGC823. Through this work, we constructed a rapid and efficient method of FIP production, and suggested that FIP-nha is a valuable candidate for use in future medical care and pharmaceutical products. PMID:25272229

  11. Characterization of chasmoendolithic community in Miers Valley, McMurdo Dry Valleys, Antarctica.

    PubMed

    Yung, Charmaine C M; Chan, Yuki; Lacap, Donnabella C; Pérez-Ortega, Sergio; de Los Rios-Murillo, Asuncion; Lee, Charles K; Cary, S Craig; Pointing, Stephen B

    2014-08-01

    The Antarctic Dry Valleys are unable to support higher plant and animal life and so microbial communities dominate biotic ecosystem processes. Soil communities are well characterized, but rocky surfaces have also emerged as a significant microbial habitat. Here, we identify extensive colonization of weathered granite on a landscape scale by chasmoendolithic microbial communities. A transect across north-facing and south-facing slopes plus valley floor moraines revealed 30-100 % of available substrate was colonized up to an altitude of 800 m. Communities were assessed at a multidomain level and were clearly distinct from those in surrounding soils and other rock-inhabiting cryptoendolithic and hypolithic communities. All colonized rocks were dominated by the cyanobacterial genus Leptolyngbya (Oscillatoriales), with heterotrophic bacteria, archaea, algae, and fungi also identified. Striking patterns in community distribution were evident with regard to microclimate as determined by aspect. Notably, a shift in cyanobacterial assemblages from Chroococcidiopsis-like phylotypes (Pleurocapsales) on colder-drier slopes, to Synechococcus-like phylotypes (Chroococcales) on warmer-wetter slopes. Greater relative abundance of known desiccation-tolerant bacterial taxa occurred on colder-drier slopes. Archaeal phylotypes indicated halotolerant taxa and also taxa possibly derived from nearby volcanic sources. Among the eukaryotes, the lichen photobiont Trebouxia (Chlorophyta) was ubiquitous, but known lichen-forming fungi were not recovered. Instead, fungal assemblages were dominated by ascomycetous yeasts. We conclude that chasmoendoliths likely constitute a significant geobiological phenomenon at lower elevations in granite-dominated Antarctic Dry Valley systems. PMID:24671755

  12. Sequencing and annotation of the Ophiostoma ulmi genome

    PubMed Central

    2013-01-01

    Background The ascomycete fungus Ophiostoma ulmi was responsible for the initial pandemic of the massively destructive Dutch elm disease in Europe and North America in early 1910. Dutch elm disease has ravaged the elm tree population globally and is a major threat to the remaining elm population. O. ulmi is also associated with valuable biomaterials applications. It was recently discovered that proteins from O. ulmi can be used for efficient transformation of amylose in the production of bioplastics. Results We have sequenced the 31.5 Mb genome of O.ulmi using Illumina next generation sequencing. Applying both de novo and comparative genome annotation methods, we predict a total of 8639 gene models. The quality of the predicted genes was validated using a variety of data sources consisting of EST data, mRNA-seq data and orthologs from related fungal species. Sequence-based computational methods were used to identify candidate virulence-related genes. Metabolic pathways were reconstructed and highlight specific enzymes that may play a role in virulence. Conclusions This genome sequence will be a useful resource for further research aimed at understanding the molecular mechanisms of pathogenicity by O. ulmi. It will also facilitate the identification of enzymes necessary for industrial biotransformation applications. PMID:23496816

  13. Temporal variation in mycorrhizal diversity and carbon and nitrogen stable isotope abundance in the wintergreen meadow orchid Anacamptis morio.

    PubMed

    Ercole, Enrico; Adamo, Martino; Rodda, Michele; Gebauer, Gerhard; Girlanda, Mariangela; Perotto, Silvia

    2015-02-01

    Many adult orchids, especially photoautotrophic species, associate with a diverse range of mycorrhizal fungi, but little is known about the temporal changes that might occur in the diversity and functioning of orchid mycorrhiza during vegetative and reproductive plant growth. Temporal variations in the spectrum of mycorrhizal fungi and in stable isotope natural abundance were investigated in adult plants of Anacamptis morio, a wintergreen meadow orchid. Anacamptis morio associated with mycorrhizal fungi belonging to Tulasnella, Ceratobasidium and a clade of Pezizaceae (Ascomycetes). When a complete growing season was investigated, multivariate analyses indicated significant differences in the mycorrhizal fungal community. Among fungi identified from manually isolated pelotons, Tulasnella was more common in autumn and winter, the pezizacean clade was very frequent in spring, and Ceratobasidium was more frequent in summer. By contrast, relatively small variations were found in carbon (C) and nitrogen (N) stable isotope natural abundance, A. morio samples showing similar (15)N enrichment and (13)C depletion at the different sampling times. These observations suggest that, irrespective of differences in the seasonal environmental conditions, the plant phenological stages and the associated fungi, the isotopic content in mycorrhizal A. morio remains fairly constant over time. PMID:25382295

  14. The ecological implications of a Yakutian mammoth's last meal

    NASA Astrophysics Data System (ADS)

    van Geel, Bas; Aptroot, André; Baittinger, Claudia; Birks, Hilary H.; Bull, Ian D.; Cross, Hugh B.; Evershed, Richard P.; Gravendeel, Barbara; Kompanje, Erwin J. O.; Kuperus, Peter; Mol, Dick; Nierop, Klaas G. J.; Pals, Jan Peter; Tikhonov, Alexei N.; van Reenen, Guido; van Tienderen, Peter H.

    2008-05-01

    Part of a large male woolly mammoth ( Mammuthus primigenius) was preserved in permafrost in northern Yakutia. It was radiocarbon dated to ca. 18,500 14C yr BP (ca. 22,500 cal yr BP). Dung from the lower intestine was subjected to a multiproxy array of microscopic, chemical, and molecular techniques to reconstruct the diet, the season of death, and the paleoenvironment. Pollen and plant macro-remains showed that grasses and sedges were the main food, with considerable amounts of dwarf willow twigs and a variety of herbs and mosses. Analyses of 110-bp fragments of the plastid rbcL gene amplified from DNA and of organic compounds supplemented the microscopic identifications. Fruit-bodies of dung-inhabiting Ascomycete fungi which develop after at least one week of exposure to air were found inside the intestine. Therefore the mammoth had eaten dung. It was probably mammoth dung as no bile acids were detected among the fecal biomarkers analysed. The plant assemblage and the presence of the first spring vessels of terminal tree-rings of dwarf willows indicated that the animal died in early spring. The mammoth lived in extensive cold treeless grassland vegetation interspersed with wetter, more productive meadows. The study demonstrated the paleoecological potential of several biochemical analytical techniques.

  15. Extremophilic fungi in arctic ice: a relationship between adaptation to low temperature and water activity

    NASA Astrophysics Data System (ADS)

    Gunde-Cimerman, N.; Sonjak, S.; Zalar, P.; Frisvad, J. C.; Diderichsen, B.; Plemenitaš, A.

    Little is known about fungal diversity in extremely cold regions. Low temperatures induce the formation of ice crystals and therefore also the creation of low water activity ( aw). These are the dominant factors in external chemistry that influence microbial biota in cold regions. Therefore, we have used selective low water activity media plus low incubation temperatures for the isolation of fungi from an Arctic environment. In comparison with the highest values of colony forming units (CFU) obtained on mesophilic media, considerably higher fungal CFU per litre of water were detected on low aw media, ranging from 1000 to 3000 l -1 in seawater, 6000 to 7000 l -1 in melted sea ice and up to 13,000 l -1 in melted glacier ice. The dominant taxa were ascomycetous and basidiomycetous yeasts, melanized fungi, mainly represented by the genera Cladosporium and Aureobasidium plus different species of the genus Penicillium. Preliminary taxonomic analyses revealed several new species and varieties. Further characterisations are needed to determine whether this diversity is due to geographic isolation, ecological conditions or independent evolutionary origin.

  16. Ectomycorrhizal fungal communities of Coccoloba uvifera (L.) L. mature trees and seedlings in the neotropical coastal forests of Guadeloupe (Lesser Antilles).

    PubMed

    Séne, Seynabou; Avril, Raymond; Chaintreuil, Clémence; Geoffroy, Alexandre; Ndiaye, Cheikh; Diédhiou, Abdala Gamby; Sadio, Oumar; Courtecuisse, Régis; Sylla, Samba Ndao; Selosse, Marc-André; Bâ, Amadou

    2015-10-01

    We studied belowground and aboveground diversity and distribution of ectomycorrhizal (EM) fungal species colonizing Coccoloba uvifera (L.) L. (seagrape) mature trees and seedlings naturally regenerating in four littoral forests of the Guadeloupe island (Lesser Antilles). We collected 546 sporocarps, 49 sclerotia, and morphotyped 26,722 root tips from mature trees and seedlings. Seven EM fungal species only were recovered among sporocarps (Cantharellus cinnabarinus, Amanita arenicola, Russula cremeolilacina, Inocybe littoralis, Inocybe xerophytica, Melanogaster sp., and Scleroderma bermudense) and one EM fungal species from sclerotia (Cenococcum geophilum). After internal transcribed spacer (ITS) sequencing, the EM root tips fell into 15 EM fungal taxa including 14 basidiomycetes and 1 ascomycete identified. Sporocarp survey only weakly reflected belowground assessment of the EM fungal community, although 5 fruiting species were found on roots. Seagrape seedlings and mature trees had very similar communities of EM fungi, dominated by S. bermudense, R. cremeolilacina, and two Thelephoraceae: shared species represented 93 % of the taxonomic EM fungal diversity and 74 % of the sampled EM root tips. Furthermore, some significant differences were observed between the frequencies of EM fungal taxa on mature trees and seedlings. The EM fungal community composition also varied between the four investigated sites. We discuss the reasons for such a species-poor community and the possible role of common mycorrhizal networks linking seagrape seedlings and mature trees in regeneration of coastal forests. PMID:25711744

  17. Compartmentalized and contrasted response of ectomycorrhizal and soil fungal communities of Scots pine forests along elevation gradients in France and Spain.

    PubMed

    Rincón, Ana; Santamaría-Pérez, Blanca; Rabasa, Sonia G; Coince, Aurore; Marçais, Benoit; Buée, Marc

    2015-08-01

    Fungi are principal actors of forest soils implied in many ecosystem services and the mediation of tree's responses. Forecasting fungal responses to environmental changes is necessary for maintaining forest productivity, although our partial understanding of how abiotic and biotic factors affect fungal communities is restricting the predictions. We examined fungal communities of Pinus sylvestris along elevation gradients to check potential responses to climate change-associated factors. Fungi of roots and soils were analysed at a regional scale, by using a high-throughput sequencing approach. Overall soil fungal richness increased with pH, whereas it did not vary with climate. However, when representative sub-assemblages, i.e. Ascomycetes/Basidiomycetes, and families were analysed, they differentially answered to climatic and edaphic variables. This response was dependent on where they settled, i.e. soil versus roots, and/or on their lifestyle, i.e. mycorrhizal or not, suggesting different potential functional weights within the community. Our results revealed a highly compartmentalized and contrasted response of fungal communities in forest soils. The different response of fungal sub-assemblages indicated a range of possible selective direct and indirect (i.e. via host) impacts of climatic variations on these communities, of unknown functional consequences, that helps in understanding potential fungal responses under future global change scenarios. PMID:25953485

  18. Isolation, structure elucidation and antibacterial activity of a new tetramic acid, ascosetin.

    PubMed

    Ondeyka, John G; Smith, Scott K; Zink, Deborah L; Vicente, Francisca; Basilio, Angela; Bills, Gerald F; Polishook, Jon D; Garlisi, Charles; Mcguinness, Debra; Smith, Elizabeth; Qiu, Hongchen; Gill, Charles J; Donald, Robert G K; Phillips, John W; Goetz, Michael A; Singh, Sheo B

    2014-07-01

    The ever-increasing bacterial resistance to clinical antibiotics is making many drugs ineffective and creating significant treatment gaps. This can be only circumvented by the discovery of antibiotics with new mechanisms of action. We report here the identification of a new tetramic acid, ascosetin, from an Ascomycete using the Staphylococcus aureus fitness test screening method. The structure was elucidated by spectroscopic methods including 2D NMR and HRMS. Relative stereochemistry was determined by ROESY and absolute configuration was deduced by comparative CD spectroscopy. Ascosetin inhibited bacterial growth with 2-16 ?g ml(-1) MIC values against Gram-positive strains including methicillin-resistant S. aureus. It also inhibited the growth of Haemophilus influenzae with a MIC value of 8 ?g ml(-1). It inhibited DNA, RNA, protein and lipid synthesis with similar IC50 values, suggesting a lack of specificity; however, it produced neither bacterial membrane nor red blood cell lysis. It showed selectivity for bacterial growth inhibition compared with fungal but not mammalian cells. The isolation, structure and biological activity of ascosetin have been detailed here. PMID:24690911

  19. Metagenome sequence of Elaphomyces granulatus from sporocarp tissue reveals Ascomycota ectomycorrhizal fingerprints of genome expansion and a Proteobacteria-rich microbiome.

    PubMed

    Quandt, C Alisha; Kohler, Annegret; Hesse, Cedar N; Sharpton, Thomas J; Martin, Francis; Spatafora, Joseph W

    2015-08-01

    Many obligate symbiotic fungi are difficult to maintain in culture, and there is a growing need for alternative approaches to obtaining tissue and subsequent genomic assemblies from such species. In this study, the genome of Elaphomyces granulatus was sequenced from sporocarp tissue. The genome assembly remains on many contigs, but gene space is estimated to be mostly complete. Phylogenetic analyses revealed that the Elaphomyces lineage is most closely related to Talaromyces and Trichocomaceae s.s. The genome of E.?granulatus is reduced in carbohydrate-active enzymes, despite a large expansion in genome size, both of which are consistent with what is seen in Tuber melanosporum, the other sequenced ectomycorrhizal ascomycete. A large number of transposable elements are predicted in the E.?granulatus genome, especially Gypsy-like long terminal repeats, and there has also been an expansion in helicases. The metagenome is a complex community dominated by bacteria in Bradyrhizobiaceae, and there is evidence to suggest that the community may be reduced in functional capacity as estimated by KEGG pathways. Through the sequencing of sporocarp tissue, this study has provided insights into Elaphomyces phylogenetics, genomics, metagenomics and the evolution of the ectomycorrhizal association. PMID:25753751

  20. Evolution of host breadth in broad interactions: mycorrhizal specificity in East Asian and North American rattlesnake plantains (Goodyera spp.) and their fungal hosts.

