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Sample records for ascomycete podospora anserina

  1. Genetic control of anastomosis in Podospora anserina.

    PubMed

    Tong, Laetitia Chan Ho; Silar, Philippe; Lalucque, Hervé

    2014-09-01

    We developed a new microscopy procedure to study anastomoses in the model ascomycete Podospora anserina and compared it with the previous method involving the formation of balanced heterokaryons. Both methods showed a good correlation. Heterokaryon formation was less quantifiable, but enabled to observe very rare events. Microscopic analysis evidenced that anastomoses were greatly influence by growth conditions and were severely impaired in the IDC mutants of the PaMpk1, PaMpk2, IDC1 and PaNox1 pathways. Yet some mutants readily formed heterokaryons, albeit with a delay when compared to the wild type. We also identified IDC(821), a new mutant presenting a phenotype similar to the other IDC mutants, including lack of anastomosis. Complete genome sequencing revealed that IDC(821) was affected in the orthologue of the Neurospora crassa So gene known to control anastomosis in several other ascomycetes.

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

    PubMed Central

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

    2013-01-01

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

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

    PubMed

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

    2016-01-01

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

  4. A Network of HMG-box Transcription Factors Regulates Sexual Cycle in the Fungus Podospora anserina

    PubMed Central

    Ait Benkhali, Jinane; Coppin, Evelyne; Brun, Sylvain; Peraza-Reyes, Leonardo; Martin, Tom; Dixelius, Christina; Lazar, Noureddine; van Tilbeurgh, Herman; Debuchy, Robert

    2013-01-01

    High-mobility group (HMG) B proteins are eukaryotic DNA-binding proteins characterized by the HMG-box functional motif. These transcription factors play a pivotal role in global genomic functions and in the control of genes involved in specific developmental or metabolic pathways. The filamentous ascomycete Podospora anserina contains 12 HMG-box genes. Of these, four have been previously characterized; three are mating-type genes that control fertilization and development of the fruit-body, whereas the last one encodes a factor involved in mitochondrial DNA stability. Systematic deletion analysis of the eight remaining uncharacterized HMG-box genes indicated that none were essential for viability, but that seven were involved in the sexual cycle. Two HMG-box genes display striking features. PaHMG5, an ortholog of SpSte11 from Schizosaccharomyces pombe, is a pivotal activator of mating-type genes in P. anserina, whereas PaHMG9 is a repressor of several phenomena specific to the stationary phase, most notably hyphal anastomoses. Transcriptional analyses of HMG-box genes in HMG-box deletion strains indicated that PaHMG5 is at the hub of a network of several HMG-box factors that regulate mating-type genes and mating-type target genes. Genetic analyses revealed that this network also controls fertility genes that are not regulated by mating-type transcription factors. This study points to the critical role of HMG-box members in sexual reproduction in fungi, as 11 out of 12 members were involved in the sexual cycle in P. anserina. PaHMG5 and SpSte11 are conserved transcriptional regulators of mating-type genes, although P. anserina and S. pombe diverged 550 million years ago. Two HMG-box genes, SOX9 and its upstream regulator SRY, also play an important role in sex determination in mammals. The P. anserina and S. pombe mating-type genes and their upstream regulatory factor form a module of HMG-box genes analogous to the SRY/SOX9 module, revealing a commonality of sex

  5. Identification of autophagy as a longevity-assurance mechanism in the aging model Podospora anserina

    PubMed Central

    Knuppertz, Laura; Hamann, Andrea; Pampaloni, Francesco; Stelzer, Ernst; Osiewacz, Heinz D

    2014-01-01

    The filamentous ascomycete Podospora anserina is a well-established aging model in which a variety of different pathways, including those involved in the control of respiration, ROS generation and scavenging, DNA maintenance, proteostasis, mitochondrial dynamics, and programmed cell death have previously been demonstrated to affect aging and life span. Here we address a potential role of autophagy. We provide data demonstrating high basal autophagy levels even in strains cultivated under noninduced conditions. By monitoring an N-terminal fusion of EGFP to the fungal LC3 homolog PaATG8 over the lifetime of the fungus on medium with and without nitrogen supplementation, respectively, we identified a significant increase of GFP puncta in older and in nitrogen-starved cultures suggesting an induction of autophagy during aging. This conclusion is supported by the demonstration of an age-related and autophagy-dependent degradation of a PaSOD1-GFP reporter protein. The deletion of Paatg1, which leads to the lack of the PaATG1 serine/threonine kinase active in early stages of autophagy induction, impairs ascospore germination and development and shortens life span. Under nitrogen-depleted conditions, life span of the wild type is increased almost 4-fold. In contrast, this effect is annihilated in the Paatg1 deletion strain, suggesting that the ability to induce autophagy is beneficial for this fungus. Collectively, our data identify autophagy as a longevity-assurance mechanism in P. anserina and as another surveillance pathway in the complex network of pathways affecting aging and development. These findings provide perspectives for the elucidation of the mechanisms involved in the regulation of individual pathways and their interactions. PMID:24584154

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

    PubMed Central

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

    1995-01-01

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

  7. Manganese rescues adverse effects on lifespan and development in Podospora anserina challenged by excess hydrogen peroxide.

    PubMed

    Grimm, Carolin; Osiewacz, Heinz D

    2015-03-01

    For biological systems, balancing cellular levels of reactive oxygen species (ROS) is of great importance because ROS are both, essential for cellular signaling and dangerous in causing molecular damage. Cellular ROS abundance is controlled by a delicate network of molecular pathways. Within this network, superoxide dismutases (SODs) are active in disproportion of the superoxide anion leading to the formation of hydrogen peroxide. The fungal aging model Podospora anserina encodes at least three SODs. One of these is the mitochondrial PaSOD3 isoform containing manganese as a cofactor. Previous work resulted in the selection of strains in which PaSod3 is strongly overexpressed. These strains display impairments in growth and lifespan. A computational model suggests a series of events to occur in Sod3 overexpressing strains leading to adverse effects due to elevated hydrogen peroxide levels. In an attempt to validate this model and to obtain more detailed information about the cellular responses involved in ROS balancing, we further investigated the PaSod3 overexpressing strains. Here we show that hydrogen peroxide levels are indeed strongly increased in the mutant strain. Surprisingly, this phenotype can be rescued by the addition of manganese to the growth medium. Strikingly, while we obtained no evidence for an antioxidant effect of manganese, we found that the metal is required for induction of components of the ROS scavenging network and lowers the hydrogen peroxide level of the mutant. A similar effect of manganese on lifespan reversion was obtained in wild-type strains challenged with exogenous hydrogen peroxide. It appears that manganese is limited under high hydrogen peroxide and suggests that a manganese-dependent activity leads to the induction of ROS scavenging components.

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

    PubMed Central

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

    2004-01-01

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

  9. Two NADPH oxidase isoforms are required for sexual reproduction and ascospore germination in the filamentous fungus Podospora anserina.

    PubMed

    Malagnac, Fabienne; Lalucque, Hervé; Lepère, Gersende; Silar, Philippe

    2004-11-01

    NADPH oxidases are enzymes that produce reactive oxygen species (ROS) using electrons derived from intracellular NADPH. In plants and mammals, ROS have been proposed to be second messengers that signal defence responses or cell proliferation. By inactivating PaNox1 and PaNox2, two genes encoding NADPH oxidases, we demonstrate the crucial role of these enzymes in the control of two key steps of the filamentous fungus Podospora anserina life cycle. PaNox1 mutants are impaired in the differentiation of fruiting bodies from their progenitor cells, and the deletion of the PaNox2 gene specifically blocks ascospore germination. Furthermore, we show that PaNox1 likely acts upstream of PaASK1, a MAPKKK previously implicated in stationary phase differentiation and cell degeneration. Using nitro blue tetrazolium (NBT) and diaminobenzidine (DAB) assays, we detect a regulated secretion of both superoxide and peroxide during P. anserina vegetative growth. In addition, two oxidative bursts are shown to occur during fruiting body development and ascospore germination. Analysis of mutants establishes that PaNox1, PaNox2, and PaASK1, as well as a still unknown additional source of ROS, modulate these secretions. Altogether, our data point toward a role for NADPH oxidases in signalling fungal developmental transitions with respect to nutrient availability. These enzymes are conserved in other multicellular eukaryotes, suggesting that early eukaryotes were endowed with a redox network used for signalling purposes.

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

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

    PubMed Central

    Coppin, E; Debuchy, R

    2000-01-01

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

  12. Genome-Wide Gene Expression Profiling of Fertilization Competent Mycelium in Opposite Mating Types in the Heterothallic Fungus Podospora anserina

    PubMed Central

    Coppin, Evelyne; Imbeaud, Sandrine; Grognet, Pierre; Delacroix, Hervé; Debuchy, Robert

    2011-01-01

    Background Mating-type loci in yeasts and ascomycotan filamentous fungi (Pezizomycotina) encode master transcriptional factors that play a critical role in sexual development. Genome-wide analyses of mating-type-specification circuits and mating-type target genes are available in Saccharomyces cerevisiae and Schizosaccharomyces pombe; however, no such analyses have been performed in heterothallic (self-incompatible) Pezizomycotina. The heterothallic fungus Podospora anserina serves as a model for understanding the basic features of mating-type control. Its mat+ and mat− mating types are determined by dissimilar allelic sequences. The mat− sequence contains three genes, designated FMR1, SMR1 and SMR2, while the mat+ sequence contains one gene, FPR1. FMR1 and FPR1 are the major regulators of fertilization, and this study presents a genome-wide view of their target genes and analyzes their target gene regulation. Methodology/Principal Findings The transcriptomic profiles of the mat+ and mat− strains revealed 157 differentially transcribed genes, and transcriptomic analysis of fmr1− and fpr1− mutant strains was used to determine the regulatory actions exerted by FMR1 and FPR1 on these differentially transcribed genes. All possible combinations of transcription repression and/or activation by FMR1 and/or FPR1 were observed. Furthermore, 10 additional mating-type target genes were identified that were up- or down-regulated to the same level in mat+ and mat− strains. Of the 167 genes identified, 32 genes were selected for deletion, which resulted in the identification of two genes essential for the sexual cycle. Interspecies comparisons of mating-type target genes revealed significant numbers of orthologous pairs, although transcriptional profiles were not conserved between species. Conclusions/Significance This study represents the first comprehensive genome-wide analysis of mating-type direct and indirect target genes in a heterothallic filamentous fungus

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

    PubMed Central

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

    2000-01-01

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

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

    PubMed Central

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

    2001-01-01

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

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

    PubMed Central

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

    1998-01-01

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

  16. Mating types and sexual development in filamentous ascomycetes.

    PubMed Central

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

    1997-01-01

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

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

    PubMed Central

    Contamine, Véronique; Zickler, Denise; Picard, Marguerite

    2004-01-01

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

  18. 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...

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

    PubMed Central

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

    2002-01-01

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

  20. Cyclophilin D Is Involved in the Regulation of Autophagy and Affects the Lifespan of P. anserina in Response to Mitochondrial Oxidative Stress

    PubMed Central

    Kramer, Piet; Jung, Alexander T.; Hamann, Andrea; Osiewacz, Heinz D.

    2016-01-01

    The mitochondrial permeability transition pore plays a key role in programmed cell death and the induction of autophagy. Opening of the pore is regulated by the mitochondrial peptidyl prolyl-cis, trans-isomerase cyclophilin D (CYPD). Previously it was shown in the aging model organism Podospora anserina that PaCYPD abundance increases during aging and that PaCypD overexpressors are characterized by accelerated aging. Here, we describe a role of PaCYPD in the regulation of autophagy. We found that the accelerated aging phenotype observed in a strain overexpressing PaCypD is not metacaspase-dependent but is accompanied by an increase of general autophagy and mitophagy, the selective autophagic degradation of mitochondria. It thus is linked to what has been defined as “autophagic cell death” or “type II” programmed cell death. Moreover, we found that the previously demonstrated age-related induction of autophagy in wild-type aging depends on the presence of PaCYPD. Deletion of PaCypD leads to a decrease in autophagy in later stages of age and under paraquat-mediated oxidative stress. Finally, we report that PaCYPD is also required for mitohormesis, the beneficial effect of mild mitochondrial stress. Thus, PaCYPD plays a key role in the context-dependent regulation of pathways leading to pro-survival and pro-death effects of autophagy. PMID:27683587

  1. Genomic evolution of the ascomycetous yeasts

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  2. The Kinetochore Interaction Network (KIN) of ascomycetes

    PubMed Central

    Freitag, Michael

    2016-01-01

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

  3. Dibenzofurans and derivatives from lichens and ascomycetes.

    PubMed

    Millot, Marion; Dieu, Amandine; Tomasi, Sophie

    2016-06-02

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

  4. Genomic Evolution of the Ascomycete Yeasts

    SciTech Connect

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

    2015-03-16

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

  5. 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

  6. Steroid toxicity and detoxification in ascomycetous fungi.

    PubMed

    Cvelbar, Damjana; Zist, Vanja; Kobal, Katja; Zigon, Dušan; Zakelj-Mavrič, Marija

    2013-02-25

    In the last couple of decades fungal infections have become a significant clinical problem. A major interest into fungal steroid action has been provoked since research has proven that steroid hormones are toxic to fungi and affect the host/fungus relationship. Steroid hormones were found to differ in their antifungal activity in ascomycetous fungi Hortaea werneckii, Saccharomyces cerevisiae and Aspergillus oryzae. Dehydroepiandrosterone was shown to be the strongest inhibitor of growth in all three varieties of fungi followed by androstenedione and testosterone. For their protection, fungi use several mechanisms to lower the toxic effects of steroids. The efficiency of biotransformation in detoxification depended on the microorganism and steroid substrate used. Biotransformation was a relatively slow process as it also depended on the growth phase of the fungus. In addition to biotransformation, steroid extrusion out of the cells contributed to the lowering of the active intracellular steroid concentration. Plasma membrane Pdr5 transporter was found to be the most effective, followed by Snq2 transporter and vacuolar transporters Ybt1 and Ycf1. Proteins Aus1 and Dan1 were not found to be involved in steroid import. The research of possible targets of steroid hormone action in fungi suggests that steroid hormones inhibit ergosterol biosynthesis in S. cerevisiae and H. werneckii. Results of this inhibition caused changes in the sterol content of the cellular membrane. The presence of steroid hormones most probably causes the degradation of the Tat2 permease and impairment of tryptophan import.

  7. Phylogenetics of Saccharomycetales, the ascomycete yeasts.

    PubMed

    Suh, Sung-Oui; Blackwell, Meredith; Kurtzman, Cletus P; Lachance, Marc-André

    2006-01-01

    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 species account for most human mycotic infections, and fewer than 10 species are plant pathogens. Yeasts are responsible for important industrial and biotechnological processes, including baking, brewing and synthesis of recombinant proteins. Species such as Saccharomyces cerevisiae are model organisms in research, some of which led to a Nobel Prize. Yeasts usually reproduce asexually by budding, and their sexual states are not enclosed in a fruiting body. The group also is well defined by synapomorphies visible at the ultrastructural level. Yeast identification and classification changed dramatically with the availability of DNA sequencing. Species identification now benefits from a constantly updated sequence database and no longer relies on ambiguous growth tests. A phylogeny based on single gene analyses has shown the order to be remarkably divergent despite morphological similarities among members. The limits of many previously described genera are not supported by sequence comparisons, and multigene phylogenetic studies are under way to provide a stable circumscription of genera, families and orders. One recent multigene study has resolved species of the Saccharomycetaceae into genera that differ markedly from those defined by analysis of morphology and growth responses, and similar changes are likely to occur in other branches of the yeast tree as additional sequences become available.

  8. [Comparison of genomes between Aspergillus nidulans and 30 filamentous ascomycetes].

    PubMed

    Zeng, Zhao-Qing; Zhao, Fu-Yong; Hsiang, Tom; Yu, Zhi-He

    2010-11-01

    To investigate the conserved homologs of filamentous ascomycetes genomes, the local fungal genome database used in this analysis was established, which consisted of 31 latest and complete genome data publicly available on the Internet. An expectation value cutoff of 0.1 was used to identify significant hits. Each complete gene set of the query genome Aspergillus nidulans genome with 10,560 annotated genes was splitted into individual FASTA files with Seqverter and then compared separately against each filamentous ascomycete genome using Standalone BLASTN. The result indicated that the number of matches reflected the evolutional relationships of the filamentous ascomycetes analysed. Of 10,560 genes in Aspergillus nidulans genome, 924 had match sequences with other 30 filamentous ascomycetes ones. The number of homology sequences were 6, 3, 6, and 6 at E-values in the range of 10(-5) to 0.1, 10(-30) to 10(-5), 10(-100) to 10(-30) and 0 to 1000(-100), respectively. Six homologs at E-values ranging from 10(-5) to 0.1 and 3 at E-values ranging from 10(-30) to 10(-5) were variable, while the 6 at E-values ranging from 0 to 10(-100) were highly conserved based on the alignments using ClustalX. Six homologs were relatively conserved at E-values in the range of 10(-100) to 10(-30), which can be used in phylogeny of these filamentous ascomycetes in this study.

  9. Antifungal Susceptibility Testing of Ascomycetous Yeasts Isolated from Animals

    PubMed Central

    Álvarez-Pérez, Sergio; García, Marta E.; Peláez, Teresa; Martínez-Nevado, Eva

    2016-01-01

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

  10. Chromosome and Megaplasmid Sequences of Borrelia anserina (Sakharoff 1891), the Agent of Avian Spirochetosis and Type Species of the Genus

    PubMed Central

    Elbir, Haitham; Sitlani, Parth; Bergström, Sven

    2017-01-01

    ABSTRACT Sequences of the linear chromosome and plasmids of Borrelia anserina, the cause of avian spirochetosis of poultry, revealed a smaller genome than those of other Borrelia spp. transmitted by argasid ticks. Missing or disrupted genes included a dam methylase and those in the pathway for synthesis of phospholipids from glycerol. PMID:28302772

  11. 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.

  12. Phenolic profile of Potentilla anserina L. (Rosaceae) herb of siberian origin and development of a rapid method for simultaneous determination of major Phenolics in P. anserina pharmaceutical products by microcolumn RP-HPLC-UV.

    PubMed

    Olennikov, Daniil N; Kashchenko, Nina I; Chirikova, Nadezhda K; Kuz'mina, Sargylana S

    2014-12-24

    A chemical study of Potentilla anserina L. herb (Rosaceae) of Siberian origin led to the isolation of 17 compounds. Three ellagitannins-potentillin, agrimonic acid A and B-are reported for the first time in this species. With a view to rapid quantitative analysis, a new method was developed for simultaneous determination of major phenolic compounds in P. anserina, including caffeic acid, myricetin-3-O-glucuronide, agrimoniin, ellagic acid, miquelianin, isorhamnetin-3-O-glucuronide, and kaempferol-3-O-rhamnoside. The quantitative determination was conducted by microcolumn reversed phase high-performance liquid chromatography with UV detection. Separation was performed using a ProntoSIL-120-5-C18 AQ column (60 mm × 1 mm × 5 μm) with six-step gradient elution of aqueous 0.2 М LiClO4 in 0.006 M HClO4 and acetonitrile as mobile phases. The components were quantified by HPLC-UV at 270 nm. All calibration curves showed good linearity (r2 > 0.999) within test ranges. The reproducibility was evaluated by intra- and inter-day assays, and RSD values were less than 2.8%. The recoveries were between 97.15 and 102.38%. The limits of detection ranged from 0.21 to 1.94 μg/mL, and limits of quantification ranged from 0.65 to 5.88 μg/mL, respectively. Various solvents, extraction methods, temperatures, and times were evaluated to obtain the best extraction efficiency. The developed method was successfully applied for the analysis of selected pharmaceutical products: 12 batches of P. anserina herb collected from three Siberian regions (Yakutia, Buryatia, Irkutsk), two commercial samples of P. anserina herb, and some preparations (liquid extract, tincture, decoction, infusion, and dry extract).

  13. Deletion of the RING-finger peroxin 2 gene in Aspergillus nidulans does not affect meiotic development.

    PubMed

    Hynes, Michael J; Murray, Sandra L; Kahn, Freya K

    2010-05-01

    Peroxins are required for protein import into peroxisomes as well as for peroxisome biogenesis and proliferation. Loss-of-function mutations in genes for the RING-finger peroxins Pex2, Pex10 and Pex12 lead to a specific block in meiosis in the ascomycete Podospora anserina. However, loss of protein import into peroxisomes does not result in this meiotic defect. Therefore, it has been suggested that these peroxins have a specific function required for meiosis. To determine whether this role is conserved in other filamentous fungi, we have deleted the gene encoding Pex2 in Aspergillus nidulans. The phenotypes resulting from this deletion are no different from those of previously isolated pex mutants affected in peroxisomal protein import, and viable ascospores are produced in selfed crosses. Therefore, the role of the RING-finger peroxins in meiosis is not conserved in filamentous ascomycetes.

  14. 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.

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

    PubMed

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

    2015-09-01

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

  16. A novel class of peptide pheromone precursors in ascomycetous fungi

    PubMed Central

    Schmoll, Monika; Seibel, Christian; Tisch, Doris; Dorrer, Marcel; Kubicek, Christian P

    2010-01-01

    Recently, sexual development in the heterothallic ascomycete Trichoderma reesei (anamorph of Hypocrea jecorina) has been achieved and thus initiated attempts to elucidate regulation and determinants of this process. While the α-type pheromone of this fungus fits the consensus known from other fungi, the assumed a-type peptide pheromone precursor shows remarkably unusual characteristics: it comprises three copies of the motif (LI)GC(TS)VM thus constituting a CAAX domain at the C-terminus and two Kex2-protease sites. This structure shares characteristics of both a- and α-type peptide pheromone precursors. Presence of hybrid-type peptide pheromone precursor 1 (hpp1) is essential for male fertility, thus indicating its functionality as a peptide pheromone precursor, while its phosphorylation site is not relevant for this process. However, sexual development in a female fertile background is not perturbed in the absence of hpp1, which rules out a higher order function in this process. Open reading frames encoding proteins with similar characteristics to HPP1 were also found in Fusarium spp., of which Fusarium solani still retains a putative a-factor-like protein, but so far in no other fungal genome available. We therefore propose the novel class of h-type (hybrid) peptide pheromone precursors with H. jecorina HPP1 as the first member of this class. PMID:20735770

  17. Impact of recent molecular phylogenetic studies on classification of ascomycete yeasts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Analyses of concatenated gene sequences as well as whole genome sequences are resolving relationships among the ascomycete yeasts (Saccharomycotina), thus allowing classification of members of this subphylum to be based on phylogeny. In addition, changes implemented in the new Botanical Code [Intern...

  18. RNA Editing During Sexual Development Occurs in Distantly Related Filamentous Ascomycetes

    PubMed Central

    Teichert, Ines; Dahlmann, Tim A.; Kück, Ulrich

    2017-01-01

    RNA editing is a post-transcriptional process that modifies RNA molecules leading to transcript sequences that differ from their template DNA. A-to-I editing was found to be widely distributed in nuclear transcripts of metazoa, but was detected in fungi only recently in a study of the filamentous ascomycete Fusarium graminearum that revealed extensive A-to-I editing of mRNAs in sexual structures (fruiting bodies). Here, we searched for putative RNA editing events in RNA-seq data from Sordaria macrospora and Pyronema confluens, two distantly related filamentous ascomycetes, and in data from the Taphrinomycete Schizosaccharomyces pombe. Like F. graminearum, S. macrospora is a member of the Sordariomycetes, whereas P. confluens belongs to the early-diverging group of Pezizomycetes. We found extensive A-to-I editing in RNA-seq data from sexual mycelium from both filamentous ascomycetes, but not in vegetative structures. A-to-I editing was not detected in different stages of meiosis of S. pombe. A comparison of A-to-I editing in S. macrospora with F. graminearum and P. confluens, respectively, revealed little conservation of individual editing sites. An analysis of RNA-seq data from two sterile developmental mutants of S. macrospora showed that A-to-I editing is strongly reduced in these strains. Sequencing of cDNA fragments containing more than one editing site from P. confluens showed that at the beginning of sexual development, transcripts were incompletely edited or unedited, whereas in later stages transcripts were more extensively edited. Taken together, these data suggest that A-to-I RNA editing is an evolutionary conserved feature during fruiting body development in filamentous ascomycetes. PMID:28338982

  19. RNA editing during sexual development occurs in distantly related filamentous ascomycetes.

    PubMed

    Teichert, Ines; Dahlmann, Tim; Kück, Ulrich; Nowrousian, Minou

    2017-03-09

    RNA editing is a posttranscriptional process that modifies RNA molecules leading to transcript sequences that differ from their template DNA. A-to-I editing was found to be widely distributed in nuclear transcripts of metazoa, but was detected in fungi only recently in a study of the filamentous ascomycete Fusarium graminearum that revealed extensive A-to-I editing of mRNAs in sexual structures (fruiting bodies). Here, we searched for putative RNA editing events in RNA-seq data from Sordaria macrospora and Pyronema confluens, two distantly related filamentous ascomycetes, and in data from the Taphrinomycete Schizosaccharomyces pombe. Like F. graminearum, S. macrospora is a member of the Sordariomycetes, whereas P. confluens belongs to the early-diverging group of Pezizomycetes. We found extensive A-to-I editing in RNA-seq data from sexual mycelium from both filamentous ascomycetes, but not in vegetative structures. A-to-I editing was not detected in different stages of meiosis of S. pombe. A comparison of A-to-I editing in S. macrospora with F. graminearum and P. confluens, respectively, revealed little conservation of individual editing sites. An analysis of RNA-seq data from two sterile developmental mutants of S. macrospora showed that A-to-I editing is strongly reduced in these strains. Sequencing of cDNA fragments containing more than one editing site from P. confluens showed that at the beginning of sexual development, transcripts were incompletely edited or unedited, whereas in later stages transcripts were more extensively edited. Taken together, these data suggest that A-to-I RNA editing is an evolutionary conserved feature during fruiting body development in filamentous ascomycetes.

  20. Causes and consequences of variability in peptide mating pheromones of ascomycete fungi.

    PubMed

    Martin, Simon H; Wingfield, Brenda D; Wingfield, Michael J; Steenkamp, Emma T

    2011-07-01

    The reproductive genes of fungi, like those of many other organisms, are thought to diversify rapidly. This phenomenon could be associated with the formation of reproductive barriers and speciation. Ascomycetes produce two classes of mating type-specific peptide pheromones. These are required for recognition between the mating types of heterothallic species. Little is known regarding the diversity or the extent of species specificity in pheromone peptides among these fungi. We compared the putative protein-coding DNA sequences of the 2 pheromone classes from 70 species of Ascomycetes. The data set included previously described pheromones and putative pheromones identified from genomic sequences. In addition, pheromone genes from 12 Fusarium species in the Gibberella fujikuroi complex were amplified and sequenced. Pheromones were largely conserved among species in this complex and, therefore, cannot alone account for the reproductive barriers observed between these species. In contrast, pheromone peptides were highly diverse among many other Ascomycetes, with evidence for both positive diversifying selection and relaxed selective constraint. Repeats of the α-factor-like pheromone, which occur in tandem arrays of variable copy number, were found to be conserved through purifying selection and not concerted evolution. This implies that sequence specificity may be important for pheromone reception and that interspecific differences may indeed be associated with functional divergence. Our findings also suggest that frequent duplication and loss causes the tandem repeats to experience "birth-and-death" evolution, which could in fact facilitate interspecific divergence of pheromone peptide sequences.

  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-Tolić, L.; Santelli, C. M.; Hansel, C. M.

    2014-12-01

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

  2. 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.

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

    SciTech Connect

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

    2016-07-19

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

  4. Eisosome Organization in the Filamentous AscomyceteAspergillus nidulans▿†

    PubMed Central

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

    2010-01-01

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

  5. Molecular organization of the mating-type loci in the homothallic Ascomycete Eupenicillium crustaceum.

    PubMed

    Pöggeler, Stefanie; O'Gorman, Céline M; Hoff, Birgit; Kück, Ulrich

    2011-07-01

    Eupenicillium species are the teleomorphic (sexual) forms of anamorphic (asexual) members of the genus Penicillium, which contains many species of industrial importance. Here we describe the first molecular analysis of the mating-type (MAT) locus from a homothallic (self-fertile) Eupenicillium species, E. crustaceum. This ascomycete is a sexual relative of the penicillin producer Penicillium chrysogenum, which while long considered asexual, was recently shown to possess the required genetic machinery for heterothallic breeding. The E. crustaceum genome contains two MAT loci, MAT1-1 and MAT1-2, in an arrangement characteristic of other known homothallic euascomycetes, such as Neosartorya fischeri. MAT1-1 is flanked by conserved APN2 (DNA lyase) and SLA2 (cytoskeleton assembly control) genes and encodes a homologue of the α-box domain protein MAT1-1-1. Conversely, MAT1-2 carries a HMG-domain gene MAT1-2-1, and is flanked by a degenerate SLA2 gene and an intact homologue of the P. chrysogenum ORF Pc20g08960. Here we demonstrate the transcriptional expression of both mating-type genes during vegetative development. Furthermore, the MAT1-1-1 and MAT1-2-1 sequences were used to resolve the phylogenetic relationship of E. crustaceum with other ascomycetes. Phylogenetic trees confirmed a very close relationship between the homothallic E. crustaceum and the supposedly heterothallic P. chrysogenum. This close taxonomic association makes E. crustaceum an ideal candidate for future expression and evolutionary studies of sexual reproduction, with the ultimate aim of inducing sex in P. chrysogenum.

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

    PubMed Central

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

    2016-01-01

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

  7. Vesicular transport in Histoplasma capsulatum: an effective mechanism for trans-cell wall transfer of proteins and lipids in ascomycetes

    PubMed Central

    Albuquerque, Priscila Costa; Nakayasu, Ernesto S.; Rodrigues, Marcio L.; Frases, Susana; Casadevall, Arturo; Zancope-Oliveira, Rosely M.; Almeida, Igor C.; Nosanchuk, Joshua D.

    2008-01-01

    Vesicular secretion of macromolecules has recently been described in the basidiomycete Cryptococcus neoformans raising the question as to whether ascomycetes similarly utilize vesicles for transport. In the present study, we examine whether the clinically important ascomycete Histoplasma capsulatum produce vesicles and utilized these structures to secrete macromolecules. Transmission electron microscopy (TEM) show transcellular secretion of vesicles by yeast cells. Proteomic and lipidomic analyses of vesicles isolated from culture supernatants reveals a rich collection of macromolecules involved in diverse processes including metabolism, cell recycling, signaling, and virulence. The results demonstrate that H. capsulatum can utilize a trans-cell wall vesicular transport secretory mechanism to promote virulence. Additionally, TEM of supernatants collected from Candida albicans, Candida parapsilosis, Sporothrix schenckii, and Saccharomyces cerevisiae document that vesicles are similarly produced by additional ascomycetes. The vesicles from H. capsulatum react with immune serum from patients with histoplasmosis providing an association of the vesicular products with pathogenesis. The findings support the proposal that vesicular secretion is a general mechanism in fungi for the transport of macromolecules related to virulence and that this process could be a target for novel therapeutics. PMID:18419773

  8. 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.

  9. Antarctomyces pellizariae sp. nov., a new, endemic, blue, snow resident psychrophilic ascomycete fungus from Antarctica.

    PubMed

    de Menezes, Graciéle C A; Godinho, Valéria M; Porto, Bárbara A; Gonçalves, Vívian N; Rosa, Luiz H

    2017-03-01

    In the present study, we have identified and characterised a new snow resident ascomycete blue stain fungus from Antarctica named Antarctomyces pellizariae sp. nov. Menezes, Godinho, Porto, Gonçalves and Rosa, using polyphasic taxonomy techniques. This fungal species was recovered from the seasonal snow of the Antarctic Peninsula. Antarctomyces pellizariae displayed different macro- and micromorphology when compared with A. psychrotrophicus Stchigel and Guarro, the only other Antarctomyces species reported until date. Antarctomyces pellizariae showed psychrophilic behavior and very low growth rate at 22-25 °C, quite different from A. psychrotrophicus that has a higher growth rate at mesophilic temperatures. In addition, micromorphological characteristics and the analysis of the nuclear rDNA internal transcribed spacer, β-tubulin, and RNA polymerase II regions revealed that A. pellizariae is a new species that is related to A. psychrotrophicus and Thelebolus species. Since the Antarctic Peninsula is reported to be one of the main regions of the earth experiencing the effects of global change in climate, species, such as A. pellizariae, might provide information about these effects on the endemic Antarctic biota. In addition, A. pellizariae displayed psychrophilic behavior and might be a source of interesting anti-freeze compounds that might prove useful in biotechnological processes.