    PubMed

    Shefferson, Richard P; Cowden, Charles C; McCormick, Melissa K; Yukawa, Tomohisa; Ogura-Tsujita, Yuki; Hashimoto, Toshimasa

    2010-07-01

    Host breadth is often assumed to have no evolutionary significance in broad interactions because of the lack of cophylogenetic patterns between interacting species. Nonetheless, the breadth and suite of hosts utilized by one species may have adaptive value, particularly if it underlies a common ecological niche among hosts. Here, we present a preliminary assessment of the evolution of mycorrhizal specificity in 12 closely related orchid species (genera Goodyera and Hetaeria) using DNA-based methods. We mapped specificity onto a plant phylogeny that we estimated to infer the evolutionary history of the mycorrhiza from the plant perspective, and hypothesized that phylogeny would explain a significant portion of the variance in specificity of plants on their host fungi. Sampled plants overwhelmingly associated with genus Ceratobasidium, but also occasionally with some ascomycetes. Ancestral mycorrhizal specificity was narrow in the orchids, and broadened rarely as Goodyera speciated. Statistical tests of phylogenetic inertia suggested some support for specificity varying with increasing phylogenetic distance, though only when the phylogenetic distance between suites of fungi interacting with each plant taxon were taken into account. These patterns suggest a role for phylogenetic conservatism in maintaining suits of fungal hosts among plants. We stress the evolutionary importance of host breadth in these organisms, and suggest that even generalists are likely to be constrained evolutionarily to maintaining associations with their symbionts. PMID:20584135

  1. High specificity generally characterizes mycorrhizal association in rare lady's slipper orchids, genus Cypripedium.

    PubMed

    Shefferson, Richard P; Weiss, Michael; Kull, Tiiu; Taylor, D Lee

    2005-02-01

    Lady's slipper orchids (Cypripedium spp.) are rare terrestrial plants that grow throughout the temperate Northern Hemisphere. Like all orchids, they require mycorrhizal fungi for germination and seedling nutrition. The nutritional relationships of adult Cypripedium mycorrhizae are unclear; however, Cypripedium distribution may be limited by mycorrhizal specificity, whether this specificity occurs only during the seedling stage or carries on into adulthood. We attempted to identify the primary mycorrhizal symbionts for 100 Cypripedium plants, and successfully did so with two Cypripedium calceolus, 10 Cypripedium californicum, six Cypripedium candidum, 16 Cypripedium fasciculatum, two Cypripedium guttatum, 12 Cypripedium montanum, and 11 Cypripedium parviflorum plants from a total of 44 populations in Europe and North America, yielding fungal nuclear large subunit and mitochondrial large subunit sequence and RFLP (restriction fragment length polymorphism) data for 59 plants. Because orchid mycorrhizal fungi are typically observed without fruiting structures, we assessed fungal identity through direct PCR (polymerase chain reaction) amplification of fungal genes from mycorrhizally colonized root tissue. Phylogenetic analysis revealed that the great majority of Cypripedium mycorrhizal fungi are members of narrow clades within the fungal family Tulasnellaceae. Rarely occurring root endophytes include members of the Sebacinaceae, Ceratobasidiaceae, and the ascomycetous genus, Phialophora. C. californicum was the only orchid species with apparently low specificity, as it associated with tulasnelloid, ceratobasidioid, and sebacinoid fungi in roughly equal proportion. Our results add support to the growing literature showing that high specificity is not limited to nonphotosynthetic plants, but also occurs in photosynthetic ones. PMID:15660950

  2. Deciphering the uniqueness of Mucoromycotina cell walls by combining biochemical and phylogenomic approaches.

    PubMed

    Mélida, Hugo; Sain, Divya; Stajich, Jason E; Bulone, Vincent

    2015-05-01

    Most fungi from the Mucoromycotina lineage occur in ecosystems as saprobes, although some species are phytopathogens or may induce human mycosis. Mucoromycotina represent early diverging models that are most valuable for understanding fungal evolution. Here we reveal the uniqueness of the cell wall structure of the Mucoromycotina Rhizopus oryzae and Phycomyces blakesleeanus compared with the better characterized cell wall of the ascomycete Neurospora crassa. We have analysed the corresponding polysaccharide biosynthetic and modifying pathways, and highlight their evolutionary features and higher complexity in terms of gene copy numbers compared with species from other lineages. This work uncovers the presence in Mucoromycotina of abundant fucose-based polysaccharides similar to algal fucoidans. These unexpected polymers are associated with unusually low amounts of glucans and a higher proportion of chitin compared with N.?crassa. The specific structural features are supported by the identification of genes potentially involved in the corresponding metabolic pathways. Phylogenomic analyses of genes encoding carbohydrate synthases, polysaccharide modifying enzymes and enzymes involved in nucleotide-sugar formation provide evidence for duplication events during evolution of cell wall metabolism in fungi. Altogether, the data highlight the specificity of Mucoromycotina cell walls and pave the way for a finer understanding of their metabolism. PMID:25143134

  3. Biocontrol of Bactrocera oleae (Diptera: Tephritidae) with Metarhizium brunneum and its extracts.

    PubMed

    Yousef, M; Lozano-Tovar, M D; Garrido-Jurado, I; Quesada-Moraga, E

    2013-06-01

    The susceptibility of preimaginal and adult olive fruit fly, Bactrocera oleae (Gmelin) (Diptera: Tephritidae), to a strain of the mitosporic ascomycete Metarhizium brunneum (Petch) (Hypocreales: Clavicipitaceae) and the insecticidal activity of its crude extract to olive fruit fly adults were investigated. Strain EAMb 09/01-Su caused 60% mortality to B. oleae adults, with average survival time (AST) of 8.8 d. In soil treatments against pupariating third-instar larvae, preimaginal B. oleae mortality reached 82.3%, whereas preimaginal mortality targeting puparia was 33.3%. The crude extract of EAMb 09/01-Su strain caused 80.0% adult mortality when administered per os, with AST of 27.7 h. The crude extract was demonstrated to be quite thermostable and photoresistant. These results indicate that M. brunneum EAMb 09/01-Su strain and its crude extract show potential to be used in an integrated pest management olive fruit fly management strategy targeting both adults and preimaginals. PMID:23865175

  4. Impact of the competition between mating types on the cultivation of Tuber melanosporum: Romeo and Juliet and the matter of space and time.

    PubMed

    Rubini, Andrea; Riccioni, Claudia; Belfiori, Beatrice; Paolocci, Francesco

    2014-04-01

    Major breakthroughs in our understanding of the life cycles of the symbiotic ascomycetes belonging to the genus Tuber have occurred over the last several years. A number of Tuber species produce edible fruiting bodies, known as truffles, that are marketed worldwide. A better understanding of the basic biological characteristics of Tuber spp. is likely to have tremendous practical relevance for their cultivation. Tuber melanosporum produces the most valuable black truffles and its genome has been recently sequenced. This species is now serving as a model for studying the biology of truffles. Here, we review recent progress in the understanding of sexual reproduction modalities in T. melanosporum. The practical relevance of these findings is outlined. In particular, the discoveries that T. melanosporum is heterothallic and that strains of different mating types compete to persist on the roots of host plants suggest that the spatial and temporal distributional patterns of strains of different mating types are key determinants of truffle fructification. The spatial segregation of the two mating types in areas where T. melanosporum occurs likely limits truffle production. Thus, host plant inoculation techniques and agronomic practices that might be pursued to manage T. melanosporum orchards with a balanced presence of the two mating partners are described. PMID:24384788

  5. Sea foam as a source of fungal inoculum for the isolation of biologically active natural products

    PubMed Central

    Overy, David P.; Berrue, Fabrice; Correa, Hebelin; Hanif, Novriyandi; Hay, Kathryn; Lanteigne, Martin; Mquilian, Kathrine; Duffy, Stephanie; Boland, Patricia; Jagannathan, Ramesh; Carr, Gavin S.; Vansteeland, Marieke; Kerr, Russell G.

    2014-01-01

    Due to a rate increase in the resistance of microbial pathogens to currently used antibiotics, there is a need in society for the discovery of novel antimicrobials. Historically, fungi are a proven source for antimicrobial compounds. The main goals of this study were to investigate the fungal diversity associated with sea foam collected around the coast of Prince Edward Island and the utility of this resource for the production of antimicrobial natural products. Obtained isolates were identified using ITS and nLSU rDNA sequences, fermented on four media, extracted and fractions enriched in secondary metabolites were screened for antimicrobial activity. The majority of the isolates obtained were ascomycetes, consisting of four recognized marine taxa along with other ubiquitous genera and many ‘unknown’ isolates that could not be identified to the species level using rDNA gene sequences. Secondary metabolite isolation efforts lead to the purification of the metabolites epolones A and B, pycnidione and coniothyrione from a strain of Neosetophoma samarorum; brefeldin A, leptosin J and the metabolite TMC-264 from an unknown fungus (probably representative of an Edenia sp.); and 1-hydroxy-6-methyl-8-hydroxymethylxanthone, chrysophanol and chrysophanol bianthrone from a Phaeospheria spartinae isolate. The biological activity of each of these metabolites was assessed against a panel of microbial pathogens as well as several cell lines. PMID:25379337

  6. Application of temperature gradient gel electrophoresis to the study of yeast diversity in the estuary of the Tagus river, Portugal.

    PubMed

    Gadanho, Mário; Sampaio, José Paulo

    2004-12-01

    Temperature gradient gel electrophoresis (TGGE) was employed for the assessment of yeast diversity in the estuary of the Tagus river (Portugal). The molecular detection of yeasts was carried out directly from water samples and, in parallel, a cultivation approach by means of an enrichment step was employed. A nested PCR was employed to obtain a fungal amplicon containing the D2 domain of the 26S rRNA gene. For identification the TGGE bands were extracted, re-amplified, and sequenced. Fourteen fungal taxa were detected and all except one were yeasts. Most yeast sequences corresponded to members of the Ascomycota and only three belonged to the Basidiomycota. Five yeasts (four ascomycetes and one basidiomycete) could not be identified to the species level due to the uniqueness of their sequences. The number of species detected after enrichment was higher than the number of taxa found using the direct detection method. This suggests that some yeast populations are present in densities that are below the detection threshold of the method. With respect to the analysis of the yeast community structure, our results indicate that the dominant populations belong to Debaryomyces hansenii, Rhodotorula mucilaginosa, Cryptococcus longus, and to an uncultured basidiomycetous yeast phylogenetically close to Cr. longus. The combined analysis of direct detection and cultivation approaches indicates a similar community structure at the two sampled sites since nine species were present at both localities. PMID:15556087

  7. Candidate effector proteins of the necrotrophic apple canker pathogen Valsa mali can suppress BAX-induced PCD

    PubMed Central

    Li, Zhengpeng; Yin, Zhiyuan; Fan, Yanyun; Xu, Ming; Kang, Zhensheng; Huang, Lili

    2015-01-01

    Canker caused by the Ascomycete Valsa mali is the most destructive disease of apple in Eastern Asia, resulting in yield losses of up to 100%. This necrotrophic fungus induces severe necrosis on apple, eventually leading to the death of the whole tree. Identification of necrosis inducing factors may help to unravel the molecular bases for colonization of apple trees by V. mali. As a first step toward this goal, we identified and characterized the V. mali repertoire of candidate effector proteins (CEPs). In total, 193 secreted proteins with no known function were predicted from genomic data, of which 101 were V. mali-specific. Compared to non-CEPs predicted for the V. mali secretome, CEPs have shorter sequence length and a higher content of cysteine residues. Based on transient over-expression in Nicotiana benthamiana performed for 70 randomly selected CEPs, seven V. mali Effector Proteins (VmEPs) were shown to significantly suppress BAX-induced PCD. Furthermore, targeted deletion of VmEP1 resulted in a significant reduction of virulence. These results suggest that V. mali expresses secreted proteins that can suppress PCD usually associated with effector-triggered immunity (ETI). ETI in turn may play an important role in the V. mali–apple interaction. The ability of V. mali to suppress plant ETI sheds a new light onto the interaction of a necrotrophic fungus with its host plant. PMID:26284095

  8. Fungal Community Shifts in Structure and Function across a Boreal Forest Fire Chronosequence.

    PubMed

    Sun, Hui; Santalahti, Minna; Pumpanen, Jukka; Köster, Kajar; Berninger, Frank; Raffaello, Tommaso; Jumpponen, Ari; Asiegbu, Fred O; Heinonsalo, Jussi

    2015-11-15

    Forest fires are a common natural disturbance in forested ecosystems and have a large impact on the microbial communities in forest soils. The response of soil fungal communities to forest fire is poorly documented. Here, we investigated fungal community structure and function across a 152-year boreal forest fire chronosequence using high-throughput sequencing of the internal transcribed spacer 2 (ITS2) region and a functional gene array (GeoChip). Our results demonstrate that the boreal forest soil fungal community was most diverse soon after a fire disturbance and declined over time. The differences in the fungal communities were explained by changes in the abundance of basidiomycetes and ascomycetes. Ectomycorrhizal (ECM) fungi contributed to the increase in basidiomycete abundance over time, with the operational taxonomic units (OTUs) representing the genera Cortinarius and Piloderma dominating in abundance. Hierarchical cluster analysis by using gene signal intensity revealed that the sites with different fire histories formed separate clusters, suggesting differences in the potential to maintain essential biogeochemical soil processes. The site with the greatest biological diversity had also the most diverse genes. The genes involved in organic matter degradation in the mature forest, in which ECM fungi were the most abundant, were as common in the youngest site, in which saprotrophic fungi had a relatively higher abundance. This study provides insight into the impact of fire disturbance on soil fungal community dynamics. PMID:26341215

  9. Genome Sequences of Three Phytopathogenic Species of the Magnaporthaceae Family of Fungi

    PubMed Central

    Okagaki, Laura H.; Nunes, Cristiano C.; Sailsbery, Joshua; Clay, Brent; Brown, Doug; John, Titus; Oh, Yeonyee; Young, Nelson; Fitzgerald, Michael; Haas, Brian J.; Zeng, Qiandong; Young, Sarah; Adiconis, Xian; Fan, Lin; Levin, Joshua Z.; Mitchell, Thomas K.; Okubara, Patricia A.; Farman, Mark L.; Kohn, Linda M.; Birren, Bruce; Ma, Li-Jun; Dean, Ralph A.