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

    PubMed

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

    2003-11-01

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

  11. 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

  12. Interactions of sterile-cultured lichen-forming ascomycetes with asbestos fibres.

    PubMed

    Favero-Longo, Sergio Enrico; Girlanda, Mariangela; Honegger, Rosmarie; Fubini, Bice; Piervittori, Rosanna

    2007-04-01

    Sterile cultured isolates of lichen-forming ascomycetes have not yet been used to investigate mycobiont-mineral substrate interactions under controlled conditions. In this study Candelariella vitellina, Xanthoparmelia tinctina and Lecanora rupicola mycobionts were isolated and inoculated with chrysotile fibres in the laboratory, in order to verify whether physical and chemical weathering processes, which were already described in the field, may be reproduced in vitro. Tight adhesion of hyphae to chrysotile fibres was observed in all species. The adhering hyphae affected the chemical composition of asbestos fibres, with the selective depletion of magnesium being a prominent feature, as is the case in field conditions. Oxalic acid and pulvinic acid, mycobiont-derived metabolites of X. tinctina and C. vitellina, were involved in the weathering action. Time and environmental factors and the absence of biological synergisms strongly limited the chemical weathering in vitro compared with what was observed in the field. Nevertheless, the results show that in vitro incubation of sterile-cultured lichen-forming fungi with minerals is a practicable experimental system to investigate the weathering effects of different mycobionts and fungal compounds under controlled conditions.

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

    PubMed

    Kroken, Scott; Glass, N Louise; Taylor, John W; Yoder, O C; Turgeon, B Gillian

    2003-12-23

    Fungal type I polyketides (PKs) are synthesized by PK synthases (PKSs) and include well known secondary metabolites such as the anticholesterol drug lovastatin and the potent natural carcinogen aflatoxin. Other type I PKs are known to be virulence factors 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 type I PKs. The resulting genealogy, constructed by using the highly conserved PKS ketosynthase (KS) domain, indicated that: (i). Species within subphylum Pezizomycotina (phylum Ascomycota) but not early diverging ascomycetes, like Saccharomyces cerevisiae (Saccharomycotina) or Schizosaccharomyces pombe (Taphrinomycotina), had large numbers (7-25) of PKS genes. (ii). Bacteria and fungi had separate groups of PKS genes; the few exceptions are the likely result of horizontal gene transfer from bacteria to various sublineages of fungi. (iii). The bulk of genes encoding fungal PKSs fell into eight groups. Four groups were predicted to synthesize variously reduced PKs, and four groups were predicted to make unreduced PKs. (iv). Species within different classes of Pezizomycotina shared the same groups of PKS genes. (v). Different fungal genomes shared few putative orthologous PKS genes, even between closely related genomes in the same class or genus. (vi) The discontinuous distributions of orthologous PKSs among fungal species can be explained by gene duplication, divergence, and gene loss; horizontal gene transfer among fungi does not need to be invoked.

  14. Asexual cephalosporin C producer Acremonium chrysogenum carries a functional mating type locus.

    PubMed

    Pöggeler, Stefanie; Hoff, Birgit; Kück, Ulrich

    2008-10-01

    Acremonium chrysogenum, the fungal producer of the pharmaceutically relevant beta-lactam antibiotic cephalosporin C, is classified as asexual because no direct observation of mating or meiosis has yet been reported. To assess the potential of A. chrysogenum for sexual reproduction, we screened an expressed sequence tag library from A. chrysogenum for the expression of mating type (MAT) genes, which are the key regulators of sexual reproduction. We identified two putative mating type genes that are homologues of the alpha-box domain gene, MAT1-1-1 and MAT1-1-2, encoding an HPG domain protein defined by the presence of the three invariant amino acids histidine, proline, and glycine. In addition, cDNAs encoding a putative pheromone receptor and pheromone-processing enzymes, as well as components of a pheromone response pathway, were found. Moreover, the entire A. chrysogenum MAT1-1 (AcMAT1-1) gene and regions flanking the MAT region were obtained from a genomic cosmid library, and sequence analysis revealed that in addition to AcMAT1-1-1 and AcMAT1-1-2, the AcMAT1-1 locus comprises a third mating type gene, AcMAT1-1-3, encoding a high-mobility-group domain protein. The alpha-box domain sequence of AcMAT1-1-1 was used to determine the phylogenetic relationships of A. chrysogenum to other ascomycetes. To determine the functionality of the AcMAT1-1 locus, the entire MAT locus was transferred into a MAT deletion strain of the heterothallic ascomycete Podospora anserina (the PaDeltaMAT strain). After fertilization with a P. anserina MAT1-2 (MAT(+)) strain, the corresponding transformants developed fruiting bodies with mature ascospores. Thus, the results of our functional analysis of the AcMAT1-1 locus provide strong evidence to hypothesize a sexual cycle in A. chrysogenum.

  15. Comparative Xylose Metabolism among the Ascomycetes C. albicans, S. stipitis and S. cerevisiae

    PubMed Central

    Lépine, Guylaine; Askew, Chris; Raymond, Martine; Whiteway, Malcolm; Wu, Cunle

    2013-01-01

    The ascomycetes Candida albicans, Saccharomyces cerevisiae and Scheffersomyces stipitis metabolize the pentose sugar xylose very differently. S. cerevisiae fails to grow on xylose, while C. albicans can grow, and S. stipitis can both grow and ferment xylose to ethanol. However, all three species contain highly similar genes that encode potential xylose reductases and xylitol dehydrogenases required to convert xylose to xylulose, and xylulose supports the growth of all three fungi. We have created C. albicans strains deleted for the xylose reductase gene GRE3, the xylitol dehydrogenase gene XYL2, as well as the gre3 xyl2 double mutant. As expected, all the mutant strains cannot grow on xylose, while the single gre3 mutant can grow on xylitol. The gre3 and xyl2 mutants are efficiently complemented by the XYL1 and XYL2 from S. stipitis. Intriguingly, the S. cerevisiae GRE3 gene can complement the Cagre3 mutant, while the ScSOR1 gene can complement the Caxyl2 mutant, showing that S. cerevisiae contains the enzymatic capacity for converting xylose to xylulose. In addition, the gre3 xyl2 double mutant of C. albicans is effectively rescued by the xylose isomerase (XI) gene of either Piromyces or Orpinomyces, suggesting that the XI provides an alternative to the missing oxido-reductase functions in the mutant required for the xylose-xylulose conversion. Overall this work suggests that C. albicans strains engineered to lack essential steps for xylose metabolism can provide a platform for the analysis of xylose metabolism enzymes from a variety of species, and confirms that S. cerevisiae has the genetic potential to convert xylose to xylulose, although non-engineered strains cannot proliferate on xylose as the sole carbon source. PMID:24236198

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

    SciTech Connect

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

    2012-07-16

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

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

    PubMed

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

    2012-07-31

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

  18. Molecular and ultrastructural characterization of two ascomycetes found on sunken wood off Vanuatu islands in the deep Pacific ocean.

    PubMed

    Dupont, Joëlle; Magnin, Sandrine; Rousseau, Florence; Zbinden, Magali; Frebourg, Ghislaine; Samadi, Sarah; de Forges, Bertrand Richer; Jones, E B Gareth

    2009-12-01

    A new genus of a deep-sea ascomycete with one new species, Alisea longicolla, is described based on analyses of 18S and 28S rDNA sequences and morphological characters. A. longicolla was found together with Oceanitis scuticella, on small twigs and sugar cane debris trawled from the bottom of the Pacific Ocean off Vanuatu Islands. Molecular and morphological characters indicate that both fungi are members of Halosphaeriaceae. Within this family, O. scuticella is phylogenetically related to Ascosalsum and shares similar ascospore morphology and appendage ontogeny. The genus Ascosalsum is considered congeneric with Oceanitis and Ascosalsum cincinnatulum, Ascosalsum unicaudatum and Ascosalsum viscidulum are transferred to Oceanitis, an earlier generic name.

  19. Carbohydrate and Amino Acid Metabolism in the Ectomycorrhizal Ascomycete Sphaerosporella brunnea during Glucose Utilization 1

    PubMed Central

    Martin, Francis; Ramstedt, Mauritz; Söderhäll, Kenneth; Canet, Daniel

    1988-01-01

    Nuclear magnetic resonance spectroscopy was utilized to study the metabolism of [1-13C]glucose in mycelia of the ectomycorrhizal ascomycete Sphaerosporella brunnea. The main purpose was to assess the biochemical pathways for the assimilation of glucose and to identify the compounds accumulated during glucose assimilation. The majority of the 13C label was incorporated into mannitol, while glycogen, trehalose and free amino acids were labeled to a much lesser extent. The high enrichment of the C1/C6 position of mannitol indicated that the polyol was formed via a direct route from absorbed glucose. Randomization of the 13C label was observed to occur in glucose and trehalose leading to the accumulation of [1,6-13C]trehalose and [1,6-13C]glucose. This suggests that the majority of the glucose carbon used to form trehalose was cycled through the metabolically active mannitol pool. The proportion of label entering the free amino acids represented 38% of the soluble 13C after 6 hours of continuous glucose labeling. Therefore, amino acid biosynthesis is an important sink of assimilated carbon. Carbon-13 was incorporated into [3-13C]alanine and [2-13C]-, [3-13C]-, and [4-13C]glutamate and glutamine. From the analysis of the intramolecular 13C enrichment of these amino acids, it is concluded that [3-13C]pyruvate, arising from [1-13C]glucose catabolism, was used by alanine aminotransferase, pyruvate dehydrogenase, and pyruvate carboxylase (or phosphoenolpyruvate carboxykinase). Intramolecular 13C labeling patterns of glutamate and glutamine were similar and are consistent with the operation of the Krebs cycle. There is strong evidence for (a) randomization of the label on C2 and C3 positions of oxaloacetate via malate dehydrogenase and fumarase, and (b) the dual biosynthetic and respiratory role of the citrate synthase, aconitase, and isocitrate dehydrogenase reactions. The high flux of carbon through the carboxylation (presumably pyruvate carboxylase) step indicates that CO

  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. The draft genome sequence of the ascomycete fungus Penicillium subrubescens reveals a highly enriched content of plant biomass related CAZymes compared to related fungi.

    PubMed

    Peng, Mao; Dilokpimol, Adiphol; Mäkelä, Miia R; Hildén, Kristiina; Bervoets, Sander; Riley, Robert; Grigoriev, Igor V; Hainaut, Matthieu; Henrissat, Bernard; de Vries, Ronald P; Granchi, Zoraide

    2017-03-20

    Here we report the genome sequence of the ascomycete saprobic fungus Penicillium subrubescens FBCC1632/CBS132785 isolated from a Jerusalem artichoke field in Finland. The 39.75Mb genome containing 14,188 gene models is highly similar for that reported for other Penicillium species, but contains a significantly higher number of putative carbohydrate active enzyme (CAZyme) encoding genes.

  2. Valorization of sugar-to-ethanol process waste vinasse: A novel biorefinery approach using edible ascomycetes filamentous fungi.

    PubMed

    Nair, Ramkumar B; Taherzadeh, Mohammad J

    2016-12-01

    The aim of the present work was to study the integration of edible ascomycetes filamentous fungi into the existing sugar- or molasses-to-ethanol processes, to grow on vinasse or stillage and produce ethanol and protein-rich fungal biomass. Two fungal strains, Neurospora intermedia and Aspergillus oryzae were examined in shake flasks and airlift-bioreactors, resulting in reduction of vinasse COD by 34% and viscosity by 21%. Utilization of glycerol and sugars were observed, yielding 202.4 or 222.8g dry fungal biomass of N. intermedia or A. oryzae respectively, per liter of vinasse. Integration of the current process at an existing ethanol facility producing about 100,000m(3) of ethanol per year could produce around 200,000-250,000tons of dry fungal biomass (40-45% protein) together with about 8800-12,600m(3) extra ethanol (8.8-12.6% of production-rate improvement).

  3. Tetrapisispora namnaonensis sp. nov., a novel ascomycetous yeast species isolated from forest soil of Nam Nao National Park, Thailand.

    PubMed

    Sumpradit, Tawatchai; Limtong, Savitree; Yongmanitchai, Wichien; Kawasaki, Hiroko; Seki, Tatsuji

    2005-07-01

    Twenty-one strains of a novel ascomycetous yeast species were isolated from soil collected in three kinds of natural forest, namely a dry dipterocarp forest, a mixed deciduous forest and a pine forest, in Nam Nao National Park, Phetchabun province, Thailand. The strains formed asci containing one to four ovoid to reniform ascospores, assimilated glucose, galactose and glycerol, fermented glucose and galactose vigorously and contained ubiquinone Q-6, indicating that they belonged to the genus Tetrapisispora. A comparative analysis of the small subunit rDNA (SSU rDNA) and the D1/D2 domain of the large subunit rDNA (LSU rDNA) of all available sequences for ascomycetous yeasts confirmed that the strains were phylogenetically related to the genus Tetrapisispora. All strains had identical nucleotide sequences in the D1/D2 domain of the LSU rDNA and differed from the nearest species, Tetrapisispora arboricola IFO 10925(T), by 6.4% nucleotide substitutions. The strains differed from Tetrapisispora arboricola by the ability to assimilate D-gluconic acid, the inability to grow on 50% glucose medium, the nuclear DNA base composition and deliquescent asci. The strains were differentiated from the other four species of Tetrapisispora on the basis of trehalose assimilation, the ability to grow on 50% glucose or 10% NaCl plus 5% glucose, vitamin requirement, the nuclear DNA base composition and the type of ascus. Based on the characteristics mentioned above, the strains are recognized as a single novel species of the genus Tetrapisispora and the name Tetrapisispora namnaonensis sp. nov. is proposed. The type strain is TN1-01(T) (=TISTR 5828(T)=JCM 12664(T)=CBS 10093(T)).

  4. A new pullulan and a branched (1-->3)-, (1-->6)-linked beta-glucan from the lichenised ascomycete Teloschistes flavicans.

    PubMed

    Reis, Rodrigo A; Tischer, Cesar A; Gorin, Philip A J; Iacomini, Marcello

    2002-04-23

    The polysaccharides formed on hot alkaline extraction of the ascomycetous lichen Teloschistes flavicans were fractionated to give two glucans, which were characterised by methylation analysis and 1D and 2D NMR spectroscopy. One was a branched beta-glucan containing (1-->3) and (1-->6) linkages, a structure which is more typical of basidiomycetes rather than ascomycetes, which have linear glucans. The other was an alpha-glucan with alternating (1-->4) and (1-->6) linkages, found for the first time in Nature. This structure can be classified as a pullulan, which has been isolated from the fungi Aureobasidium pullulans, Tremella mesenterica, and Cyttaria harioti, but has different ratios of the component glycosidic linkages. The significance of the presence of the isolated alpha- and beta-glucans is discussed.

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

    SciTech Connect

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

    2014-11-01

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

  6. Vegetative incompatibility in filamentous fungi: a roundabout way of understanding the phenomenon.

    PubMed

    Loubradou, G; Turcq, B

    2000-05-01

    Vegetative incompatibility limits heterokaryon formation in fungi. It results from genetic differences at specific loci (het loci). Characterization of het genes and, more recently, of incompatibility reaction suppressors has, provided insight into the mechanisms involved. A link between development, vegetative incompatibility and signaling pathways has been established in Podospora anserina.

  7. High-Coverage ITS Primers for the DNA-Based Identification of Ascomycetes and Basidiomycetes in Environmental Samples

    PubMed Central

    Yamamoto, Satoshi; Sato, Hirotoshi

    2012-01-01

    The kingdom Fungi is estimated to include 1.5 million or more species, playing key roles as decomposers, mutualists, and parasites in every biome on the earth. To comprehensively understand the diversity and ecology of this huge kingdom, DNA barcoding targeting the internal transcribed spacer (ITS) region of the nuclear ribosomal repeat has been regarded as a prerequisite procedure. By extensively surveying ITS sequences in public databases, we designed new ITS primers with improved coverage across diverse taxonomic groups of fungi compared to existing primers. An in silico analysis based on public sequence databases indicated that the newly designed primers matched 99% of ascomycete and basidiomycete ITS taxa (species, subspecies or varieties), causing little taxonomic bias toward either fungal group. Two of the newly designed primers could inhibit the amplification of plant sequences and would enable the selective investigation of fungal communities in mycorrhizal associations, soil, and other types of environmental samples. Optimal PCR conditions for the primers were explored in an in vitro investigation. The new primers developed in this study will provide a basis for ecological studies on the diversity and community structures of fungi in the era of massive DNA sequencing. PMID:22808280

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

    PubMed Central

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

    2015-01-01

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

  9. Primer Sets Developed To Amplify Conserved Genes from Filamentous Ascomycetes Are Useful in Differentiating Fusarium Species Associated with Conifers

    PubMed Central

    Donaldson, G. C.; Ball, L. A.; Axelrood, P. E.; Glass, N. L.

    1995-01-01

    We examined the usefulness of primer sets designed to amplify introns within conserved genes in filamentous ascomycetes to differentiate 35 isolates representing six different species of Fusarium commonly found in association with conifer seedlings. We analyzed restriction fragment length polymorphisms (RFLP) in five amplified PCR products from each Fusarium isolate. The primers used in this study were constructed on the basis of sequence information from the H3, H4, and (beta)-tubulin genes in Neurospora crassa. Primers previously developed for the intergenic transcribed spacer region of the ribosomal DNA were also used. The degree of interspecific polymorphism observed in the PCR products from the six Fusarium species allowed differentiation by a limited number of amplifications and restriction endonuclease digestions. The level of intraspecific RFLP variation in the five PCR products was low in both Fusarium proliferatum and F. avenaceum but was high in a population sample of F. oxysporum isolates. Clustering of the 35 isolates by statistical analyses gave similar dendrograms for H3, H4, and (beta)-tubulin RFLP analysis, but a dendrogram produced by intergenic transcribed spacer analysis varied in the placement of some F. oxysporum isolates. PMID:16534991

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

    DOE PAGES

    Gacura, Matthew D.; Sprockett, Daniel D.; Heidenreich, Bess; ...

    2016-02-17

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

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

    SciTech Connect

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

    2016-02-17

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

  12. A new proteinaceous pathogen-associated molecular pattern (PAMP) identified in Ascomycete fungi induces cell death in Solanaceae.

    PubMed

    Franco-Orozco, Barbara; Berepiki, Adokiye; Ruiz, Olaya; Gamble, Louise; Griffe, Lucie L; Wang, Shumei; Birch, Paul R J; Kanyuka, Kostya; Avrova, Anna

    2017-04-07

    Pathogen-associated molecular patterns (PAMPs) are detected by plant pattern recognition receptors (PRRs), which gives rise to PAMP-triggered immunity (PTI). We characterized a novel fungal PAMP, Cell Death Inducing 1 (RcCDI1), identified in the Rhynchosporium commune transcriptome sampled at an early stage of barley (Hordeum vulgare) infection. The ability of RcCDI1 and its homologues from different fungal species to induce cell death in Nicotiana benthamiana was tested following agroinfiltration or infiltration of recombinant proteins produced by Pichia pastoris. Virus-induced gene silencing (VIGS) and transient expression of Phytophthora infestans effectors PiAVR3a and PexRD2 were used to assess the involvement of known components of PTI in N. benthamiana responses to RcCDI1. RcCDI1 was highly upregulated early during barley colonization with R. commune. RcCDI1 and its homologues from different fungal species, including Zymoseptoria tritici, Magnaporthe oryzae and Neurospora crassa, exhibited PAMP activity, inducing cell death in Solanaceae but not in other families of dicots or monocots. RcCDI1-triggered cell death was shown to require N. benthamiana Brassinosteroid insensitive 1-Associated Kinase 1 (NbBAK1), N. benthamiana suppressor of BIR1-1 (NbSOBIR1) and N. benthamiana SGT1 (NbSGT1), but was not suppressed by PiAVR3a or PexRD2. We report the identification of a novel Ascomycete PAMP, RcCDI1, recognized by Solanaceae but not by monocots, which activates cell death through a pathway that is distinct from that triggered by the oomycete PAMP INF1.

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

    PubMed Central

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

    2014-01-01

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

  14. 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

  15. Molecular Genetics of Mating Recognition in Basidiomycete Fungi

    PubMed Central

    Casselton, Lorna A.; Olesnicky, Natalie S.

    1998-01-01

    The recognition of compatible mating partners in the basidiomycete fungi requires the coordinated activities of two gene complexes defined as the mating-type genes. One complex encodes members of the homeobox family of transcription factors, which heterodimerize on mating to generate an active transcription regulator. The other complex encodes peptide pheromones and 7-transmembrane receptors that permit intercellular signalling. Remarkably, a single species may have many thousands of cross-compatible mating types because the mating-type genes are multiallelic. Different alleles of both sets of genes are necessary for mating compatibility, and they trigger the initial stages of sexual development—the formation of a specialized filamentous mycelium termed the dikaryon, in which the haploid nuclei remain closely associated in each cell but do not fuse. Three species have been taken as models to describe the molecular structure and organization of the mating-type loci and the genes sequestered within them: the pathogenic smut fungus Ustilago maydis and the mushrooms Coprinus cinereus and Schizophyllum commune. Topics addressed in this review are the roles of the mating-type gene products in regulating sexual development, the molecular basis for multiple mating types, and the molecular interactions that permit different allelic products of the mating type genes to be discriminated. Attention is drawn to the remarkable conservation in the mechanisms that regulate sexual development in basidiomycetes and unicellular ascomycete yeasts, Saccharomyces cerevisiae and Schizosaccharomyces pombe, a theme which is developed in the general conclusion to include the filamentous ascomycetes Neurospora crassa and Podospora anserina. PMID:9529887

  16. 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 14Cα-palmitoyl-CoA consumption, we demonstrated that fatty acid catabolism takes place in both peroxisomal and mitochondrial subcellular fractions. We then observed that a fox2Δ null mutant was unable to catabolize fatty acids in the mitochondrial fraction, thus indicating that the mitochondrial pathway was Fox2p-dependent. This finding was confirmed by the immunodetection of Fox2p in protein extracts obtained from purified peroxisomal and mitochondrial fractions. Finally, immunoelectron microscopy provided evidence that Fox2p was localized in both peroxisomes and mitochondria. This work constitutes the first demonstration of the existence of a Fox2p-dependent mitochondrial β-oxidation pathway in an ascomycetous yeast, C. lusitaniae. It also points to the existence of an alternative fatty acid catabolism pathway, probably located in peroxisomes, and functioning in a Fox2p-independent manner. PMID:25486052

  17. Autophagy genes Smatg8 and Smatg4 are required for fruiting-body development, vegetative growth and ascospore germination in the filamentous ascomycete Sordaria macrospora

    PubMed Central

    Voigt, Oliver; Pöggeler, Stefanie

    2013-01-01

    Autophagy is a tightly controlled degradation process involved in various developmental aspects of eukaryotes. However, its involvement in developmental processes of multicellular filamentous ascomycetes is largely unknown. Here, we analyzed the impact of the autophagic proteins SmATG8 and SmATG4 on the sexual and vegetative development of the filamentous ascomycete Sordaria macrospora. A Saccharomyces cerevisiae complementation assay demonstrated that the S. macrospora Smatg8 and Smatg4 genes can functionally replace the yeast homologs. By generating homokaryotic deletion mutants, we showed that the S. macrospora SmATG8 and SmATG4 orthologs were associated with autophagy-dependent processes. Smatg8 and Smatg4 deletions abolished fruiting-body formation and impaired vegetative growth and ascospore germination, but not hyphal fusion. We demonstrated that SmATG4 was capable of processing the SmATG8 precursor. SmATG8 was localized to autophagosomes, whereas SmATG4 was distributed throughout the cytoplasm of S. macrospora. Furthermore, we could show that Smatg8 and Smatg4 are not only required for nonselective macroautophagy, but for selective macropexophagy as well. Taken together, our results suggest that in S. macrospora, autophagy seems to be an essential and constitutively active process to sustain high energy levels for filamentous growth and multicellular development even under nonstarvation conditions. PMID:23064313

  18. Autophagic kinases SmVPS34 and SmVPS15 are required for viability in the filamentous ascomycete Sordaria macrospora.

    PubMed

    Voigt, Oliver; Herzog, Britta; Jakobshagen, Antonia; Pöggeler, Stefanie

    2014-01-01

    Autophagy is a tightly controlled degradation process of all eukaryotes. It includes the sequestration of cytoplasmic contents and organelles within a double-membraned autophagosome. Autophagy involves core autophagy related (atg) genes as well as genes regulating vesicle trafficking. Previously, we analyzed the impact of proteins of the core autophagic machinery SmATG7, SmATG8 and SmATG4 on the sexual and vegetative development of the filamentous ascomycete Sordaria macrospora. While deletion of Smatg8 and Smatg4 abolished fruiting-body formation and impaired vegetative growth, Smatg7 is required for viability. In yeast, the phosphatidylinositol 3-kinase vacuolar protein sorting 34 (Vps34) and its myristoylated membrane targeting unit, the protein kinase Vps15 have been shown to be important regulators of autophagy and vacuolar protein sorting. However, their exact role in filamentous ascomycetes remains elusive. To determine the function of Smvps34 and Smvps15 we isolated genes with high sequence similarity to Saccharomyces cerevisiae VPS34 and VPS15. For both genes we were not able to generate a homokaryotic knockout mutant in S. macrospora, suggesting that Smvps34 and Smvps15 are required for viability. Furthermore, we analyzed the repertoire of vps genes encoded by S. macrospora and could identify putative homologs of nearly all of the 61 VPS genes of S. cerevisiae.

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

    PubMed Central

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

    2016-01-01

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

  20. Genetic diversity of algal and fungal partners in four species of Umbilicaria (Lichenized Ascomycetes) along a transect of the Antarctic peninsula.

    PubMed

    Romeike, J; Friedl, T; Helms, G; Ott, S

    2002-08-01

    Lichens from the genus Umbilicaria were collected across a 5,000-km transect through Antarctica and investigated for DNA sequence polymorphism in a region of 480-660 bp of the nuclear internal transcribed spacer region of ribosomal DNA. Sequences from both fungal (16 ascomycetes) and photosynthetic partners (22 chlorophytes from the genus Trebouxia) were determined and compared with homologs from lichens inhabiting more temperate, continental climates. The phylogenetic analyses reveal that Antarctic lichens have colonized their current habitats both through multiple independent colonization events from temperate embarkation zones and through recent long-range dispersal in the Antarctic of successful preexisting colonizers. Furthermore, the results suggest that relichenization-de novo establishment of the fungus-photosynthesizer symbiosis from nonlichenized algal and fungal cells-has occurred during the process of Antarctic lichen dispersal. Independent dispersal of algal and fungal cultures therefore can lead to a successful establishment of the lichen symbiosis even under harsh Antarctic conditions.

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

    PubMed Central

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

    2016-01-01

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

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

    PubMed

    Degenkolb, Thomas; Vilcinskas, Andreas

    2016-05-01

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

  3. Yamadazyma barbieri f.a. sp. nov., an ascomycetous anamorphic yeast isolated from a Mid-Atlantic Ridge hydrothermal site (-2300 m) and marine coastal waters.

    PubMed

    Burgaud, Gaëtan; Coton, Monika; Jacques, Noémie; Debaets, Stella; Maciel, Natália O P; Rosa, Carlos A; Gadanho, Mário; Sampaio, José Paulo; Casaregola, Serge

    2016-09-01

    Two yeast strains that are members of the same species were isolated from different marine habitats, i.e. one from Mid-Atlantic Ridge ocean water samples located in the direct vicinity of black smokers near the Rainbow deep-sea hydrothermal vent and one from Brazilian marine water samples off the Ipanema beach. Strains CLIB 1964T and CLIB 1965 are anamorphic ascomycetous yeasts affiliated to the Yamadazyma clade of Saccharomycetales. Interestingly, these strains were phylogenetically and distinctly positioned into a group of species comprising all species of the genus Yamadazyma isolated from marine habitats including deep-sea hydrothermal vents, i.e.Candida atmosphaerica,C. spencermartinsiae,C. atlantica,C. oceani and C. taylorii. These strains differed significantly in their D1/D2 domain sequences of the LSU rRNA gene from the closely related species mentioned above, by 2.6, 3.0, 3.4, 3.8 and 6.0 %, respectively. Internal transcribed spacer region sequence divergence was also significant and corresponded to 4.6, 4.7, 4.7, 12.0 and 24.7 % with C. atlantica,C. atmosphaerica, C. spencermartinsiae,C. oceani and C. taylorii, respectively. Phenotypically, strains CLIB 1964T and CLIB 1965 could be distinguished from closely related species by their inability to assimilate l-sorbose. CLIB 1964T (=CBS 14301T=UBOCC-A-214001T) is the designated type strain for Yamadazyma barbieri sp. nov. The MycoBank number is MB 815884.

  4. Rapid identification of ascomycetous yeasts from clinical specimens by a molecular method based on flow cytometry and comparison with identifications from phenotypic assays.

    PubMed

    Page, Brent T; Shields, Christine E; Merz, William G; Kurtzman, Cletus P

    2006-09-01

    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. Large-subunit rRNA domains 1 and 2 (D1/D2) gene sequence analysis was also performed and served as the reference for correct strain identification. A panel of 88 clinical isolates was tested that included representatives of nine commonly encountered species and six infrequently encountered species. The PA included germ tube production, fermentation of seven carbohydrates, morphology on corn meal agar, urease and phenoloxidase activities, and carbohydrate assimilation tests when needed. The FC method (Luminex) employed species-specific oligonucleotides attached to polystyrene beads, which were hybridized with D1/D2 amplicons from the unidentified isolates. The PA identified 81 of 88 strains correctly but misidentified 4 of Candida dubliniensis, 1 of C. bovina, 1 of C. palmioleophila, and 1 of C. bracarensis. The FC method correctly identified 79 of 88 strains and did not misidentify any isolate but did not identify nine isolates because oligonucleotide probes were not available in the current library. The FC assay takes approximately 5 h, whereas the PA takes from 2 h to 5 days for identification. In conclusion, PA did well with the commonly encountered species, was not accurate for uncommon species, and takes significantly longer than the FC method. These data strongly support the potential of FC technology for rapid and accurate identification of medically important yeasts. With the introduction of new antifungals, rapid, accurate identification of pathogenic yeasts is more important than ever for guiding antifungal chemotherapy.

  5. Candida alocasiicola sp. nov., Candida hainanensis sp. nov., Candida heveicola sp. nov. and Candida musiphila sp. nov., novel anamorphic, ascomycetous yeast species isolated from plants.

    PubMed

    Wang, Shi-An; Jia, Jian-Hua; Bai, Feng-Yan

    2008-08-01

    In a taxonomic study on the ascomycetous yeasts isolated from plant materials collected in tropical forests in Yunnan and Hainan Provinces, southern China, four strains isolated from tree sap (YJ2E(T)) and flowers (YF9E(T), YWZH3C(T) and YYF2A(T)) were revealed to represent four undescribed yeast species. Molecular phylogenetic analysis based on the large subunit (26S) rRNA gene D1/D2 domain sequences showed that strain YJ2E(T) was located in a clade together with Candida haemulonii and C. pseudohaemulonii. Strain YF9E(T) was most closely related to C. azyma and strain YWZH3C(T) to C. sorbophila and C. spandovensis. Strain YYF2A(T) was clustered in a clade containing small-spored Metschnikowia species and related anamorphic Candida species. The new strains differed from their closely related described species by more than 10% mismatches in the D1/D2 domain. No sexual states were observed for the four strains on various sporulation media. The new species are therefore assigned to the genus Candida and described as Candida alocasiicola sp. nov. (type strain, YF9E(T) = AS 2.3484(T) = CBS 10702(T)), Candida hainanensis sp. nov. (type strain, YYF2A(T) = AS 2.3478(T) = CBS 10696(T)), Candida heveicola sp. nov. (type strain, YJ2E(T) = AS 2.3483(T) = CBS 10701(T)) and Candida musiphila sp. nov. (type strain, YWZH3C(T) = AS 2.3479(T) = CBS 10697(T)).

  6. Transformation in fungi.

    PubMed Central

    Fincham, J R

    1989-01-01

    Transformation with exogenous deoxyribonucleic acid (DNA) now appears to be possible with all fungal species, or at least all that can be grown in culture. This field of research is at present dominated by Saccharomyces cerevisiae and two filamentous members of the class Ascomycetes, Aspergillus nidulans and Neurospora crassa, with substantial contributions also from fission yeast (Schizosaccharomyces pombe) and another filamentous member of the class Ascomycetes, Podospora anserina. However, transformation has been demonstrated, and will no doubt be extensively used, in representatives of most of the main fungal classes, including Phycomycetes, Basidiomycetes (the order Agaricales and Ustilago species), and a number of the Fungi Imperfecti. The list includes a number of plant pathogens, and transformation is likely to become important in the analysis of the molecular basis of pathogenicity. Transformation may be maintained either by using an autonomously replicating plasmid as a vehicle for the transforming DNA or through integration of the DNA into the chromosomes. In S. cerevisiae and other yeasts, a variety of autonomously replicating plasmids have been used successfully, some of them designed for use as shuttle vectors for Escherichia coli as well as for yeast transformation. Suitable plasmids are not yet available for use in filamentous fungi, in which stable transformation is dependent on chromosomal integration. In Saccharomyces cerevisiae, integration of transforming DNA is virtually always by homology; in filamentous fungi, in contrast, it occurs just as frequently at nonhomologous (ectopic) chromosomal sites. The main importance of transformation in fungi at present is in connection with gene cloning and the analysis of gene function. The most advanced work is being done with S. cerevisiae, in which the virtual restriction of stable DNA integration to homologous chromosome loci enables gene disruption and gene replacement to be carried out with greater

  7. Horizontal transfer of a large and highly toxic secondary metabolic gene cluster between fungi.

    PubMed

    Slot, Jason C; Rokas, Antonis

    2011-01-25

    Genes involved in intermediary and secondary metabolism in fungi are frequently physically linked or clustered. For example, in Aspergillus nidulans the entire pathway for the production of sterigmatocystin (ST), a highly toxic secondary metabolite and a precursor to the aflatoxins (AF), is located in a ∼54 kb, 23 gene cluster. We discovered that a complete ST gene cluster in Podospora anserina was horizontally transferred from Aspergillus. Phylogenetic analysis shows that most Podospora cluster genes are adjacent to or nested within Aspergillus cluster genes, although the two genera belong to different taxonomic classes. Furthermore, the Podospora cluster is highly conserved in content, sequence, and microsynteny with the Aspergillus ST/AF clusters and its intergenic regions contain 14 putative binding sites for AflR, the transcription factor required for activation of the ST/AF biosynthetic genes. Examination of ∼52,000 Podospora expressed sequence tags identified transcripts for 14 genes in the cluster, with several expressed at multiple life cycle stages. The presence of putative AflR-binding sites and the expression evidence for several cluster genes, coupled with the recent independent discovery of ST production in Podospora [1], suggest that this HGT event probably resulted in a functional cluster. Given the abundance of metabolic gene clusters in fungi, our finding that one of the largest known metabolic gene clusters moved intact between species suggests that such transfers might have significantly contributed to fungal metabolic diversity. PAPERFLICK:

  8. 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.

  9. Prions are affected by evolution at two levels.

    PubMed

    Wickner, Reed B; Kelly, Amy C

    2016-03-01

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

  10. Yeast prions: evolution of the prion concept.

    PubMed

    Wickner, Reed B; Edskes, Herman K; Shewmaker, Frank; Nakayashiki, Toru; Engel, Abbi; McCann, Linsay; Kryndushkin, Dmitry

    2007-01-01

    Prions (infectious proteins) analogous to the scrapie agent have been identified in Saccharomyces cerevisiae and Podospora anserina based on their special genetic characteristics. Each is a protein acting as a gene, much like nucleic acids have been shown to act as enzymes. The [URE3], [PSI(+)], [PIN(+)] and [Het-s] prions are self-propagating amyloids of Ure2p, Sup35p, Rnq1p and the HET-s protein, respectively. The [beta] and [C] prions are enzymes whose precursor activation requires their own active form. [URE3] and [PSI(+)] are clearly diseases, while [Het-s] and [beta] carry out normal cell functions. Surprisingly, the prion domains of Ure2p and Sup35p can be randomized without loss of ability to become a prion. Thus amino acid content and not sequence determine these prions. Shuffleability also suggests amyloids with a parallel in-register beta-sheet structure.

  11. The formation of bioactive amyloid species by prion proteins in vitro and in cells.

    PubMed

    Liu, Yuanbin; Ritter, Christiane; Riek, Roland; Schubert, David

    2006-10-09

    Amyloid proteins are a group of proteins that can polymerize into cross beta-sheeted amyloid species. We have found that enhancing cellular 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) formazan exocytosis is a common property of bioactive amyloid species formed from all of the amyloid proteins tested to date. In this report, we show that the infectious amyloid species of the prion protein HET-s of the filamentous fungus Podospora anserina, like other amyloidogenic proteins, also enhances MTT formazan exocytosis. More strikingly, cellular MTT formazan exocytosis revealed the formation of bioactive amyloid species in prion-infected mouse N2a neuroblastoma cells. These findings suggest that cellular MTT formazan exocytosis can be useful for studying the roles of bioactive amyloid species in prion infectivity and prion-induced neurodegeneration.

  12. Prions are Affected by Evolution at Two Levels

    PubMed Central

    Wickner, Reed B.; Kelly, Amy C.

    2015-01-01

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

  13. Discovery of a novel superfamily of type III polyketide synthases in Aspergillus oryzae.

    PubMed

    Seshime, Yasuyo; Juvvadi, Praveen Rao; Fujii, Isao; Kitamoto, Katsuhiko

    2005-05-27

    Identification of genes encoding type III polyketide synthase (PKS) superfamily members in the industrially useful filamentous fungus, Aspergillus oryzae, revealed that their distribution is not specific to plants or bacteria. Among other Aspergilli (Aspergillus nidulans and Aspergillus fumigatus), A. oryzae was unique in possessing four chalcone synthase (CHS)-like genes (csyA, csyB, csyC, and csyD). Expression of csyA, csyB, and csyD genes was confirmed by RT-PCR. Comparative genome analyses revealed single putative type III PKS in Neurospora crassa and Fusarium graminearum, two each in Magnaporthe grisea and Podospora anserina, and three in Phenarocheate chrysosporium, with a phylogenic distinction from bacteria and plants. Conservation of catalytic residues in the CHSs across species implicated enzymatically active nature of these newly discovered homologs.

  14. A non Q/N-rich prion domain of a foreign prion, [Het-s], can propagate as a prion in yeast

    PubMed Central

    Taneja, Vibha; Maddelein, Marie-Lise; Talarek, Nicolas; J. Saupe, Sven; Liebman, Susan W.

    2007-01-01

    Summary Prions are self-propagating, infectious aggregates of misfolded proteins. The mammalian prion, PrPSc, causes fatal neurodegenerative disorders. Fungi also have prions. While yeast prions depend upon glutamine/asparagine(Q/N)-rich regions, the Podospora anserina HET-s and PrP prion proteins, lack such sequences. Nonetheless, we show that the HET-s prion domain fused to GFP propagates as a prion in yeast. Analogously to native yeast prions: transient overexpression of the HET-s fusion induces ring-like aggregates that propagate in daughter cells as cytoplasmically-inherited, detergent-resistant dot aggregates. Efficient dot propagation, but not ring formation, is dependent upon the Hsp104 chaperone. The yeast prion [PIN+] enhances HET-s ring formation, suggesting that prions with and without Q/N-rich regions interact. Finally, HET-s aggregates propagated in yeast are infectious when introduced into Podospora. To our knowledge, this is the first report of prion propagation in a truly foreign host. Since yeast can host non Q/N-rich prions, such native yeast prions may exist. PMID:17612491

  15. Reverse transcriptase activity of an intron encoded polypeptide.

    PubMed Central

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

    1994-01-01

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

  16. A Differential Genome-Wide Transcriptome Analysis: Impact of Cellular Copper on Complex Biological Processes like Aging and Development

    PubMed Central

    Servos, Jörg; Hamann, Andrea; Grimm, Carolin; Osiewacz, Heinz D.

    2012-01-01

    The regulation of cellular copper homeostasis is crucial in biology. Impairments lead to severe dysfunctions and are known to affect aging and development. Previously, a loss-of-function mutation in the gene encoding the copper-sensing and copper-regulated transcription factor GRISEA of the filamentous fungus Podospora anserina was reported to lead to cellular copper depletion and a pleiotropic phenotype with hypopigmentation of the mycelium and the ascospores, affected fertility and increased lifespan by approximately 60% when compared to the wild type. This phenotype is linked to a switch from a copper-dependent standard to an alternative respiration leading to both a reduced generation of reactive oxygen species (ROS) and of adenosine triphosphate (ATP). We performed a genome-wide comparative transcriptome analysis of a wild-type strain and the copper-depleted grisea mutant. We unambiguously assigned 9,700 sequences of the transcriptome in both strains to the more than 10,600 predicted and annotated open reading frames of the P. anserina genome indicating 90% coverage of the transcriptome. 4,752 of the transcripts differed significantly in abundance with 1,156 transcripts differing at least 3-fold. Selected genes were investigated by qRT-PCR analyses. Apart from this general characterization we analyzed the data with special emphasis on molecular pathways related to the grisea mutation taking advantage of the available complete genomic sequence of P. anserina. This analysis verified but also corrected conclusions from earlier data obtained by single gene analysis, identified new candidates of factors as part of the cellular copper homeostasis system including target genes of transcription factor GRISEA, and provides a rich reference source of quantitative data for further in detail investigations. Overall, the present study demonstrates the importance of systems biology approaches also in cases were mutations in single genes are analyzed to explain the

  17. Effect of paraquat-induced oxidative stress

    PubMed Central

    Wiemer, Matthias; Osiewacz, Heinz D.

    2014-01-01

    Aging of biological systems is influenced by various factors, conditions and processes. Among others, processes allowing organisms to deal with various types of stress are of key importance. In particular, oxidative stress as the result of the generation of reactive oxygen species (ROS) at the mitochondrial respiratory chain and the accumulation of ROS-induced molecular damage has been strongly linked to aging. Here we view the impact of ROS from a different angle: their role in the control of gene expression. We report a genome-wide transcriptome analysis of the fungal aging model Podospora anserina grown on medium containing paraquat (PQ). This treatment leads to an increased cellular generation and release of H2O2, a reduced growth rate, and a decrease in lifespan. The combined challenge by PQ and copper has a synergistic negative effect on growth and lifespan. The data from the transcriptome analysis of the wild type cultivated under PQ-stress and their comparison to those of a longitudinal aging study as well as of a copper-uptake longevity mutant of P. anserina revealed that PQ-stress leads to the up-regulation of transcripts coding for components involved in mitochondrial remodeling. PQ also affects the expression of copper-regulated genes suggesting an increase of cytoplasmic copper levels as it has been demonstrated earlier to occur during aging of P. anserina and during senescence of human fibroblasts. This effect may result from the induction of the mitochondrial permeability transition pore via PQ-induced ROS, leading to programmed cell death as part of an evolutionary conserved mechanism involved in biological aging and lifespan control. PMID:28357247

  18. Vanderwaltozyma verrucispora sp. nov., a new ascomycetous yeast species.

    PubMed

    Lee, Ching-Fu; Liu, Chun-Hao; Ninomiya, Shinya; Kawasaki, Hiroko; Nakase, Takashi

    2009-02-01

    A new yeast species, Vanderwaltozyma verrucispora, is proposed in this study based on two strains isolated from partially decayed leaves in Japan and one strain from soil in Taiwan. The species is characterized by the fermentation of glucose and galactose, formation of one to four spheroidal to ellipsoidal ascospores with warty surfaces in each ascus, and assimilation of a few carbon and nitrogen compounds. Genus assignment and distinction of the species from the other two recognized species of Vanderwaltozyma is based on the morphological and physiological characteristics, and phylogenetic analysis of nucleotide sequences of the D1/D2 domains of the large subunit (LSU) rRNA gene. From these comparisons, the name V. verrucispora sp. nov. is proposed. Sequence analysis of the D1/D2 domains of the LSU rRNA gene reveals that the phylogenetically closest relative of V. verrucispora is Vanderwaltozyma yarrowii. The type strain of the new species, which was isolated from a partially decayed leaf in Kagoshima Prefecture, Japan, is NBRC 1884(T) (=CBS 10887(T)=BCRC 23141(T)).

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

    PubMed Central

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

    1995-01-01

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

  20. Interaction of Prions Causes Heritable Traits in Saccharomyces cerevisiae.

    PubMed

    Nizhnikov, Anton A; Ryzhova, Tatyana A; Volkov, Kirill V; Zadorsky, Sergey P; Sopova, Julia V; Inge-Vechtomov, Sergey G; Galkin, Alexey P

    2016-12-01

    The concept of "protein-based inheritance" defines prions as epigenetic determinants that cause several heritable traits in eukaryotic microorganisms, such as Saccharomyces cerevisiae and Podospora anserina. Previously, we discovered a non-chromosomal factor, [NSI+], which possesses the main features of yeast prions, including cytoplasmic infectivity, reversible curability, dominance, and non-Mendelian inheritance in meiosis. This factor causes omnipotent suppression of nonsense mutations in strains of S. cerevisiae bearing a deleted or modified Sup35 N-terminal domain. In this work, we identified protein determinants of [NSI+] using an original method of proteomic screening for prions. The suppression of nonsense mutations in [NSI+] strains is determined by the interaction between [SWI+] and [PIN+] prions. Using genetic and biochemical methods, we showed that [SWI+] is the key determinant of this nonsense suppression, whereas [PIN+] does not cause nonsense suppression by itself but strongly enhances the effect of [SWI+]. We demonstrated that interaction of [SWI+] and [PIN+] causes inactivation of SUP45 gene that leads to nonsense suppression. Our data show that prion interactions may cause heritable traits in Saccharomyces cerevisiae.

  1. 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

  2. The mitochondrial genome of the entomopathogenic fungus Beauveria bassiana: analysis of the ribosomal RNA region.

    PubMed

    Pfeifer, T A; Hegedus, D D; Khachatourians, G G

    1993-01-01

    The 28.5-kbp mitochondrial (mt) genome from the entomopathogenic fungus Beauveria bassiana was studied using restriction enzyme analysis, gene probe hybridization, and DNA sequence comparisons. A detailed restriction enzyme map allowed cloning of the entire genome into a number of segments. Hybridization of heterologous gene probes to the mtDNA resulted in the identification of the large ribosomal RNA (lrRNA) and small ribosomal RNA (srRNA) genes. Gene probes derived from several yeasts and fungi failed to identify any additional genes. However, partial DNA sequence analysis revealed the lrRNA and srRNA genes as well as four protein-encoding genes: the NADH dehydrogenase subunit 1 (NAD1), NADH dehydrogenase subunit 6 (NAD6), cytochrome oxidase subunit 3 (CO3), and ATPase subunit 6 (ATP6) genes. The ATPase subunit 9 (ATP9) gene was not identified by hybridization to mtDNA, but could be detected by hybridization to total cellular DNA. The portions of the genes sequenced were homologous to the equivalent genes from yeast and other filamentous fungi, most notably Aspergillus nidulans. No introns were identified in these regions. The organization of the sequenced region of the B. bassiana mt genome more closely resembled that of A. nidulans than that of Podospora anserina or Neurospora crassa.

  3. Yeast and Fungal Prions: Amyloid-Handling Systems, Amyloid Structure, and Prion Biology.

    PubMed

    Wickner, R B; Edskes, H K; Gorkovskiy, A; Bezsonov, E E; Stroobant, E E

    2016-01-01

    Yeast prions (infectious proteins) were discovered by their outré genetic properties and have become important models for an array of human prion and amyloid diseases. A single prion protein can become any of many distinct amyloid forms (called prion variants or strains), each of which is self-propagating, but with different biological properties (eg, lethal vs mild). The folded in-register parallel β sheet architecture of the yeast prion amyloids naturally suggests a mechanism by which prion variant information can be faithfully transmitted for many generations. The yeast prions rely on cellular chaperones for their propagation, but can be cured by various chaperone imbalances. The Btn2/Cur1 system normally cures most variants of the [URE3] prion that arise. Although most variants of the [PSI+] and [URE3] prions are toxic or lethal, some are mild in their effects. Even the most mild forms of these prions are rare in the wild, indicating that they too are detrimental to yeast. The beneficial [Het-s] prion of Podospora anserina poses an important contrast in its structure, biology, and evolution to the yeast prions characterized thus far.

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

    PubMed

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

    2015-01-01

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

  5. 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

  6. Interaction of Prions Causes Heritable Traits in Saccharomyces cerevisiae

    PubMed Central

    Ryzhova, Tatyana A.; Inge-Vechtomov, Sergey G.; Galkin, Alexey P.

    2016-01-01

    The concept of "protein-based inheritance" defines prions as epigenetic determinants that cause several heritable traits in eukaryotic microorganisms, such as Saccharomyces cerevisiae and Podospora anserina. Previously, we discovered a non-chromosomal factor, [NSI+], which possesses the main features of yeast prions, including cytoplasmic infectivity, reversible curability, dominance, and non-Mendelian inheritance in meiosis. This factor causes omnipotent suppression of nonsense mutations in strains of S. cerevisiae bearing a deleted or modified Sup35 N-terminal domain. In this work, we identified protein determinants of [NSI+] using an original method of proteomic screening for prions. The suppression of nonsense mutations in [NSI+] strains is determined by the interaction between [SWI+] and [PIN+] prions. Using genetic and biochemical methods, we showed that [SWI+] is the key determinant of this nonsense suppression, whereas [PIN+] does not cause nonsense suppression by itself but strongly enhances the effect of [SWI+]. We demonstrated that interaction of [SWI+] and [PIN+] causes inactivation of SUP45 gene that leads to nonsense suppression. Our data show that prion interactions may cause heritable traits in Saccharomyces cerevisiae. PMID:28027291

  7. Biotransformation of Trichoderma spp. and their tolerance to aromatic amines, a major class of pollutants.

    PubMed

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

    2013-08-01

    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.

  8. 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

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

    PubMed Central

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

    2011-01-01

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

  10. The crystal structure of an extracellular catechol oxidase from the ascomycete fungus Aspergillus oryzae.

    PubMed

    Hakulinen, Nina; Gasparetti, Chiara; Kaljunen, Heidi; Kruus, Kristiina; Rouvinen, Juha

    2013-12-01

    Catechol oxidases (EC 1.10.3.1) catalyse the oxidation of o-diphenols to their corresponding o-quinones. These oxidases contain two copper ions (CuA and CuB) within the so-called coupled type 3 copper site as found in tyrosinases (EC 1.14.18.1) and haemocyanins. The crystal structures of a limited number of bacterial and fungal tyrosinases and plant catechol oxidases have been solved. In this study, we present the first crystal structure of a fungal catechol oxidase from Aspergillus oryzae (AoCO4) at 2.5-Å resolution. AoCO4 belongs to the newly discovered family of short-tyrosinases, which are distinct from other tyrosinases and catechol oxidases because of their lack of the conserved C-terminal domain and differences in the histidine pattern for CuA. The sequence identity of AoCO4 with other structurally known enzymes is low (less than 30 %), and the crystal structure of AoCO4 diverges from that of enzymes belonging to the conventional tyrosinase family in several ways, particularly around the central α-helical core region. A diatomic oxygen moiety was identified as a bridging molecule between the two copper ions CuA and CuB separated by a distance of 4.2-4.3 Å. The UV/vis absorption spectrum of AoCO4 exhibits a distinct maximum of absorbance at 350 nm, which has been reported to be typical of the oxy form of type 3 copper enzymes.

  11. 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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  13. Slippery when wet: phylogeny and character evolution in the gelatinous cyanobacterial lichens (Peltigerales, Ascomycetes).

    PubMed

    Wedin, Mats; Wiklund, Elisabeth; Jørgensen, Per Magnus; Ekman, Stefan

    2009-12-01

    Many lichen fungi form symbioses with filamentous Nostoc cyanobacteria, which cause the lichen to swell and become extremely gelatinous when moist. Within the Lecanoromycetes, such gelatinous lichens are today mainly classified in the Collemataceae (Peltigerales, Ascomycota). We performed Bayesian MCMC, maximum likelihood, and maximum parsimony analyses of three independent markers (mtSSU rDNA, nuLSU rDNA, and RPB1), to improve our understanding of the phylogeny and classification in the Peltigerales, as well as the evolution of morphological characters that have been used for classification purposes in this group. The Collemataceae and the non-gelatinous Pannariaceae are paraphyletic but can be re-circumscribed as monophyletic if Leciophysma, Physma, Ramalodium and Staurolemma are transferred to the Pannariaceae. The gelatinous taxa transferred to the Pannariaceae deviate from other Collemataceae in having simple ascospores, and several also have a ring-shaped exciple as in other Pannariaceae, rather than the disc-shaped exciple found in the typical Collemataceae. Both Collema and Leptogium are non-monophyletic. The re-circumscribed Collemataceae shares a distinct ascus type with the sister group Placynthiaceae and the Coccocarpiaceae, whereas Pannariaceae includes a variety of structures. All Pannariaceae have one-celled ascospores, whereas all Collemataceae have two- or multi-celled spores. Reconstructions of the number of character state transformations in exciple structure, thallus gelatinosity, and ascus apex structure indicate that the number of transformations is distinctly higher than the minimum possible. Most state transformations in the exciple took place from a ring-shaped to a disc-shaped exciple. Depending on the reconstruction method, most or all transformations in thallus structure took place from a non-gelatinous to a gelatinous thallus. Gains and losses of internal structures in the ascus apex account for all or a vast majority of the number of transformations in the ascus, whereas direct transformations between asci with internal structures appear to have been rare.

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

    PubMed

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

    2015-09-01

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

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

    PubMed

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

    2009-12-01

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

  16. 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...

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

    PubMed

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

    2007-06-01

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

  18. Candida ecuadorensis sp. nov., an ascomycetous yeast species found in two separate regions of Ecuador.

    PubMed

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

    2013-01-01

    In the course of an on-going study aimed at cataloguing the natural yeast biodiversity found in Ecuador, two strains (CLQCA 13-025 and CLQCA 20-004(T)) were isolated from samples of cow manure and rotten wood collected in two separate provinces of the country (Orellana and Bolívar). These strains were found to represent a novel yeast species based on the sequences of their D1/D2 domain of the large-subunit (LSU) rRNA gene and their physiological characteristics. Phylogenetic analysis based on LSU D1/D2 sequences revealed this novel species to belong to the Metschnikowia clade and to be most closely related to Candida suratensis, a species recently discovered in a mangrove forest in Thailand. The species name of Candida ecuadorensis sp. nov. is proposed to accommodate these strains, with strain CLQCA 20-004(T) (=CBS 12653(T) = NCYC 3782(T)) designated as the type strain.

  19. Remispora spitsbergenensis sp. nov., a marine lignicolous ascomycete from Svalbard, Norway.

    PubMed

    Pang, Ka-Lai; Chiang, Michael W L; Vrijmoed, Lilian L P

    2009-01-01

    Abstract: Remispora was established for R. maritima, a fungus with globose/subglobose, lightly colored and coriaceous ascomata; deliquescing asci; ellipsoidal ascospores; and bipolar, pleomorphic ascospore appendages. Seven species currently are included in Remispora: R crispa, R. galerita, R maritima, R. minuta, R. pilleata, R. quadriremis and R stellata. Variations on ascospore appendages can be observed in Remispora. In general the appendage is exosporic in nature and comprises an amorphous, electron-transparent matrix, and a fibrous, electron-dense component. An eighth Remispora species, R. spitsbergenensis sp. nov., is described here, discovered from washed-up wood collected at the shore of Longyearbyen, Svalbard, Norway. Ascospore appendages of R. spitsbergenensis appear as fibrous strands and amorphic material under the scanning electron microscope, which are characteristic of a Remispora species. Remispora spitsbergenensis resembles R. quadriremis and R. stellata because all possess four or more ascospore appendages at one end. Remispora spitsbergenensis possesses consistently four polar appendages at each end in contrast to six in R. stellata. Also ascospore appendages of R. spitsbergenensis are ribbon-like, compared with the obclavate, curved and attenuate appendages in R. quadriremis and R. stellata. A key for the identification of the eight Remispora species is provided.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  1. Differential roles of pyruvate decarboxylase in aerial and embedded mycelia of the ascomycete Gibberella zeae.

    PubMed

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

    2012-04-01

    The pyruvate-acetaldehyde-acetate (PAA) pathway has diverse roles in eukaryotes. Our previous study on acetyl-coenzyme A synthetase 1 (ACS1) in Gibberella zeae suggested that the PAA pathway is important for lipid production, which is required for perithecia maturation. In this study, we deleted all three pyruvate decarboxylase (PDC) genes, which encode enzymes that function upstream of ACS1 in the PAA pathway. Results suggest PDC1 is required for lipid accumulation in the aerial mycelia, and deletion of PDC1 resulted in highly wettable mycelia. However, the total amount of lipids in the PDC1 deletion mutants was similar to that of the wild-type strain, likely due to compensatory lipid production processes in the embedded mycelia. PDC1 was expressed both in the aerial and embedded mycelia, whereas ACS1 was observed only in the aerial mycelia in a PDC1-dependent manner. PDC1 is also involved in vegetative growth of embedded mycelia in G. zeae, possibly through initiating the ethanol fermentation pathway. Thus, PDC1 may function as a key metabolic enzyme crucial for lipid production in the aerial mycelia, but play a different role in the embedded mycelia, where it might be involved in energy generation by ethanol fermentation.

  2. Taxonomical Establishment and Compositional Studies of a New Cordyceps (Ascomycetes) Species from the Northwest Himalayas (India).

    PubMed

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

    2016-01-01

    During a frequent survey in the northwest Indian Himalayan region, a new species-Cordyceps macleodganensis-was encountered. This species is described on the basis of its macromorphological features, microscopic details, and internal transcribed spacer sequencing. This species showed only 90% resemblance to Cordyceps gracilis. The chemical composition of the mycelium showed protein (14.95 ± 0.2%) and carbohydrates (59.21 ± 3.8%) as the major nutrients. This species showed appreciable amounts of P-carotene, lycopene, phenolic compounds, polysaccharides, and flavonoids. Mycelial culture of this species showed higher effectiveness for ferric-reducing antioxidant power, DPPH radical scavenging activity, ferrous ion-chelating activity, and scavenging ability on superoxide anion-derived radicals, calculated by half-maximal effective concentrations.

  3. Effect of Polysaccharide from Cordyceps militaris (Ascomycetes) on Physical Fatigue Induced by Forced Swimming.

    PubMed

    Xu, Yan-Feng

    2016-01-01

    Cordyceps militaris is the one of the most important medicinal mushrooms, widely used in East Asian countries. Polysaccharide is considered to be the principal active component in C. militaris and has a wide range of biological and pharmacological properties. This study was undertaken to investigate the effect of polysaccharide from C. militaris (PCM) on physical fatigue induced in animals through a forced swimming test. The mice were divided into 4 groups receiving 28 days' treatment with drinking water (exercise control) or low-, medium-, and high-dose PCM (40, 80, and 160 mg/kg/day, respectively). After 28 days, the mice were subjected to the forced swimming test; the exhaustive swimming time was measured and fatigue-related biochemical parameters, including serum lactic acid, urea nitrogen, creatine kinase, alanine aminotransferase, aspartate aminotransferase, superoxide dismutase, glutathi- one peroxidase, catalase, malondialdehyde, liver glycogen, and muscle glycogen, were analyzed. The results showed that PCM could significantly prolong the exhaustive swimming time of mice; decrease concentrations of serum lactic acid, urea nitrogen, creatine kinase, aspartate aminotransferase, alanine aminotransferase, and malondialdehyde; and increase liver and muscle glycogen contents and the concentrations of serum superoxide dismutase, glutathione per- oxidase, and catalase. The data suggest that PCM has an antifatigue effect, and it might become a new functional food or medicine for fatigue resistance.

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

    PubMed

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

    2011-01-01

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

  6. Candida carvajalis sp. nov., an ascomycetous yeast species from the Ecuadorian Amazon jungle.

    PubMed

    James, Stephen A; Carvajal Barriga, Enrique Javier; Bond, Christopher J; Cross, Kathryn; Núñez, Norma C; Portero, Patricia B; Roberts, Ian N

    2009-08-01

    In the course of a yeast biodiversity survey of different ecological habitats found in Ecuador, two yeast strains (CLQCA 20-011(T) and CLQCA20-014) were isolated from samples of rotten wood and fallen leaf debris collected at separate sites in the central region of the Ecuadorian Amazonia. These strains were found to represent a novel yeast species based on the sequences of their D1/D2 domain of the large-subunit (LSU) rRNA gene and their physiological characteristics. Phylogenetic analysis based on LSU D1/D2 sequences revealed this novel species to be most closely related to Candida asparagi, Candida fructus, Candida musae and two as yet undescribed Candida species, with the six yeast taxa collectively forming a distinct species group within the Clavispora clade. The species name of Candida carvajalis sp. nov. is proposed to accommodate these strains, with CLQCA 20-011(T) (NCYC 3509(T), CBS 11361(T)) designated as the type strain.

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

    PubMed Central

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

    2011-01-01

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

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

    PubMed Central

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

    2015-01-01

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

  9. The copper transport-associated protein Ctr4 can form prion-like epigenetic determinants in Schizosaccharomyces pombe

    PubMed Central

    Sideri, Theodora; Yashiroda, Yoko; Ellis, David A.; Rodríguez-López, María; Yoshida, Minoru; Tuite, Mick F.; Bähler, Jürg

    2017-01-01

    Prions are protein-based infectious entities associated with fatal brain diseases in animals, but also modify a range of host-cell phenotypes in the budding yeast, Saccharomyces cerevisiae. Many questions remain about the evolution and biology of prions. Although several functionally distinct prion-forming proteins exist in S. cerevisiae, [HET-s] of Podospora anserina is the only other known fungal prion. Here we investigated prion-like, protein-based epigenetic transmission in the fission yeast Schizosaccharomyces pombe. We show that S. pombe cells can support the formation and maintenance of the prion form of the S. cerevisiae Sup35 translation factor [PSI+], and that the formation and propagation of these Sup35 aggregates is inhibited by guanidine hydrochloride, indicating commonalities in prion propagation machineries in these evolutionary diverged yeasts. A proteome-wide screen identified the Ctr4 copper transporter subunit as a putative prion with a predicted prion-like domain. Overexpression of the ctr4 gene resulted in large Ctr4 protein aggregates that were both detergent and proteinase-K resistant. Cells carrying such [CTR+] aggregates showed increased sensitivity to oxidative stress, and this phenotype could be transmitted to aggregate-free [ctr-] cells by transformation with [CTR+] cell extracts. Moreover, this [CTR+] phenotype was inherited in a non-Mendelian manner following mating with naïve [ctr-] cells, but intriguingly the [CTR+] phenotype was not eliminated by guanidine-hydrochloride treatment. Thus, Ctr4 exhibits multiple features diagnostic of other fungal prions and is the first example of a prion in fission yeast. These findings suggest that transmissible protein-based determinants of traits may be more widespread among fungi. PMID:28191457

  10. Autophagy provides nutrients for nonassimilating fungal structures and is necessary for plant colonization but not for infection in the necrotrophic plant pathogen Fusarium graminearum.

    PubMed

    Josefsen, Lone; Droce, Aida; Sondergaard, Teis Esben; Sørensen, Jens Laurids; Bormann, Jörg; Schäfer, Wilhelm; Giese, Henriette; Olsson, Stefan

    2012-03-01

    The role of autophagy in necrotrophic fungal physiology and infection biology is poorly understood. We have studied autophagy in the necrotrophic plant pathogen Fusarium graminearum in relation to development of nonassimilating structures and infection. We identified an ATG8 homolog F. graminearum ATG8 whose first 116 amino acids before the predicted ATG4 cleavage site are 100% identical to Podospora anserina ATG8. We generated a ΔFgatg8 mutant by gene replacement and showed that this cannot form autophagic compartments. The strain forms no perithecia, has reduced conidia production and the aerial mycelium collapses after a few days in culture. The collapsing aerial mycelium contains lipid droplets indicative of nitrogen starvation and/or an inability to use storage lipids. The capacity to use carbon/energy stored in lipid droplets after a shift from carbon rich conditions to carbon starvation is severely inhibited in the ΔFgatg8 strain demonstrating autophagy-dependent lipid utilization, lipophagy, in fungi. Radial growth rate of the ΔFgatg8 strain is reduced compared with the wild type and the mutant does not grow over inert plastic surfaces in contrast to the wild type. The ability to infect barley and wheat is normal but the mutant is unable to spread from spikelet to spikelet in wheat. Complementation by inserting the F. graminearum atg8 gene into a region adjacent to the actin gene in ΔFgatg8 fully restores the WT phenotype. The results showed that autophagy plays a pivotal role for supplying nutrients to nonassimilating structures necessary for growth and is important for plant colonization. This also indicates that autophagy is a central mechanism for fungal adaptation to nonoptimal C/N ratios.

  11. Mass analysis by scanning transmission electron microscopy and electron diffraction validate predictions of stacked beta-solenoid model of HET-s prion fibrils.

    PubMed

    Sen, Anindito; Baxa, Ulrich; Simon, Martha N; Wall, Joseph S; Sabate, Raimon; Saupe, Sven J; Steven, Alasdair C

    2007-02-23

    Fungal prions are infectious filamentous polymers of proteins that are soluble in uninfected cells. In its prion form, the HET-s protein of Podospora anserina participates in a fungal self/non-self recognition phenomenon called heterokaryon incompatibility. Like other prion proteins, HET-s has a so-called "prion domain" (its C-terminal region, HET-s-(218-289)) that is responsible for induction and propagation of the prion in vivo and for fibril formation in vitro. Prion fibrils are thought to have amyloid backbones of polymerized prion domains. A relatively detailed model has been proposed for prion domain fibrils of HET-s based on a variety of experimental constraints (Ritter, C., Maddelein, M. L., Siemer, A. B., Luhrs, T., Ernst, M., Meier, B. H., Saupe, S. J., and Riek, R. (2005) Nature 435, 844-848). To test specific predictions of this model, which envisages axial stacking of beta-solenoids with two coils per subunit, we examined fibrils by electron microscopy. Electron diffraction gave a prominent meridional reflection at (0.47 nm)(-1), indicative of cross-beta structure, as predicted. STEM (scanning transmission electron microscopy) mass-per-unit-length measurements yielded 1.02 +/- 0.16 subunits per 0.94 nm, in agreement with the model prediction (1 subunit per 0.94 nm). This is half the packing density of approximately 1 subunit per 0.47 nm previously obtained for fibrils of the yeast prion proteins, Ure2p and Sup35p, whence it follows that the respective amyloid architectures are basically different.