    2015-01-01

    Magnaporthaceae is a family of ascomycetes that includes three fungi of great economic importance: Magnaporthe oryzae, Gaeumannomyces graminis var. tritici, and Magnaporthe poae. These three fungi cause widespread disease and loss in cereal and grass crops, including rice blast disease (M. oryzae), take-all disease in wheat and other grasses (G. graminis), and summer patch disease in turf grasses (M. poae). Here, we present the finished genome sequence for M. oryzae and draft sequences for M. poae and G. graminis var. tritici. We used multiple technologies to sequence and annotate the genomes of M. oryzae, M. poae, and G. graminis var. tritici. The M. oryzae genome is now finished to seven chromosomes whereas M. poae and G. graminis var. tritici are sequenced to 40.0× and 25.0× coverage respectively. Gene models were developed by the use of multiple computational techniques and further supported by RNAseq data. In addition, we performed preliminary analysis of genome architecture and repetitive element DNA. PMID:26416668

  10. The freshwater sponge Ephydatia fluviatilis harbours diverse Pseudomonas species (Gammaproteobacteria, Pseudomonadales) with broad-spectrum antimicrobial activity.

    PubMed

    Keller-Costa, Tina; Jousset, Alexandre; van Overbeek, Leo; van Elsas, Jan Dirk; Costa, Rodrigo

    2014-01-01

    Bacteria are believed to play an important role in the fitness and biochemistry of sponges (Porifera). Pseudomonas species (Gammaproteobacteria, Pseudomonadales) are capable of colonizing a broad range of eukaryotic hosts, but knowledge of their diversity and function in freshwater invertebrates is rudimentary. We assessed the diversity, structure and antimicrobial activities of Pseudomonas spp. in the freshwater sponge Ephydatia fluviatilis. Polymerase Chain Reaction--Denaturing Gradient Gel Electrophoresis (PCR-DGGE) fingerprints of the global regulator gene gacA revealed distinct structures between sponge-associated and free-living Pseudomonas communities, unveiling previously unsuspected diversity of these assemblages in freshwater. Community structures varied across E. fluviatilis specimens, yet specific gacA phylotypes could be detected by PCR-DGGE in almost all sponge individuals sampled over two consecutive years. By means of whole-genome fingerprinting, 39 distinct genotypes were found within 90 fluorescent Pseudomonas isolates retrieved from E. fluviatilis. High frequency of in vitro antibacterial (49%), antiprotozoan (35%) and anti-oomycetal (32%) activities was found among these isolates, contrasting less-pronounced basidiomycetal (17%) and ascomycetal (8%) antagonism. Culture extracts of highly predation-resistant isolates rapidly caused complete immobility or lysis of cells of the protozoan Colpoda steinii. Isolates tentatively identified as P. jessenii, P. protegens and P. oryzihabitans showed conspicuous inhibitory traits and correspondence with dominant sponge-associated phylotypes registered by cultivation-independent analysis. Our findings suggest that E. fluviatilis hosts both transient and persistent Pseudomonas symbionts displaying antimicrobial activities of potential ecological and biotechnological value. PMID:24533086

  11. Patterns of major metabolites biosynthesis by different mushroom fungi grown on glucose-based submerged cultures.

    PubMed

    Diamantopoulou, Panagiota; Papanikolaou, Seraphim; Komaitis, Michael; Aggelis, George; Philippoussis, Antonios

    2014-07-01

    The biosynthetic potential of four basidiomycetes (Agrocybe aegerita, Flammulina velutipes, Ganoderma applanatum and Pleurotus pulmonarius) and one ascomycete (Morchella esculenta) was examined in regard to biomass, intracellular (endopolysaccharides and lipids) and extracellular (exopolysaccharides) compounds' production in liquid media with glucose as substrate, in static and agitated cultures. Exopolysaccharides' production presented significant negative correlation with biomass, endopolysaccharides and lipids, while biomass was positively related to the production of endopolysaccharides and lipids. Maximum values of biomass, endo- and exo-polysaccharides obtained were quite impressive: P. pulmonarius produced 22.5 g/L of biomass, A. aegerita 60.4 % (w/w) of endopolysaccharides and F. velutipes 1.2 g/L of exopolysaccharides. Polysaccharides and lipids synthesized at the early growth stages were subjected to degradation as the fermentation proceeded. Mycelial lipids of all strains were highly unsaturated, dominated by linoleic acid, whereas glucose was the main building block of endopolysaccharides. The ability of the examined mushroom fungi to synthesize in high quantities biomass and polysaccharides, products with biotechnological and medicinal interest, renders these fungi as potential candidates in sugar-based bio-refineries. PMID:24366161

  12. Fluorescent markers for the Spitzenkörper and exocytosis in Zymoseptoria tritici?

    PubMed Central

    Guo, M.; Kilaru, S.; Schuster, M.; Latz, M.; Steinberg, G.

    2015-01-01

    Fungal hyphae are highly polarized cells that invade their substrate by tip growth. In plant pathogenic fungi, hyphal growth is essential for host invasion. This makes polarity factors and secretion regulators potential new targets for novel fungicides. Polarization requires delivery of secretory vesicles to the apical Spitzenkörper, followed by polarized exocytosis at the expanding cell tip. Here, we introduce fluorescent markers to visualize the apical Spitzenkörper and the apical site of exocytosis in hyphae of the wheat pathogen Zymoseptoria tritici. We fused green fluorescent protein to the small GTPase ZtSec4, the myosin light chain ZtMlc1 and the small GTPase ZtRab11 and co-localize the fusion proteins with the dye FM4-64 in the hyphal apex, suggesting that the markers label the hyphal Spitzenkörper in Z. tritici. In addition, we localize GFP-fusions to the exocyst protein ZtExo70, the polarisome protein ZtSpa2. Consistent with results in the ascomycete Neurospora crassa, these markers did localize near the plasma membrane at the hyphal tip and only partially co-localize with FM4-64. Thus, these fluorescent markers are useful molecular tools that allow phenotypic analysis of mutants in Z. tritici. These tools will help develop new avenues of research in our quest to control STB infection in wheat. PMID:26092802

  13. Microbes are trophic analogs of animals.

    PubMed

    Steffan, Shawn A; Chikaraishi, Yoshito; Currie, Cameron R; Horn, Heidi; Gaines-Day, Hannah R; Pauli, Jonathan N; Zalapa, Juan E; Ohkouchi, Naohiko

    2015-12-01

    In most ecosystems, microbes are the dominant consumers, commandeering much of the heterotrophic biomass circulating through food webs. Characterizing functional diversity within the microbiome, therefore, is critical to understanding ecosystem functioning, particularly in an era of global biodiversity loss. Using isotopic fingerprinting, we investigated the trophic positions of a broad diversity of heterotrophic organisms. Specifically, we examined the naturally occurring stable isotopes of nitrogen ((15)N:(14)N) within amino acids extracted from proteobacteria, actinomycetes, ascomycetes, and basidiomycetes, as well as from vertebrate and invertebrate macrofauna (crustaceans, fish, insects, and mammals). Here, we report that patterns of intertrophic (15)N-discrimination were remarkably similar among bacteria, fungi, and animals, which permitted unambiguous measurement of consumer trophic position, independent of phylogeny or ecosystem type. The observed similarities among bacterial, fungal, and animal consumers suggest that within a trophic hierarchy, microbiota are equivalent to, and can be interdigitated with, macrobiota. To further test the universality of this finding, we examined Neotropical fungus gardens, communities in which bacteria, fungi, and animals are entwined in an ancient, quadripartite symbiosis. We reveal that this symbiosis is a discrete four-level food chain, wherein bacteria function as the apex carnivores, animals and fungi are meso-consumers, and the sole herbivores are fungi. Together, our findings demonstrate that bacteria, fungi, and animals can be integrated within a food chain, effectively uniting the macro- and microbiome in food web ecology and facilitating greater inclusion of the microbiome in studies of functional diversity. PMID:26598691

  14. Genetic engineering, high resolution mass spectrometry and nuclear magnetic resonance spectroscopy elucidate the bikaverin biosynthetic pathway in Fusarium fujikuroi.

    PubMed

    Arndt, Birgit; Studt, Lena; Wiemann, Philipp; Osmanov, Helena; Kleigrewe, Karin; Köhler, Jens; Krug, Isabel; Tudzynski, Bettina; Humpf, Hans-Ulrich

    2015-11-01

    Secondary metabolites of filamentous fungi can be highly bioactive, ranging from antibiotic to cancerogenic properties. In this study we were able to identify a new, yet unknown metabolite produced by Fusarium fujikuroi, an ascomycetous rice pathogen. With the help of genomic engineering and high-performance liquid chromatography (HPLC) coupled to high resolution mass spectrometry (HRMS) followed by isolation and detailed structure elucidation, the new substance could be designated as an unknown bikaverin precursor, missing two methyl- and one hydroxy group, hence named oxo-pre-bikaverin. Though the bikaverin gene cluster has been extensively studied in the past, elucidation of the biosynthetic pathway remained elusive due to a negative feedback loop that regulates the genes within the cluster. To decipher the bikaverin biosynthetic pathway and to overcome these negative regulation circuits, the structural cluster genes BIK2 and BIK3 were overexpressed independently in the ??BIK2/BIK3+OE::BIK1 mutant background by using strong constitutive promoters. Using the software tool MZmine 2, the metabolite profile of the generated mutants obtained by HPLC-HRMS was compared, revealing further intermediates. PMID:26382642

  15. Resistance and resilience responses of a range of soil eukaryote and bacterial taxa to fungicide application

    PubMed Central

    Howell, Christopher C.; Hilton, Sally; Semple, Kirk T.; Bending, Gary D.

    2014-01-01

    The application of plant protection products has the potential to significantly affect soil microbial community structure and function. However, the extent to which soil microbial communities from different trophic levels exhibit resistance and resilience to such compounds remains poorly understood. The resistance and resilience responses of a range of microbial communities (bacteria, fungi, archaea, pseudomonads, and nematodes) to different concentrations of the strobilurin fungicide, azoxystrobin were studied. A significant concentration-dependent decrease, and subsequent recovery in soil dehydrogenase activity was recorded, but no significant impact on total microbial biomass was observed. Impacts on specific microbial communities were studied using small subunit (SSU) rRNA terminal restriction fragment length polymorphism (T-RFLP) profiling using soil DNA and RNA. The application of azoxystrobin significantly affected fungal and nematode community structure and diversity but had no impact on other communities. Community impacts were more pronounced in the RNA-derived T-RFLP profiles than in the DNA-derived profiles. qPCR confirmed that azoxystrobin application significantly reduced fungal, but not bacterial, SSU rRNA gene copy number. Azoxystrobin application reduced the prevalence of ascomycete fungi, but increased the relative abundance of zygomycetes. Azoxystrobin amendment also reduced the relative abundance of nematodes in the order Enoplia, but stimulated a large increase in the relative abundance of nematodes from the order Araeolaimida. PMID:25048906

  16. The ‘Dr Jekyll and Mr Hyde fungus’: noble rot versus gray mold symptoms of Botrytis cinerea on grapes

    PubMed Central

    Fournier, Elisabeth; Gladieux, Pierre; Giraud, Tatiana

    2013-01-01

    Many cryptic species have recently been discovered in fungi, especially in fungal plant pathogens. Cryptic fungal species co-occurring in sympatry may occupy slightly different ecological niches, for example infecting the same crop plant but specialized on different organs or having different phenologies. Identifying cryptic species in fungal pathogens of crops and determining their ecological specialization are therefore crucial for disease management. Here, we addressed this question in the ascomycete Botrytis cinerea, the agent of gray mold on a wide range of plants. On grape, B. cinerea causes severe damage but is also responsible for noble rot used for processing sweet wines. We used microsatellite genotyping and clustering methods to elucidate whether isolates sampled on gray mold versus noble rot symptoms in three French regions belong to genetically differentiated populations. The inferred population structure matched geography rather than the type of symptom. Noble rot symptoms therefore do not seem to be caused by a specific B. cinerea population but instead seem to depend essentially on microclimatic conditions, which has applied consequences for the production of sweet wines. PMID:24062804

  17. Structure and composition of bacterial and fungal community in soil under soybean monoculture in the Brazilian Cerrado