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

    PubMed

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

    2014-01-01

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

  13. Antioxidant and antiradical properties of methanolic extracts from algerian wild edible desert truffles (terfezia and tirmania, ascomycetes).

    PubMed

    Gouzi, Hicham; Leboukh, Mourad; Bouchouka, Elmouloud

    2013-01-01

    Wild edible truffles (namely, Terfezia leonis, Tirmania pinoyi, and T. nivea) were commercially obtained from Southern Algeria and methanolic extracts were prepared from these truffles. Their antioxidant and antiradical properties were studied by using five analytical methods: scavenging capacity on 1,1-diphenyl-2-picrylhydrazyl (DPPH·), 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS·+), superoxide anion (O2·-) radicals, ferric reducing antioxidant power (FRAP), and ferricyanide/Prussian blue assay. Chemical constituents contributing to these activities were also investigated. T. leonis had the highest total phenolics, total carotenoids, and anthocyanin contents. At 2.6 mg/mL, scavenging effects on the DPPH· radical were 92.47%, 53.06%, and 41.34% for T. leonis, T. pinoyi, and T. nivea, respectively. T. leonis showed the most potent radical scavenging activities on DPPH·, ABTS·+, and O2·- radicals, with EC50 values of 1.08, 1.35, and 7.27 mg/mL, respectively. On the other hand, T. leonis exhibited the highest reductive capabilities. On the basis of the EC50 values, T. leonis had good antioxidant and antiradical properties. These results showed that methanolic extracts from these three truffles species had effective antioxidant and antiradical properties. Therefore, wild edible desert truffles could serve as an easily accessible item of food rich in natural antioxidants, as a possible food supplement, or even as a pharmaceutical agent.

  14. Chemical Composition and Antioxidant and Antibacterial Activities of Cultured Mycelia of Four Clavicipitaceous Mushrooms (Ascomycetes) from the Indian Himalayas.

    PubMed

    Sharma, Sapan Kumar; Gautam, Nandini

    2017-01-01

    Cultured mycelia of 4 clavicipitaceous fungi belonging to 2 genera, Cordyceps (C. gracilis, C. cicadae, C. sinclairii) and Metacordyceps (M. dhauladharensis), were analyzed for their chemical composition and antioxidant and antibacterial activities. Experiments to determine these characteristics were performed following standard methods. The fatty acid profiles of mycelia of all the species were analysed using gas chromatography. Chemical composition analysis of mycelial samples revealed carbohydrates (46.72 ± 0.7% to 63.40 ± 0.3%), protein (14.19 ± 0.2% to 26.16 ± 0.1%), crude fibers (0.93 ± 0.0% to 1.22 ± 0.0%), and ash (0.77 ± 0.0% to 0.98 ± 0.0%). The amounts of calcium and iron in mycelia were significantly higher than amounts of magnesium, copper, and manganese. The amount of β-carotene ranged from 0.67 to 1.17 μg/100 g; lycopene, from 0.30 to 0.57 μg/100 g; phenolic compounds, from 29.16 to 43.12 mg/100 g; polysaccharides, from 104 to 126 mg/g; and flavonoids, from 2.15 to 4.25 mg/g. All tested species showed significant (P ≤ 0.05) antioxidant activities measured based on half-maximal effective concentrations. C. cicadae possessed the lowest half-maximal effective concentration compared with the other species. All 4 species showed a broad spectrum of antibacterial activity against 7 tested pathogenic bacterial strains.

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

    PubMed

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

    2009-12-01

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

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

    PubMed

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

    2013-01-01

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

  17. Antioxidant Potential and DNA Damage Protection by the Slate Grey Saddle Mushroom, Helvella lacunosa (Ascomycetes), from Kashmir Himalaya (India).

    PubMed

    Shameem, Nowsheen; Kamili, Azra N; Ahmad, Mushtaq; Masoodi, F A; Parray, Javid A

    2016-01-01

    This study pertains to the radical scavenging potential of and DNA protection by Helvella lacunosa, an edible mushroom from Kashmir Himalaya (India). Different solvents, on the basis of their polarities, were used to extract all solvent-soluble bioactive compounds. Seven different antioxidant methods were also used to determine extensive radical scavenging activity. The mushroom ethanol extract and butanol extract showed effective scavenging activity of radicals at 95% and 89%, respectively. At 800 µg/mg, the ethanol extract was potent enough to protect DNA from degradation by hydroxyl radicals. It is evident from these findings that the presence of antioxidant substances signifies the use of H. lacunosa as food in the mountainous valleys of the Himalayan region.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

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

    SciTech Connect

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

    2016-05-20

    Fungi in the class Dothideomycetes often live in extreme environments or have unusual physiology. One of these, the wine cellar mold Zasmidium cellare, produces thick curtains of mycelial growth in cellars with high humidity, and its ability to metabolize volatile organic compounds including alcohols, esters and formaldehyde is thought to improve air quality. It grows slowly but appears to outcompete ordinarily faster-growing species under anaerobic conditions.Whether these abilities have affected its mitochondrial genome is not known.To fill this gap, its mitochondrial genome was assembled as part of a whole- genome shotgun-sequencing project.The circular-mapping mitochondrial genome of Z. cellare, at only 23,743 bp, is the smallest yet reported for a filamentous fungus.It contains the complete set of 14 protein-coding genes seen typically in other filamentous fungi, along with genes for large and small ribosomal RNA subunits, 25 predicted tRNA genes capable of decoding all 20 amino acids, and a single open reading frame potentially coding for a protein of unknown function.The Z. cellare mitochondrial genome had genes encoded on both strands with a single change of direction, different from most other fungi but consistent with the Dothideomycetes. The high synteny among mitochondrial genomes of fungi in the Eurotiomycetes broke down almost completely in the Dothideomycetes.Only a low level of microsynteny was observed among protein-coding and tRNA genes in comparison with Mycosphaerella graminicola (synonym Zymoseptoria tritici), the only other fungus in the order Capnodiales with a sequenced mitochondrial genome, involving the three gene pairs atp8-atp9, nad2-nad3, and nad4L-nad5.However, even this low level of microsynteny did not extend to other fungi in the Dothideomycetes and Eurotiomycetes. Phylogenetic analysis of concatenated protein-coding genes confirmed the relationship between Z. cellare and M. graminicola in the Capnodiales, although conclusions were limited due to low sampling density.Other than its small size, the only unusual feature of the Z. cellare mitochondrial genome was two copies of a 110-bp sequence that were duplicated, inverted and separated by approximately 1 kb. This inverted-repeat sequence confused the assembly program but appears to have no functional significance.The small size of the Z. cellare mitochondrial genome was due to slightly smaller genes, lack of introns and non-essential genes, reduced intergenic spaces and very few ORFs relative to other fungi rather than a loss of essential genes. Whether this reduction facilitates its unusual biology remains unknown.

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

    PubMed

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

    2014-11-01

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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  2. A Novel Technique for Rejuvenation of Degenerated Caterpillar Medicinal Mushroom, Cordyceps militaris (Ascomycetes), a Valued Traditional Chinese Medicine.

    PubMed

    Chen, Anhui; Wang, Yulong; Shao, Ying; Huang, Bo

    2017-01-01

    Cordyceps militaris has been used in traditional Chinese medicine for many years, but its frequent degeneration during continuous maintenance in culture can lead to substantial commercial losses. In this study, a degenerated strain of C. militaris was obtained by subculturing a wild-type strain through 10 successive subcultures. The relative abundance of the 2 mating types seems to be out of balance in the degenerated strain. By cross-mating 4 single-ascospore isolates (2 for MAT 1-1 and 2 for MAT 1-2) from the degenerated strain, we were able to restore fruiting body production to wild-type levels. The rejuvenated strain not only produced well-developed fruiting bodies but also accumulated more cordycepin and adenosine than either the original wild-type strain or the degenerated strain. These new characteristics remained stable after 4 successive transfers, which indicates that the method used to rejuvenate the degenerated strain in this study is an effective approach.

  3. Optimization of Liquid Fermentation Conditions and Protein Nutrition Evaluation of Mycelium from the Caterpillar Medicinal Mushroom, Cordyceps militaris (Ascomycetes).

    PubMed

    Gang, Jie; Liu, Han; Liu, Yanhong

    2016-01-01

    Cordyceps militaris is a well-known traditional Chinese medicinal mushroom. In this study, the mycelium of C. militaris was cultured using liquid fermentation technology and the culture medium components were optimized by the orthogonal test method. Our results showed that the optimal medium combination for the mycelium growth is 3% glucose, 3% peptone, 0.1% MgSO4, and 0.2% KH2PO4 The international general nutritional assessment method was applied to the overall evaluation of the protein nutrition value of submerged cultivated mycelium and fruit body of C. militaris. The protein contents in C. militaris mycelium and fruit body are 21.10% and 18.47%, respectively. The first limiting amino acids of C. militaris mycelium and fruit bodies are the sulfur-containing amino acids (methionine and cysteine), and the second limiting amino acid is isoleucine. The quality of amino acids from submerged cultivated mycelium and fruit body from C. militaris was also evaluated by amino acid score (AAS), chemical score (CS), essential amino acid index (EAAI), biological value (BV), nutritional index (NI), and score of ratio coefficient of amino acid (SRCAA). Our data demonstrate that AAS, CS, EAAI, BV, NI, and SRCAA scores of the submerged cultivated mycelium proteins are 62.41, 38.74, 88.37, 84.63, 18.61, and 25.57, respectively, whereas the fruit body proteins are 37.11, 34.59, 61.92, 55.79, 11.44, and 68.51, respectively. The protein content of C. militaris mycelium has higher nutrition value than that of fruit body protein, which holds the promise for future further development. Our study provides the optimal culture conditions and the essential nutritional information of medicinal species, C. militaris.

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

    PubMed

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

    2015-04-01

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

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

    PubMed

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

    2012-02-01

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

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

    PubMed

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

    2006-05-01

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

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

    PubMed Central

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

    2012-01-01

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

  8. Effects of Illumination Pattern during Cultivation of Fruiting Body and Bioactive Compound Production by the Caterpillar Medicinal Mushroom, Cordyceps militaris (Ascomycetes).

    PubMed

    Wu, Chiu-Yeh; Liang, Zeng-Chin; Tseng, Chin-Yin; Hu, Shu-Hui

    2016-01-01

    We investigated the effects of light intensity in the 3 cultivation stages separately-the mycelium colonization stage, the primordial initiation stage, and the fruiting stage (in order)-on fruiting body and bioactive compound production by Cordyceps militaris. In the mycelium colonization stage, rice substrates were incubated in a spawn running room at 23°C. During the primordial initiation stage, C. militaris was grown at 18°C and illuminated 12 hours/day. In the fruiting stage the temperature was 23°C, with illumination provided 12 hours/day. The highest fruiting body yield and biological efficiency were 4.06 g dry weight/bottle and 86.83%, respectively, under 1750 ± 250 lux during the second and third stages. The cordycepin content was highest during the second and third stages under 1250 ± 250 lux. The mannitol and polysaccharide contents were highest under 1250 ± 250 and 1750 ± 250 lux during the primordial initiation stage and the fruiting stage, respectively. Thus, with controlled lighting, C. militaris can be cultivated in rice-water medium to increase fruiting body yield and bioactive compound production.

  9. 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....

  10. Transcriptomic responses of mixed cultures of ascomycete fungi to lignocellulose using dual RNA-seq reveal inter-species antagonism and limited beneficial effects on CAZyme expression.

    PubMed

    Daly, Paul; van Munster, Jolanda M; Kokolski, Matthew; Sang, Fei; Blythe, Martin J; Malla, Sunir; Velasco de Castro Oliveira, Juliana; Goldman, Gustavo H; Archer, David B

    2016-05-02

    Gaining new knowledge through fungal monoculture responses to lignocellulose is a widely used approach that can lead to better cocktails for lignocellulose saccharification (the enzymatic release of sugars which are subsequently used to make biofuels). However, responses in lignocellulose mixed cultures are rarely studied in the same detail even though in nature fungi often degrade lignocellulose as mixed communities. Using a dual RNA-seq approach, we describe the first study of the transcriptional responses of wild-type strains of Aspergillus niger, Trichoderma reesei and Penicillium chrysogenum in two and three mixed species shake-flask cultures with wheat straw. Based on quantification of species-specific rRNA, a set of conditions was identified where mixed cultures could be sampled so as to obtain sufficient RNA-seq reads for analysis from each species. The number of differentially-expressed genes varied from a couple of thousand to fewer than one hundred. The proportion of carbohydrate active enzyme (CAZy) encoding transcripts was lower in the majority of the mixed cultures compared to the respective straw monocultures. A small subset of P. chrysogenum CAZy genes showed five to ten-fold significantly increased transcript abundance in a two-species mixed culture with T. reesei. However, a substantial number of T. reesei CAZy transcripts showed reduced abundance in mixed cultures. The highly induced genes in mixed cultures indicated that fungal antagonism was a major part of the mixed cultures. In line with this, secondary metabolite producing gene clusters showed increased transcript abundance in mixed cultures and also mixed cultures with T. reesei led to a decrease in the mycelial biomass of A. niger. Significantly higher monomeric sugar release from straw was only measured using a minority of the mixed culture filtrates and there was no overall improvement. This study demonstrates fungal interaction with changes in transcripts, enzyme activities and biomass in the mixed cultures and whilst there were minor beneficial effects for CAZy transcripts and activities, the competitive interaction between T. reesei and the other fungi was the most prominent feature of this study.

  11. Two new ascomycetous anamorphic yeast species related to Candida friedrichii--Candida jaroonii sp. nov., and Candida songkhlaensis sp. nov.--isolated in Thailand.

    PubMed

    Imanishi, Yumi; Jindamorakot, Sasitorn; Mikata, Kozaburo; Nakagiri, Akira; Limtong, Savitree; Potacharoen, Wanchern; Tanticharoen, Morakot; Nakase, Takashi

    2008-08-01

    In a study of yeast diversity in Thailand, eight strains of hitherto undescribed anamorphic yeasts were isolated: four from insect frass, two from Marasmius sp. fruiting bodies, one from a flower, and one from jackfruit exudates. Phylogenetic analysis of the D1/D2 domain of 26S ribosomal DNA nucleotide sequences indicated that the eight strains represented two new species related to Candida friedrichii. Genetic separation of the two new species was further supported by DNA-DNA hybridization analysis, which resulted in between-species similarity values of less than 48%, and by electrophoretic karyotyping. The two new species are C. jaroonii sp. nov. (type strain, ST-300(T) = NBRC 103209(T) = BCC 11783(T) = CBS 10790(T)) and C. songkhlaensis sp. nov. (type strain, ST-328(T) = NBRC 103214(T) = BCC 11804(T) = CBS 10791(T)).

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

    PubMed

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

    2009-12-01

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

  13. Molecular data indicate that Rhytidhysteron rufulum (ascomycetes, Patellariales) in Costa Rica consists of four distinct lineages corroborated by morphological and chemical characters.

    PubMed

    Murillo, Catalina; Albertazzi, Federico J; Carranza, Julieta; Lumbsch, H Thorsten; Tamayo, Giselle

    2009-04-01

    Rhytidhysteron rufulum is a poorly known, common, pantropical species, capable of utilizing different substrata and occupying diverse habitats, and is the only species of its genus in Costa Rica. We have employed molecular, morphological, and chemical data to assess the variability and differentiation of R. rufulum in Costa Rica, including sites from the Pacific and Atlantic coast. Phylogenetic analyses of nuclear ITS rDNA sequences revealed the presence of four distinct lineages in the R. rufulum complex. Re-examination of the morphology and anatomy showed differences between these lineages in ascomatal, ascal, and ascospore size that have previously been regarded as intraspecific variations. In addition, there was a correlation between molecular phylogenies and chemical components as determined by hplc and nuclear magnetic resonance (NMR). Two lineages (clades I and II) produced the palmarumycins MK-3018, CJ-12372, and CR(1), whereas clade III produced dehydrocurvularin, and clade IV unidentified compounds. Our results based on a polyphasic approach contradict previous taxonomic interpretations of one morphologically variable species.

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

    PubMed Central

    Kurtzman, C P; Robnett, C J

    1997-01-01

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

  15. Long-term preservation, regeneration, and cultivation of Paecilomyces tenuipes (Peck) Samson (Ascomycetes), an entomopathogenic fungus inoculated into the silkworm larva of Bombyx mori.

    PubMed

    Nam, Sung Hee; Li, Chun Ru; Li, Zeng-Zhi; Fan, Mei-Zhen; Kang, Seok Woo; Lee, Kwang Gill; Yeo, Joo Hong; Hwang, Jae Sam; Choi, Ji Young; Han, Sang Mi; Lee, Ki Man

    2011-01-01

    Paecilomyces tenuipes reportedly have anticancer and immune activities, along with various other medicinal uses. Cultured products with P. tenuipes are certified for use in food in South Korea, and processed goods containing this fungus have been developed in many countries, particularly South Korea, Japan, and China. Research on mass production technology-procured raw materials for the manufacture of P. tenuipes is very important; however, cultures of the fungus have been unstable. This study identified stable cultivation conditions, focusing on growth inhibition and revitalization. Moisture regulation and preservation of pupae inoculated with P. tenuipes were used to control growth inhibition and revitalization. When inoculated silkworm pupae were dehydrated to 4% moisture and preserved freeze-dried or at -70 degrees C, -20 degrees C, or 4 degrees C, the mycelia in their bodies were able to survive for 14 d. Inoculated silkworm pupae were rehydrated for 3 h and the mycelia within their bodies were recovered at 94.3-96.3%. Silkworm pupae at 4% moisture were able to survive for 135 d at temperatures < 4 degrees C and for 1 y after freeze-drying. Optimal conditions for synnemata induction were 25 degrees C and 100-300 1x.

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

    PubMed

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

    2014-01-01

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

  17. 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...

  18. Draft Genome Sequencing of Ascomycetes Yeast Pichia membranifaciens KS47-1, Which Shows High Acetate Resistance in Lignocellulosic Feedstock Hydrolysate

    PubMed Central

    Arakawa, Tomoko; Kato, Yuta; Ishida, Masashi; Horiuchi, Jun-ichi

    2017-01-01

    ABSTRACT Pichia membranifaciens KS47-1 is capable of growing on hydrolysate containing high concentrations of acetate and other growth inhibitors. To reveal the acetate-resistant associate genes of strain KS47-1, we present the 11.4-Mb draft genome sequence. PMID:28232447

  19. Both open reading frames of the linear plasmid pMC3-2 from the ascomycete Morchella conica are transcribed in vivo.

    PubMed

    Rohe, M; Meinhardt, F

    1992-12-01

    Mitochondrial RNA was isolated from the morel strain Morchella conica 3 harbouring the linear plasmid pMC3-2 and subjected to gel electrophoresis followed by a Northern analysis using cloned fragments of the plasmid pMC3-2 as probes. Hybridization was obtained only with central parts of pMC3-2 and specific bands of mtRNA. The hybridization bands (2.8 kb and 1.0 kb) correspond in size to the length of the two ORFs of pMC3-2 which were deduced from nucleotide-sequence data. Thus, both ORFs, one encoding a DNA polymerase and the other a yet unknown protein, are transcribed in the mitochondria of the plasmid-bearing Morchella conica strain.

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

    PubMed

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

    2016-01-01

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

  1. Draft Genome Sequence of the Ascomycete Phaeoacremonium aleophilum Strain UCR-PA7, a Causal Agent of the Esca Disease Complex in Grapevines

    PubMed Central

    Blanco-Ulate, Barbara; Rolshausen, Philippe

    2013-01-01

    Grapevine infections by Phaeoacremonium aleophilum in association with other pathogenic fungi cause complex and economically important vascular diseases. Here we present the first draft of the P. aleophilum genome sequence, which comprises 624 scaffolds with a total length of 47.5 Mb (L50, 45; N50, 336 kb) and 8,926 predicted protein-coding genes. PMID:23814032

  2. Structural and functional characterization of the GalNAc/Gal-specific lectin from the phytopathogenic ascomycete Sclerotinia sclerotiorum (Lib.) de Bary.

    PubMed

    Candy, Laure; Van Damme, Els J M; Peumans, Willy J; Menu-Bouaouiche, Laurence; Erard, Monique; Rougé, Pierre

    2003-08-22

    The lectin found in mycelium and sclerotes of the phytopathogenic fungus Sclerotinia sclerotiorum is a homodimer consisting of two identical non-covalently bound subunits of 16,000 Da. CD spectra analysis revealed that the S. sclerotiorum agglutinin (SSA) contains predominantly beta-sheet structures. SSA exhibits specificity towards GalNAc whereby the hydroxyls at positions 4 and 6 of the pyranose ring play a key role in the interaction with simple sugars. The carbohydrate-binding site of SSA can also accommodate disaccharides. The N-terminal sequence of SSA shares no significant similarity with any other protein except a lectin from the Sclerotiniaceae species Ciborinia camelliae. A comparison of SSA and the lectins from C. camelliae and some previously characterized lectins indicates that the Sclerotiniaceae lectins form a homogeneous family of fungal lectins. This newly identified lectin family, which is structurally unrelated to any other family of fungal lectins, is most probably confined to the Ascomycota.

  3. Using human sera to identify a 52-kDa exoantigen of Penicillium chrysogenum and implications of polyphasic taxonomy of anamorphic ascomycetes in the study of antigenic proteins.

    PubMed

    Wilson, Aaron M; Luo, Wen; Miller, J David

    2009-11-01

    We are interested in isolating and identifying antigenic fungal proteins from species that grow on damp building materials. The indoor clade of Penicillium chrysogenum, the so-called Fleming clade, is the most common species of Penicillium on moldy building materials. We have identified a 52-kDa marker protein for the indoor clade of P. chrysogenum not present in a taxonomically diverse selection of fungi. It is found in high concentrations in protein extracted from the fungus grown on paper-faced gypsum wallboard. During this process, we illuminated the variability in response to patient sera and of strains of the fungus collected over a wide geographic area. From a collection of sera from all over the USA, 25 of the 48 patients reacted to the 52-kDa protein from this prescreened collection of sera. Most strain/antibody combinations had proportionate ELISA response associated with the presence of the target. However, approximately 25% of the strain/patient serum combinations included people who responded to many common allergens from the Penicillia. All the P. chrysogenum strains tested produced the target protein. However, there was considerable variability in patient IgG response to 32-, 30-, and 18-kDa antigens and in their production by the various clade 4 strains. The target protein was not found in spores or culture extracts of a wide selection of relevant fungi. It appears that the previous studies have been conducted on strains of the fungus from the three clades not those associated with the built environment.

  4. Effects of medium components and culture conditions on mycelial biomass and the production of bioactive ingredients in submerged culture of Xylaria nigripes (Ascomycetes), a Chinese medicinal fungus.

    PubMed

    Chen, Jian-Zhi; Lo, Hui-Chen; Lin, Fang-Yi; Chang, Shih-Liang; Hsieh, Changwei; Liang, Zeng-Chin; Ho, Wai-Jane; Hsu, Tai-Hao

    2014-01-01

    The optimal culture conditions were investigated to maximize the production of mycelial biomass and bioactive ingredients in submerged cultivation of Xylaria nigripes, a Chinese medicinal fungus. The one-factor-at-a-time method was used to explore the effects of medium components, including carbon, nitrogen, mineral sources, and initial pH of the medium and environmental factors, such as culture temperature and rotation speed, on mycelial growth and production of bioactive ingredients. The results indicated that the optimal culture temperature and rotation speed were 25°C and 100 rpm in a medium with 20 g fructose, 6 g yeast extract, and 2 g magnesiun sulfate heptahydrate as carbon, nitrogen, and mineral sources, respectively, in 1 L distilled water with an initial medium pH of 5.5. With optimal medium components and conditions of cultivation, the maximal production of mycelial biomass was 6.64 ± 0.88 g/L, with maximal production of bioactive ingredients such as extracellular polysaccharides (2.36 ± 0.18 mg/mL), intracellular polysaccharides (2.38 ± 0.07 mg/g), adenosine (43.27 ± 2.37 mg/g), total polyphenols (36.57 ± 1.36 mg/g), and triterpenoids (31.29 ± 1.17 mg/g) in a shake flask culture. These results suggest that different bioactive ingredients including intracellular polysaccharides, adenosine, total polyphenols and triterpenoids in mycelia and extracellular polysaccharides in broth can be obtained from one simple medium for submerged cultivation of X. nigripes.

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

    PubMed

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

    2014-01-01

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

  6. An attempt to prevent senescence: a mitochondrial approach.

    PubMed

    Skulachev, Vladimir P; Anisimov, Vladimir N; Antonenko, Yuri N; Bakeeva, Lora E; Chernyak, Boris V; Erichev, Valery P; Filenko, Oleg F; Kalinina, Natalya I; Kapelko, Valery I; Kolosova, Natalya G; Kopnin, Boris P; Korshunova, Galina A; Lichinitser, Mikhail R; Obukhova, Lidia A; Pasyukova, Elena G; Pisarenko, Oleg I; Roginsky, Vitaly A; Ruuge, Enno K; Senin, Ivan I; Severina, Inna I; Skulachev, Maxim V; Spivak, Irina M; Tashlitsky, Vadim N; Tkachuk, Vsevolod A; Vyssokikh, Mikhail Yu; Yaguzhinsky, Lev S; Zorov, Dmitry B

    2009-05-01

    Antioxidants specifically addressed to mitochondria have been studied to determine if they can decelerate senescence of organisms. For this purpose, a project has been established with participation of several research groups from Russia and some other countries. This paper summarizes the first results of the project. A new type of compounds (SkQs) comprising plastoquinone (an antioxidant moiety), a penetrating cation, and a decane or pentane linker has been synthesized. Using planar bilayer phospholipid membrane (BLM), we selected SkQ derivatives with the highest permeability, namely plastoquinonyl-decyl-triphenylphosphonium (SkQ1), plastoquinonyl-decyl-rhodamine 19 (SkQR1), and methylplastoquinonyldecyltriphenylphosphonium (SkQ3). Anti- and prooxidant properties of these substances and also of ubiquinonyl-decyl-triphenylphosphonium (MitoQ) were tested in aqueous solution, detergent micelles, liposomes, BLM, isolated mitochondria, and cell cultures. In mitochondria, micromolar cationic quinone derivatives were found to be prooxidants, but at lower (sub-micromolar) concentrations they displayed antioxidant activity that decreases in the series SkQ1=SkQR1>SkQ3>MitoQ. SkQ1 was reduced by mitochondrial respiratory chain, i.e. it is a rechargeable antioxidant. Nanomolar SkQ1 specifically prevented oxidation of mitochondrial cardiolipin. In cell cultures, SkQR1, a fluorescent SkQ derivative, stained only one type of organelles, namely mitochondria. Extremely low concentrations of SkQ1 or SkQR1 arrested H(2)O(2)-induced apoptosis in human fibroblasts and HeLa cells. Higher concentrations of SkQ are required to block necrosis initiated by reactive oxygen species (ROS). In the fungus Podospora anserina, the crustacean Ceriodaphnia affinis, Drosophila, and mice, SkQ1 prolonged lifespan, being especially effective at early and middle stages of aging. In mammals, the effect of SkQs on aging was accompanied by inhibition of development of such age-related diseases and traits

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

    NASA Astrophysics Data System (ADS)

    Skulachev, Vladimir P.

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

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

    PubMed Central

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

    2012-01-01

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

  9. Ribosomal DNA sequence divergence and group I introns within the Leucostoma species L. cinctum, L. persoonii, and L. parapersoonii sp. nov., ascomycetes that cause Cytospora canker of fruit trees.

    PubMed

    Adams, Gerard C; Surve-Iyer, Rupa S; Iezzoni, Amy F

    2002-01-01

    Leucostoma species that are the causal agents of Cytospora canker of stone and pome fruit trees were studied in detail. DNA sequence of the internal transcribed spacer regions and the 5.8S of the nuclear ribosomal DNA operon (ITS rDNA) supplied sufficient characters to assess the phylogenetic relationships among species of Leucostoma, Valsa, Valsella, and related anamorphs in Cytospora. Parsimony analysis of the aligned sequence divided Cytospora isolates from fruit trees into clades that generally agreed with the morphological species concepts, and with some of the phenetic groupings (PG 1-6) identified previously by isozyme analysis and cultural characteristics. Phylogenetic analysis inferred that isolates of L. persoonii formed two well-resolved clades distinct from isolates of L. cinctum. Phylogenetic analysis of the ITS rDNA, isozyme analysis, and cultural characteristics supported the inference that L. persoonii groups PG 2 and PG 3 were populations of a new species apparently more genetically different from L. persoonii PG 1 than from isolates representative of L. massariana, L. niveum, L. translucens, and Valsella melastoma. The new species, L. parapersoonii, was described. A diverse collection of isolates of L. cinctum, L. persoonii, and L. parapersoonii were examined for genetic variation using restriction fragment length polymorphism (RFLP) analysis of the ITS rDNA and the five prime end of the large subunit of the rDNA (LSU rDNA). HinfI and HpaII endonucleases were each useful in dividing the Leucostoma isolates into RFLP profiles corresponding to the isozyme phenetic groups, PG 1-6. RFLP analysis was more effective than isozyme analysis in uncovering variation among isolates of L. persoonii PG 1, but less effective within L. cinctum populations. Isolates representative of seven of the L. persoonii formae speciales proposed by G. Défago in 1935 were found to be genetically diverse isolates of PG 1. Two large insertions, 415 and 309 nucleotides long, in the small subunit (SSU) of the nuclear rDNA of L. cinctum were identified as Group 1 introns; intron 1 at position 943 and intron 2 at position 1199. The two introns were found to be consistently present in isolates of L. cinctum PG 4 and PG 5 and absent from L. cinctum PG 6 isolates, despite the similarity of the ITS sequence and teleomorph morphology. Intron 1 was of subgroup 1C1 whereas intron 2 was of an unknown subgroup. RFLP patterns and presence/absence of introns were useful characters for expediting the identification of cultures of Leucostoma isolated from stone and pome fruit cankers. RFLP patterns from 13 endonucleases provided an effective method for selecting an array of diverse PG 1 isolates useful in screening plant germplasm for disease-resistance.

  10. Ogataea neopini sp. nov. and O. corticis sp. nov., with the emendation of the ascomycete yeast genus Ogataea, and transfer of Pichia zsoltii, P. dorogensis, and P. trehaloabstinens to it.

    PubMed

    Nagatsuka, Yuka; Saito, Satoshi; Sugiyama, Junta

    2008-12-01

    During a survey of yeast strains having high conversion efficiency to ethanol from cellobiose, 'Ogataea pini' ATCC 28781 and 'Pichia pini' NBRC 1794 were found to be distinct from any known species and from each other by a BLAST homology search using the D1/D2 LSU rRNA gene sequences. The D1/D2 phylogeny showed that 'O. pini' ATCC 28781 and 'P. pini' NBRC 1794 belonged to the Ogataea cluster, whereas a comparison of the ITS 1 and 2 regions sequences showed that the ATCC and NBRC strains each formed a species distinct from O. ganodermae, O. pini, O. henricii, and P. zsoltii, based on the D1/D2 sequence divergence. The ATCC and NBRC strains formed two to four hat-shaped ascospores and two to four, or more ones per deliquescent ascus, respectively, were negative for DBB and urease reactions, assimilated methanol slowly and nitrate not at all, and had the major ubiquinone system Q-7. These characteristics coincided basically with the definition of Ogataea proposed by Yamada et al. in 1994, excluding the number of ascospores. On the other hand, the ATCC and NBRC strains differed not only from each other but from relatives in various phenotypic characteristics. These differences suggest that two new yeasts of Ogataea be described as novel. The new species and their type strains are as follows: O. neopini ATCC 28781(T); and O. corticis NBRC 1794(T). In addition, the emendation of the genus Ogataea is made; besides, we propose the transfer of P. zsoltii, P. dorogensis, and P. trehaloabstinens, which were placed in the Ogataea cluster based on the D1/D2 sequence analysis, to the genus Ogataea as O. zsoltii comb. nov., O. dorogensis comb. nov., and O. trehaloabstinens comb. nov.

  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. Three novel ascomycetous yeast species of the Kazachstania clade, Kazachstania saulgeensis sp. nov., Kazachstaniaserrabonitensis sp. nov. and Kazachstania australis sp. nov. Reassignment of Candida humilis to Kazachstania humilis f.a. comb. nov. and Candida pseudohumilis to Kazachstania pseudohumilis f.a. comb. nov.