    PubMed Central

    Bresolin, J.D; Bustamante, M.M.C; Krüger, R.H; Silva, M.R.S.S; Perez, K.S

    2010-01-01

    Soybean is the most important oilseed cultivated in the world and Brazil is the second major producer. Expansion of soybean cultivation has direct and indirect impacts on natural habitats of high conservation value, such as the Brazilian savannas (Cerrado). In addition to deforestation, land conversion includes the use of fertilizers and pesticides and can lead to changes in the soil microbial communities. This study evaluated the soil bacterial and fungal communities and the microbial biomass C in a native Cerrado and in a similar no-tillage soybean monoculture area using PCR-DGGE and sequencing of bands. Compared to the native area, microbial biomass C was lower in the soybean area and cluster analysis indicated that the structure of soil microbial communities differed. 16S and 18S rDNA dendrograms analysis did not show differences between row and inter-row samples, but microbial biomass C values were higher in inter-rows during soybean fructification and harvest. The study pointed to different responses and alterations in bacterial and fungal communities due to soil cover changes (fallow x growth period) and crop development. These changes might be related to differences in the pattern of root exudates affecting the soil microbial community. Among the bands chosen for sequencing there was a predominance of actinobacteria, ?-proteobacteria and ascomycetous divisions. Even under no-tillage management methods, the soil microbial community was affected due to changes in the soil cover and crop development, hence warning of the impacts caused by changes in land use. PMID:24031510

  18. Convergent targeting of a common host protein-network by pathogen effectors from three kingdoms of life

    PubMed Central

    Weßling, Ralf; Epple, Petra; Altmann, Stefan; He, Yijian; Yang, Li; Henz, Stefan R.; McDonald, Nathan; Wiley, Kristin; Bader, Kai Christian; Gläßer, Christine; Mukhtar, M. Shahid; Haigis, Sabine; Ghamsari, Lila; Stephens, Amber E.; Ecker, Joseph R.; Vidal, Marc; Jones, Jonathan D. G.; Mayer, Klaus F. X.; van Themaat, Emiel Ver Loren; Weigel, Detlef; Schulze-Lefert, Paul; Dangl, Jeffery L.; Panstruga, Ralph; Braun, Pascal

    2014-01-01

    SUMMARY While conceptual principles governing plant immunity are becoming clear, its systems-level organization and the evolutionary dynamic of the host-pathogen interface are still obscure. We generated a systematic protein-protein interaction network of virulence effectors from the ascomycete pathogen Golovinomyces orontii and Arabidopsis thaliana host proteins. We combined this dataset with corresponding data for the eubacterial pathogen Pseudomonas syringae and the oomycete pathogen Hyaloperonospora arabidopsidis. The resulting network identifies host proteins onto which intraspecies and interspecies pathogen effectors converge. Phenotyping of 124 Arabidopsis effector-interactor mutants revealed a correlation between intra- and interspecies convergence and several altered immune response phenotypes. The effectors and most heavily targeted host protein co-localized in sub-nuclear foci. Products of adaptively selected Arabidopsis genes are enriched for interactions with effector targets. Our data suggest the existence of a molecular host-pathogen interface that is conserved across Arabidopsis accessions, while evolutionary adaptation occurs in the immediate network neighborhood of effector targets. PMID:25211078

  19. Mycelial fungi in saline soils of the western Transbaikal region

    NASA Astrophysics Data System (ADS)

    Georgieva, M. L.; Lebedeva, M. P.; Bilanenko, E. N.

    2012-12-01

    Mycelial fungi in a solonchakous chestnut soil, a sulfate solonchak, and a soda solonchak were studied in the western Lake Baikal basin. The humus content, the degree of salinization, and the composition of salts affected the structure of the micromycete communities. In the chestnut soil, more than half of the species identified were found. The species diversity was higher in the nonsaline and humus horizons. The eolian deposit on the soda solonchak was characterized by the presence of six species of fungi that did not occur in other soil horizons. Their occurrence in the fresh deposit seems to be related to the eolian transfer of fungi with the fine earth from the adjacent areas with the nonsaline soils. The soda solonchak fungi are dominated by the haloalkalitolerant and alkalophilic micromycetes, among which the representatives of the Acremonium ( A. antarcticum and A. rutilum) and Verticillum genera and Mycelia sterilia were identified. There was also an alkalophilic ascomycete, which is an indicator of soda salinization— Heleococcum alkalinum. On the whole, the soda solonchak had the lowest number of fungal germs and the lowest species diversity of mycelial fungi among the soils compared.

  20. Molecular approach to characterize ectomycorrhizae fungi from Mediterranean pine stands in Portugal

    PubMed Central

    Ragonezi, Carla; Caldeira, A. Teresa; Martins, M. Rosário; Salvador, Cátia; Santos-Silva, Celeste; Ganhăo, Elsa; Klimaszewska, Krystyna; Zavattieri, Amely

    2013-01-01

    Stone pine (Pinus pinea L.), like other conifers, forms ectomycorrhizas (ECM), which have beneficial impact on plant growth in natural environments and forest ecosystems. An in vitro co-culture of stone pine microshoots with pure mycelia of isolated ECM sporocarps was used to overcome the root growth cessation not only in vitro but also to improve root development during acclimation phase. Pisolithus arhizus (Scop.) Rauschert and Lactarius deliciosus (L. ex Fr.) S.F. Gray fungi, were collected, pure cultured and used in in vitro co-culture with stone pine microshoots. Samples of P. arhizus and L. deliciosus for the in vitro co-cultures were collected from the pine stands southwest Portugal. The in situ characterization was based on their morphotypes. To confirm the identity of the collected material, ITS amplification was applied using the pure cultures derived from the sporocarps. Additionally, a molecular profile using PCR based genomic fingerprinting comparison was executed with other genera of Basidiomycetes and Ascomycetes. Our results showed the effectiveness of the techniques used to amplify DNA polymorphic sequences, which enhances the characterization of the genetic profile of ECM fungi and also provides an option to verify the fungus identity at any stage of plant mycorrhization. PMID:24294266

  1. Characterization of an antifungal soil bacterium and its antagonistic activities against Fusarium species.

    PubMed

    Chan, Yiu-Kwok; McCormick, Wayne A; Seifert, Keith A

    2003-04-01

    Bacteria were isolated from a cultivated soil and screened for antagonistic activity against Fusarium graminearum, a predominant agent of ear rot and head blight in cereal crops. Based on its in vitro effectiveness, isolate D1/2 was selected for characterization and identified as a strain of Bacillus subtilis by phenotypic tests and comparative analysis of its 16S ribosomal RNA gene (rDNA) sequence. It inhibited the mycelial growth of a collection of common fungal phytopathogens, including eight Fusarium species, three other ascomycetes, and one basidiomycete. The cell-free culture filtrate of D1/2 at different dilutions was active against macroconidium germination and hyphal growth of F. graminearum, depending on the initial macroconidium density. It induced the formation of swollen hyphal cells in liquid cultures of this fungus grown from macroconidia. A bioassay also demonstrated that D1/2 offered in planta protection against the damping-off disease in alfalfa seedlings caused by F. graminearum, while the type strain of B. subtilis was ineffective. Hence, B. subtilis D1/2 or its culture filtrate has potential application in controlling plant diseases caused by Fusarium. PMID:12897834

  2. LongSAGE gene-expression profiling of Botrytis cinerea germination suppressed by resveratrol, the major grapevine phytoalexin.

    PubMed

    Zheng, Chuanlin; Choquer, Mathias; Zhang, Bing; Ge, Hui; Hu, Songnian; Ma, Huiqin; Chen, Shangwu

    2011-09-01

    The ascomycetes Botrytis cinerea is one of the most studied necrotrophic phytopathogens and one of the main fungal parasites of grapevine. As a defense mechanism, grapevine produces a phytoalexin compound, resveratrol, which inhibits germination of the fungal conidium before it can penetrate the plant barriers and lead to host cell necrotrophy. To elucidate the effect of resveratrol on transcriptional regulation in B. cinerea germlings, two LongSAGE (long serial analysis of gene expression) libraries were generated in vitro for gene-expression profiling: 41?428 tags and among them, 15?665 unitags were obtained from resveratrol-treated B. cinerea germlings and 41?358 tags, among them, 16?362 unitags were obtained from non-treated B. cinerea germlings. In-silico analysis showed that about half of these unitags match known genes in the complete B. cinerea genome sequence. Comparison of unitag frequencies between libraries highlighted 110 genes that were transcriptionally regulated in the presence of resveratrol: 53 and 57 genes were significantly down- and upregulated, respectively. Manual curation of their putative functional categories showed that primary metabolism of germinating conidia appears to be markedly affected under resveratrol treatment, along with changes in other putative metabolic pathways, such as resveratrol detoxification and virulence-effector secretion, in B. cinerea germlings. We propose a hypothetical model of cross talk between B. cinerea germinating conidia and resveratrol-producing grapevine at the very early steps of infection. PMID:21872179

  3. Prolonged fecal shedding of 'megabacteria' (Macrorhabdus ornithogaster) by clinically healthy canaries (Serinus canaria).

    PubMed

    Lanzarot, Pilar; Blanco, Jose L; Alvarez-Perez, Sergio; Abad, Claudia; Cutuli, Maria T; Garcia, Marta E

    2013-11-01

    Macrorhabdus ornithogaster, often referred to as 'megabacterium', is an ascomycetous yeast usually found colonizing the mucosal surface of the isthmus existing between the glandular and grinding stomach of a wide diversity of bird species. However, this yeast can also behave as an avian pathogen, therefore representing a potential threat to bird breeding. The aim of this work was to assess the prevalence and patterns of fecal shedding of M. ornithogaster in a colony of healthy canary birds (Serinus canaria) bred in captivity. Fresh fecal samples from 39 canaries (17 males and 22 females) were cultured in liquid media for M. ornithogaster enrichment. Only two clinically healthy females were fecal culture-positive for the yeast, which represents an overall prevalence of 5.13% in the sampled population. A close surveillance of the two culture-positive canaries, which included periodical microscopic examination of fresh stool samples, showed prolonged fecal shedding of M. ornithogaster. Nevertheless, both animals remained asymptomatic throughout the study period. To the best of our knowledge, this is the first study reporting the continuous shedding of M. ornithogaster by clinically healthy canaries. PMID:23855411

  4. Growth and metabolic characterization of Macrorhabdus ornithogaster.

    PubMed

    Hannafusa, Yasuko; Bradley, Allison; Tomaszewski, Elizabeth E; Libal, Melissa C; Phalen, David N

    2007-05-01

    Macrorhabdus ornithogaster (M. ornithogaster) is an anamorphic ascomycetous yeast found only in the stomach of birds. Infection is often benign but has also been associated with disease in some species of birds under some circumstances. In vitro efforts to grow M. ornithogaster have been largely unsuccessful. In this report, multiple liquid and solid media of varying pH, sugar concentration, and fetal bovine serum (FBS) concentrations, incubated at various temperatures in room air or microaerophilic conditions, were examined for their ability to support the growth of M. ornithogaster, obtained from a budgerigar (Melopsittacus undulatus). Optimum growth conditions were found to be Basal Medium Eagle's, pH 3 to 4, containing 20% FBS, and 5% glucose or sucrose under microaerophilic conditions at 42 degrees C. Using these conditions, M. ornithogaster was repeatedly passaged without loss of viability. Polyclonal isolates of M. ornithogaster consistently assimilated glucose, sucrose, and trehalose. M. ornithogaster did not grow with prolonged exposure to atmospheric oxygen, but growth in microaerophilic conditions was moderately enhanced by preincubation with atmospheric oxygen for 24 hours. An isolate of M. ornithogaster was found to be infective to day-old chickens, reduce their rate of weight gain, and induce a mild to moderate heterophilic inflammation of the isthmus. M. ornithogaster was reisolated from the chicks 7 days after infection, fulfilling Koch's postulates. A 761-bp sequence of 18S rDNA from this isolate was compared to the originally reported M. ornithogaster sequence and was found to be 97% identical. PMID:17459854

  5. Mycotic proventriculitis in gray partridges (Perdix perdix) on two game bird farms.

    PubMed

    Jansson, Désirée S; Bröjer, Caroline; Mattsson, Roland; Feinstein, Ricardo; Mörner, Torsten; Hĺrd af Segerstad, Carl

    2008-09-01

    Proventriculitis and chronic respiratory disease were diagnosed in two flocks of gray partridges (Perdix perdix) on unrelated Swedish game bird farms. Affected birds showed loss of condition, respiratory signs, and flock mortality rates of 50 and 98%, respectively. The proventricular lesions were associated closely with fungal organisms that were microscopically indistinguishable from the ascomycetous yeast Macrorhabdus ornithogaster (former provisional name "megabacterium"). At necropsy, the proventriculi were swollen and hyperemic, and viscous mucus adhered to the mucosa. Proventricular hemorrhages were commonly detected, and one bird had proventricular rupture and peritonitis. Microscopically, mild to severe subacute to chronic lymphoplasmacytic proventriculitis, microabscesses, necrosis, epithelial metaplasia, disrupted koilin, ulcers, and hemorrhages were observed. Transmission electron microscopy of the proventricular microorganisms revealed a membrane-bound nucleus, vacuoles, ribosomes, microtubules in parallel arrays, and a two-layered cell wall but no mitochondria. Scanning electron microscopy of the proventricular epithelium demonstrated masses of organisms with occasional constrictions in parallel arrangement. Many of the birds also suffered from concurrent respiratory bacterial infections and/or gastrointestinal candidiasis. The clinical course and gross and microscopic proventricular lesions were similar to those described in psittacine and passerine pet birds colonized by M. ornithogaster-like microorganisms but differed from published case reports and experimental infections of chickens in which the clinical signs and lesions have been considerably milder. The findings presented in this paper suggest that mycotic proventriculitis, presumably associated with M. ornithogaster, may be a serious but possibly opportunistic, although unusual, disease problem in gray partridges on game farms. PMID:18817007

  6. An Isoprenylation and Palmitoylation Motif Promotes Intraluminal Vesicle Delivery of Proteins in Cells from Distant Species

    PubMed Central

    Oeste, Clara L.; Pinar, Mario; Schink, Kay O.; Martínez-Turrión, Javier; Stenmark, Harald; Peńalva, Miguel A.; Pérez-Sala, Dolores