    PubMed

    Jacques, Noémie; Sarilar, Véronique; Urien, Charlotte; Lopes, Mariana R; Morais, Camila G; Uetanabaro, Ana Paula T; Tinsley, Colin R; Rosa, Carlos A; Sicard, Delphine; Casaregola, Serge

    2016-12-01

    Five ascosporogenous yeast strains related to the genus Kazachstania were isolated. Two strains (CLIB 1764T and CLIB 1780) were isolated from French sourdoughs; three others (UFMG-CM-Y273T, UFMG-CM-Y451 and UFMG-CM-Y452) were from rotting wood in Brazil. The sequences of the French and Brazilian strains differed by one and three substitutions, respectively, in the D1/D2 large subunit (LSU) rRNA gene and the internal transcribed spacer (ITS). The D1/D2 LSU rRNA sequence of these strains differed by 0.5 and 0.7 % from Kazachstania exigua, but their ITS sequences diverged by 8.1 and 8.3 %, respectively, from that of the closest described species Kazachstania barnettii. Analysis of protein coding sequences of RPB1, RPB2 and EF-1α distinguished the French from the Brazilian strains, with respectively 3.3, 6 and 11.7 % substitutions. Two novel species are described to accommodate these newly isolated strains: Kazachstania saulgeensis sp. nov. (type strain CLIB 1764T=CBS 14374T) and Kazachstania serrabonitensis sp. nov. (type strain UFMG-CM-Y273T=CLIB 1783T=CBS 14236T). Further analysis of culture collections revealed a strain previously assigned to the K. exigua species, but having 3.8 % difference (22 substitutions and 2 indels) in its ITS with respect to K. exigua. Hence, we describe a new taxon, Kazachstania australis sp. nov. (type strain CLIB 162T=CBS 2141T), to accommodate this strain. Finally, Candida humilis and Candida pseudohumilis are reassigned to the genus Kazachstania as new combinations. On the basis of sequence analysis, we also propose that Candida milleri and Kazachstania humilis comb. nov. are conspecific.

  13. 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...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  15. 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...

  16. 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 ...

  17. Rearrangements of the transcriptional regulatory networks of metabolic pathways in fungi.

    PubMed

    Lavoie, Hugo; Hogues, Hervé; Whiteway, Malcolm

    2009-12-01

    Growing evidence suggests that transcriptional regulatory networks in many organisms are highly flexible. Here, we discuss the evolution of transcriptional regulatory networks governing the metabolic machinery of sequenced ascomycetes. In particular, recent work has shown that transcriptional rewiring is common in regulons controlling processes such as production of ribosome components and metabolism of carbohydrates and lipids. We note that dramatic rearrangements of the transcriptional regulatory components of metabolic functions have occurred among ascomycetes species.

  18. Ultrastructure and cytochemical localization of laccase in two strains of Leptosphaerulina briosiana (Pollaci) Graham and Luttrell.

    PubMed Central

    Simon, L T; Bishop, D S; Hooper, G R

    1979-01-01

    Substrate specificity tests were used to identify the presence of laccase in two strains of Leptosphaerulina briosiana (Poll.) Graham and Luttrell, an ascomycete which causes leaf spot in alfalfa. Cytochemical localization of monophenol monooxygenase (laccase) as well as the ultrastructures of the two strains were investigated. Laccase was observed in the outer layers of the cell walls of both strains. The ultrastructures of vegetative hyphae of both strains were typical of those found in most ascomycetes. Images PMID:104971

  19. Cytochrome P450 monooxygenase CYP53 family in fungi: comparative structural and evolutionary analysis and its role as a common alternative anti-fungal drug target.

    PubMed

    Jawallapersand, Poojah; Mashele, Samson Sitheni; Kovačič, 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

  20. 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; Kovačič, 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

  1. Assemblage and diversity of fungi on wood and seaweed litter of seven northwest portuguese beaches.

    PubMed

    Sridhar, K R; Karamchand, K S; Pascoal, C; Cássio, F

    2012-01-01

    Three hundred and fifty woody litter and one hundred and forty seaweed litter sampled from seven beaches of Northwest Portugal were assessed for the filamentous fungal assemblage and diversity. The woody litter was screened for fungi up to 42 months using damp chamber incubation. They consisted of 36 taxa (ascomycetes, 21; basidiomycetes, 3; anamorphic taxa, 12) comprising 10 core group taxa (≥10%) (ascomycetes, 8; basidiomycete, 1; anamorphic taxa, 1). The total fungal isolates ranged between 150 and 243, while the number of fungal taxa per wood ranged between 3 and 4.9. The seaweed litter was screened up to four months in damp chamber incubation. They encompassed 29 taxa (ascomycetes, 16; basidiomycetes, 2; anamorphic taxa, 11) comprising 15 core group taxa (ascomycetes, 9; basidiomycete, 1; anamorphic taxa, 5). Total fungal isolates ranged between 56 and 120, while the number of fungal taxa per seaweed segment ranged between 4.8 and 6.3. Fifteen taxa of ascomycetes, two of basidiomycetes, and four anamorphic taxa were common to wood and seaweed litter. On both the substrates, two arenicolous fungi Arenariomyces trifurcates and Corollospora maritima were the predominant fungi (72.6-85.9%). The species abundance curves showed higher frequency of occurrence of fungal taxa in seaweed than woody litter. Our study revealed rich assemblage and diversity of marine fungi on wood and seaweed litter of Northwest Portugal beaches. The fungal composition and diversity of this survey have been compared with earlier investigations on marine fungi of Portugal coast.

  2. The Complete Mitochondrial Genome of Aix galericulata and Tadorna ferruginea: Bearings on Their Phylogenetic Position in the Anseriformes

    PubMed Central

    Liu, Gang; Zhou, Lizhi; Li, Bo; Zhang, Lili

    2014-01-01

    Aix galericulata and Tadorna ferruginea are two Anatidae species representing different taxonomic groups of Anseriformes. We used a PCR-based method to determine the complete mtDNAs of both species, and estimated phylogenetic trees based on the complete mtDNA alignment of these and 14 other Anseriforme species, to clarify Anseriform phylogenetics. Phylogenetic trees were also estimated using a multiple sequence alignment of three mitochondrial genes (Cyt b, ND2, and COI) from 68 typical species in GenBank, to further clarify the phylogenetic relationships of several groups among the Anseriformes. The new mtDNAs are circular molecules, 16,651 bp (Aix galericulata) and 16,639 bp (Tadorna ferruginea) in length, containing the 37 typical genes, with an identical gene order and arrangement as those of other Anseriformes. Comparing the protein-coding genes among the mtDNAs of 16 Anseriforme species, ATG is generally the start codon, TAA is the most frequent stop codon, one of three, TAA, TAG, and T-, commonly observed. All tRNAs could be folded into canonical cloverleaf secondary structures except for tRNASer (AGY) and tRNALeu (CUN), which are missing the "DHU" arm.Phylogenetic relationships demonstrate that Aix galericula and Tadorna ferruginea are in the same group, the Tadorninae lineage, based on our analyses of complete mtDNAs and combined gene data. Molecular phylogenetic analysis suggests the 68 species of Anseriform birds be divided into three families: Anhimidae, Anatidae, and Anseranatidae. The results suggest Anatidae birds be divided into five subfamilies: Anatinae, Tadorninae, Anserinae, Oxyurinae, and Dendrocygninae. Oxyurinae and Dendrocygninae should not belong to Anserinae, but rather represent independent subfamilies. The Anatinae includes species from the tribes Mergini, Somaterini, Anatini, and Aythyini. The Anserinae includes species from the tribes Anserini and Cygnini. PMID:25375111

  3. Ectomycorrhizal fungal communities of oak savanna are distinct from forest communities.

    PubMed

    Dickie, I A; Dentinger, B T M; Avis, P G; McLaughlin, D J; Reich, P B

    2009-01-01

    Oak savanna is one of the most endangered ecosystems of North America, with less than 0.02% of its original area remaining. Here we test whether oak savanna supports a unique community of ectomycorrhizal fungi, a higher diversity of ectomycorrhizal fungi or a greater proportional abundance of ascomycete fungi compared with adjacent areas where the absence of fire has resulted in oak savanna conversion to oak forest. The overall fungal community was highly diverse and dominated by Cenococcum geophilum and other ascomycetes, Cortinarius, Russula, Lactarius and Thelephoraceae. Oak savanna mycorrhizal communities were distinct from oak forest communities both aboveground (sporocarp surveys) and belowground (RFLP identification of ectomycorrhizal root tips); however total diversity was not higher in oak savanna than oak forests and there was no evidence of a greater abundance of ascomycetes. Despite not having a higher local diversity than oak forests, the presence of a unique fungal community indicates that oak savanna plays an important role in maintaining regional ectomycorrhizal diversity.

  4. Phi Class of Glutathione S-transferase Gene Superfamily Widely Exists in Nonplant Taxonomic Groups

    PubMed Central

    Munyampundu, Jean-Pierre; Xu, You-Ping; Cai, Xin-Zhong

    2016-01-01

    Glutathione S-transferases (GSTs) constitute a superfamily of enzymes involved in detoxification of noxious compounds and protection against oxidative damage. GST class Phi (GSTF), one of the important classes of plant GSTs, has long been considered as plant specific but was recently found in basidiomycete fungi. However, the range of nonplant taxonomic groups containing GSTFs remains unknown. In this study, the distribution and phylogenetic relationships of nonplant GSTFs were investigated. We identified GSTFs in ascomycete fungi, myxobacteria, and protists Naegleria gruberi and Aureococcus anophagefferens. GSTF occurrence in these bacteria and protists correlated with their genome sizes and habitats. While this link was missing across ascomycetes, the distribution and abundance of GSTFs among ascomycete genomes could be associated with their lifestyles to some extent. Sequence comparison, gene structure, and phylogenetic analyses indicated divergence among nonplant GSTFs, suggesting polyphyletic origins during evolution. Furthermore, in silico prediction of functional partners suggested functional diversification among nonplant GSTFs. PMID:26884677

  5. 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

  6. In vitro decomposition of Sphagnum by some microfungi resembles white rot of wood.

    PubMed

    Rice, Adrianne V; Tsuneda, Akihiko; Currah, Randolph S

    2006-06-01

    The abilities of some ascomycetes (Myxotrichaceae) from a Sphagnum bog in Alberta to degrade cellulose, phenolics, and Sphagnum tissue were compared with those of two basidiomycetes. Most Myxotrichaceae degraded cellulose and tannic acid, and removed cell-wall components simultaneously from Sphagnum tissues, whereas the basidiomycetes degraded cellulose and insoluble phenolics, and preferentially removed the polyphenolic matrix from Sphagnum cell walls. Mass losses from Sphagnum varied from up to 50% for some ascomycetes to a maximum of 35% for the basidiomycetes. The decomposition of Sphagnum by the Myxotrichaceae was analogous to the white rot of wood and indicates that these fungi have the potential to cause significant mineralization of carbon in bogs.

  7. 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.

  8. Plant Clonal Integration Mediates the Horizontal Redistribution of Soil Resources, Benefiting Neighboring Plants

    PubMed Central

    Ye, Xue-Hua; Zhang, Ya-Lin; Liu, Zhi-Lan; Gao, Shu-Qin; Song, Yao-Bin; Liu, Feng-Hong; Dong, Ming

    2016-01-01

    Resources such as water taken up by plants can be released into soils through hydraulic redistribution and can also be translocated by clonal integration within a plant clonal network. We hypothesized that the resources from one (donor) microsite could be translocated within a clonal network, released into different (recipient) microsites and subsequently used by neighbor plants in the recipient microsite. To test these hypotheses, we conducted two experiments in which connected and disconnected ramet pairs of Potentilla anserina were grown under both homogeneous and heterogeneous water regimes, with seedlings of Artemisia ordosica as neighbors. The isotopes [15N] and deuterium were used to trace the translocation of nitrogen and water, respectively, within the clonal network. The water and nitrogen taken up by P. anserina ramets in the donor microsite were translocated into the connected ramets in the recipient microsites. Most notably, portions of the translocated water and nitrogen were released into the recipient microsite and were used by the neighboring A. ordosica, which increased growth of the neighboring A. ordosica significantly. Therefore, our hypotheses were supported, and plant clonal integration mediated the horizontal hydraulic redistribution of resources, thus benefiting neighboring plants. Such a plant clonal integration-mediated resource redistribution in horizontal space may have substantial effects on the interspecific relations and composition of the community and consequently on ecosystem processes. PMID:26904051

  9. Registration of 42 blast resistant medium grain rice genetic stocks with suitable agronomic, yield, milling yield, and grain characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice blast disease caused by the filamentous ascomycete fungus Magnaporthe oryzae Cav. [Magnaporthe grisea (Herbert) Barr.] is one of the most threatening rice diseases in the southern United States. In the present study, 42 rice (Oryza sativa L.) blast resistant genetic stocks (GSOR102501 to 201542...

  10. Genome sequences of three phytopathogenic species of the Magnaporthaceae family of fungi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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), ...

  11. Development of molecular markers for breeding for disease resistant crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rice blast disease caused by the filamentous ascomycetes fungus Magnaporthe oryzae and sheath blight disease caused by the soil borne fungus Rhizocotonia solani are the two major rice diseases that threaten stable rice production in the USA and worldwide. These two diseases have been managed with a ...

  12. Altering sexual reproductive mode by interspecific exchange of MAT loci

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sexual fungi can be self-sterile (heterothallic, requiring genetically distinct partners) or selffertile (homothallic, no partner required). In most ascomycetes, a single mating type locus (MAT) controls the ability to reproduce sexually. In the genus Cochliobolus, all heterothallic species have eit...

  13. First report of wheat blast caused by magnaporthe oryzae pathotype triticum in Bangladesh

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat blast or ‘brusone’, caused by the ascomycetous fungus Magnaporthe oryzae B.C. Couch (synonym Pyricularia oryzae Cavara), was first identified in 1985 in Brazil. M. oryzae is composed of a range of morphologically identical but genetically different host-specific pathotypes that are specialized...

  14. Early detection of airborne inoculum of Magnaporthe oryzae in turfgrass fields using a quantitative LAMP assay

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gray leaf spot (GLS) is a destructive disease of perennial ryegrass caused by a host specific pathotype of the ascomycete Magnaporthe oryzae. Early diagnosis is crucial for effective disease management and the implementation of Integrated Pest Management practices. However, a rapid diagnostic protoc...

  15. 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...

  16. 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...

  17. Genetic relationships of boxwood (Buxus L.) accessions based on genic simple sequence repeat markers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Boxwood (Buxus L. spp., Buxaceae) are popular woody landscape shrubs grown for their diverse forms and broad-leaved evergreen foliage. Boxwood plants grown in temperate zones are now threatened by a destructive new blight disease caused by the ascomycete fungus Calonectria pseudonaviculata Henricot ...

  18. Comparative genomics of biotechnologically important yeasts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ascomycete yeasts are metabolically diverse, with great potential for biotechnology. Here, we report the comparative genome analysis of 29 taxonomically and biotechnologically important yeasts, including 16 newly sequenced. We identify a genetic code change, CUG-Ala, in Pachysolen tannophilus in the...

  19. Draft Genome Sequence of Diplodia seriata F98.1, a Fungal Species Involved in Grapevine Trunk Diseases.

    PubMed

    Robert-Siegwald, Guillaume; Vallet, Julie; Abou-Mansour, Eliane; Xu, Jiabao; Rey, Patrice; Bertsch, Christophe; Rego, Cecilia; Larignon, Philippe; Fontaine, Florence; Lebrun, Marc-Henri

    2017-04-06

    The ascomycete Diplodia seriata is a causal agent of grapevine trunk diseases. Here, we present the draft genome sequence of D. seriata isolate F98.1 (37.27 Mb, 512 contigs, 112 scaffolds, and 8,087 predicted protein-coding genes).

  20. Complete Mitochondrial Genome Sequence of the Pezizomycete Pyronema confluens

    PubMed Central

    2016-01-01

    The complete mitochondrial genome of the ascomycete Pyronema confluens has been sequenced. The circular genome has a size of 191 kb and contains 48 protein-coding genes, 26 tRNA genes, and two rRNA genes. Of the protein-coding genes, 14 encode conserved mitochondrial proteins, and 31 encode predicted homing endonuclease genes. PMID:27174271

  1. NMR metabolomics analysis of the effect of elevated CO2 on wheat resistance to Fusarium head blight

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium head blight (FHB), primarily induced by the filamentous ascomycete Fusarium graminearum (Fg), is one of the most damaging diseases in wheat and other small grain cereals worldwide. Current methods for disease control include utilization of less susceptible cultivars and treatment with fungi...

  2. Draft Genome Sequence of Coniochaeta ligniaria NRRL 30616, a Lignocellulolytic Fungus for Bioabatement of Inhibitors in Plant Biomass Hydrolysates

    PubMed Central

    Jiménez, Diego Javier; Hector, Ronald E.; Riley, Robert; Lipzen, Anna; Kuo, Rita C.; Amirebrahimi, Mojgan; Barry, Kerrie W.; Grigoriev, Igor V.; van Elsas, Jan Dirk

    2017-01-01

    ABSTRACT Here, we report the first draft genome sequence (42.38 Mb containing 13,657 genes) of Coniochaeta ligniaria NRRL 30616, an ascomycete with biotechnological relevance in the bioenergy field given its high potential for bioabatement of toxic furanic compounds in plant biomass hydrolysates and its capacity to degrade lignocellulosic material. PMID:28126934

  3. 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...

  4. Lodderomyces van der Walt (1971)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes the ascomycete yeast genus Lodderomyces and is to be published in “The Yeasts, A Taxonomic Study, 5th edition.” The genus Lodderomyces has one species, L. elongisporus. The species has been isolated as a spoilage agent of fruit juices and concentrates, from soil and from hum...

  5. 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...

  6. 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...

  7. 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...

  8. 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...

  9. 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

  10. 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...

  11. Ogataea Y. Yamada, K. Maeda & Mikata (1994)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The chapter describes the ascomycete yeast genus Ogataea and is to be published in TheYeasts, A Taxonomic Study, 5th edition. The genus Ogataea includes 31 species, many described in the last few years as a result of the availability of species-specific gene sequence databases. All but one of the ...

  12. Surveys for Pathogens of Monoecious Hydrilla

    DTIC Science & Technology

    2014-01-01

    purpose of the study presented herein was to survey some known populations of monoecious hydrilla and isolate potential fungal pathogens. MATERIALS ...sporulating species herein noted as dematiaceous (dark mycelium ) or moniliaceous (hyaline mycelium ) Ascomycetes (Table 1). The majority of the species

  13. 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...

  14. Entomopathogenic fungi in cornfields and their potential to manage larval western corn rootworm Diabrotica virgifera virgifera

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Entomopathogenic Ascomycete fungi are ubiquitous in soil and on phylloplanes, and are important natural enemies of many arthropods, including larval western corn rootworm, Diabrotica virgifera virgifera, which is a major pest of corn. We measured the prevalence of Beauveria bassiana and Metarhizium...

  15. 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 ...

  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. 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...

  18. Draft Genome Sequence of Coniochaeta ligniaria NRRL 30616, a Lignocellulolytic Fungus for Bioabatement of Inhibitors in Plant Biomass Hydrolysates.

    PubMed

    Jiménez, Diego Javier; Hector, Ronald E; Riley, Robert; Lipzen, Anna; Kuo, Rita C; Amirebrahimi, Mojgan; Barry, Kerrie W; Grigoriev, Igor V; van Elsas, Jan Dirk; Nichols, Nancy N

    2017-01-26

    Here, we report the first draft genome sequence (42.38 Mb containing 13,657 genes) of Coniochaeta ligniaria NRRL 30616, an ascomycete with biotechnological relevance in the bioenergy field given its high potential for bioabatement of toxic furanic compounds in plant biomass hydrolysates and its capacity to degrade lignocellulosic material.

  19. 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...

  20. Trichomonascus H.S. Jackson emend. Kurtzman & Robnett (2007)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes the ascomycete yeast genus Trichomonascus and is to be published in "The Yeasts, A Taxonomic Study, 5th edition." The genus Trichomonascus has six known species, two of which have not been grown in laboratory culture. Multigene phylogenetic analysis places the genus near the...

  1. 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...

  2. 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...

  3. 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...

  4. A ToxA-like protein from Cochliobolus heterostrophus induces light-dependent leaf necrosis with host selectivity on maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ToxA, the first discovered fungal proteinaceous host-selective toxin (HST), was originally identified from Pyrenophora tritici-repentis (Ptr), and its homologues have not been identified from any other ascomycetes except Parastagonospora nodorum. Here we report the identification of a ToxA-like pro...

  5. Molecular cloning and characterization of a ToxA-like gene from the maize pathogen Cochliobolus heterostrophus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ToxA, the first discovered fungal proteinaceous host-selective toxin, was originally identified from the tan spot fungus Pyrenophora tritici-repentis (Ptr). Homologues of the PtrToxA gene have not been identified from any other ascomycetes except the leaf/glume blotch fungus Stagonospora nodorum, w...

  6. Description of Groenewaldozyma gen. nov. for placement of Candida auringiensis, Candida salmanticensis and Candida tartarivorans

    Technology Transfer Automated Retrieval System (TEKTRAN)

    DNA sequence analyses have demonstrated that species of the polyphyletic anamorphic ascomycete genus Candida may be members of described teleomorphic genera, members of the Candida tropicalis clade upon which the genus Candida is circumscribed, or members of isolated clades that represent undescribe...

  7. Genome Sequence and Annotation of Colletotrichum higginsianum, a Causal Agent of Crucifer Anthracnose Disease

    PubMed Central

    Zampounis, Antonios; Pigné, Sandrine; Dallery, Jean-Félix; Wittenberg, Alexander H. J.; Zhou, Shiguo; Schwartz, David C.

    2016-01-01

    Colletotrichum higginsianum is an ascomycete fungus causing anthracnose disease on numerous cultivated plants in the family Brassicaceae, as well as the model plant Arabidopsis thaliana. We report an assembly of the nuclear genome and gene annotation of this pathogen, which was obtained using a combination of PacBio long-read sequencing and optical mapping. PMID:27540062

  8. [Cordyceps sinensis, a fungi used in the Chinese traditional medicine].

    PubMed

    Illana Esteban, Carlos

    2007-12-31

    Cordyceps sinensis (Berk.) Sacc. is an ascomycete fungus known in China since antiquity, which is still being used today. A summary, showing relevant papers about this fungus, regarding habitat, history, marketing, consumption, nomenclature, pharmacological composition, culture and medical use, is presented.

  9. Generation of reactive oxygen species via NOXa is important for development and pathogenicity of mycosphaerella graminicola

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ascomycete fungus Mycosphaerella graminicola is an important pathogen of wheat causing economically significant losses. The primary nutritional mode of this fungus is thought to be hemibiotrophic. This pathogenic lifestyle is associated with an early biotrophic stage of nutrient uptake followed ...

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

    SciTech Connect

    Pomraning, Kyle R.; Baker, Scott E.

    2015-11-25

    Here, we present the draft genome sequence of the dimorphic ascomycete yeastYarrowia lipolyticastrain W29 (ATCC 20460).Y. lipolyticais a commonly employed model for the industrial production of lipases, small molecules, and more recently for its ability to accumulate lipids.

  11. Immune Response of Mormon Crickets that Survived Infection by Beauveria Bassiana

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Beauveria bassiana is an entomopathogenic Ascomycete fungus that serves as a biological control agent of Mormon crickets (Anabrus simplex Haldeman) and other grasshopper pests. To measure the dose dependent response of Mormon crickets to fungal attack, we applied B. bassiana strain GHA topically to...

  12. 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) ...

  13. NRPS4 is responsible for the biosynthesis of destruxins in Metarhizium robertsii ARSEF 2575

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Destruxins (DTXs) are a family of cyclic depsipeptides that include > 35 members produced by Ascomycetous fungi belonging to several different taxa. These metabolites display a plethora of biological activities including toxicity against insects, depolarization of Ca2+ gradient across the plasma mem...

  14. 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 ...

  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. 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...

  17. 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 ...

  18. Structural analysis of the inhibition of Pyrenophora teres by Laetisaria arvalis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The basidiomycete fungus, Laetisaria arvalis has been reported to have biological control activity over some plant pathogens [1]. This soil-inhabiting Basidiomycete strain was isolated in a Nebraska sugar beet field [3] . Net blotch, a foliar disease of barley, is caused by the ascomycete fungus Py...

  19. Draft Genome Sequence of Diplodia seriata F98.1, a Fungal Species Involved in Grapevine Trunk Diseases

    PubMed Central

    Robert-Siegwald, Guillaume; Vallet, Julie; Abou-Mansour, Eliane; Xu, Jiabao; Rey, Patrice; Bertsch, Christophe; Rego, Cecilia; Larignon, Philippe; Fontaine, Florence

    2017-01-01

    ABSTRACT The ascomycete Diplodia seriata is a causal agent of grapevine trunk diseases. Here, we present the draft genome sequence of D. seriata isolate F98.1 (37.27 Mb, 512 contigs, 112 scaffolds, and 8,087 predicted protein-coding genes). PMID:28385831

  20. Global analyses of Ceratocystis cacaofunesta mitochondria: from genome to proteome

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background The ascomycete fungus Ceratocystis cacaofunesta is the causal agent of wilt disease in cacao, which results in significant economic losses in the affected producing areas. Despite the economic importance of the Ceratocystis complex of species, no genomic data are available for any of its ...

  1. 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...

  2. Random T-DNA mutagenesis identifies a Cu-Zn-superoxide dismutase gene as a virulence factor of Sclerotinia sclerotiorum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Ascomycetous fungus Sclerotinia sclerotiorum is a devastating pathogen capable of infecting more than 400 plant species including many economically important crops. In order to gain a better mechanistic understanding of its non-specific host-pathogen interactions, random mutagenesis through Agro...

  3. High-Quality Draft Genome Sequence of Candida apicola NRRL Y-50540.

    PubMed

    Vega-Alvarado, Leticia; Gómez-Angulo, Jorge; Escalante-García, Zazil; Grande, Ricardo; Gschaedler-Mathis, Anne; Amaya-Delgado, Lorena; Sanchez-Flores, Alejandro; Arrizon, Javier

    2015-06-11

    Candida apicola, a highly osmotolerant ascomycetes yeast, produces sophorolipids (biosurfactants), membrane fatty acids, and enzymes of biotechnological interest. The genome obtained has a high-quality draft for this species and can be used as a reference to perform further analyses, such as differential gene expression in yeast from Candida genera.

  4. High-Quality Draft Genome Sequence of Candida apicola NRRL Y-50540

    PubMed Central

    Vega-Alvarado, Leticia; Gómez-Angulo, Jorge; Escalante-García, Zazil; Grande, Ricardo; Gschaedler-Mathis, Anne; Amaya-Delgado, Lorena

    2015-01-01

    Candida apicola, a highly osmotolerant ascomycetes yeast, produces sophorolipids (biosurfactants), membrane fatty acids, and enzymes of biotechnological interest. The genome obtained has a high-quality draft for this species and can be used as a reference to perform further analyses, such as differential gene expression in yeast from Candida genera. PMID:26067948

  5. SNP discovery and QTL mapping of Sclerotinia basal stalk rot resistance in sunflower using genotyping-by-sequencing (GBS)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Basal stalk rot (BSR) caused by the ascomycete fungus Sclerotinia sclerotiorum (Lib.) de Bary is a serious disease of sunflower (Helianthus annuus L.) in the cool and humid production areas of the world. Quantitative trait loci (QTL) for BSR resistance were identified in a sunflower recombinant inbr...

  6. 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...

  7. Condition-dependent co-regulation of genomic clusters of virulence factors in the grapevine trunk pathogen Neofusicoccum parvum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ascomycete Neofusicoccum parvum, one of the causal agents of Botryosphaeria dieback, is a destructive wood-infecting fungus and a serious threat to grape production worldwide. The capability of colonizing woody tissue combined with the secretion of phytotoxic compounds is thought to underlie its...

  8. 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...

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

    PubMed

    Johnson, Eric A

    2013-09-01

    Yeasts are the major producer of biotechnology products worldwide, exceeding production in capacity and economic revenues of other groups of industrial microorganisms. Yeasts have wide-ranging fundamental and industrial importance in scientific, food, medical, and agricultural disciplines (Fig. 1). Saccharomyces is the most important genus of yeast from fundamental and applied perspectives and has been expansively studied. Non-Saccharomyces yeasts (non-conventional yeasts) including members of the Ascomycetes and Basidiomycetes also have substantial current utility and potential applicability in biotechnology. In an earlier mini-review, "Biotechnology of non-Saccharomyces yeasts-the ascomycetes" (Johnson Appl Microb Biotechnol 97: 503-517, 2013), the extensive biotechnological utility and potential of ascomycetous yeasts are described. Ascomycetous yeasts are particularly important in food and ethanol formation, production of single-cell protein, feeds and fodder, heterologous production of proteins and enzymes, and as model and fundamental organisms for the delineation of genes and their function in mammalian and human metabolism and disease processes. In contrast, the roles of basidiomycetous yeasts in biotechnology have mainly been evaluated only in the past few decades and compared to the ascomycetous yeasts and currently have limited industrial utility. From a biotechnology perspective, the basidiomycetous yeasts are known mainly for the production of enzymes used in pharmaceutical and chemical synthesis, for production of certain classes of primary and secondary metabolites such as terpenoids and carotenoids, for aerobic catabolism of complex carbon sources, and for bioremediation of environmental pollutants and xenotoxicants. Notwithstanding, the basidiomycetous yeasts appear to have considerable potential in biotechnology owing to their catabolic utilities, formation of enzymes acting on recalcitrant substrates, and through the production of unique primary

  10. Phylogenetic studies of two Anas platyrhynchos (Anatini: Anatinae) in Hunan province of China based on complete mitochondrial DNA sequences.

    PubMed

    He, Xi; Lin, Qian; Cao, Rong; Yuan, Ya-Ting; Pan, Di-Zi; Yun, Long; Zhang, Shi-Rui; Hou, De-Xing

    2016-07-01

    In this study, we cloned and sequenced the complete mitochondrial DNAs of Chinese duck, Anas platyrhynchos, population from two different areas of Hunan province in China. The Anas platyrhynchos breed Linwu duck (LW) sample was taken from the Linwu county of Chenzhou city, and the Anas platyrhynchos breed Youxian duck (YX) sample was taken from the Youxian county of Zhuzhou city. The lengths of their complete mitochondrial genome were 16,604 bp (LW) and 16,606 bp (YX), respectively. The organization of the two Anas platyrhynchos breed mitochondrial genomes was similar to those reported from other duck mitochondrial genomes. Phylogenetic analyses using N-J computational algorithms showed that the analyzed species are divided into four major clades: Anatinae, Anserinae, Dendrocygninae and Anseranatidae. Also, the Linwu duck and Youxian duck have highly similar phylogenetic relationship.

  11. Aqueous Extracts of Selected Potentilla Species Modulate Biological Activity of Human Normal Colon Cells.

    PubMed

    Paduch, Roman; Wiater, Adrian; Locatelli, Marcello; Pleszczyńska, Malgorzata; Tomczyk, Michal

    2015-01-01

    Potentilla L. (Rosaceae) species have been used in traditional and in folk medicine for many years. This study characterized the activity of extracts from aerial parts of selected Potentilla species: P. argentea, P. anserina, P. grandiflora and P. erecta as well as one species of closely related to the genus Potentilla, Drymocallis rupestris (syn. P. rupestris). The biological activities were analyzed using MTT, NR and DPPH assays on CCD 841 CoTr and CCD-18Co cells. Moreover, cell morphology and cytoskeletal actin F-filaments organization and IL-6 and IL-10 levels by ELISA were analyzed after 24 h of incubation. Potentilla extracts at dose levels between 25 and 250 µg/mL were analyzed. For ELISA, 15 µg/mL and 30 μg/mL were chosen. When mitochondrial succinyl dehydrogenase activity was tested (MTT assay) only extract obtained from P. erecta at lower concentrations (up to 125 µg/mL) suppressed metabolism of myofibroblasts, while epithelial cells mitochondrial enzyme activity increased after incubation with all extracts. In Neutral Red (NR) method cellular membrane disturbance of both cell cultures was found after D. rupestris and P. grandiflora addition. Moreover, strong influence on epithelial cells was also found for P. anserina. All extracts showed similar, concentration-dependent free radical scavenging (DPPH) effect. Potentilla extracts, especially at lower concentration, decreased IL-6 production in myofibroblasts but the level of the cytokine was found to be stable in epithelial cells. IL-10 analysis revealed that P. argentea, D. rupestris, P. erecta extracts decrease cytokine level in myofibroblasts, while only when higher concentration were applied, decreased cytokine level produced by epithelial cells was found. F-actin filaments staining revealed that Potentilla extracts significantly influence on cellular cytoskeleton organization. Potentilla extracts influence on cells of human colon wall lining modulating the main features of them (viability

  12. Identification and manipulation of the pleuromutilin gene cluster from Clitopilus passeckerianus for increased rapid antibiotic production

    NASA Astrophysics Data System (ADS)

    Bailey, Andy M.; Alberti, Fabrizio; Kilaru, Sreedhar; Collins, Catherine M.; de Mattos-Shipley, Kate; Hartley, Amanda J.; Hayes, Patrick; Griffin, Alison; Lazarus, Colin M.; Cox, Russell J.; Willis, Christine L.; O’Dwyer, Karen; Spence, David W.; Foster, Gary D.