    2014-01-01

    The C-terminal ends of small GTPases contain hypervariable sequences which may be posttranslationally modified by defined lipid moieties. The diverse structural motifs generated direct proteins towards specific cellular membranes or organelles. However, knowledge on the factors that determine these selective associations is limited. Here we show, using advanced microscopy, that the isoprenylation and palmitoylation motif of human RhoB (–CINCCKVL) targets chimeric proteins to intraluminal vesicles of endolysosomes in human cells, displaying preferential co-localization with components of the late endocytic pathway. Moreover, this distribution is conserved in distant species, including cells from amphibians, insects and fungi. Blocking lipidic modifications results in accumulation of CINCCKVL chimeras in the cytosol, from where they can reach endolysosomes upon release of this block. Remarkably, CINCCKVL constructs are sorted to intraluminal vesicles in a cholesterol-dependent process. In the lower species, neither the C-terminal sequence of RhoB, nor the endosomal distribution of its homologs are conserved; in spite of this, CINCCKVL constructs also reach endolysosomes in Xenopus laevis and insect cells. Strikingly, this behavior is prominent in the filamentous ascomycete fungus Aspergillus nidulans, in which GFP-CINCCKVL is sorted into endosomes and vacuoles in a lipidation-dependent manner and allows monitoring endosomal movement in live fungi. In summary, the isoprenylated and palmitoylated CINCCKVL sequence constitutes a specific structure which delineates an endolysosomal sorting strategy operative in phylogenetically diverse organisms. PMID:25207810

  7. A matter of structure: structural comparison of fungal carbonic anhydrases.

    PubMed

    Lehneck, Ronny; Pöggeler, Stefanie

    2014-10-01

    Carbonic anhydrases (CAs) are metalloenzymes that catalyze the interconversion of carbon dioxide (CO2) and hydrogen carbonate. CAs are distributed over all the three domains of life and are divided into five distinct evolutionarily unrelated gene families (?, ?, ?, ?, ?). In the large fungal kingdom, the majority of fungi encode multiple copies of ?-CAs, with some also possessing genes for ?-class CAs. Hemiascomycetous and basidiomycetous yeasts encode one or two ?-CAs, while most of the filamentous ascomycetes have multiple copies of genes encoding ?- and ?-CAs. The functions of fungal ?-CAs have been investigated intensively, while the role of fungal ?-CAs is mostly unknown. The ?-CAs are involved in sexual development, CO2-sensing, pathogenicity, and survival in ambient air. Only recently, researchers have begun to use functional and structural data of CAs from pathogenic and non-pathogenic organisms to develop powerful and effective drugs and inhibitors or to identify enzymes that can be utilized in industrial applications. Despite the large number of fungal CAs known, only five have been characterized structurally: the ?-CA AoCA of Aspergillus oryzae, the full length ?-CA Can2 from the pathogenic basidiomycete Cryptococcus neoformans, the N-terminally truncated Saccharomyces cerevisiae ?-CA Nce103, and two ?-CAs of Sordaria macrospora. This review focuses on the functional and structural properties of fungal CAs. PMID:25109265

  8. Biology and biotechnology of Trichoderma

    PubMed Central

    Schuster, André

    2010-01-01

    Fungi of the genus Trichoderma are soilborne, green-spored ascomycetes that can be found all over the world. They have been studied with respect to various characteristics and applications and are known as successful colonizers of their habitats, efficiently fighting their competitors. Once established, they launch their potent degradative machinery for decomposition of the often heterogeneous substrate at hand. Therefore, distribution and phylogeny, defense mechanisms, beneficial as well as deleterious interaction with hosts, enzyme production and secretion, sexual development, and response to environmental conditions such as nutrients and light have been studied in great detail with many species of this genus, thus rendering Trichoderma one of the best studied fungi with the genome of three species currently available. Efficient biocontrol strains of the genus are being developed as promising biological fungicides, and their weaponry for this function also includes secondary metabolites with potential applications as novel antibiotics. The cellulases produced by Trichoderma reesei, the biotechnological workhorse of the genus, are important industrial products, especially with respect to production of second generation biofuels from cellulosic waste. Genetic engineering not only led to significant improvements in industrial processes but also to intriguing insights into the biology of these fungi and is now complemented by the availability of a sexual cycle in T. reesei/Hypocrea jecorina, which significantly facilitates both industrial and basic research. This review aims to give a broad overview on the qualities and versatility of the best studied Trichoderma species and to highlight intriguing findings as well as promising applications. PMID:20461510

  9. Microbes are trophic analogs of animals

    PubMed Central

    Steffan, Shawn A.; Chikaraishi, Yoshito; Currie, Cameron R.; Horn, Heidi; Gaines-Day, Hannah R.; Pauli, Jonathan N.; Zalapa, Juan E.; Ohkouchi, Naohiko

    2015-01-01

    In most ecosystems, microbes are the dominant consumers, commandeering much of the heterotrophic biomass circulating through food webs. Characterizing functional diversity within the microbiome, therefore, is critical to understanding ecosystem functioning, particularly in an era of global biodiversity loss. Using isotopic fingerprinting, we investigated the trophic positions of a broad diversity of heterotrophic organisms. Specifically, we examined the naturally occurring stable isotopes of nitrogen (15N:14N) within amino acids extracted from proteobacteria, actinomycetes, ascomycetes, and basidiomycetes, as well as from vertebrate and invertebrate macrofauna (crustaceans, fish, insects, and mammals). Here, we report that patterns of intertrophic 15N-discrimination were remarkably similar among bacteria, fungi, and animals, which permitted unambiguous measurement of consumer trophic position, independent of phylogeny or ecosystem type. The observed similarities among bacterial, fungal, and animal consumers suggest that within a trophic hierarchy, microbiota are equivalent to, and can be interdigitated with, macrobiota. To further test the universality of this finding, we examined Neotropical fungus gardens, communities in which bacteria, fungi, and animals are entwined in an ancient, quadripartite symbiosis. We reveal that this symbiosis is a discrete four-level food chain, wherein bacteria function as the apex carnivores, animals and fungi are meso-consumers, and the sole herbivores are fungi. Together, our findings demonstrate that bacteria, fungi, and animals can be integrated within a food chain, effectively uniting the macro- and microbiome in food web ecology and facilitating greater inclusion of the microbiome in studies of functional diversity. PMID:26598691

  10. De novo generation of a phosphate starvation-regulated promoter in Candida glabrata.

    PubMed

    Kerwin, Christine L; Wykoff, Dennis D

    2012-12-01

    What steps are required for a promoter to acquire regulation by an environmental condition? We address this question by examining a promoter in Candida glabrata that is regulated by phosphate starvation and the transcription factor Pho4. The gene PMU2 encodes a secreted acid phosphatase that resulted from gene duplication events not present in other Ascomycetes, and only this gene of the three paralogs has acquired Pho4 regulation. We observe that the PMU2 promoter from C. glabrata is not functional in Saccharomyces cerevisiae, which is surprising because it is regulated by Pho4, and Pho4 is regulated in a similar manner in both species - through phosphorylation and localization. Additionally, we determine that phosphate starvation-regulated promoters in C. glabrata do not require the coactivator Pho2, which is essential to the phosphate starvation response in S. cerevisiae. We define a region of the PMU2 promoter that is important for Pho4 regulation, and this promoter region does not contain the canonical CACGTX sequence that ScPho4 utilizes for phosphate starvation-dependent transcription. However, CgPho4 utilizes CACGTX in the CgPHO84 promoter, as mutation of this sequence decreases transcription. We conclude that the acquisition of PMU2 has expanded the binding specificity of CgPho4 relative to ScPho4. PMID:22938599

  11. Origin and evolution of carnivorism in the Ascomycota (fungi).

    PubMed

    Yang, Ence; Xu, Lingling; Yang, Ying; Zhang, Xinyu; Xiang, Meichun; Wang, Chengshu; An, Zhiqiang; Liu, Xingzhong

    2012-07-01

    Carnivorism is one of the basic life strategies of fungi. Carnivorous fungi possess the ability to trap and digest their preys by sophisticated trapping devices. However, the origin and development of fungal carnivorism remains a gap in evolution biology. In this study, five protein-encoding genes were used to construct the phylogeny of the carnivorous fungi in the phylum Ascomycota; these fungi prey on nematodes by means of specialized trapping structures such as constricting rings and adhesive traps. Our analysis revealed a definitive pattern of evolutionary development for these trapping structures. Molecular clock calibration based on two fossil records revealed that fungal carnivorism diverged from saprophytism about 419 Mya, which was after the origin of nematodes about 550-600 Mya. Active carnivorism (fungi with constricting rings) and passive carnivorism (fungi with adhesive traps) diverged from each other around 246 Mya, shortly after the occurrence of the Permian-Triassic extinction event about 251.4 Mya. The major adhesive traps evolved around 198-208 Mya, which was within the time frame of the Triassic-Jurassic extinction event about 201.4 Mya. However, no major carnivorous ascomycetes divergence was correlated to the Cretaceous-Tertiary extinction event, which occurred more recently (about 65.5 Mya). Therefore, a causal relationship between mass extinction events and fungal carnivorism evolution is not validated in this study. More evidence including additional fossil records is needed to establish if fungal carnivorism evolution was a response to mass extinction events. PMID:22715289

  12. Biosynthesis and Accumulation of Ergoline Alkaloids in a Mutualistic Association between Ipomoea asarifolia (Convolvulaceae) and a Clavicipitalean Fungus1

    PubMed Central

    Markert, Anne; Steffan, Nicola; Ploss, Kerstin; Hellwig, Sabine; Steiner, Ulrike; Drewke, Christel; Li, Shu-Ming; Boland, Wilhelm; Leistner, Eckhard

    2008-01-01

    Ergoline alkaloids occur in taxonomically unrelated taxa, such as fungi, belonging to the phylum Ascomycetes and higher plants of the family Convolvulaceae. The disjointed occurrence can be explained by the observation that plant-associated epibiotic clavicipitalean fungi capable of synthesizing ergoline alkaloids colonize the adaxial leaf surface of certain Convolvulaceae plant species. The fungi are seed transmitted. Their capacity to synthesize ergoline alkaloids depends on the presence of an intact differentiated host plant (e.g. Ipomoea asarifolia or Turbina corymbosa [Convolvulaceae]). Here, we present independent proof that these fungi are equipped with genetic material responsible for ergoline alkaloid biosynthesis. The gene (dmaW) for the determinant step in ergoline alkaloid biosynthesis was shown to be part of a cluster involved in ergoline alkaloid formation. The dmaW gene was overexpressed in Saccharomyces cerevisiae, the encoded DmaW protein purified to homogeneity, and characterized. Neither the gene nor the biosynthetic capacity, however, was detectable in the intact I. asarifolia or the taxonomically related T. corymbosa host plants. Both plants, however, contained the ergoline alkaloids almost exclusively, whereas alkaloids are not detectable in the associated epibiotic fungi. This indicates that a transport system may exist translocating the alkaloids from the epibiotic fungus into the plant. The association between the fungus and the plant very likely is a symbiotum in which ergoline alkaloids play an essential role. PMID:18344419

  13. Isolation and Characterization of Sexual Spore Pigments from Aspergillus nidulans

    PubMed Central

    Brown, Daren W.; Salvo, Joseph J.

    1994-01-01

    The homothallic ascomycete Aspergillus nidulans produces two types of pigmented spores: conidia and ascospores. The synthesis and localization of the spore pigments is developmentally regulated and occurs in specialized cell types. On the basis of spectroscopic evidence, we propose that the major ascospore pigment of A. nidulans (ascoquinone A) is a novel dimeric hydroxylated anthraquinone. The structure of ascoquinone A, as well as a comparison to model compounds, suggests that it is the product of a polyketide synthase. Previous studies have revealed that the conidial pigments from A. nidulans and a related Aspergillus species (A. parasiticus) also appear to be produced via polymerization of polyketide precursors (D. W. Brown, F. M. Hauser, R. Tommasi, S. Corlett, and J. J. Salvo, Tetrahedron Lett. 34:419-422, 1993; M. E. Mayorga and W. E. Timberlake, Mol. Gen. Genet. 235:205-212, 1992). The structural similarity between the ascospore pigment and the toxic anthraquinone norsolorinic acid, the first stable intermediate in the aflatoxin pathway, suggests an evolutionary relationship between the respective polyketide synthase systems. PMID:16349224

  14. Evolution of Chemical Diversity in a Group of Non-Reduced Polyketide Gene Clusters: Using Phylogenetics to Inform the Search for Novel Fungal Natural Products

    PubMed Central

    Throckmorton, Kurt; Wiemann, Philipp; Keller, Nancy P.

    2015-01-01

    Fungal polyketides are a diverse class of natural products, or secondary metabolites (SMs), with a wide range of bioactivities often associated with toxicity. Here, we focus on a group of non-reducing polyketide synthases (NR-PKSs) in the fungal phylum Ascomycota that lack a thioesterase domain for product release, group V. Although widespread in ascomycete taxa, this group of NR-PKSs is notably absent in the mycotoxigenic genus Fusarium and, surprisingly, found in genera not known for their secondary metabolite production (e.g., the mycorrhizal genus Oidiodendron, the powdery mildew genus Blumeria, and the causative agent of white-nose syndrome in bats, Pseudogymnoascus destructans). This group of NR-PKSs, in association with the other enzymes encoded by their gene clusters, produces a variety of different chemical classes including naphthacenediones, anthraquinones, benzophenones, grisandienes, and diphenyl ethers. We discuss the modification of and transitions between these chemical classes, the requisite enzymes, and the evolution of the SM gene clusters that encode them. Integrating this information, we predict the likely products of related but uncharacterized SM clusters, and we speculate upon the utility of these classes of SMs as virulence factors or chemical defenses to various plant, animal, and insect pathogens, as well as mutualistic fungi. PMID:26378577

  15. Three-dimensional organization of three-domain copper oxidases: A review

    SciTech Connect

    Zhukhlistova, N. E. Zhukova, Yu. N.; Lyashenko, A. V.; Zaitsev, V. N.; Mikhailov, A. M.