    2016-05-01

    Semi-synthetic derivatives of the tricyclic diterpene antibiotic pleuromutilin from the basidiomycete Clitopilus passeckerianus are important in combatting bacterial infections in human and veterinary medicine. These compounds belong to the only new class of antibiotics for human applications, with novel mode of action and lack of cross-resistance, representing a class with great potential. Basidiomycete fungi, being dikaryotic, are not generally amenable to strain improvement. We report identification of the seven-gene pleuromutilin gene cluster and verify that using various targeted approaches aimed at increasing antibiotic production in C. passeckerianus, no improvement in yield was achieved. The seven-gene pleuromutilin cluster was reconstructed within Aspergillus oryzae giving production of pleuromutilin in an ascomycete, with a significant increase (2106%) in production. This is the first gene cluster from a basidiomycete to be successfully expressed in an ascomycete, and paves the way for the exploitation of a metabolically rich but traditionally overlooked group of fungi.

  13. Identification and manipulation of the pleuromutilin gene cluster from Clitopilus passeckerianus for increased rapid antibiotic production

    PubMed Central

    Bailey, Andy M.; Alberti, Fabrizio; Kilaru, Sreedhar; Collins, Catherine M.; de Mattos-Shipley, Kate; Hartley, Amanda J.; Hayes, Patrick; Griffin, Alison; Lazarus, Colin M.; Cox, Russell J.; Willis, Christine L.; O’Dwyer, Karen; Spence, David W.; Foster, Gary D.

    2016-01-01

    Semi-synthetic derivatives of the tricyclic diterpene antibiotic pleuromutilin from the basidiomycete Clitopilus passeckerianus are important in combatting bacterial infections in human and veterinary medicine. These compounds belong to the only new class of antibiotics for human applications, with novel mode of action and lack of cross-resistance, representing a class with great potential. Basidiomycete fungi, being dikaryotic, are not generally amenable to strain improvement. We report identification of the seven-gene pleuromutilin gene cluster and verify that using various targeted approaches aimed at increasing antibiotic production in C. passeckerianus, no improvement in yield was achieved. The seven-gene pleuromutilin cluster was reconstructed within Aspergillus oryzae giving production of pleuromutilin in an ascomycete, with a significant increase (2106%) in production. This is the first gene cluster from a basidiomycete to be successfully expressed in an ascomycete, and paves the way for the exploitation of a metabolically rich but traditionally overlooked group of fungi. PMID:27143514

  14. 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.

  15. 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

  16. 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

  17. Rapid Identification of Candida Species and Other Clinically Important Yeast Species by Flow Cytometry†

    PubMed Central

    Page, Brent T.; Kurtzman, Cletus P.

    2005-01-01

    Two rapid diagnostic assays, utilizing two different Luminex flow cytometry methods, were developed for identification of clinically important ascomycetous yeast species. Direct hybridization and allele-specific primer extension methods were both successful in establishing a DNA-based assay that can rapidly and accurately identify Candida albicans, Candida krusei, Candida parapsilosis, Candida glabrata, and Candida tropicalis as well as other clinical species. The direct hybridization assay was designed to identify a total of 19 ascomycetous yeast species, and the allele-specific primer extension assay was designed to identify a total of 34 species. Probes were validated against 438 strains representing 303 species. From culture to identification, the allele-specific primer extension method takes 8 h and the direct hybridization method takes less than 5 h to complete. These assays represent comprehensive, rapid tests that are well suited for the clinical laboratory. PMID:16145099

  18. Molecular characterisation of fungal endophytic morphospecies associated with the indigenous forest tree, Theobroma gileri, in Ecuador.

    PubMed

    Thomas, Sarah E; Crozier, Jayne; Catherine Aime, M; Evans, Harry C; Holmes, Keith A

    2008-07-01

    Fungal endophytes were isolated from healthy stems and pods of Theobroma gileri, an alternative host of the frosty pod rot pathogen of cacao. Non-sporulating isolates were grouped into 46 different morphological species according to their colony morphology. Many of these morphospecies were assumed to be basidiomycetes and, therefore, were of particular interest. Basidiomycetous endophytes have received far less attention than ascomycetes and also have potential as biological control agents of the basidiomycetous pathogens of T. cacao: Moniliophthora roreri (frosty pod rot pathogen) and M. perniciosa (witches' broom disease). The morphospecies were further characterised by molecular analyses. Amplification of the nuLSU was undertaken for phylogenetic placement of these non-sporulating cultures and revealed a total of 31 different taxa of which 15 were basidiomycetes belonging to the class Agaricomycetes, and 16 ascomycetes primarily belonging to the Sordariomycetes.

  19. A year-round study on functional relationships of airborne fungi with meteorological factors

    NASA Astrophysics Data System (ADS)

    Li, De-Wei; Kendrick, Bryce

    1995-06-01

    Air sampling was conducted in Waterloo, Canada throughout 1992. Functional relationships between aeromycota and meteorological factors were analysed. The meteorological factors were, in descending order of importance: mean temperature, minimum temperature, maximum temperature, mean wind speed, relative humidity (RH), rain, maximum wind speed and snow. The most important airborne fungal propagules in descending order were: total fungal spores, unidentified Ascomycetes, Cladosporium, Coprinus, unidentified Basidiomycetes, Alternaria and unidentified fungi. Most airborne fungal taxa had highly significant relationship with temperature, but Aspergillus/Penicillium, hyphal fragments and Epicoccum did not. Epicoccum and hyphal fragments were positively associated with wind speed. In comparison with other airborne fungal taxa, Leptosphaeria and unidentified Ascomycetes were more closely correlated with rain and RH during the growing season.

  20. Genomic perspectives on the evolution of fungal entomopathogenicity in Beauveria bassiana

    PubMed Central

    Xiao, Guohua; Ying, Sheng-Hua; Zheng, Peng; Wang, Zheng-Liang; Zhang, Siwei; Xie, Xue-Qin; Shang, Yanfang; St. Leger, Raymond J.; Zhao, Guo-Ping; Wang, Chengshu; Feng, Ming-Guang

    2012-01-01

    The ascomycete fungus Beauveria bassiana is a pathogen of hundreds of insect species and is commercially produced as an environmentally friendly mycoinsecticide. We sequenced the genome of B. bassiana and a phylogenomic analysis confirmed that ascomycete entomopathogenicity is polyphyletic, but also revealed convergent evolution to insect pathogenicity. We also found many species-specific virulence genes and gene family expansions and contractions that correlate with host ranges and pathogenic strategies. These include B. bassiana having many more bacterial-like toxins (suggesting an unsuspected potential for oral toxicity) and effector-type proteins. The genome also revealed that B. bassiana resembles the closely related Cordyceps militaris in being heterothallic, although its sexual stage is rarely observed. A high throughput RNA-seq transcriptomic analysis revealed that B. bassiana could sense and adapt to different environmental niches by activating well-defined gene sets. The information from this study will facilitate further development of B. bassiana as a cost-effective mycoinsecticide. PMID:22761991

  1. 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

  2. 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 β-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

  3. Draft Genome Sequence of the Chloroperoxidase-Producing Fungus Caldariomyces fumago Woronichin DSM1256

    PubMed Central

    Pecyna, Marek Jan; Buchhaupt, Markus; Ullrich, René; Hofrichter, Martin

    2016-01-01

    We report here the draft genome sequence of the chloroperoxidase (EC 1.11.1.10)-producing ascomycete Caldariomyces fumago. Its genome was assembled into 511 contigs with a total size of 25 Mb. The G+C content is 51.4%, and 9,806 putative protein-coding genes were predicted. Eight heme-thiolate peroxidase genes, including two chloroperoxidase genes, were found. PMID:27491999

  4. 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

  5. A disseminated infection with the antifungal-multiresistant teleomorphic fungus Neocosmospora vasinfecta in a patient with acute B-lymphoblastic leukemia

    PubMed Central

    Gabriel, Frédéric; D’Almeida, Mahussi; Albert, Olivier; Fitton-Ouhabi, Valérie; Noël, Thierry; Accoceberry, Isabelle

    2013-01-01

    We report on a fatal invasive infection due to the ascomycetous fungus Neocosmospora vasinfecta, in a 20-year-old European patient suffering from an acute lymphoblastic leukemia. The infection could not be controlled by a bitherapy combining liposomal amphotericin B and voriconazole. This is the second case of disseminated infection reported with this unusual fungus, which develops under its teleomorphic state, is fully resistant to all systemic antifungals, and which is known to live in tropical countries. PMID:24432214

  6. Cerebral Aspergillosis Caused by Neosartorya hiratsukae, Brazil

    PubMed Central

    Kallas, Esper G.; Godoy, Patricio; Karenina, Anna; Gené, Josepa; Stchigel, Alberto; Colombo, Arnaldo Lopes

    2002-01-01

    We report the first case of infection by Neosartorya hiratsukae, an ascomycete in which the conidial state resembles Aspergillus fumigatus. The fungus caused a brain infection in a Brazilian woman, who died despite itraconazole treatment. Diagnosis was established by direct microscopic examination, computed tomographic scan, and magnetic resonance imaging of the brain, and repeated cultures from the lesions. The in vitro antifungal susceptibility of the isolate is provided. PMID:12194781

  7. [Two cases of fungal infection of nails with participation of Cryptendoxyla hypophloia].

    PubMed

    Lysková, P; Hubka, V; Navrátilová, P; Kolařík, M; Skořepová, M

    2014-03-01

    Reported are two cases of suspected onychomycosis with participation of Cryptendoxyla hypophloia. The species C. hypophloia have not been isolated from human and animal clinical material yet. It is a rarely reported cleistothecial ascomycete that has been found to be naturally present on cellulose-rich materials. Its strains tested in a laboratory demonstrated very good susceptibility to terbinafine. The identification of isolates was verified based on rDNA sequencing and by comparison with C. hypophloia ex-type strain.

  8. Onychomycosis due to Chaetomium globosum with yellowish black discoloration and periungual inflammation.

    PubMed

    Shi, Dongmei; Lu, Guixia; Mei, Huan; de Hoog, G Sybren; Zheng, Hailin; Liang, Guanzhao; Shen, Yongnian; Li, Tianhang; Liu, Weida

    2016-09-01

    Onychomycosis is usually caused by dermatophytes, although also other filamentous and yeast-like fungi are associated with nail invasion. Chaetomium is an environmental genus of ascomycetes exhibiting a certain degree of extremotolerance. We report the first case of onychomycosis in a 46-year-old woman in China caused by Chaetomium globosum. The patient showed yellowish black discoloration with periungual inflammation on the left first toenail. We confirmed the causative agent, C. globosum, by KOH mount, culture, micromorphology and DNA sequence analysis.

  9. 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.

  10. Small Subunits of Serine Palmitoyltransferase (ssSPTs) and Their Physiological Roles

    DTIC Science & Technology

    2014-02-12

    blast homology searches of Tsc3p against the human genome showed no candidate homologs. However, recently two functional orthologs of Tsc3p, the small...ssSPTs in Schizosaccharomyces pombe   INTRODUCTION: Schizosaccharomyces pombe forms a major clade of the ‘Ascomycete fungi ’ but it is believed...homology search against the C. elegans genome database, using human ssSPTa as the query sequence. Blast analysis yielded one questionable homolog

  11. Genome Sequence of the Food Spoilage Yeast Zygosaccharomyces bailii CLIB 213T.

    PubMed

    Galeote, Virginie; Bigey, Frédéric; Devillers, Hugo; Neuvéglise, Cécile; Dequin, Sylvie

    2013-08-22

    The ascomycetous yeast Zygosaccharomyces bailii is one of the most problematic spoilage yeasts in food and beverage industries, due to its exceptional resistance to various stresses. A better understanding of the molecular mechanisms underlying these stress resistance phenotypes might help develop strategies to improve food quality. Thus, we determined and annotated the genome sequence of the strain Z. bailii CLIB 213(T) (= CBS 680).

  12. Camarosporium arezzoensis on Cytisus sp., an addition to sexual state of Camarosporium sensu stricto.

    PubMed

    Tibpromma, Saowaluck; Wijayawardene, Nalin N; Manamgoda, Dimuthu S; Boonmee, Saranyaphat; Wanasinghe, Dhanushka N; Camporesi, Erio; Yang, Jun-Bo; Hyde, Kevin D

    2016-01-01

    During a study of saprobic fungi from Bagno di Cetica Province, Italy, we collected a pleosporoid ascomycete on stems of Cytisus sp. In morphology, our collection is similar to Cucurbitaria species, but molecular analysis of SSU, LSU and ITS genes reveals it can be referred to Camarosporium. In this study we compare all other Cucurbitaria species from Cytisus sp. and based on both morphology and molecular data, we introduce our collection as a new species in Camarosporium viz. C. arezzoensis.

  13. Slippery Scar: A New Mushroom Disease in Auricularia polytricha

    PubMed Central

    Sun, Jie

    2012-01-01

    A new disease, the slippery scar, was investigated in cultivated bags of Auricularia polytricha. This fungus was isolated from the infected mycelia of cultivated bags. Based on morphological observation, rDNA-internal transcribed spacer and 18S sequence analysis, this pathogen was identified as the Ascomycete Scytalidium lignicola. According to Koch's Postulation, the pathogenicity of S. lignicola to the mycelia of A. polytricha was confirmed. The parasitism of this fungus on mushroom mycelia in China has not been reported before. PMID:22870056

  14. Xyloglucan breakdown by endo-xyloglucanase family 74 from Aspergillus fumigatus.

    PubMed

    Damasio, André Ricardo de Lima; Rubio, Marcelo Ventura; Gonçalves, Thiago Augusto; Persinoti, Gabriela Felix; Segato, Fernando; Prade, Rolf Alexander; Contesini, Fabiano Jares; de Souza, Amanda Pereira; Buckeridge, Marcos Silveira; Squina, Fabio Marcio

    2017-04-01

    Xyloglucan is the most abundant hemicellulose in primary walls of spermatophytes except for grasses. Xyloglucan-degrading enzymes are important in lignocellulosic biomass hydrolysis because they remove xyloglucan, which is abundant in monocot-derived biomass. Fungal genomes encode numerous xyloglucanase genes, belonging to at least six glycoside hydrolase (GH) families. GH74 endo-xyloglucanases cleave xyloglucan backbones with unsubstituted glucose at the -1 subsite or prefer xylosyl-substituted residues in the -1 subsite. In this work, 137 GH74-related genes were detected by examining 293 Eurotiomycete genomes and Ascomycete fungi contained one or no GH74 xyloglucanase gene per genome. Another interesting feature is that the triad of tryptophan residues along the catalytic cleft was found to be widely conserved among Ascomycetes. The GH74 from Aspergillus fumigatus (AfXEG74) was chosen as an example to conduct comprehensive biochemical studies to determine the catalytic mechanism. AfXEG74 has no CBM and cleaves the xyloglucan backbone between the unsubstituted glucose and xylose-substituted glucose at specific positions, along the XX motif when linked to regions deprived of galactosyl branches. It resembles an endo-processive activity, which after initial random hydrolysis releases xyloglucan-oligosaccharides as major reaction products. This work provides insights on phylogenetic diversity and catalytic mechanism of GH74 xyloglucanases from Ascomycete fungi.

  15. Comparative genomics of biotechnologically important yeasts

    PubMed Central

    Riley, Robert; Haridas, Sajeet; Wolfe, Kenneth H.; Lopes, Mariana R.; Hittinger, Chris Todd; Göker, Markus; Salamov, Asaf A.; Wisecaver, Jennifer H.; Long, Tanya M.; Aerts, Andrea L.; Barry, Kerrie W.; Choi, Cindy; Clum, Alicia; Coughlan, Aisling Y.; Deshpande, Shweta; Douglass, Alexander P.; Hanson, Sara J.; Klenk, Hans-Peter; LaButti, Kurt M.; Lapidus, Alla; Lindquist, Erika A.; Lipzen, Anna M.; Meier-Kolthoff, Jan P.; Ohm, Robin A.; Otillar, Robert P.; Pangilinan, Jasmyn L.; Peng, Yi; Rosa, Carlos A.; Scheuner, Carmen; Sibirny, Andriy A.; Slot, Jason C.; Stielow, J. Benjamin; Sun, Hui; Kurtzman, Cletus P.; Blackwell, Meredith; Grigoriev, Igor V.

    2016-01-01

    Ascomycete yeasts are metabolically diverse, with great potential for biotechnology. Here, we report the comparative genome analysis of 29 taxonomically and biotechnologically important yeasts, including 16 newly sequenced. We identify a genetic code change, CUG-Ala, in Pachysolen tannophilus in the clade sister to the known CUG-Ser clade. Our well-resolved yeast phylogeny shows that some traits, such as methylotrophy, are restricted to single clades, whereas others, such as l-rhamnose utilization, have patchy phylogenetic distributions. Gene clusters, with variable organization and distribution, encode many pathways of interest. Genomics can predict some biochemical traits precisely, but the genomic basis of others, such as xylose utilization, remains unresolved. Our data also provide insight into early evolution of ascomycetes. We document the loss of H3K9me2/3 heterochromatin, the origin of ascomycete mating-type switching, and panascomycete synteny at the MAT locus. These data and analyses will facilitate the engineering of efficient biosynthetic and degradative pathways and gateways for genomic manipulation. PMID:27535936

  16. Capnodiaceae

    PubMed Central

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

    2012-01-01

    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

  17. Estimating the Phanerozoic history of the Ascomycota lineages: combining fossil and molecular data.

    PubMed

    Beimforde, Christina; Feldberg, Kathrin; Nylinder, Stephan; Rikkinen, Jouko; Tuovila, Hanna; Dörfelt, Heinrich; Gube, Matthias; Jackson, Daniel J; Reitner, Joachim; Seyfullah, Leyla J; Schmidt, Alexander R

    2014-09-01

    The phylum Ascomycota is by far the largest group in the fungal kingdom. Ecologically important mutualistic associations such as mycorrhizae and lichens have evolved in this group, which are regarded as key innovations that supported the evolution of land plants. Only a few attempts have been made to date the origin of Ascomycota lineages by using molecular clock methods, which is primarily due to the lack of satisfactory fossil calibration data. For this reason we have evaluated all of the oldest available ascomycete fossils from amber (Albian to Miocene) and chert (Devonian and Maastrichtian). The fossils represent five major ascomycete classes (Coniocybomycetes, Dothideomycetes, Eurotiomycetes, Laboulbeniomycetes, and Lecanoromycetes). We have assembled a multi-gene data set (18SrDNA, 28SrDNA, RPB1 and RPB2) from a total of 145 taxa representing most groups of the Ascomycota and utilized fossil calibration points solely from within the ascomycetes to estimate divergence times of Ascomycota lineages with a Bayesian approach. Our results suggest an initial diversification of the Pezizomycotina in the Ordovician, followed by repeated splits of lineages throughout the Phanerozoic, and indicate that this continuous diversification was unaffected by mass extinctions. We suggest that the ecological diversity within each lineage ensured that at least some taxa of each group were able to survive global crises and rapidly recovered.

  18. Detecting morphological convergence in true fungi, using 18S rRNA gene sequence data.

    PubMed

    Berbee, M L; Taylor, J W

    1992-01-01

    For the true fungi, phylogenetic relationships inferred from 18S ribosomal DNA sequence data agree with morphology when (1) the fungi exhibit diagnostic morphological characters, (2) the sequence-based phylogenetic groups are statistically supported, and (3) the ribosomal DNA evolves at roughly the same rate in the lineages being compared. 18S ribosomal RNA gene sequence data and biochemical data provide a congruent definition of true fungi. Sequence data support the traditional fungal subdivisions Ascomycotina and Basidiomycotina. In conflict with morphology, some zygomycetes group with chytrid water molds rather than with other terrestrial fungi, possibly owing to unequal rates of nucleotide substitutions among zygomycete lineages. Within the ascomycetes, the taxonomic consequence of simple or reduced morphology has been a proliferation of mutually incongruent classification systems. Sequence data provide plausible resolution of relationships for some cases where reduced morphology has created confusion. For example, phylogenetic trees from rDNA indicate that those morphologically simple ascomycetes classified as yeasts are polyphyletic and that forcible spore discharge was lost convergently from three lineages of ascomycetes producing flask-like fruiting bodies.

  19. Diversity of fungi in creosote-treated crosstie wastes and their resistance to polycyclic aromatic hydrocarbons.

    PubMed

    Kim, Min-Ji; Lee, Hwanhwi; Choi, Yong-Seok; Kim, Gyu-Hyeok; Huh, Na-Yoon; Lee, Sangjoon; Lim, Young Woon; Lee, Sung-Suk; Kim, Jae-Jin

    2010-05-01

    This study was conducted to generate information regarding the diversity of fungi inhabiting creosote-treated wood in a storage yard for crosstie wastes in Gwangmyeong, Korea. Additionally, the resistance to polycyclic aromatic hydrocarbons (PAHs) of indigenous fungi that mainly occupy creosote-treated wood was evaluated. We isolated fungi from the surface and inner area of crosstie wastes and identified them using a combination of traditional methods and molecular techniques. Overall, 179 isolates including 47 different species were isolated from 240 sampling sites. The identified fungal species included 23 ascomycetes, 19 basidiomycetes, and 5 zygomycetes. Three species, Alternaria alternata, Irpex lacteus, and Rhizomucor variabilis, were the most frequently isolated ascomycetes, basidiomycetes, and zygomycetes, respectively. The results of this study showed that there was a large difference in the fungal diversity between the surface and the inner area. Additionally, zygomycetes and ascomycetes were found to have a greater tolerance to PAHs than basidiomycetes. However, two basidiomycetes, Heterobasidion annosum and Schizophyllum commune, showed very high resistance to PAHs, even in response to the highest concentration (1,000 ppm), which indicates that these species may play a role in the degradation of PAHs.

  20. Cell wall construction in Saccharomyces cerevisiae.

    PubMed

    Klis, Frans M; Boorsma, Andre; De Groot, Piet W J

    2006-02-01

    In this review, we discuss new insights in cell wall architecture and cell wall construction in the ascomycetous yeast Saccharomyces cerevisiae. Transcriptional profiling studies combined with biochemical work have provided ample evidence that the cell wall is a highly adaptable organelle. In particular, the protein population that is anchored to the stress-bearing polysaccharides of the cell wall, and forms the interface with the outside world, is highly diverse. This diversity is believed to play an important role in adaptation of the cell to environmental conditions, in growth mode and in survival. Cell wall construction is tightly controlled and strictly coordinated with progression of the cell cycle. This is reflected in the usage of specific cell wall proteins during consecutive phases of the cell cycle and in the recent discovery of a cell wall integrity checkpoint. When the cell is challenged with stress conditions that affect the cell wall, a specific transcriptional response is observed that includes the general stress response, the cell wall integrity pathway and the calcineurin pathway. This salvage mechanism includes increased expression of putative cell wall assemblases and some potential cross-linking cell wall proteins, and crucial changes in cell wall architecture. We discuss some more enzymes involved in cell wall construction and also potential inhibitors of these enzymes. Finally, we use both biochemical and genomic data to infer that the architectural principles used by S. cerevisiae to build its cell wall are also used by many other ascomycetous yeasts and also by some mycelial ascomycetous fungi.

  1. Structure-Activity Relationship of α Mating Pheromone from the Fungal Pathogen Fusarium oxysporum.

    PubMed

    Vitale, Stefania; Partida-Hanon, Angélica; Serrano, Soraya; Martínez-Del-Pozo, Álvaro; Di Pietro, Antonio; Turrà, David; Bruix, Marta

    2017-03-03

    During sexual development ascomycete fungi produce two types of peptide pheromones termed a and α. The α pheromone from the budding yeast Saccharomyces cerevisiae, a 13-residue peptide that elicits cell cycle arrest and chemotropic growth, has served as paradigm for the interaction of small peptides with their cognate G protein-coupled receptors. However, no structural information is currently available for α pheromones from filamentous ascomycetes, which are significantly shorter and share almost no sequence similarity with the S. cerevisiae homolog. High resolution structure of synthetic α-pheromone from the plant pathogenic ascomycete Fusarium oxysporum revealed the presence of a central β-turn resembling that of its yeast counterpart. Disruption of the-fold by d-alanine substitution of the conserved central Gly(6)-Gln(7) residues or by random sequence scrambling demonstrated a crucial role for this structural determinant in chemoattractant activity. Unexpectedly, the growth inhibitory effect of F. oxysporum α-pheromone was independent of the cognate G protein-coupled receptors Ste2 and of the central β-turn but instead required two conserved Trp(1)-Cys(2) residues at the N terminus. These results indicate that, despite their reduced size, fungal α-pheromones contain discrete functional regions with a defined secondary structure that regulate diverse biological processes such as polarity reorientation and cell division.

  2. 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 ΔSmkin3/ΔSmkin24 displayed the combined phenotypes of each single-deletion strain. PMID:26418262

  3. Soil-inhabiting fungal community composition as qualitative indicator of C metabolism processes

    NASA Astrophysics Data System (ADS)

    Manici, L.; Ciavatta, C.; Caputo, F.

    2009-04-01

    Although fungi represent the greater part of soil microbial biomass, they play an important role in macro-aggregate formation and their carbon (C) assimilation efficiency is markedly higher than that of bacteria (Bailey et al., 2002), they have not yet been widely used as soil biological indicators. The reason is mainly due to the difficulties in application of molecular analysis tools due to limited availability of reference sequence of fungal strains in DNA database and to the low concentration of fungal DNA in soil and in isolating, enumerating and identifying groups of fungi differing for their functioning in soil and for biological characteristics. The presence of Ascomycetes and Basidiomycetes as the two main groups of soil-inhabiting fungi were investigated in four different cropping systems. The soil DNA of soil samples coming from twenty sites (five sites for each system), collected in two cropping systems in northern (soil organic matter - SOM content varying from 0.8 to 1.4 %) and two in southern Italy (SOM from 1.4 to 2.3%), was amplified using Ascomycete-specific primer ITS1F - ITS4A (Larena et al., 1999) and Basidiomycete-specific primer ITS1F -ITS4B (Gardes and Bruns, 1993). On the basis of soil DNA amplified with specific primers, Ascomycetes were much more represented than Basidiomycetes in the cultivated top soil. Basidiomycetes are usually reported to account for more than half of the fungal biomass in undisturbed soils. However the low ratio of Basidiomycete DNA to soil fungal DNA observed in this study could be a feature of soil fungal communities in arable soil affected by desertification problems as those of some Italian cropping systems mainly in Mediterranean area. This phenomenon could be due to soil tillage, which is well known to deeply reduce fungal biomass and to continuous incorporation into the soil of herbaceous crop residues. In fact, Ascomycetes decompose holocellulose in preference to lignin (Oslko & Takeda, 2002) and their

  4. Four marine-derived fungi for bioremediation of raw textile mill effluents.

    PubMed

    Verma, Ashutosh Kumar; Raghukumar, Chandralata; Verma, Pankaj; Shouche, Yogesh S; Naik, Chandrakant Govind

    2010-04-01

    Textile dye effluents pose environmental hazards because of color and toxicity. Bioremediation of these has been widely attempted. However, their widely differing characteristics and high salt contents have required application of different microorganisms and high dilutions. We report here decolorization and detoxification of two raw textile effluents, with extreme variations in their pH and dye composition, used at 20-90% concentrations by each of the four marine-derived fungi. Textile effluent A (TEA) contained an azo dye and had a pH of 8.9 and textile effluent B (TEB) with a pH of 2.5 contained a mixture of eight reactive dyes. The fungi isolated from mangroves and identified by 18S and ITS sequencing corresponded to two ascomycetes and two basidiomycetes. Each of these fungi decolorized TEA by 30-60% and TEB by 33-80% used at 20-90% concentrations and salinity of 15 ppt within 6 days. This was accompanied by two to threefold reduction in toxicity as measured by LC(50) values against Artemia larvae and 70-80% reduction in chemical oxygen demand and total phenolics. Mass spectrometric scan of effluents after fungal treatment revealed degradation of most of the components. The ascomycetes appeared to remove color primarily by adsorption, whereas laccase played a major role in decolorization by basidiomycetes. A process consisting of a combination of sorption by fungal biomass of an ascomycete and biodegradation by laccase from a basidiomycete was used in two separate steps or simultaneously for bioremediation of these two effluents.

  5. Yeast diversity associated with invasive Dendroctonus valens killing Pinus tabuliformis in China using culturing and molecular methods.

    PubMed

    Lou, Qiao-Zhe; Lu, Min; Sun, Jiang-Hua

    2014-08-01

    Bark beetle-associated yeasts are much less studied than filamentous fungi, yet they are also considered to play important roles in beetle nutrition, detoxification, and chemical communication. The red turpentine beetle, Dendroctonus valens, an invasive bark beetle introduced from North America, became one of the most destructive pests in China, having killed more than 10 million Pinus tabuliformis as well as other pine species. No investigation of yeasts associated with this bark beetle in its invaded ranges has been conducted so far. The aim of this study was to assess the diversity of yeast communities in different microhabitats and during different developmental stages of Den. valens in China using culturing and denaturing gradient gel electrophoresis (DGGE) approaches and to compare the yeast flora between China and the USA. The yeast identity was confirmed by sequencing the D1/D2 domain of LSU ribosomal DNA (rDNA). In total, 21 species (13 ascomycetes and eight basidiomycetes) were detected by culturing method, and 12 species (11 ascomycetes and one basidiomycetes) were detected by molecular methods from China. The most frequent five species in China were Candida piceae (Ogataea clade), Cyberlindnera americana, Candida oregonensis (Metschnikowia clade), Candida nitratophila (Ogataea clade) and an undescribed Saccharomycopsis sp., detected by both methods. Seven species were exclusively detected by DGGE. Ca. oregonensis (Metschnikowia clade) was the most frequently detected species by DGGE method. Eight species (all were ascomycetes) from the USA were isolated; seven of those were also found in China. We found significant differences in yeast total abundance as well as community composition between different developmental stages and significant differences between the surface and the gut. The frass yeast community was more similar to that of Den. valens surface or larvae than to the community of the gut or adults. Possible functions of the yeast associates are

  6. Yeasts in malting, with special emphasis on Wickerhamomyces anomalus (synonym Pichia anomala).

    PubMed

    Laitila, Arja; Sarlin, Tuija; Raulio, Mari; Wilhelmson, Annika; Kotaviita, Erja; Huttunen, Timo; Juvonen, Riikka

    2011-01-01

    Malted barley is a major raw material of beer, as well as distilled spirits and several food products. The production of malt (malting) exploits the biochemical reactions of a natural process, grain germination. In addition to germinating grain, the malting process includes another metabolically active component: a diverse microbial community that includes various types of bacteria and fungi. Therefore, malting can be considered as a complex ecosystem involving two metabolically active groups. Yeasts and yeast-like fungi are an important part of this ecosystem, but previously the significance of yeasts in malting has been largely underestimated. Characterization and identification of yeasts in industrial processes revealed 25 ascomycetous yeasts belonging to 10 genera, and 18 basidiomycetous yeasts belonging to 7 genera. In addition, two ascomycetous yeast-like fungi belonging to the genera Aureobasidium and Exophiala were commonly detected. Yeasts and yeast-like fungi produced extracellular hydrolytic enzymes with a potentially positive contribution to the malt enzyme spectrum. Several ascomycetous yeast strains showed strong antagonistic activity against field and storage moulds, Wickerhamomyces anomalus (synonym Pichia anomala) being the most effective species. Malting studies revealed that W. anomalus VTT C-04565 effectively restricted Fusarium growth and hydrophobin production during malting and prevented beer gushing. In order to broaden the antimicrobial spectrum and to improve malt brewhouse performance, W. anomalus could be combined with other starter cultures such as Lactobacillus plantarum. Well-characterized microbial mixtures consisting of barley and malt-derived microbes open up several possibilities to improve malt properties and to ensure the safety of the malting process.

  7. 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

  8. 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.

  9. The Metarhizium anisopliae trp1 gene: cloning and regulatory analysis.

    PubMed

    Staats, Charley Christian; Silva, Marcia Suzana Nunes; Pinto, Paulo Marcos; Vainstein, Marilene Henning; Schrank, Augusto

    2004-07-01

    The trp1 gene from the entomopathogenic fungus Metarhizium anisopliae, cloned by heterologous hybridization with the plasmid carrying the trpC gene from Aspergillus nidulans, was sequence characterized. The predicted translation product has the conserved catalytic domains of glutamine amidotransferase (G domain), indoleglycerolphosphate synthase (C domain), and phosphoribosyl anthranilate isomerase (F domain) organized as NH2-G-C-F-COOH. The ORF is interrupted by a single intron of 60 nt that is position conserved in relation to trp genes from Ascomycetes and length conserved in relation to Basidiomycetes species. RT-PCR analysis suggests constitutive expression of trp1 gene in M. anisopliae.

  10. 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.

  11. Mildew-Omics: How Global Analyses Aid the Understanding of Life and Evolution of Powdery Mildews

    PubMed Central

    Bindschedler, Laurence V.; Panstruga, Ralph; Spanu, Pietro D.

    2016-01-01

    The common powdery mildew plant diseases are caused by ascomycete fungi of the order Erysiphales. Their characteristic life style as obligate biotrophs renders functional analyses in these species challenging, mainly because of experimental constraints to genetic manipulation. Global large-scale (“-omics”) approaches are thus particularly valuable and insightful for the characterisation of the life and evolution of powdery mildews. Here we review the knowledge obtained so far from genomic, transcriptomic and proteomic studies in these fungi. We consider current limitations and challenges regarding these surveys and provide an outlook on desired future investigations on the basis of the various –omics technologies. PMID:26913042

  12. A Statistical Evaluation of Methods of In-Vitro Growth Assessment for Phyllosticta citricarpa: Average Colony Diameter vs. Area

    PubMed Central

    Christman, Mary C.; Roberts, Pamela D.

    2017-01-01

    Fungal growth inhibition on solid media has been historically measured and calculated based on the average of perpendicular diameter measurements of growth on fungicide amended media. We investigated the sensitivity of the calculated area (DA) and the measured area (MA) for assessing fungicide growth inhibition of the ascomycete, Phyllosticta citricarpa on solid media. Both the calculated, DA and the actual measured area, MA were adequate for distinguishing significant treatment effects of fungicide on fungal growth, however MA was more sensitive at identifying significant differences between the controls and fungicide concentrations below 5 ppm. PMID:28125679

  13. Mycorrhizal Formation and Diversity of Endophytic Fungi in Hair Roots of Vaccinium oldhamii Miq. in Japan

    PubMed Central

    Baba, Takashi; Hirose, Dai; Sasaki, Nobumitsu; Watanabe, Naoaki; Kobayashi, Nobuo; Kurashige, Yuji; Karimi, Fraidoon; Ban, Takuya

    2016-01-01

    The root diameters as well as colonization and diversity of the root-associating fungi of Vaccinium oldhamii Miq. were investigated in order to obtain information on their mycorrhizal properties. The distal regions of roots had typical hair roots with diameters of less than 100 μm. Ericoid mycorrhizal fungi (ErMF) and dark septate endophytes (DSE) were frequently observed in the roots. Ascomycetes, particularly helotialean fungi, appeared to be dominant among the endophytic fungi of V. oldhamii roots. Furthermore, Rhizoscyphus ericae (Read) Zhuang & Korf and Oidiodendron maius Barron known as ErMF were detected more frequently than other fungal species. PMID:27297892

  14. Large Scale Sequencing of Dothideomycetes Provides Insights into Genome Evolution and Adaptation

    SciTech Connect

    Haridas, Sajeet; Crous, Pedro; Binder, Manfred; Spatafora, Joseph; Grigoriev, Igor

    2015-03-16

    Dothideomycetes is the largest and most diverse class of ascomycete fungi with 23 orders 110 families, 1300 genera and over 19,000 known species. We present comparative analysis of 70 Dothideomycete genomes including over 50 that we sequenced and are as yet unpublished. This extensive sampling has almost quadrupled the previous study of 18 species and uncovered a 10 fold range of genome sizes. We were able to clarify the phylogenetic positions of several species whose origins were unclear in previous morphological and sequence comparison studies. We analyzed selected gene families including proteases, transporters and small secreted proteins and show that major differences in gene content is influenced by speciation.

  15. Marine mycoflora in backwater ecosystem of Kerala, India.

    PubMed

    Nambiar, Gayatri R; Raveendran, K

    2009-09-01

    Back water system of Kerala is well known for its fertility. Fungi play a vital role in detritus decomposition, nutrient cycling and energy flow in marine food web including backwater ecosystem. Present investigation on the diversity of marine fungi from two back waters of Kerala resulted in the isolation of 20 marine fungi. These include 11 Ascomycetes, 1 Basidiomycete and 8 Mitosporic fungi. In terms of percent frequency of occurrence the most common species obtained were Aniptodera chesapeakensis, Verruculina enalia, Savoryella lignicola and Clavatospora bulbosa. Ascochyta sp. was represented by only a single isolate.

  16. Metabolites from nematophagous fungi and nematicidal natural products from fungi as alternatives for biological control. Part II: metabolites from nematophagous basidiomycetes and non-nematophagous fungi.

    PubMed

    Degenkolb, Thomas; Vilcinskas, Andreas

    2016-05-01

    In this second section of a two-part mini-review article, we introduce 101 further nematicidal and non-nematicidal secondary metabolites biosynthesized by nematophagous basidiomycetes or non-nematophagous ascomycetes and basidiomycetes. Several of these compounds have promising nematicidal activity and deserve further and more detailed analysis. Thermolides A and B, omphalotins, ophiobolins, bursaphelocides A and B, illinitone A, pseudohalonectrins A and B, dichomitin B, and caryopsomycins A-C are excellent candidates or lead compounds for the development of biocontrol strategies for phytopathogenic nematodes. Paraherquamides, clonostachydiol, and nafuredins offer promising leads for the development of formulations against the intestinal nematodes of ruminants.

  17. Taming a wild beast: Developing molecular tools and new methods to understand the biology of Zymoseptoria tritici.

    PubMed

    Talbot, Nicholas J

    2015-06-01

    Septoria blotch of wheat is one of the world's most serious plant diseases, which is difficult to control due to the absence of durable host resistance and the increasing frequency of fungicide-resistance. The ascomycete fungus that causes the disease, Zymoseptoria tritici, has been very challenging to study. This special issue of Fungal Genetics and Biology showcases an integrated approach to method development and the innovation of new molecular tools to study the biology of Z. tritici. When considered together, these new methods will have a rapid and dramatic effect on our ability to combat this significant disease.

  18. Genetic conversion of a fungal plant pathogen to a non-pathogenic, endophytic mutualist

    USGS Publications Warehouse

    Freeman, Stanley; Rodriguez, Rusty J.

    1993-01-01

    The filamentous fungal ascomycete Colletotrichum magna causes anthracnose in cucurbit plants. Isolation of a nonpathogenic mutant of this species (path-1) resulted in maintained wild-type levels of in vitro sporulation, spore adhesion, appressorial formation, and infection. Path-1 grew throughout host tissues as an endophyte and retained the wild-type host range, which indicates that the genetics involved in pathogenicity and host specificity are distinct. Prior infection with path-1 protected plants from disease caused by Colletotrichum and Fusarium.Genetic analysis of a cross between path-1 and wild-type strains indicated mutation of a single locus.

  19. Mycorrhizal Formation and Diversity of Endophytic Fungi in Hair Roots of Vaccinium oldhamii Miq. in Japan.

    PubMed

    Baba, Takashi; Hirose, Dai; Sasaki, Nobumitsu; Watanabe, Naoaki; Kobayashi, Nobuo; Kurashige, Yuji; Karimi, Fraidoon; Ban, Takuya

    2016-06-25

    The root diameters as well as colonization and diversity of the root-associating fungi of Vaccinium oldhamii Miq. were investigated in order to obtain information on their mycorrhizal properties. The distal regions of roots had typical hair roots with diameters of less than 100 μm. Ericoid mycorrhizal fungi (ErMF) and dark septate endophytes (DSE) were frequently observed in the roots. Ascomycetes, particularly helotialean fungi, appeared to be dominant among the endophytic fungi of V. oldhamii roots. Furthermore, Rhizoscyphus ericae (Read) Zhuang & Korf and Oidiodendron maius Barron known as ErMF were detected more frequently than other fungal species.

  20. Multi-omics analysis reveals regulators of the response to nitrogen limitation in Yarrowia lipolytica

    SciTech Connect

    Pomraning, Kyle R.; Kim, Young -Mo; Nicora, Carrie D.; Chu, Rosalie K.; Bredeweg, Erin L.; Purvine, Samuel O.; Hu, Dehong; Metz, Thomas O.; Baker, Scott E.

    2016-02-25

    Yarrowia lipolytica is an oleaginous ascomycete yeast that stores lipids in response to limitation of nitrogen. Furthermore, while the enzymatic pathways responsible for neutral lipid accumulation in Y. lipolytica are well characterized, regulation of these pathways has received little attention. We therefore sought to characterize the response to nitrogen limitation at system-wide levels, including the proteome, phosphoproteome and metabolome, to better understand how this organism regulates and controls lipid metabolism and to identify targets that may be manipulated to improve lipid yield.

  1. Multi-omics analysis reveals regulators of the response to nitrogen limitation in Yarrowia lipolytica

    DOE PAGES

    Pomraning, Kyle R.; Kim, Young -Mo; Nicora, Carrie D.; ...

    2016-02-25

    Yarrowia lipolytica is an oleaginous ascomycete yeast that stores lipids in response to limitation of nitrogen. Furthermore, while the enzymatic pathways responsible for neutral lipid accumulation in Y. lipolytica are well characterized, regulation of these pathways has received little attention. We therefore sought to characterize the response to nitrogen limitation at system-wide levels, including the proteome, phosphoproteome and metabolome, to better understand how this organism regulates and controls lipid metabolism and to identify targets that may be manipulated to improve lipid yield.

  2. Wild type and mutants of the HET-s(218-289) prion show different flexibility at fibrillar ends: a simulation study.

    PubMed

    Friedman, Ran; Caflisch, Amedeo

    2014-03-01

    The C-terminal segment (residues 218-289) of the HET-s protein of the filamentous fungus Podosporina anserina is a prion-forming domain. The structural model of the HET-s(218-289) amyloid fibril based on solid-state nuclear magnetic resonance (NMR) restraints shows a β solenoid topology which is comprised of a β-sheet core and interconnecting loops. For the single-point mutants Phe286Ala and Trp287Ala, slower aggregation rates in vitro and loss of prionic infectivity have been reported recently. Here we have used molecular dynamics to compare the flexibility of the mutants and wild type. The simulations, initiated from a trimeric aggregate extracted from the NMR structural model, show structural stability on a 100-ns time scale for wild type and mutants. Analysis of the fluctuations along the simulations reveals that the mutants are less flexible than the wild type in the C-terminal segment at only one of the two external monomers. Analysis of interaction energy and buried accessible surface indicates that residue Phe286 in particular is stabilized in the Trp287Ala mutant. The simulation results provide an atomistic explanation of the suggestion (based on indirect experimental evidence) that flexibility at the protofibril end(s) is required for fibril elongation. Moreover, they provide further evidence that the growth of the HET-s amyloid fibril is directional.

  3. Communities of endophytic sebacinales associated with roots of herbaceous plants in agricultural and grassland ecosystems are dominated by Serendipita herbamans sp. nov.

    PubMed

    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.

  4. Microsatellites identify depredated waterfowl remains from glaucous gull stomachs

    USGS Publications Warehouse

    Scribner, K.T.; Bowman, Timothy 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.

  5. 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

  6. A naturally occurring repeat protein with high internal sequence identity defines a new class of TPR-like proteins

    PubMed Central

    Marold, Jacob D.; Kavran, Jennifer M.; Bowman, Gregory D.; Barrick, Doug

    2016-01-01

    SUMMARY Linear repeat proteins often have high structural similarity and low (~25%) pairwise sequence identities (PSI) among modules. We identified a unique P. anserina (Pa) sequence with tetratricopeptide repeat (TPR) homology, which contains longer (42 residue) repeats (42PRs) with an average PSI >91%. We determined the crystal structure of five tandem Pa 42PRs to 1.6Å, and examined the stability and solution properties of constructs containing three to six Pa 42PRs. Compared to 34-residue TPRs (34PRs), Pa 42PRs have a one-turn extension of each helix, and bury more surface area. Unfolding transitions shift to higher denaturant concentration and become sharper as repeats are added. Fitted Ising models show Pa 42PRs to be more cooperative than consensus 34PRs, with increased magnitudes of intrinsic and interfacial free energies. These results demonstrate the tolerance of the TPR motif to length variation, and provide a basis to understand the effects of helix length on intrinsic/interfacial stability. PMID:26439765

  7. Comparative genomic analyses of the human fungal pathogens Coccidioides and their relatives

    PubMed Central

    Sharpton, Thomas J.; Stajich, Jason E.; Rounsley, Steven D.; Gardner, Malcolm J.; Wortman, Jennifer R.; Jordar, Vinita S.; Maiti, Rama; Kodira, Chinnappa D.; Neafsey, Daniel E.; Zeng, Qiandong; Hung, Chiung-Yu; McMahan, Cody; Muszewska, Anna; Grynberg, Marcin; Mandel, M. Alejandra; Kellner, Ellen M.; Barker, Bridget M.; Galgiani, John N.; Orbach, Marc J.; Kirkland, Theo N.; Cole, Garry T.; Henn, Matthew R.; Birren, Bruce W.; Taylor, John W.

    2009-01-01

    While most Ascomycetes tend to associate principally with plants, the dimorphic fungi Coccidioides immitis and Coccidioides posadasii are primary pathogens of immunocompetent mammals, including humans. Infection results from environmental exposure to Coccidiodies, which is believed to grow as a soil saprophyte in arid deserts. To investigate hypotheses about the life history and evolution of Coccidioides, the genomes of several Onygenales, including C. immitis and C. posadasii; a close, nonpathogenic relative, Uncinocarpus reesii; and a more diverged pathogenic fungus, Histoplasma capsulatum, were sequenced and compared with those of 13 more distantly related Ascomycetes. This analysis identified increases and decreases in gene family size associated with a host/substrate shift from plants to animals in the Onygenales. In addition, comparison among Onygenales genomes revealed evolutionary changes in Coccidioides that may underlie its infectious phenotype, the identification of which may facilitate improved treatment and prevention of coccidioidomycosis. Overall, the results suggest that Coccidioides species are not soil saprophytes, but that they have evolved to remain associated with their dead animal hosts in soil, and that Coccidioides metabolism genes, membrane-related proteins, and putatively antigenic compounds have evolved in response to interaction with an animal host. PMID:19717792

  8. Molecular Detection of Pseudogymnoascus destructans (Ascomycota: Pseudeurotiaceae) and Unidentified Fungal Dermatitides on Big Brown Bats ( Eptesicus fuscus ) Overwintering inside Buildings in Canada.

    PubMed

    McAlpine, Donald F; McBurney, Scott; Sabine, Mary; Vanderwolf, Karen J; Park, Allysia; Y Cai, Hugh

    2016-10-01

    Big brown bats ( Eptesicus fuscus ) overwintering outside the underground environment are not believed to play a role in the epidemiology of the disease white-nose syndrome (WNS), caused by the fungus Pseudogymnoascus destructans (Pd). Using quantitative real-time PCR (qPCR), we provide molecular evidence for Pd on four big brown bats overwintering in heated buildings in New Brunswick, Canada. Two of the affected individuals also had very mild, focal, pustular, fungal dermatitis identified microscopically. A third bat, which was qPCR Pd-negative, had similar fungal lesions. Despite determining that these fungal lesions were caused by a suspected ascomycete, the intralesional fungi were not confirmed to be Pd. These findings demonstrate that bats overwintering in heated buildings and other above-ground sites may have subclinical or preclinical WNS, or be contaminated with Pd, and could play a role in local dispersal of Pd. Our inability to determine if the ascomycetes causing pustular lesions were Pd highlights the need for ancillary diagnostic tests, such as in situ hybridization or immunohistochemistry, so that Pd can be detected directly within a lesion. As the host-pathogen relationship for Pd evolves, and where bat species are exposed to the fungus under varying temperature regimes, lesions may become less stereotypic and such tests could help define these changes.

  9. Characterization of the reproductive mode and life cycle of the whitish truffle T. borchii.

    PubMed

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

    2016-08-01

    Truffles are the fruiting structures of ascomycetes in the genus Tuber. Because of their economic importance, truffles have been cultivated for many years using artificially inoculated host plants. Nevertheless, the life cycle and reproductive mode of Tuber spp. are still poorly understood. In filamentous ascomycetes, sexual reproduction is genetically controlled by the mating-type (MAT) locus. Among Tuber spp., the MAT locus has been recently characterized in the black truffles Tuber melanosporum and Tuber indicum. Here, by using sequence information derived from these species and from a Tuber borchii expressed sequence tag (EST) showing similarity to the mat1 gene of Alternaria brassicicola, we embarked on a chromosome-walking procedure to sequence the complete MAT region of T. borchii. This fungus produces highly commercialized whitish truffles and represents a model species for addressing basic questions concerning the life cycle of Tuber spp. We show that T. borchii is heterothallic, as its MAT locus is organized into two idiomorphs, each harbored by different mycelial strains. The alignment of the MAT locus from black truffles and T. borchii reveals that extensive sequence rearrangements and inversions occurred between these species. Moreover, by coupling mating-type analyses to karyological observation, we show that mycelia isolated from ascocarps and mycorrhizae are formed by homokaryotic hyphae.

  10. Identification of novel and robust internal control genes from Volvariella volvacea that are suitable for RT-qPCR in filamentous fungi

    PubMed Central

    Tao, Yongxin; van Peer, Arend Frans; Huang, Qianhui; Shao, Yanping; Zhang, Lei; Xie, Bin; Jiang, Yuji; Zhu, Jian; Xie, Baogui

    2016-01-01

    The selection of appropriate internal control genes (ICGs) is a crucial step in the normalization of real-time quantitative PCR (RT-qPCR) data. Housekeeping genes are habitually selected for this purpose, despite accumulating evidence on their instability. We screened for novel, robust ICGs in the mushroom forming fungus Volvariella volvacea. Nine commonly used and five newly selected ICGs were evaluated for expression stability using RT-qPCR data in eight different stages of the life cycle of V. volvacea. Three different algorithms consistently determined that three novel ICGs (SPRYp, Ras and Vps26) exhibited the highest expression stability in V. volvacea. Subsequent analysis of ICGs in twenty-four expression profiles from nine filamentous fungi revealed that Ras was the most stable ICG amongst the Basidiomycetous samples, followed by SPRYp, Vps26 and ACTB. Vps26 was expressed most stably within the analyzed data of Ascomycetes, followed by HH3 and β-TUB. No ICG was universally stable for all fungal species, or for all experimental conditions within a species. Ultimately, the choice of an ICG will depend on a specific set of experiments. This study provides novel, robust ICGs for Basidiomycetes and Ascomycetes. Together with the presented guiding principles, this enables the efficient selection of suitable ICGs for RT-qPCR. PMID:27405087

  11. 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.

  12. YeastIP: a database for identification and phylogeny of Saccharomycotina yeasts.

    PubMed

    Weiss, Stéphanie; Samson, Franck; Navarro, David; Casaregola, Serge

    2013-02-01

    With the advances in sequencing techniques, identification of ascomycetous yeasts to the species level and phylogeny reconstruction increasingly require curated and updated taxonomic information. A specific database with nucleotide sequences of the most common markers used for yeast taxonomy and phylogeny and a user-friendly interface allowing identification, taxonomy and phylogeny of yeasts species was developed. By 1 September 2012, the YeastIP database contained all the described Saccharomycotina species for which sequences used for taxonomy and phylogeny, such as D1/D2 rDNA and ITS, are available. The database interface was developed to provide a maximum of relevant information and data mining tools, including the following features: (1) the blast n program for the sequences of the YeastIP database; (2) easy retrieval of selected sequences; (3) display of the available markers for each selected group of species; and (4) a tool to concatenate marker sequences, including those provided by the user. The concatenation tool allows phylogeny reconstruction through a direct link to the Phylogeny.fr platform. YeastIP is thus a unique database in that it provides taxonomic information and guides users in their taxonomic analyses. YeastIP facilitates multigenic analysis to encourage good practice in ascomycetous yeast phylogeny (URL: http://genome.jouy.inra.fr/yeastip.).

  13. The effects of fungal root endophytes on plant growth: a meta-analysis.

    PubMed

    Mayerhofer, Michael S; Kernaghan, Gavin; Harper, Karen A

    2013-02-01

    Fungal root endophytes are plant associates that colonize root tissue internally without causing any obvious harm to their host. Although ubiquitous, this relationship is not well understood. Our objectives were to determine the effects of fungal root endophyte inoculation on plant biomass and nitrogen concentration by conducting an extensive meta-analysis. We also explored the effects of experimental conditions on the host-endophyte relationship. We performed analyses weighted with non-parametric variance on plant response to root endophytes from the Ascomycetes (excluding the Clavacipitaceae), including categorical analyses of 21 experimental factors, ranging from the identity of the host and the endophyte, to the composition of the growing medium. The response of total biomass to endophyte inoculation was 18% lower than non-inoculated controls, while individually, root biomass, shoot biomass, and nitrogen concentration responses to endophyte inoculation were neutral. The identities of both the host and the endophyte had an influence, as did the original source of the endophyte (whether or not the isolate used originated from the same host species). Experimental conditions also influenced the plant-endophyte relationship, with the most important being the availability and sources of carbon and organic nitrogen, particularly peat moss. Although our analysis demonstrates that overall plant biomass and nitrogen concentration responses to ascomycetous root endophyte inoculation is neutral to negative, these results are somewhat confounded by among-study differences in experimental conditions, which undoubtedly contribute to the high levels of variability in plant response seen in the literature.

  14. Unconventional Recombination in the Mating Type Locus of Heterothallic Apple Canker Pathogen Valsa mali

    PubMed Central

    Yin, Zhiyuan; Ke, Xiwang; Li, Zhengpeng; Chen, Jiliang; Gao, Xiaoning; Huang, Lili

    2017-01-01

    Sexual reproduction in filamentous ascomycetes is controlled by the mating type (MAT) locus, including two idiomorphs MAT1-1 and MAT1-2. Understanding the MAT locus can provide clues for unveiling the sexual development and virulence factors for fungal pathogens. The genus Valsa (Sordariomycetes, Diaporthales) contains many tree pathogens responsible for destructive canker diseases. The sexual stage of these ascomycetes is occasionally observed in nature, and no MAT locus has been reported to date. Here, we identified the MAT locus of the apple canker pathogen Valsa mali, which causes extensive damage, and even death, to trees. V. mali is heterothallic in that each isolate carries either the MAT1-1 or MAT1-2 idiomorph. However, the MAT structure is distinct from that of many other heterothallic fungi in the Sordariomycetes. Two flanking genes, COX13 and APN2, were coopted into the MAT locus, possibly by intrachromosomal rearrangement. After the acquisition of foreign genes, unequal recombination occurred between MAT1-1/2 idiomorphs, resulting in a reverse insertion in the MAT1-2 idiomorph. Evolutionary analysis showed that the three complete MAT1-1-2, COX13, and APN2 genes in this region diverged independently due to different selection pressure. Null hypothesis tests of a 1:1 MAT ratio of 86 V. mali isolates from four different provinces showed a relatively balanced distribution of the two idiomorphs in the fields. These results provide insights into the evolution of the mating systems in Sordariomycetes. PMID:28228472

  15. Yeasts colonizing the leaf surfaces.

    PubMed

    Sláviková, Elena; Vadkertiová, Renata; Vránová, Dana

    2007-08-01

    The yeasts were isolated from the leaf surfaces of ten species of trees. The study site was a forest park (Zelezná Studnicka) of the Small Carpathians mountain range. One hundred and thirty seven yeast strains belonging to 13 genera were isolated from 320 samples of leaves and needles. Seventeen yeast species were isolated, but only seven occurred regularly: Aureobasidium pullulans, Cryptococcus laurentii, Pichia anomala, Metschnikowia pulcherrima, Saccharomyces sp., Lachancea thermotolerans, and Rhodotorula glutinis. The remaining species were isolated from the leaves and needles of three or less tree species. A. pullulans, Cr. laurentii, and P. anomala were the most frequently found species and they occurred on leaves and needles of all ten tree species. Saccharomyces sp. occurred in leaf samples collected from eight kinds of trees. M. pulcherrima and L. thermotolerans were found in samples collected from six species of trees. Both these species occurred almost always on the leaves of deciduous trees. Rh. glutinis was the most frequently isolated carotenoids producing species. We have found out that the ascomycetous and basidiomycetous species were present in the leaf samples in approximately equal frequency, contrary to the soil samples taken from this forest park, where the ascomycetous species were found rarely.

  16. 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.

  17. 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.

  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.

  19. 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.

  20. Carbohydrate-active enzymes from the zygomycete fungus Rhizopus oryzae: a highly specialized approach to carbohydrate degradation depicted at genome level

    PubMed Central

    2011-01-01

    Background Rhizopus oryzae is a zygomycete filamentous fungus, well-known as a saprobe ubiquitous in soil and as a pathogenic/spoilage fungus, causing Rhizopus rot and mucomycoses. Results Carbohydrate Active enzyme (CAZy) annotation of the R. oryzae identified, in contrast to other filamentous fungi, a low number of glycoside hydrolases (GHs) and a high number of glycosyl transferases (GTs) and carbohydrate esterases (CEs). A detailed analysis of CAZy families, supported by growth data, demonstrates highly specialized plant and fungal cell wall degrading abilities distinct from ascomycetes and basidiomycetes. The specific genomic and growth features for degradation of easily digestible plant cell wall mono- and polysaccharides (starch, galactomannan, unbranched pectin, hexose sugars), chitin, chitosan, β-1,3-glucan and fungal cell wall fractions suggest specific adaptations of R. oryzae to its environment. Conclusions CAZy analyses of the genome of the zygomycete fungus R. oryzae and comparison to ascomycetes and basidiomycete species revealed how evolution has shaped its genetic content with respect to carbohydrate degradation, after divergence from the Ascomycota and Basidiomycota. PMID:21241472

  1. Amplification of soil fungal community DNA using the ITS86F and ITS4 primers.

    PubMed

    Vancov, Tony; Keen, Brad

    2009-07-01

    Internal transcribed spacer (ITS) 86F and ITS4 and the ITS1-F and ITS86R primer pairs were tested to specifically amplify fungal community DNA extracted from soil. Libraries were constructed from PCR-amplified fragments, sequenced and compared against sequences deposited in GenBank. The results confirmed that the ITS86F and ITS4 primer pair was selectively specific for the Ascomycetes, Basidiomycetes and Zygomycetes fungal clades. Amplified products generated by the ITS1F and ITS86R primer pair also aligned with sequences from a range of species within the Ascomycete and Basidiomycete clades but not from the Zygomycete. Both primer sets demonstrated fungal specificity and appear to be well suited for rapid PCR-based (fingerprinting) analysis of environmental fungal community DNA. This is the first reported use and assessment of the ITS86F and ITS4 and the ITS1-F and ITS86R primer pairs in amplifying fungal community DNA from soil.

  2. Pezizalean mycorrhizas and sporocarps in ponderosa pine (Pinus ponderosa) after prescribed fires in eastern Oregon, USA.

    PubMed

    Fujimura, K E; Smith, J E; Horton, T R; Weber, N S; Spatafora, J W

    2005-03-01

    Post-fire Pezizales fruit commonly in many forest types after fire. The objectives of this study were to determine which Pezizales appeared as sporocarps after a prescribed fire in the Blue Mountains of eastern Oregon, and whether species of Pezizales formed mycorrhizas on ponderosa pine, whether or not they were detected from sporocarps. Forty-two sporocarp collections in five genera (Anthracobia, Morchella, Peziza, Scutellinia, Tricharina) of post-fire Pezizales produced ten restriction fragment length polymorphism (RFLP) types. We found no root tips colonized by species of post-fire Pezizales fruiting at our site. However, 15% (6/39) of the RFLP types obtained from mycorrhizal roots within 32 soil cores were ascomycetes. Phylogenetic analyses of the 18S nuclear ribosomal DNA gene indicated that four of the six RFLP types clustered with two genera of the Pezizales, Wilcoxina and Geopora. Subsequent analyses indicated that two of these mycobionts were probably Wilcoxina rehmii, one Geopora cooperi, and one Geopora sp. The identities of two types were not successfully determined with PCR-based methods. Results contribute knowledge about the above- and below-ground ascomycete community in a ponderosa pine forest after a low intensity fire.

  3. Sexual variability in Histoplasma capsulatum and its possible distribution: what is going on?

    PubMed

    Muniz, Mauro Medeiros; Sousa, Carolina Nascimento; Evangelista Oliveira, Manoel Marques; Pizzini, Claudia Vera; Almeida, Marcos Abreu; Rodríguez-Arellanes, Gabriela; Taylor, Maria Lucia; Zancopé-Oliveira, Rosely Maria

    2014-01-01

    Histoplasma capsulatum is a dimorphic fungal pathogen naturally found in the soil. Inhalation of conidia can result in pulmonary histoplasmosis and, in some cases, causes severe disseminated disease and death. This fungus is an ascomycete that has an anamorphic or asexual stage and a teleomorphic or sexual stage, known as Ajellomyces capsulatus, which results from (+) and (-) mating types. Sexual reproduction is regulated by a specialized genomic region known as the mating-type (MAT1) locus. The mating process in this heterothallic species is represented by isolates that contain only one of the two different MAT1 locus idiomorphs (MAT1-1 or MAT1-2) that have unrelated sequences encoding different transcription factors. In medically important dimorphic pathogens and in most ascomycete molds, one MAT locus idiomorph encodes a high-mobility-group (HMG) box-domain transcription factor, and the other idiomorph encodes an alpha-box domain transcription factor. There is scarce molecular information about H. capsulatum mating type although recombinant population structures have been reported that could occur in nature and this process has been documented in distinct models such as parasites and other fungi. In this review, we shall focus on published studies on H. capsulatum sexuality, and outline the distribution of the two H. capsulatum mating types in Latin America. This manuscript is part of the series of works presented at the "V International Workshop: Molecular genetic approaches to the study of human pathogenic fungi" (Oaxaca, Mexico, 2012).

  4. 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

  5. The tempo and modes of evolution of reproductive isolation in fungi

    PubMed Central

    Giraud, T; Gourbière, S

    2012-01-01

    Reproductive isolation is an essential ingredient of speciation, and much has been learned in recent years about the evolution of reproductive isolation and the genetics of reproductive barriers in animals and plants. Fungi have been neglected on these aspects, despite being tractable model eukaryotes. Here, we used a model fitting approach to look at the importance of different barriers to gene flow to explain the decrease of reproductive compatibility with genetic distance in fungi. We found support for the occurrence of reinforcement in the presyngamy compatibility among basidiomycetes. In contrast, no evidence for reinforcement was detected in ascomycetes, concurring with the idea that host/habitat adaptation in this group can pleiotropically cause reproductive isolation. We found no evidence of a snowballing accumulation of postsyngamic reproductive incompatibilities in either ascomycetes or the complex of anther smut fungi. Together with previous studies, our results suggest that ecologically based barriers to gene flow and karyotypic differences may have an important role in hybrid inviability and sterility in fungi. Interestingly, hybrid sterility appeared to evolve faster than hybrid inviability in fungi. PMID:22669076

  6. Diverse ecological roles within fungal communities in decomposing logs of Picea abies.

    PubMed

    Ottosson, Elisabet; Kubartová, Ariana; Edman, Mattias; Jönsson, Mari; Lindhe, Anders; Stenlid, Jan; Dahlberg, Anders

    2015-03-01

    Fungal communities in Norway spruce (Picea abies) logs in two forests in Sweden were investigated by 454-sequence analyses and by examining the ecological roles of the detected taxa. We also investigated the relationship between fruit bodies and mycelia in wood and whether community assembly was affected by how the dead wood was formed. Fungal communities were highly variable in terms of phylogenetic composition and ecological roles: 1910 fungal operational taxonomic units (OTUs) were detected; 21% were identified to species level. In total, 58% of the OTUs were ascomycetes and 31% basidiomycetes. Of the 231 337 reads, 38% were ascomycetes and 60% basidiomycetes. Ecological roles were assigned to 35% of the OTUs, accounting for 62% of the reads. Wood-decaying fungi were the most common group; however, other saprotrophic, mycorrhizal, lichenized, parasitic and endophytic fungi were also common. Fungal communities in logs formed by stem breakage were different to those in logs originating from butt breakage or uprooting. DNA of specific species was detected in logs many years after the last recorded fungal fruiting. Combining taxonomic identification with knowledge of ecological roles may provide valuable insights into properties of fungal communities; however, precise ecological information about many fungal species is still lacking.

  7. Suppression subtractive hybridization and comparative expression analysis to identify developmentally regulated genes in filamentous fungi.

    PubMed

    Gesing, Stefan; Schindler, Daniel; Nowrousian, Minou

    2013-09-01

    Ascomycetes differentiate four major morphological types of fruiting bodies (apothecia, perithecia, pseudothecia and cleistothecia) that are derived from an ancestral fruiting body. Thus, fruiting body differentiation is most likely controlled by a set of common core genes. One way to identify such genes is to search for genes with evolutionary conserved expression patterns. Using suppression subtractive hybridization (SSH), we selected differentially expressed transcripts in Pyronema confluens (Pezizales) by comparing two cDNA libraries specific for sexual and for vegetative development, respectively. The expression patterns of selected genes from both libraries were verified by quantitative real time PCR. Expression of several corresponding homologous genes was found to be conserved in two members of the Sordariales (Sordaria macrospora and Neurospora crassa), a derived group of ascomycetes that is only distantly related to the Pezizales. Knockout studies with N. crassa orthologues of differentially regulated genes revealed a functional role during fruiting body development for the gene NCU05079, encoding a putative MFS peptide transporter. These data indicate conserved gene expression patterns and a functional role of the corresponding genes during fruiting body development; such genes are candidates of choice for further functional analysis.