    2008-01-15

    'Blue' copper-containing proteins are multidomain proteins that utilize a unique redox property of copper ions. Among other blue multicopper oxidases, three-domain oxidases belong to the group of proteins that exhibit a wide variety of compositions in amino acid sequences, functions, and occurrences in organisms. This paper presents a review of the data obtained from X-ray diffraction investigations of the three-dimensional structures of three-domain multicopper oxidases, such as the ascorbate oxidase catalyzing oxidation of ascorbate to dehydroascorbate and its three derivatives; the multicopper oxidase CueO (the laccase homologue); the laccases isolated from the basidiomycetes Coprinus cinereus, Trametes versicolor, Coriolus zonatus, Cerrena maxima, and Rigidoporus lignosus and the ascomycete Melanocarpus albomyces; and the bacterial laccases CotA from the endospore coats of Bacillus subtilis. A comparison of the molecular structures of the laccases of different origins demonstrates that, structurally, these objects are highly conservative. This obviously indicates that the catalytic activity of the enzymes under consideration is characterized by similar mechanisms.

  16. The Freshwater Sponge Ephydatia fluviatilis Harbours Diverse Pseudomonas Species (Gammaproteobacteria, Pseudomonadales) with Broad-Spectrum Antimicrobial Activity

    PubMed Central

    Keller-Costa, Tina; Jousset, Alexandre; van Overbeek, Leo; van Elsas, Jan Dirk; Costa, Rodrigo

    2014-01-01

    Bacteria are believed to play an important role in the fitness and biochemistry of sponges (Porifera). Pseudomonas species (Gammaproteobacteria, Pseudomonadales) are capable of colonizing a broad range of eukaryotic hosts, but knowledge of their diversity and function in freshwater invertebrates is rudimentary. We assessed the diversity, structure and antimicrobial activities of Pseudomonas spp. in the freshwater sponge Ephydatia fluviatilis. Polymerase Chain Reaction – Denaturing Gradient Gel Electrophoresis (PCR-DGGE) fingerprints of the global regulator gene gacA revealed distinct structures between sponge-associated and free-living Pseudomonas communities, unveiling previously unsuspected diversity of these assemblages in freshwater. Community structures varied across E. fluviatilis specimens, yet specific gacA phylotypes could be detected by PCR-DGGE in almost all sponge individuals sampled over two consecutive years. By means of whole-genome fingerprinting, 39 distinct genotypes were found within 90 fluorescent Pseudomonas isolates retrieved from E. fluviatilis. High frequency of in vitro antibacterial (49%), antiprotozoan (35%) and anti-oomycetal (32%) activities was found among these isolates, contrasting less-pronounced basidiomycetal (17%) and ascomycetal (8%) antagonism. Culture extracts of highly predation-resistant isolates rapidly caused complete immobility or lysis of cells of the protozoan Colpoda steinii. Isolates tentatively identified as P. jessenii, P. protegens and P. oryzihabitans showed conspicuous inhibitory traits and correspondence with dominant sponge-associated phylotypes registered by cultivation-independent analysis. Our findings suggest that E. fluviatilis hosts both transient and persistent Pseudomonas symbionts displaying antimicrobial activities of potential ecological and biotechnological value. PMID:24533086

  17. Fungal Planet description sheets: 128-153.

    PubMed

    Crous, P W; Shivas, R G; Wingfield, M J; Summerell, B A; Rossman, A Y; Alves, J L; Adams, G C; Barreto, R W; Bell, A; Coutinho, M L; Flory, S L; Gates, G; Grice, K R; Hardy, G E St J; Kleczewski, N M; Lombard, L; Longa, C M O; Louis-Seize, G; Macedo, F; Mahoney, D P; Maresi, G; Martin-Sanchez, P M; Marvanová, L; Minnis, A M; Morgado, L N; Noordeloos, M E; Phillips, A J L; Quaedvlieg, W; Ryan, P G; Saiz-Jimenez, C; Seifert, K A; Swart, W J; Tan, Y P; Tanney, J B; Thu, P Q; Videira, S I R; Walker, D M; Groenewald, J Z

    2012-12-01

    Novel species of microfungi described in the present study include the following from Australia: Catenulostroma corymbiae from Corymbia, Devriesia stirlingiae from Stirlingia, Penidiella carpentariae from Carpentaria, Phaeococcomyces eucalypti from Eucalyptus, Phialophora livistonae from Livistona, Phyllosticta aristolochiicola from Aristolochia, Clitopilus austroprunulus on sclerophyll forest litter of Eucalyptus regnans and Toxicocladosporium posoqueriae from Posoqueria. Several species are also described from South Africa, namely: Ceramothyrium podocarpi from Podocarpus, Cercospora chrysanthemoides from Chrysanthemoides, Devriesia shakazului from Aloe, Penidiella drakensbergensis from Protea, Strelitziana cliviae from Clivia and Zasmidium syzygii from Syzygium. Other species include Bipolaris microstegii from Microstegium and Synchaetomella acerina from Acer (USA), Brunneiapiospora austropalmicola from Rhopalostylis (New Zealand), Calonectria pentaseptata from Eucalyptus and Macadamia (Vietnam), Ceramothyrium melastoma from Melastoma (Indonesia), Collembolispora aristata from stream foam (Czech Republic), Devriesia imbrexigena from glazed decorative tiles (Portugal), Microcyclospora rhoicola from Rhus (Canada), Seiridium phylicae from Phylica (Tristan de Cunha, Inaccessible Island), Passalora lobeliae-fistulosis from Lobelia (Brazil) and Zymoseptoria verkleyi from Poa (The Netherlands). Valsalnicola represents a new ascomycete genus from Alnus (Austria) and Parapenidiella a new hyphomycete genus from Eucalyptus (Australia). Morphological and culture characteristics along with ITS DNA barcodes are also provided. PMID:23606771

  18. Nonribosomal peptide synthesis in Schizosaccharomyces pombe and the architectures of ferrichrome-type siderophore synthetases in fungi.

    PubMed

    Schwecke, Torsten; Göttling, Kirsten; Durek, Pawel; Dueńas, Ines; Käufer, Norbert F; Zock-Emmenthal, Susanne; Staub, Eike; Neuhof, Torsten; Dieckmann, Ralf; von Döhren, Hans

    2006-04-01

    A nonribosomal peptide synthetase (NRPS) in Schizosaccharomyces pombe, which possesses an unusual structure incorporating three adenylation domains, six thiolation domains and six condensation domains, has been shown to produce the cyclohexapeptide siderophore ferrichrome. One of the adenylation domains is truncated and contains a distorted key motif. Substrate-binding specificities of the remaining two domains were assigned by molecular modelling to glycine and to N-acetyl-N-hydroxy-L-ornithine. Hexapeptide siderophore synthetase genes of Magnaporthe grisea and Fusarium graminearum were both identified and analyzed with respect to substrate-binding sites, and the predicted product ferricrocin was identified in each. A comparative analysis of these synthetase systems, including those of the basidiomycete Ustilago maydis, the homobasidiomycete Omphalotus olearius and the ascomycetes Aspergillus nidulans, Aspergillus fumigatus, Fusarium graminearum, Cochliobolus heterostrophus, Neurospora crassa and Aureobasidium pullulans, revealed divergent domain compositions with respect to their number and positioning, although all produce similar products by iterative processes. A phylogenetic analysis of both NRPSs and associated L-N5-ornithine monooxygenases revealed that ferrichrome-type siderophore biosynthesis has coevolved in fungi with varying in trans interactions of NRPS domains. PMID:16502473

  19. Furocoumarins and coumarins photoinactivate Colletotrichum acutatum and Aspergillus nidulans fungi under solar radiation.

    PubMed

    de Menezes, Henrique D; Pereira, Ana C; Brancini, Guilherme T P; de Leăo, Helton Carlos; Massola Júnior, Nelson S; Bachmann, Luciano; Wainwright, Mark; Bastos, Jairo Kenupp; Braga, Gilberto U L

    2014-02-01

    The increasing tolerance to currently-used fungicides is a major problem both in clinical and agricultural areas leading to an urgent need for the development of novel antifungal strategies. This study investigated the in vitro antimicrobial photo treatment (APT) of conidia of the plant-pathogenic fungus Colletotrichum acutatum and the ascomycete Aspergillus nidulans with the furocoumarins 8-methoxypsoralen (8-MOP) and isopimpinellin, and a mixture of two coumarins (7-methoxy coumarin and citropten). Subcellular localization of the photosensitizer 8-MOP was also determined in C. acutatum conidia. Additionally, the effects of APT on the leaves of the plant host Citrus sinensis were determined. APT with 8-MOP (50?M) led to a reduction of approximately 4 logs in the survival of the conidia of both species, and the mixture of the two coumarins (12.5mgL(-1)) resulted in a reduction of approximately 4 logs for A. nidulans and 3 logs for C. acutatum. Isopimpinellin (50?M) displayed a reduction of 4 logs for A. nidulans but less than 2 logs for C. acutatum. Washing the conidia to remove unbound photosensitizers before light exposure reduced the photodynamic inactivation of C. acutatum both with 8-MOP and the mixture of the two coumarins. The reduction was smaller for A. nidulans. 8-MOP spread throughout the cytoplasm and accumulated in structures such as lipid bodies of C. acutatum conidia. No damage to orange tree leaves was observed after APT with any of the photosensitizers. PMID:24509069

  20. Phylogenetic reconstruction of endophytic fungal isolates using internal transcribed spacer 2 (ITS2) region

    PubMed Central

    GokulRaj, Kathamuthu; Sundaresan, Natesan; Ganeshan, Enthai Jagan; Rajapriya, Pandi; Muthumary, Johnpaul; Sridhar, Jayavel; Pandi, Mohan

    2014-01-01

    Endophytic fungi are inhabitants of plants, living most part of their lifecycle asymptomatically which mainly confer protection and ecological advantages to the host plant. In this present study, 48 endophytic fungi were isolated from the leaves of three medicinal plants and characterized based on ITS2 sequence – secondary structure analysis. ITS2 secondary structures were elucidated with minimum free energy method (MFOLD version 3.1) and consensus structure of each genus was generated by 4SALE. ProfDistS was used to generate ITS2 sequence structure based phylogenetic tree respectively. Our elucidated isolates were belonging to Ascomycetes family, representing 5 orders and 6 genera. Colletotrichum/Glomerella spp., Diaporthae/Phomopsis spp., and Alternaria spp., were predominantly observed while Cochliobolus sp., Cladosporium sp., and Emericella sp., were represented by singletons. The constructed phylogenetic tree has well resolved monophyletic groups with >50% bootstrap value support. Secondary structures based fungal systematics improves not only the stability; it also increases the precision of phylogenetic inference. Above ITS2 based phylogenetic analysis was performed for our 48 isolates along with sequences of known ex-types taken from GenBank which confirms the efficiency of the proposed method. Further, we propose it as superlative marker for reconstructing phylogenetic relationships at different taxonomic levels due to their lesser length. PMID:25097373

  1. Carbon sequestration is related to mycorrhizal fungal community shifts during long-term succession in boreal forests.

    PubMed

    Clemmensen, Karina E; Finlay, Roger D; Dahlberg, Anders; Stenlid, Jan; Wardle, David A; Lindahl, Björn D

    2015-03-01

    Boreal forest soils store a major proportion of the global terrestrial carbon (C) and below-ground inputs contribute as much as above-ground plant litter to the total C stored in the soil. A better understanding of the dynamics and drivers of root-associated fungal communities is essential to predict long-term soil C storage and climate feedbacks in northern ecosystems. We used 454-pyrosequencing to identify fungal communities across fine-scaled soil profiles in a 5000 yr fire-driven boreal forest chronosequence, with the aim of pinpointing shifts in fungal community composition that may underlie variation in below-ground C sequestration. In early successional-stage forests, higher abundance of cord-forming ectomycorrhizal fungi (such as Cortinarius and Suillus species) was linked to rapid turnover of mycelial biomass and necromass, efficient nitrogen (N) mobilization and low C sequestration. In late successional-stage forests, cord formers declined, while ericoid mycorrhizal ascomycetes continued to dominate, potentially facilitating long-term humus build-up through production of melanized hyphae that resist decomposition. Our results suggest that cord-forming ectomycorrhizal fungi and ericoid mycorrhizal fungi play opposing roles in below-ground C storage. We postulate that, by affecting turnover and decomposition of fungal tissues, mycorrhizal fungal identity and growth form are critical determinants of C and N sequestration in boreal forests. PMID:25494880

  2. Specificity and transmission mosaic of ant nest-wall fungi

    PubMed Central

    Schlick-Steiner, Birgit C.; Steiner, Florian M.; Konrad, Heino; Seifert, Bernhard; Christian, Erhard; Moder, Karl; Stauffer, Christian; Crozier, Ross H.

    2008-01-01

    Mutualism, whereby species interact to their mutual benefit, is extraordinary in a competitive world. To recognize general patterns of origin and maintenance from the plethora of mutualistic associations proves a persisting challenge. The simplest situation is believed to be that of a single mutualist specific to a single host, vertically transmitted from one host generation to the next. We characterized ascomycete fungal associates cultured for nest architecture by the ant subgenera Dendrolasius and Chthonolasius. The ants probably manage their fungal mutualists by protecting them against fungal competitors. The ant subgenera display different ant-to-fungus specificity patterns, one-to-two and many-to-one, and we infer vertical transmission, in the latter case overlaid by horizontal transmission. Possible evolutionary trajectories include a reversal from fungiculture by other Lasius subgenera and inheritance of fungi through life cycle interactions of the ant subgenera. The mosaic indicates how specificity patterns can be shaped by an interplay between host life-cycles and transmission adaptations. PMID:18195358

  3. The interrelationship of mycophagous small mammals and ectomycorrhizal fungi in primeval, disturbed and managed Central European mountainous forests.

    PubMed

    Schickmann, Susanne; Urban, Alexander; Kräutler, Katharina; Nopp-Mayr, Ursula; Hackländer, Klaus

    2012-10-01

    Small forest dwelling mammals are considered to be major consumers and vectors of hypogeous ectomycorrhizal (ECM) fungi, which have lost the ability of active spore discharge. Fungal spore dispersal by mycophagy is deemed an important process involved in forest regeneration, resilience and vitality, primarily based on evidence from Australia and the Pacific Northwestern USA, but is poorly known for Central European mountainous forests thus far. Small mammal mycophagy was investigated by live trapping and microscopical analysis of faecal samples. All small mammal species recorded (Myodes glareolus, Microtus agrestis, Pitymys subterraneus, Apodemus spp., Glis glis, Sorex spp.) had ingested spores of ECM fungi, albeit in varying amounts. My. glareolus was found to be the most important vector of ECM fungal spores, both in quantity and diversity. Species of the genus Sorex seem to play a hitherto underestimated role as dispersers of fungal spores. Glis glis is likely to be an important vector owing to its large home range. Hypogeous ECM basidiomycetes accounted for most spores found in the faecal samples. The frequency of various genera of hypogeous ECM ascomycetes and ECM epigeous fungi was much lower. Comparison with null models indicated a non-random structure of the mycophagy network similar to other mutualistic bipartite networks. Mycophagy can be considered (1) to contribute to nutrition of small forest mammals, (2) to play a pivotal role for forest regeneration and functioning by providing mycorrhizal inoculum to tree seedlings and (3) to be vital for reproduction and diversity of the still poorly known hypogeous fungi. PMID:22466900

  4. Production of Obionin A and Derivatives by the Sooty Blotch Fungus Microcyclospora malicola.

    PubMed

    Surup, Frank; Medjedovi?, Ajda; Schroers, Hans-Josef; Stadler, Marc

    2015-10-01

    A multitude of sooty blotch and flyspeck fungi, mainly belonging to the Ascomycetes order Capnodiales, causes dark blemishes and flyspeck-like spots on apples worldwide. Different sooty blotch and flyspeck fungi can coexist in the same orchard and even on a single fruit. Our preceding experiments revealed an activity of Microcyclospora malicola strain 1930 against the anthracnose fungus Colletotrichum fioriniae in dual culture assays. Extracts of M. malicola strain 1930 showed a broad bioactivity against filamentous fungus Mucor hiemalis and gram-positive bacterium Bacillus subtilis. A bioactivity-guided isolation led to the identification of obionin A (1) as the main active principle. In addition to 1, which was previously isolated from the marine fungus Leptosphaeria obiones, we isolated three derivatives. Metabolite 2 bears a keto function at C-6, besides the replacement of oxygen by nitrogen at position 10. Two more derivatives are adducts (3, 4) of acetone as work-up artifacts. Because obionin A (1) and its derivative 2 showed cytotoxic effects and antifungal activities, we propose a role of these secondary metabolites in the antagonism between M. malicola and other apple colonizing sooty blotch and flyspeck fungi, other epiphytes, or apple pathogens competing for the same ecological niche. PMID:25856439

  5. The Oxygenase CAO-1 of Neurospora crassa Is a Resveratrol Cleavage Enzyme

    PubMed Central

    Díaz-Sánchez, Violeta; F. Estrada, Alejandro; Limón, M. Carmen; Al-Babili, Salim

    2013-01-01

    The genome of the ascomycete Neurospora crassa encodes CAO-1 and CAO-2, two members of the carotenoid cleavage oxygenase family that target double bonds in different substrates. Previous studies demonstrated the role of CAO-2 in cleaving the C40 carotene torulene, a key step in the synthesis of the C35 apocarotenoid pigment neurosporaxanthin. In this work, we investigated the activity of CAO-1, assuming that it may provide retinal, the chromophore of the NOP-1 rhodopsin, by cleaving ?-carotene. For this purpose, we tested CAO-1 activity with carotenoid substrates that were, however, not converted. In contrast and consistent with its sequence similarity to family members that act on stilbenes, CAO-1 cleaved the interphenyl C?-C? double bond of resveratrol and its derivative piceatannol. CAO-1 did not convert five other similar stilbenes, indicating a requirement for a minimal number of unmodified hydroxyl groups in the stilbene background. Confirming its biological function in converting stilbenes, adding resveratrol led to a pronounced increase in cao-1 mRNA levels, while light, a key regulator of carotenoid metabolism, did not alter them. Targeted ?cao-1 mutants were not impaired by the presence of resveratrol, a phytoalexin active against different fungi, which did not significantly affect the growth and development of wild-type Neurospora. However, under partial sorbose toxicity, the ?cao-1 colonies exhibited faster radial growth than control strains in the presence of resveratrol, suggesting a moderate toxic effect of resveratrol cleavage products. PMID:23893079

  6. The oxygenase CAO-1 of Neurospora crassa is a resveratrol cleavage enzyme.

    PubMed

    Díaz-Sánchez, Violeta; Estrada, Alejandro F; Limón, M Carmen; Al-Babili, Salim; Avalos, Javier

    2013-09-01

    The genome of the ascomycete Neurospora crassa encodes CAO-1 and CAO-2, two members of the carotenoid cleavage oxygenase family that target double bonds in different substrates. Previous studies demonstrated the role of CAO-2 in cleaving the C40 carotene torulene, a key step in the synthesis of the C35 apocarotenoid pigment neurosporaxanthin. In this work, we investigated the activity of CAO-1, assuming that it may provide retinal, the chromophore of the NOP-1 rhodopsin, by cleaving ?-carotene. For this purpose, we tested CAO-1 activity with carotenoid substrates that were, however, not converted. In contrast and consistent with its sequence similarity to family members that act on stilbenes, CAO-1 cleaved the interphenyl C?-C? double bond of resveratrol and its derivative piceatannol. CAO-1 did not convert five other similar stilbenes, indicating a requirement for a minimal number of unmodified hydroxyl groups in the stilbene background. Confirming its biological function in converting stilbenes, adding resveratrol led to a pronounced increase in cao-1 mRNA levels, while light, a key regulator of carotenoid metabolism, did not alter them. Targeted ?cao-1 mutants were not impaired by the presence of resveratrol, a phytoalexin active against different fungi, which did not significantly affect the growth and development of wild-type Neurospora. However, under partial sorbose toxicity, the ?cao-1 colonies exhibited faster radial growth than control strains in the presence of resveratrol, suggesting a moderate toxic effect of resveratrol cleavage products. PMID:23893079

  7. Genes for parasite-specific, nonhost resistance in populus.

    PubMed

    Newcombe, George

    2005-07-01

    ABSTRACT Nonhost resistance is hypothesized to protect plants in a nonspecific manner. For highly specialized parasites, this hypothesis applies not only to distantly related plants but also to resistant congeners of the host species. Congeners of Populus spp. were hybridized to create two interspecific hybrid poplar pedigrees (i.e., Populus trichocarpa x P. deltoides and P. trichocarpa x P. maximowiczii). The pedigrees were planted in a randomized, replicated "common garden" on Vancouver Island so that they were exposed to parasites of the native P. trichocarpa. Monogenic and oligogenic resistance to two ascomycetous, parasitic fungi (i.e., Venturia inopina and a Taphrina sp.) segregated in a parasite-specific manner in each pedigree. However, these resistance genes were not inherited from the native host, P. trichocarpa. Instead, resistance was inherited from the allopatric, nonhost congeners, P. deltoides (eastern cottonwood) and P. maximowiczii (Japanese poplar). Thus, we found that major genes condition parasite-specific, nonhost resistance, as has been true in earlier studies of this kind with additional parasites of Populus spp. The selective force responsible for evolutionary maintenance of such genes is unknown. PMID:18943010

  8. Early diverging Ascomycota: phylogenetic divergence and related evolutionary enigmas.

    PubMed

    Sugiyama, Junta; Hosaka, Kentaro; Suh, Sung-Oui

    2006-01-01

    The early diverging Ascomycota lineage, detected primarily from nSSU rDNA sequence-based phylogenetic analyses, includes enigmatic key taxa important to an understanding of the phylogeny and evolution of higher fungi. At the moment six representative genera of early diverging ascomycetes (i.e. Taphrina, Protomyces, Saitoella, Schizosaccharomyces, Pneumocystis and Neolecta) have been assigned to "Archiascomycetes" sensu Nishida and Sugi ama (1994) or the subphylum "Taphrinomycotina" sensu Eriksson and Winka (1997). The group includes fungi that are ecologically and morphologically diverse, and it is difficult therefore to define the group based on common phenotypic characters. Bayesian analyses of nSSU rDNA or combined nSSU and nLSU rDNA sequences supported previously published Ascomycota frameworks that consist of three major lineages (i.e. a group of early diverging Ascomycota. [Taphrinomycotina], Saccharomycotina and Pezizomycotina); Taphrinomycotina is the sister group of Saccharomycotina and Pezizomycotina. The 50% majority rule consensus of 18000 Bayesian MCMCMC-generated trees from multilocus gene sequences of nSSU rDNA, nLSU rDNA (D1/D2), RPB2 and beta-tubulin also showed the monophyly of the three subphyla and the basal position of Taphrinomycotina in Ascomycota with significantly higher statistical support. However to answer controversial questions on the origin, monophyly and evolution of the Taphrinomycotina, additional integrated phylogenetic analyses might be necessary using sequences of more genes with broader taxon sampling from the early diverging Ascomycota. PMID:17486975

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

    PubMed Central

    Spatafora, J W; Mitchell, T G; Vilgalys, R

    1995-01-01

    Because of their ability to display yeast-like growth forms in various environmental conditions, dematiaceous (melanized) hyphomycetes of the form-genera Exophiala, Rhinocladiella, and Wangiella have been informally termed "black yeasts." Cladistic analysis of 1,050 bp of the genes coding for small-subunit rRNA (SSU rDNA) supported a close relationship among species of these black yeasts with other dematiaceous hyphomycetes in the form-genera Fonsecaea, Phialophora, and Ramichloridium. The conventional categories of these fungi based on asexual states are not supported by phylogenetic analysis of SSU rDNA sequences. Isolates exhibiting annellidic modes of blastic conidiogenesis (e.g., Exophiala spp.) were not monophyletic and were placed as sister taxa to isolates that produce phialides or sympodulae. The results indicated very close relationships between isolates of Wangiella dermatitidis and Exophiala mansonii and between Rhinocladiella aquaspersa and Exophiala jeanselmei. This clade of dematiaceous hyphomycetes was a sister group to a clade comprising members of two orders of cleistothecial ascomycetes, Eurotiales and Onygenales. The etiological agents of chromoblastomycosis were found to be a closely related group (clade), while the agents of phaeohyphomycosis displayed a broader distribution on the SSU rDNA tree. PMID:7615749

  10. Ultrastructure of mitosis in the cowpea rust fungus Uromyces phaseoli var. Vignae

    PubMed Central

    1976-01-01

    Aspects of the ultrastructure of mitotic nuclei of the fungus Uromyces phaseoli var. vignae are described from both intercellular hyphae in the cowpea host and infection structures induced to differentiate in vitro. The interphase nucleus-associated organelle (NAO) consists of two trilamellar acircular disks connceted by an osmiophilic bar. The intranuclear spindle develops between these disks when they separate. The spindle contains pole to pole, interdigitating, chromosomal, and fragmentary microtubules arranged to form a central bundle along the surface of which lie the metaphase chromosomes. No metaphase plate is found. There are up to three microtubules per kinetochore and approximately 14 chromosomes on the haploid spindle. Telophase elongation appears to involve extension of pole to pole microtubules with no evidence for the remaining presence of interdigitating microtubules. Concomitantly, numerous cytoplasmic microtubules develop from each NAO disk where few or none are present in other phases. Reformation of the interphase NAO involves the formation of a sausage- shaped intermediate at late telophase. The nuclear envelope remains intact and the nucleolus persists throughtout division. Various aspects of the spindle and NAOs appear to be evolutionary intermediates between Ascomycetes and higher Basidiomycetes, thus supporting the theory of Basidiomycete evolution from the former group and demonstrating an encouraging correlation between mitotic characteristics and other phylogenetic markers. PMID:956269

  11. In Situ Accessibility of Saccharomyces cerevisiae 26S rRNA to Cy3-Labeled Oligonucleotide Probes Comprising the D1 and D2 Domains

    PubMed Central

    Inácio, Joăo; Behrens, Sebastian; Fuchs, Bernhard M.; Fonseca, Álvaro; Spencer-Martins, Isabel; Amann, Rudolf

    2003-01-01

    Fluorescence in situ hybridization (FISH) has proven to be most useful for the identification of microorganisms. However, species-specific oligonucleotide probes often fail to give satisfactory results. Among the causes leading to low hybridization signals is the reduced accessibility of the targeted rRNA site to the oligonucleotide, mainly for structural reasons. In this study we used flow cytometry to determine whole-cell fluorescence intensities with a set of 32 Cy3-labeled oligonucleotide probes covering the full length of the D1 and D2 domains in the 26S rRNA of Saccharomyces cerevisiae PYCC 4455T. The brightest signal was obtained with a probe complementary to positions 223 to 240. Almost half of the probes conferred a fluorescence intensity above 60% of the maximum, whereas only one probe could hardly detect the cells. The accessibility map based on the results obtained can be extrapolated to other yeasts, as shown experimentally with 27 additional species (14 ascomycetes and 13 basidiomycetes). This work contributes to a more rational design of species-specific probes for yeast identification and monitoring. PMID:12732564

  12. Phylogenomic analyses support the monophyly of Taphrinomycotina, including Schizosaccharomyces fission yeasts.

    PubMed

    Liu, Yu; Leigh, Jessica W; Brinkmann, Henner; Cushion, Melanie T; Rodriguez-Ezpeleta, Naiara; Philippe, Hervé; Lang, B Franz

    2009-01-01

    Several morphologically dissimilar ascomycete fungi including Schizosaccharomyces, Taphrina, Saitoella, Pneumocystis, and Neolecta have been grouped into the taxon Taphrinomycotina (Archiascomycota or Archiascomycotina), originally based on rRNA phylogeny. These analyses lack statistically significant support for the monophyly of this grouping, and although confirmed by more recent multigene analyses, this topology is contradicted by mitochondrial phylogenies. To resolve this inconsistency, we have assembled phylogenomic mitochondrial and nuclear data sets from four distantly related taphrinomycotina taxa: Schizosaccharomyces pombe, Pneumocystis carinii, Saitoella complicata, and Taphrina deformans. Our phylogenomic analyses based on nuclear data (113 proteins) conclusively support the monophyly of Taphrinomycotina, diverging as a sister group to Saccharomycotina + Pezizomycotina. However, despite the improved taxon sampling, Taphrinomycotina continue to be paraphyletic with the mitochondrial data set (13 proteins): Schizosaccharomyces species associate with budding yeasts (Saccharomycotina) and the other Taphrinomycotina group as a sister group to Saccharomycotina + Pezizomycotina. Yet, as Schizosaccharomyces and Saccharomycotina species are fast evolving, the mitochondrial phylogeny may be influenced by a long-branch attraction (LBA) artifact. After removal of fast-evolving sequence positions from the mitochondrial data set, we recover the monophyly of Taphrinomycotina. Our combined results suggest that Taphrinomycotina is a legitimate taxon, that this group of species diverges as a sister group to Saccharomycotina + Pezizomycotina, and that phylogenetic positioning of yeasts and fission yeasts with mitochondrial data is plagued by a strong LBA artifact. PMID:18922765

  13. Genome Sequencing of the Plant Pathogen Taphrina deformans, the Causal Agent of Peach Leaf Curl

    PubMed Central

    Cissé, Ousmane H.; Almeida, Joăo M. G. C. F.; Fonseca, Álvaro; Kumar, Ajay Anand; Salojärvi, Jarkko; Overmyer, Kirk; Hauser, Philippe M.; Pagni, Marco

    2013-01-01

    ABSTRACT Taphrina deformans is a fungus responsible for peach leaf curl, an important plant disease. It is phylogenetically assigned to the Taphrinomycotina subphylum, which includes the fission yeast and the mammalian pathogens of the genus Pneumocystis. We describe here the genome of T. deformans in the light of its dual plant-saprophytic/plant-parasitic lifestyle. The 13.3-Mb genome contains few identifiable repeated elements (ca. 1.5%) and a relatively high GC content (49.5%). A total of 5,735 protein-coding genes were identified, among which 83% share similarities with other fungi. Adaptation to the plant host seems reflected in the genome, since the genome carries genes involved in plant cell wall degradation (e.g., cellulases and cutinases), secondary metabolism, the hallmark glyoxylate cycle, detoxification, and sterol biosynthesis, as well as genes involved in the biosynthesis of plant hormones. Genes involved in lipid metabolism may play a role in its virulence. Several locus candidates for putative MAT cassettes and sex-related genes akin to those of Schizosaccharomyces pombe were identified. A mating-type-switching mechanism similar to that found in ascomycetous yeasts could be in effect. Taken together, the findings are consistent with the alternate saprophytic and parasitic-pathogenic lifestyles of T. deformans. PMID:23631913

  14. Comparative Evolutionary Histories of the Fungal Chitinase Gene Family Reveal Non-Random Size Expansions and Contractions due to Adaptive Natural Selection

    PubMed Central

    Karlsson, Magnus; Stenlid, Jan

    2008-01-01

    Gene duplication and loss play an important role in the evolution of novel functions and for shaping an organism’s gene content. Recently, it was suggested that stress-related genes frequently are exposed to duplications and losses, while growth-related genes show selection against change in copy number. The fungal chitinase gene family constitutes an interesting case study of gene duplication and loss, as their biological roles include growth and development as well as more stress-responsive functions. We used genome sequence data to analyze the size of the chitinase gene family in different fungal taxa, which range from 1 in Batrachochytrium dendrobatidis and Schizosaccharomyces pombe to 20 in Hypocrea jecorina and Emericella nidulans, and to infer their phylogenetic relationships. Novel chitinase subgroups are identified and their phylogenetic relationships with previously known chitinases are discussed. We also employ a stochastic birth and death model to show that the fungal chitinase gene family indeed evolves non-randomly, and we identify six fungal lineages where larger-than-expected expansions (Pezizomycotina, H. jecorina, Gibberella zeae, Uncinocarpus reesii, E. nidulans and Rhizopus oryzae), and two contractions (Coccidioides immitis and S. pombe) potentially indicate the action of adaptive natural selection. The results indicate that antagonistic fungal-fungal interactions are an important process for soil borne ascomycetes, but not for fungal species that are pathogenic in humans. Unicellular growth is correlated with a reduction of chitinase gene copy numbers which emphasizes the requirement of the combined action of several chitinases for filamentous growth. PMID:19204807

  15. Exploring micromycetes biodiversity for screening benzo[a]pyrene degrading potential.

    PubMed

    Rafin, Catherine; de Foucault, Bruno; Veignie, Etienne

    2013-05-01

    Twenty-five strains of filamentous fungi, encompassing 14 different species and belonging mainly to Ascomycetes, were tested for their ability to degrade benzo[a]pyrene (BaP) in mineral liquid medium. The most performing isolates for BaP degradation (200 mg l(-1)) in mineral medium were Cladosporium sphaerospermum with 29 % BaP degradation, i.e., 82.8 ?g BaP degraded per day (day(-1)), Paecilomyces lilacinus with 20.5 % BaP degradation, i.e., 58.5 ?g BaP day(-1), and Verticillium insectorum with 22.3 % BaP degradation, i.e., 64.3 ?g BaP day(-1), after only 7 days of incubation. Four variables, e.g., biomass growth on hexadecane and glucose, BaP solubilization, activities of extracellular- and mycelium-associated peroxidase, and polyethylene glycol degradation, were also studied as selective criteria presumed to be involved in BaP degradation. Among these variables, the tests based on polyethylene glycol degradation and on fungal growth on hexadecane and glucose seemed to be the both pertinent criteria for setting apart isolates competent in BaP degradation, suggesting the occurrence of different mechanisms presumed to be involved in pollutant degradation among the studied micromycetes. PMID:23093417

  16. Cellulolytic potential of thermophilic species from four fungal orders

    PubMed Central

    2013-01-01

    Elucidation of fungal biomass degradation is important for understanding the turnover of biological materials in nature and has important implications for industrial biomass conversion. In recent years there has been an increasing interest in elucidating the biological role of thermophilic fungi and in characterization of their industrially useful enzymes. In the present study we investigated the cellulolytic potential of 16 thermophilic fungi from the three ascomycete orders Sordariales, Eurotiales and Onygenales and from the zygomycete order Mucorales thus covering all fungal orders that include thermophiles. Thermophilic fungi are the only described eukaryotes that can grow at temperatures above 45°C. All 16 fungi were able to grow on crystalline cellulose but their secreted enzymes showed widely different cellulolytic activities, pH optima and thermostabilities. Interestingly, in contrast to previous reports, we found that some fungi such as Melanocarpus albomyces readily grew on crystalline cellulose and produced cellulases. These results indicate that there are large differences in the cellulolytic potential of different isolates of the same species. Furthermore, all the selected species were able to degrade cellulose but the differences in cellulolytic potential and thermostability of the secretome did not correlate to the taxonomic position. PCR amplification and sequencing of 22 cellulase genes from the fungi showed that the level of thermostability of the cellulose-degrading activity could not be inferred from the phylogenetic relationship of the cellulases. PMID:23958135

  17. Sour rot-damaged grapes are sources of wine spoilage yeasts.

    PubMed

    Barata, André; González, Sara; Malfeito-Ferreira, Manuel; Querol, Amparo; Loureiro, Virgílio

    2008-11-01

    Yeast species of sound and sour rot-damaged grapes were analysed during fermentation and grape ripening in the vineyard, using general and selective culture media. During 2003 and 2004 vintages, microvinifications were carried out with sound grapes to which different amounts of grapes with sour rot were added. The wine spoilage species Zygosaccharomyces bailii was only recovered during fermentations with sour rot, reaching 5.00 log CFU mL(-1) (2003) and 2.48 log CFU mL(-1) (2004) at the end of fermentation. The study of yeast populations during the sour rot ripening process (2005 vintage) showed that the veraison-damaged grapes always exhibited higher total yeast counts and a much greater diversity of species. From a total of 22 ascomycetous species, 17 were present only in damaged grapes. The most frequent species were Issatchenkia occidentalis and Zygoascus hellenicus. The spoilage species Z. bailii and Zygosaccharomyces bisporus were consistently isolated exclusively from damaged grapes. This work demonstrates that one of the most dangerous wine spoilage species, Z. bailii, is strongly associated with sour rot grapes and survives during fermentation with Saccharomyces cerevisiae. The use of selective media provides a more accurate characterization of grape contamination species. PMID:18554306

  18. Phylogenetic Relationships Matter: Antifungal Susceptibility among Clinically Relevant Yeasts

    PubMed Central

    Schmalreck, A. F.; Becker, K.; Fegeler, W.; Czaika, V.; Ulmer, H.; Lass-Flörl, C.

    2014-01-01

    The objective of this study was 2-fold: to evaluate whether phylogenetically closely related yeasts share common antifungal susceptibility profiles (ASPs) and whether these ASPs can be predicted from phylogeny. To address this question, 9,627 yeast strains were collected and tested for their antifungal susceptibility. Isolates were reidentified by considering recent changes in taxonomy and nomenclature. A phylogenetic (PHYLO) code based on the results of multilocus sequence analyses (large-subunit rRNA, small-subunit rRNA, translation elongation factor 1?, RNA polymerase II subunits 1 and 2) and the classification of the cellular neutral sugar composition of coenzyme Q and 18S ribosomal DNA was created to group related yeasts into PHYLO groups. The ASPs were determined for fluconazole, itraconazole, and voriconazole in each PHYLO group. The majority (95%) of the yeast strains were Ascomycetes. After reclassification, a total of 23 genera and 54 species were identified, resulting in an increase of 64% of genera and a decrease of 5% of species compared with the initial identification. These taxa were assigned to 17 distinct PHYLO groups (Ascomycota, n = 13; Basidiomycota, n = 4). ASPs for azoles were similar among members of the same PHYLO group and different between the various PHYLO groups. Yeast phylogeny may be an additional tool to significantly enhance the assessment of MIC values and to predict antifungal susceptibility, thereby more rapidly initiating appropriate patient management. PMID:24366735

  19. Identification of Medically Relevant Species of Arthroconidial Yeasts by Use of Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry

    PubMed Central

    Kolecka, Anna; Khayhan, Kantarawee; Groenewald, Marizeth; Theelen, Bart; Arabatzis, Michael; Velegraki, Aristea; Kostrzewa, Markus; Mares, Mihai; Taj-Aldeen, Saad J.

    2013-01-01

    Matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) was used for an extensive identification study of arthroconidial yeasts, using 85 reference strains from the CBS-KNAW yeast collection and 134 clinical isolates collected from medical centers in Qatar, Greece, and Romania. The test set included 72 strains of ascomycetous yeasts (Galactomyces, Geotrichum, Saprochaete, and Magnusiomyces spp.) and 147 strains of basidiomycetous yeasts (Trichosporon and Guehomyces spp.). With minimal preparation time, MALDI-TOF MS proved to be an excellent diagnostic tool that provided reliable identification of most (98%) of the tested strains to the species level, with good discriminatory power. The majority of strains were correctly identified at the species level with good scores (>2.0) and seven of the tested strains with log score values between 1.7 and 2.0. The MALDI-TOF MS results obtained were consistent with validated internal transcribed spacer (ITS) and/or large subunit (LSU) ribosomal DNA sequencing results. Expanding the mass spectrum database by increasing the number of reference strains for closely related species, including those of nonclinical origin, should enhance the usefulness of MALDI-TOF MS-based diagnostic analysis of these arthroconidial fungi in medical and other laboratories. PMID:23678074

  20. Agrobacterium tumefaciens-mediated transformation of Leptosphaeria spp. and Oculimacula spp. with the reef coral gene DsRed and the jellyfish gene gfp.

    PubMed

    Eckert, Maria; Maguire, Kerry; Urban, Martin; Foster, Simon; Fitt, Bruce; Lucas, John; Hammond-Kosack, Kim

    2005-12-01

    Four filamentous ascomycetes, Leptosphaeria maculans, L. biglobosa, Oculimacula yallundae and O. acuformis, were transformed via Agrobacterium tumefaciens-mediated transformation with the genes encoding DsRed and GFP. Using vectors pCAMDsRed and pCAMBgfp, either germinated conidia of Leptosphaeria spp. and O. yallundae or physically fragmented cultures of Oculimacula spp. were transformed. In vitro, the expression of the two reporter proteins in mycelium of both Oculimacula and both Leptosphaeria species was sufficient to distinguish each species in co-inoculated cultures. In planta, transformants of L. maculans or L. biglobosa expressing DsRed or GFP could be observed together in leaves of Brassica napus. Either reporter protein could be used to view the colonization of leaf petioles by both Leptosphaeria spp. and growth in the xylem vessels could be clearly observed. With the generation of these transformants, further studies on interactions between pathogen species involved in disease complexes on various host species and between opposite mating types of the same species are now possible. PMID:16243451