  8. The Ustilago maydis Nit2 Homolog Regulates Nitrogen Utilization and Is Required for Efficient Induction of Filamentous Growth

    PubMed Central

    Horst, Robin J.; Zeh, Christine; Saur, Alexandra; Sonnewald, Sophia; Sonnewald, Uwe

    2012-01-01

    Nitrogen catabolite repression (NCR) is a regulatory strategy found in microorganisms that restricts the utilization of complex and unfavored nitrogen sources in the presence of favored nitrogen sources. In fungi, this concept has been best studied in yeasts and filamentous ascomycetes, where the GATA transcription factors Gln3p and Gat1p (in yeasts) and Nit2/AreA (in ascomycetes) constitute the main positive regulators of NCR. The reason why functional Nit2 homologs of some phytopathogenic fungi are required for full virulence in their hosts has remained elusive. We have identified the Nit2 homolog in the basidiomycetous phytopathogen Ustilago maydis and show that it is a major, but not the exclusive, positive regulator of nitrogen utilization. By transcriptome analysis of sporidia grown on artificial media devoid of favored nitrogen sources, we show that only a subset of nitrogen-responsive genes are regulated by Nit2, including the Gal4-like transcription factor Ton1 (a target of Nit2). Ustilagic acid biosynthesis is not under the control of Nit2, while nitrogen starvation-induced filamentous growth is largely dependent on functional Nit2. nit2 deletion mutants show the delayed initiation of filamentous growth on maize leaves and exhibit strongly compromised virulence, demonstrating that Nit2 is required to efficiently initiate the pathogenicity program of U. maydis. PMID:22247264

  9. 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

  10. A WDR Gene Is a Conserved Member of a Chitin Synthase Gene Cluster and Influences the Cell Wall in Aspergillus nidulans

    PubMed Central

    Guerriero, Gea; Silvestrini, Lucia; Obersriebnig, Michael; Hausman, Jean-Francois; Strauss, Joseph; Ezcurra, Inés

    2016-01-01

    WD40 repeat (WDR) proteins are pleiotropic molecular hubs. We identify a WDR gene that is a conserved genomic neighbor of a chitin synthase gene in Ascomycetes. The WDR gene is unique to fungi and plants, and was called Fungal Plant WD (FPWD). FPWD is within a cell wall metabolism gene cluster in the Ascomycetes (Pezizomycotina) comprising chsD, a Chs activator and a GH17 glucanase. The FPWD, AN1556.2 locus was deleted in Aspergillus nidulans strain SAA.111 by gene replacement and only heterokaryon transformants were obtained. The re-annotation of Aspergilli genomes shows that AN1556.2 consists of two tightly linked separate genes, i.e., the WDR gene and a putative beta-flanking gene of unknown function. The WDR and the beta-flanking genes are conserved genomic neighbors localized within a recently identified metabolic cell wall gene cluster in genomes of Aspergilli. The heterokaryons displayed increased susceptibility to drugs affecting the cell wall, and their phenotypes, observed by optical, confocal, scanning electron and atomic force microscopy, suggest cell wall alterations. Quantitative real-time PCR shows altered expression of some cell wall-related genes. The possible implications on cell wall biosynthesis are discussed. PMID:27367684

  11. Molecular evolution and functional divergence of tubulin superfamily in the fungal tree of life

    PubMed Central

    Zhao, Zhongtao; Liu, Huiquan; Luo, Yongping; Zhou, Shanyue; An, Lin; Wang, Chenfang; Jin, Qiaojun; Zhou, Mingguo; Xu, Jin-Rong

    2014-01-01

    Microtubules are essential for various cellular activities and β-tubulins are the target of benzimidazole fungicides. However, the evolution and molecular mechanisms driving functional diversification in fungal tubulins are not clear. In this study, we systematically identified tubulin genes from 59 representative fungi across the fungal kingdom. Phylogenetic analysis showed that α-/β-tubulin genes underwent multiple independent duplications and losses in different fungal lineages and formed distinct paralogous/orthologous clades. The last common ancestor of basidiomycetes and ascomycetes likely possessed two paralogs of α-tubulin (α1/α2) and β-tubulin (β1/β2) genes but α2-tubulin genes were lost in basidiomycetes and β2-tubulin genes were lost in most ascomycetes. Molecular evolutionary analysis indicated that α1, α2, and β2-tubulins have been under strong divergent selection and adaptive positive selection. Many positively selected sites are at or adjacent to important functional sites and likely contribute to functional diversification. We further experimentally confirmed functional divergence of two β-tubulins in Fusarium and identified type II variations in FgTub2 responsible for function shifts. In this study, we also identified δ-/ε-/η-tubulins in Chytridiomycetes. Overall, our results illustrated that different evolutionary mechanisms drive functional diversification of α-/β-tubulin genes in different fungal lineages, and residues under positive selection could provide targets for further experimental study. PMID:25339375

  12. Starmerella syriaca f.a., sp. nov., an osmotolerant yeast species isolated from flowers in Syria.

    PubMed

    Sipiczki, Matthias

    2015-04-01

    Four strains of a novel asexual ascomycetous yeast species were isolated from Malva sp. flowers in Syria. Sequencing of the regions spanning the small subunit, 5.8S, and the D1/D2 domains of the large subunit ribosomal RNA genes showed that the isolates were conspecific. Comparative analysis of these sequences and the corresponding sequences of the type strains of ascomycetous yeasts revealed that the novel species is phylogenetically related to members of the Starmerella clade. Its closest relative is Candida vaccinii. For the new species the name Starmerella syriaca is proposed. Its strains are osmotolerant and produce pseudohypha-like structures capable of penetrating agar media. The type strain is 2-1362(T) (=CBS 13909(T) = NCAIM Y.02138(T) = CCY 090-003-001(T)). The GenBank accession numbers for its nucleotide sequences are: JX515986 (D1/D2 LSU), JX515987 (ITS1-5.8S-ITS2) and JX515988 (SSU). Mycobank: MB 810090.

  13. Community composition of root-associated fungi in a Quercus-dominated temperate forest: "codominance" of mycorrhizal and root-endophytic fungi.

    PubMed

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

    2013-05-01

    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.

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

    PubMed

    Kurtzman, Cletus P; Robnett, Christie J

    2013-02-01

    Relationships among ascomycetous yeast genera (subphylum Saccharomycotina, phylum Ascomycota) have 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 subunit (SSU) rRNA, translation elongation factor-1α, and RNA polymerase II, subunits 1 (RPB1) and 2 (RPB2). The analysis substantiates earlier proposals that all known ascomycetous yeast genera now assigned to the Saccharomycotina represent a single clade. Maximum likelihood analysis resolved the taxa into eight large multigenus clades and four-one- and two-genus clades. Maximum parsimony and neighbor-joining analyses gave similar results. Genera of the family Saccharomycetaceae remain as one large clade as previously demonstrated, to which the genus Cyniclomyces is now assigned. Pichia, Saturnispora, Kregervanrija, Dekkera, Ogataea and Ambrosiozyma are members of a single large clade, which is separate from the clade that includes Barnettozyma, Cyberlindnera, Phaffomyces, Starmera and Wickerhamomyces. Other clades include Kodamaea, Metschnikowia, Debaryomyces, Cephaloascus and related genera, which are separate from the clade that includes Zygoascus, Trichomonascus, Yarrowia and others. This study once again demonstrates that there is limited congruence between a system of classification based on phenotype and a system determined from DNA sequences.

  15. Yeast communities in Sphagnum phyllosphere along the temperature-moisture ecocline in the boreal forest-swamp ecosystem and description of Candida sphagnicola sp. nov.

    PubMed

    Kachalkin, Aleksey V; Yurkov, Andrey M

    2012-06-01

    The effects of the temperature-moisture factors on the phylloplane yeast communities inhabiting Sphagnum mosses were studied along the transition from a boreal forest to a swamp biotope at the Central Forest State Biosphere Reserve (Tver region, Russia). We tested the hypothesis that microclimatic parameters affect yeast community composition and structure even on a rather small spatial scale. Using a conventional plating technique we isolated and identified by molecular methods a total of 15 species of yeasts. Total yeast counts and species richness values did not depend on environmental factors, although yeast community composition and structure did. On average, Sphagnum in the swamp biotope supported a more evenly structured yeast community. Relative abundance of ascomycetous yeasts was significantly higher on swamp moss. Rhodotorula mucilaginosa dominated in the spruce forest and Cryptococcus magnus was more abundant in the swamp. Our study confirmed the low occurrence of tremellaceous yeasts in the Sphagnum phyllosphere. Of the few isolated ascomycetous yeast and yeast-like species, some were differentiated from hitherto known species in physiological tests and phylogenetic analyses. We describe one of them as Candida sphagnicola and designate KBP Y-3887(T) (=CBS 11774(T) = VKPM Y-3566(T) = MUCL 53590(T)) as the type strain. The new species was registered in MycoBank under MB 563443.

  16. 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

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

    PubMed Central

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

    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 β-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. Overwintering of Vineyard Yeasts: Survival of Interacting Yeast Communities in Grapes Mummified on Vines

    PubMed Central

    Sipiczki, Matthias

    2016-01-01

    The conversion of grape must into wine involves the development and succession of yeast populations differing in species composition. The initial population is formed by vineyard strains which are washed into the must from the crushed grapes and then completed with yeasts coming from the cellar environment. As the origin and natural habitat of the vineyard yeasts are not fully understood, this study addresses the possibility, that grape yeasts can be preserved in berries left behind on vines at harvest until the spring of the next year. These berries become mummified during the winter on the vines. To investigate whether yeasts can survive in these overwintering grapes, mummified berries were collected in 16 localities in the Tokaj wine region (Hungary-Slovakia) in early March. The collected berries were rehydrated to recover viable yeasts by plating samples onto agar plates. For the detection of minority species which would not be detected by direct plating, an enrichment step repressing the propagation of alcohol-sensitive yeasts was also included in the process. The morphological, physiological, and molecular analysis identified 13 basidiomycetous and 23 ascomycetous species including fermentative yeasts of wine-making relevance among the 3879 isolates. The presence of viable strains of these species demonstrates that the grapes mummified on the vine can serve as a safe reservoir of yeasts, and may contribute to the maintenance of grape-colonizing yeast populations in the vineyard over years, parallel with other vectors and habitats. All basidiomycetous species were known phylloplane yeasts. Three Hanseniaspora species and pigmented Metschnikowia strains were the most frequent ascomycetes. Other fermentative yeasts of wine-making relevance were detected only in the enrichment cultures. Saccharomyces (S. paradoxus, S. cerevisiae, and S. uvarum) were recovered from 13% of the samples. No Candida zemplinina was found. The isolates with Aureobasidium morphology

  19. 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

  20. Nematocera (Ceratopogonidae, Psychodidae, Simuliidae and Culicidae) and control methods.

    PubMed

    Braverman, Y

    1994-12-01

    The biology, veterinary importance and control of certain Nematocera are described and discussed. Culicoides spp. (family Ceratopogonidae) transmit the arboviruses of bluetongue (BT), African horse sickness (AHS), bovine ephemeral fever (BEF) and Akabane. Some other arboviruses have been isolated from these species, while fowl pox has been transmitted experimentally by Culicoides. These insects are vectors of the parasitic protozoans Leucocytozoon caulleryi and Haemoproteus nettionis, and the parasitic nematodes Onchocerca gutturosa, O. gibsoni and O. cervicalis. They also cause recurrent summer hypersensitivity in horses, ponies, donkeys, cattle and sheep. Farm animals can die as a result of mass attack by Simulium spp., which are also vectors of Leucocytozoon simondi, L. smithi and the filariae O. gutturosa, O. linealis and O. ochengi. Venezuelan equine encephalomyelitis (VEE) and Rift Valley fever (RVF) have been isolated from simuliids, and vesicular stomatitis virus New Jersey strain has been replicated in Simulium vittatum. Simuliids are well known as vectors of O. volvulus, the cause of human onchocercosis (river blindness). The family Psychodidae includes the genera Phlebotomus and Lutzomyia (subfamily Phlebotominae), vectors of Leishmania spp. in humans, dogs and other mammals. Vesicular stomatitis virus Indiana strain has been regularly isolated from phlebotomine sandflies. Mass attack by mosquitoes can also prove fatal to farm animals. Mosquitoes are vectors of the viruses of Akabane, BEF, RVF, Japanese encephalitis, VEE, western equine encephalomyelitis, eastern equine encephalomyelitis and west Nile meningoencephalitis, secondary vectors of AHS and suspected vectors of Israel turkey meningoencephalitis. The viruses of hog cholera, fowl pox and reticuloendotheliosis, the rickettsiae Eperythrozoon ovis and E. suis, and the bacterium Borrelia anserina are mechanically transmitted by mosquitoes. These insects also induce allergic dermatitis in horses. They

  1. 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

  2. How Past and Present Influence the Foraging of Clonal Plants?

    PubMed Central

    Louâpre, Philipe; Bittebière, 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

  3. Candida sergipensis, a new asexual yeast species isolated from frozen pulps of tropical fruits.

    PubMed

    Trindade, Rita C; Resende, Maria A; Pimenta, Raphael S; Lachance, Marc-André; Rosa, Carlos A

    2004-07-01

    Sixteen strains of the new yeast species Candida sergipensis have been isolated from frozen pulps of the tropical fruits umbú ( Spondias tuberosa Avr. Cam.) and mangaba ( Hancornia speciosa Gom.). Candida sergipensis was one of the prevalent species in the yeast community of these substrates. The new asexual ascomycetous yeast is phylogenetically related to Candida spandovensis and Candida sorbophila, species belonging to the Wickerhamiella clade, as evidenced by the sequences of the D1/D2 domains of their large subunit ribosomal DNAs. The species C. sergipensis and C. spandovensis can be separated on the basis of growth on 50% glucose agar, xylose and succinate, negative for the first species and positive for the second. The type culture is strain UFMG-R188 (CBS 9567).

  4. Characterisation of α-chitin extracted from a lichenised fungus species Xanthoria parietina.

    PubMed

    Kaya, Murat; Halıcı, Mehmet Gökhan; Duman, Fatih; Erdoğan, Sevil; Baran, Talat

    2015-01-01

    Lichens are symbiotic associations formed mainly by ascomycete fungi and green algae or cyanobacteria. The presence of chitin in the fungal cell wall has been revealed by previous studies. Considering the presence of fungi in the lichens, this work determines the presence of chitin in a cosmopolitan lichen species Xanthoria parietina. In this study, chitin was derived from a lichen species for the first time and its physicochemical properties were determined by Fourier transform infrared spectroscopy, thermogravimetric analysis, X-ray diffraction, scanning electron microscopy and elemental analysis. The dry weight chitin content of X. parietina was 4.23%, and this chitin was in the α-form. The crystalline index value of the lichen chitin was calculated as 70.1%. The chitin from X. parietina had a smooth surface.

  5. Perithecium morphogenesis in Sordaria macrospora.

    PubMed

    Lord, Kathryn M; Read, Nick D

    2011-04-01

    The perithecium of the self-fertile ascomycete Sordaria macrospora provides an excellent model in which to analyse fungal multicellular development. This study provides a detailed analysis of perithecium morphogenesis in the wild type and eight developmental mutants of S. macrospora, using a range of correlative microscopical techniques. Fundamentally, perithecia and other complex multicellular structures produced by fungi arise by hyphal aggregation and adhesion, and these processes are followed by specialization and septation of hyphal compartments within the aggregates. Perithecial morphogenesis can be divided into the ascogonial, protoperithecial, and perithecial stages of development. At least 13 specialized, morphologically distinct cell-types are involved in perithecium morphogenesis, and these fall into three basic classes: hyphae, conglutinate cells and spores. Conglutinate cells arise from hyphal adhesion and certain perithecial hyphae develop from conglutinate cells. Various hypha-conglutinate cell transitions play important roles during the development of the perithecial wall and neck.

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

    PubMed

    Kurtzman, Cletus P; Robnett, Christie J

    2014-05-01

    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 factor-1α and RNA polymerase II, subunits B1 and B2. The new taxa are: Deakozyma gen. nov., type species Deakozyma indianensis sp. nov. (type strain NRRL YB-1937, CBS 12903); Danielozyma gen. nov., type species Danielozyma ontarioensis comb. nov. (type strain NRRL YB-1246, CBS 8502); D. litseae comb. nov. (type strain NRRL YB-3246, CBS 8799); Middelhovenomyces gen. nov., type species Middelhovenomyces tepae comb. nov. (type strain NRRL Y-17670, CBS 5115) and M. petrohuensis comb. nov. (type strain NRRL Y-17663, CBS 8173).

  7. 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.

  8. Variation of Soil Mycoflora in Decomposition of Rice Stubble from Rice-wheat Cropping System

    PubMed Central

    Sinha, Asha

    2007-01-01

    The colonization pattern and extent of decay produced in paddy stubble by soil inhabiting mycoflora were done by using nylon net bag technique. Among the three methods used for isolation of fungi, dilution plate technique recorded the highest number of fungi followed by damp chamber and direct observation method. Nutrient availability and climatic conditions (temperature, humidity and rainfall) influenced the occurrence and colonization pattern of fungi. Maximum fungal population was recorded in October (48.99 × 104/g dry litter) and minimum in May (11.41 × 104/g dry litter). Distribution of Deuteromycetous fungi was more in comparison to Zygomycetes, oomycetes and ascomycetes. In the early stage of decomposition Mucor racemosus, Rhizopus nigricans, Chaetomium globosum and Gliocladium species were found primarly whereas at later stages of decomposition preponderance of Aspergillus candidus, Torula graminis, Cladosporiun cladosporioides and Aspergillus luchuensis was recorded. PMID:24015096

  9. Integration of the first and second generation bioethanol processes and the importance of by-products.

    PubMed

    Lennartsson, Patrik R; Erlandsson, Per; Taherzadeh, Mohammad J

    2014-08-01

    Lignocellulosic ethanol has obstacles in the investment costs and uncertainties in the process. One solution is to integrate it with the running dry mills of ethanol from grains. However, the economy of these mills, which dominate the world market, are dependent on their by-products DDGS (Distiller's Dried Grains and Solubles), sold as animal feed. The quality of DDGS therefore must not be negatively influenced by the integration. This puts restraints on the choice of pretreatment of lignocelluloses and utilizing the pentose sugars by food-grade microorganisms. The proposed solution is to use food related filamentous Zygomycetes and Ascomycetes fungi, and to produce fungal biomass as a high-grade animal feed from the residues after the distillation (stillage). This also has the potential to improve the first generation process by increasing the amount of the thin stillage directly sent back into the process, and by decreasing the evaporator based problems.

  10. 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

  11. 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.

  12. Soil mycoflora from the Dead Sea Oases of Ein Gedi and Einot Zuqim (Israel).

    PubMed

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

    1997-10-01

    Samples were taken from the top 10 cm of soils from 24 points in the Ein Gedi area. Among 329 isolates, 142 species were identified: 11 genera of ascomycetes, one genus of coelomycetes, 28 genera of hyphomycetes, 7 genera of zygomycetes and one yeast, in addition to some unidentified basidiomycetes. The hyphomycetes were represented by 17 dematiaceous, 9 mucedinaceous and two tuberculariaceous. Melanconiaceous and stilbellaceous genera were not found. Two new varieties of Microascus recently described were reisolated. No strict thermophiles or halophiles were obtained. There is apparently no very characteristic or specific fungal flora of the Dead Sea Oases although it was different from that found in the desert soil surrounding this area.

  13. Phylogeny of Metschnikowia species estimated from partial rRNA sequences.

    PubMed

    Mendonça-Hagler, L C; Hagler, A N; Kurtzman, C P

    1993-04-01

    Phylogenetic relationships of species assigned to the genus Metschnikowia were estimated from the extents of divergence among partial sequences of rRNA. The data suggest that the aquatic species (Metschnikowia australis, Metschnikowia bicuspidata, Metschnikowia krissii, and Metschnikowia zobellii) and the terrestrial species (Metschnikowia hawaiiensis, Metschnikowia lunata, Metschnikowia pulcherrima, and Metschnikowia reukaufii) form two groups within the genus. M. lunata and M. hawaiiensis are well separated from other members of the genus, and M. hawaiiensis may be sufficiently divergent that it could be placed in a new genus. Species of the genus Metschnikowia are unique compared with other ascomycetous yeasts because they have a deletion in the large-subunit rRNA sequence that includes nucleotides 434 to 483.

  14. Myco-fluidics: The fluid dynamics of fungal chimerism

    NASA Astrophysics Data System (ADS)

    Roper, Marcus; Hickey, Patrick; Dressaire, Emilie; Roch, Sebastien

    2012-11-01

    Chimeras-fantastical creatures formed as amalgams of many animals-have captured the human imagination since Ancient times. But they are also surprisingly common in Nature. The syncytial cells of filamentous fungi harbor large numbers of nuclei bathed in a single cytoplasm. As a fungus grows these nuclei become genetically diverse, either from mutation or from exchange of nuclei between different fungal individuals, a process that is known to increase the virulence of the fungus and its adaptability. By directly measuring nuclear movement in the model ascomycete fungus Neurospora crassa, we show that the fungus' tolerance for internal genetic diversity is enabled by hydrodynamic mixing of nuclei acting at all length scales within the fungal mycelium. Mathematical modeling and experiments in a mutant with altered mycelial morphology reveal some of the exquisite hydraulic engineering necessary to create these mixing flows from spatially coarse pressure gradients.

  15. The effect of acetylated xylan and sugar beet pulp on the expression and secretion of enzymes by Penicillium purpurogenum.

    PubMed

    Navarrete, Mario; Callegari, Eduardo; Eyzaguirre, Jaime

    2012-01-01

    Sugar beet pulp is a natural carbon source composed mainly of pectin and cellulose, which is utilized and degraded by the ascomycete Penicillium purpurogenum. The fungus also grows on and degrades acetylated xylan which lacks cellulose and pectin. Both carbon sources have been used in our laboratory to grow the fungus and to purify different enzymes secreted to the medium. The enzymes involved in the complex process of degradation of these carbon sources by the fungus have been explored previously under non-denaturing conditions; multienzyme complexes were separated and some subunits identified by Western blots and mass spectrometry. In this work, proteomic profiles show that the secretome is composed of numerous proteins varying in pI and molecular weight. Some enzymes are common to both growth conditions, while others are specific for each carbon source. The results show that the carbon sources utilized exert strong regulatory control over the proteins secreted. This is the first secretome study from a lignocellulolytic Penicillium.

  16. Fungicides degradation in an organic biomixture: impact on microbial diversity.

    PubMed

    Coppola, Laura; Comitini, Francesca; Casucci, Cristiano; Milanovic, Vesna; Monaci, Elga; Marinozzi, Maria; Taccari, Manuela; Ciani, Maurizio; Vischetti, Costantino

    2011-12-15

    Biological systems are being developed all over EU countries to protect water-bodies from pesticide contamination at farm level. A laboratory experiment was carried out to test the efficiency of a mixture of compost and straw in bio-degrading different mixtures of fungicides usually applied in vineyards. At the same time the effects of fungicide applications on microbial community of biomixture were also evaluated. Results showed that the biomixture had a good capability of degrading pesticides. Indeed, at the end of the experiment (112 days), the concentration of most of the pesticides was close to complete degradation. Denaturing gradient gel electrophoresis (DGGE) analysis showed an evident modification of microbial diversity after the addition of fungicides. However, at the end of degradation process, no significant changes in the composition of microbial community were seen. In this specific substrate used in the biomixture, yeast flora and ascomycete filamentous fungi seemed to be involved in the degradation activity.

  17. Description of Groenewaldozyma gen. nov. for placement of Candida auringiensis, Candida salmanticensis and Candida tartarivorans.

    PubMed

    Kurtzman, Cletus P

    2016-07-01

    DNA sequence analyses have demonstrated that species of the polyphyletic anamorphic ascomycete genus Candida may be members of described teleomorphic genera, members of the Candida tropicalis clade upon which the genus Candida is circumscribed, or members of isolated clades that represent undescribed genera. From phylogenetic analysis of gene sequences from nuclear large subunit rRNA, mitochondrial small subunit rRNA and cytochrome oxidase II, Candida auringiensis (NRRL Y-17674(T), CBS 6913(T)), Candida salmanticensis (NRRL Y-17090(T), CBS 5121(T)), and Candida tartarivorans (NRRL Y-27291(T), CBS 7955(T)) were shown to be members of an isolated clade and are proposed for reclassification in the genus Groenewaldozyma gen. nov. (MycoBank MB 815817). Neighbouring taxa include species of the Wickerhamiella clade and Candida blankii.

  18. 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

  19. The importance of molecular analyses for understanding the genetic diversity of Histoplasma capsulatum: an overview.

    PubMed

    Vite-Garín, Tania; Estrada-Bárcenas, Daniel Alfonso; Cifuentes, Joaquín; Taylor, Maria Lucia

    2014-01-01

    Advances in the classification of the human pathogen Histoplasma capsulatum (H. capsulatum) (ascomycete) are sustained by the results of several genetic analyses that support the high diversity of this dimorphic fungus. The present mini-review highlights the great genetic plasticity of H. capsulatum. Important records with different molecular tools, mainly single- or multi-locus sequence analyses developed with this fungus, are discussed. Recent phylogenetic data with a multi-locus sequence analysis using 5 polymorphic loci support a new clade and/or phylogenetic species of H. capsulatum for the Americas, which was associated with fungal isolates obtained from the migratory bat Tadarida brasiliensis. This manuscript is part of the series of works presented at the "V International Workshop: Molecular genetic approaches to the study of human pathogenic fungi" (Oaxaca, Mexico, 2012).

  20. Endophytic fungi diversity of aquatic/riparian plants and their antifungal activity in vitro.

    PubMed

    Li, Hai-Yan; Zhao, Chun-An; Liu, Chen-Jian; Xu, Xiao-Fei

    2010-02-01

    Two hundred and fourteen endophytic fungi were isolated from 500 segments of aquatic/riparian plants Ottelia acuminata, Myriophyllum verticillatum, Equisetum arvense, Cardamine multijuga, and Impatiens chinensis. They were identified to 31 taxa in which Cladosporium, Fusarium, and Geotrichum were the dominant genera. Among all isolates, 169 (79%) were anamorphic fungi, 1 (0.5%) was an teleomorphic ascomycete and 44 (21%) were sterile mycelia. There were significant differences in the colonization frequency of endophytes between the five plant species (X~2=51.128, P<0.001, Chi-square test). The riparian plants harboured more endophytes than the submerged plants. The antifungal activity of these isolates against Fusarium solani and Phytophthora nicotianae in vitro were tested and 28 (13.1%) isolates showed antifungal activities with more than 30% growth inhibition rate against the two pathogens.

  1. Candida bromeliacearum sp. nov. and Candida ubatubensis sp. nov., two yeast species isolated from the water tanks of Canistropsis seidelii (Bromeliaceae).

    PubMed

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

    2005-09-01

    Strains belonging to two novel yeast species, Candida bromeliacearum and Candida ubatubensis, were isolated from the bromeliad tank of Canistropsis seidelii (Bromeliaceae) in a sandy coastal plain (restinga) ecosystem site in an Atlantic rainforest of south-eastern Brazil. These species were genetically distinct from all other currently accepted ascomycetous yeasts, based on sequence divergence in the D1/D2 domains of the large-subunit rDNA and in the small-subunit rDNA. The species occupy basal positions in the Metschnikowiaceae clade. The type strains are Candida bromeliacearum UNESP 00-103(T) (=CBS 10002(T)=NRRL Y-27811(T)) and Candida ubatubensis UNESP 01-247R(T) (=CBS 10003(T)=NRRL Y-27812(T)).

  2. The chestnut blight fungus for studies on virus/host and virus/virus interactions: from a natural to a model host.

    PubMed

    Eusebio-Cope, Ana; Sun, Liying; Tanaka, Toru; Chiba, Sotaro; Kasahara, Shin; Suzuki, Nobuhiro

    2015-03-01

    The chestnut blight fungus, Cryphonectria parasitica, is an important plant pathogenic ascomycete. The fungus hosts a wide range of viruses and now has been established as a model filamentous fungus for studying virus/host and virus/virus interactions. This is based on the development of methods for artificial virus introduction and elimination, host genome manipulability, available host genome sequence with annotations, host mutant strains, and molecular tools. Molecular tools include sub-cellular distribution markers, gene expression reporters, and vectors with regulatable promoters that have been long available for unicellular organisms, cultured cells, individuals of animals and plants, and certain filamentous fungi. A comparison with other filamentous fungi such as Neurospora crassa has been made to establish clear advantages and disadvantages of C. parasitica as a virus host. In addition, a few recent studies on RNA silencing vs. viruses in this fungus are introduced.

  3. Phenylphenalenones protect banana plants from infection by Mycosphaerella fijiensis and are deactivated by metabolic conversion.

    PubMed

    Hidalgo, William; Chandran, Jima N; Menezes, Riya C; Otálvaro, Felipe; Schneider, Bernd

    2016-03-01

    Phenylphenalenones, polycyclic aromatic natural products from some monocotyledonous plants, are known as phytoalexins in banana (Musa spp.). In this study, (1) H nuclear magnetic resonance (NMR)-based metabolomics along with liquid chromatography and mass spectrometry were used to explore the chemical responses of the susceptible 'Williams' and the resistant 'Khai Thong Ruang' Musa varieties to the ascomycete fungus Mycosphaerella fijiensis, the agent of the black leaf Sigatoka disease. Principal component analysis discriminated strongly between infected and non-infected plant tissue, mainly because of specialized metabolism induced in response to the fungus. Phenylphenalenones are among the major induced compounds, and the resistance level of the plants was correlated with the progress of the disease. However, a virulent strain of M. fijiensis was able to overcome plant resistance by converting phenylphenalenones to sulfate conjugates. Here, we report the first metabolic detoxification of fungitoxic phenylphenalenones to evade the chemical defence of Musa plants.

  4. How nutritional status signalling coordinates metabolism and lignocellulolytic enzyme secretion.

    PubMed

    Brown, Neil Andrew; Ries, Laure Nicolas Annick; Goldman, Gustavo Henrique

    2014-11-01

    The utilisation of lignocellulosic plant biomass as an abundant, renewable feedstock for green chemistries and biofuel production is inhibited by its recalcitrant nature. In the environment, lignocellulolytic fungi are naturally capable of breaking down plant biomass into utilisable saccharides. Nonetheless, within the industrial context, inefficiencies in the production of lignocellulolytic enzymes impede the implementation of green technologies. One of the primary causes of such inefficiencies is the tight transcriptional control of lignocellulolytic enzymes via carbon catabolite repression. Fungi coordinate metabolism, protein biosynthesis and secretion with cellular energetic status through the detection of intra- and extra-cellular nutritional signals. An enhanced understanding of the signals and signalling pathways involved in regulating the transcription, translation and secretion of lignocellulolytic enzymes is therefore of great biotechnological interest. This comparative review describes how nutrient sensing pathways regulate carbon catabolite repression, metabolism and the utilisation of alternative carbon sources in Saccharomyces cerevisiae and ascomycete fungi.

  5. The Post-genomic Era of Trichoderma reesei: What's Next?

    PubMed

    Gupta, Vijai Kumar; Steindorff, Andrei Stecca; de Paula, Renato Graciano; Silva-Rocha, Rafael; Mach-Aigner, Astrid R; Mach, Robert L; Silva, Roberto N

    2016-12-01

    The ascomycete Trichoderma reesei is one of the most well studied cellulolytic microorganisms. This fungus is widely used in the biotechnology industry, mainly in the production of biofuels. Due to its importance, its genome was sequenced in 2008, opening new avenues to study this microorganism. In this 'post-genomic' era, a transcriptomic and proteomic era has emerged. Here, we present an overview of new findings in the gene expression regulation network of T. reesei. We also discuss new rational strategies to obtain mutants that produce hydrolytic enzymes with a higher yield, using metabolic engineering. Finally, we present how synthetic biology strategies can be used to create engineered promoters to efficiently synthesize enzymes for biomass degradation to produce bioethanol.

  6. Mycotic dermatitis in an Atlantic white-sided dolphin, a pygmy sperm whale, and two harbor seals.

    PubMed

    Frasca, S; Dunn, J L; Cooke, J C; Buck, J D

    1996-03-01

    An Atlantic white-sided dolphin (Lagenorhynchus acutus), a pygmy sperm whale (Kogia breviceps), 2 harbor seals (Phoca vitulina) developed raised, firm, erythematous, cutaneous nodules that were most prominent on their heads, trunks, and on the caudal portions of their bodies. Prior to the onset of the condition, all 4 animals may have been stressed by factors such as being stranded on a beach, being transported long distances, or being relocated locally. Microbial culturing of the lesions on multiple media yielded fungal isolates containing conidia characteristic of Fusarium spp. Hyphae consistent with those of an ascomycete were evident on histologic examination of lesions. In each treated animal, the dermatitis resolved 3 to 4 weeks after completing treatment with ketoconazole. Fusarium spp may be opportunistic invaders of the skin of marine mammals that have decreased immunocompetence or integumentary compromise.

  7. Cellulases and beyond: the first 70 years of the enzyme producer Trichoderma reesei.

    PubMed

    Bischof, Robert H; Ramoni, Jonas; Seiboth, Bernhard

    2016-06-10

    More than 70 years ago, the filamentous ascomycete Trichoderma reesei was isolated on the Solomon Islands due to its ability to degrade and thrive on cellulose containing fabrics. This trait that relies on its secreted cellulases is nowadays exploited by several industries. Most prominently in biorefineries which use T. reesei enzymes to saccharify lignocellulose from renewable plant biomass in order to produce biobased fuels and chemicals. In this review we summarize important milestones of the development of T. reesei as the leading production host for biorefinery enzymes, and discuss emerging trends in strain engineering. Trichoderma reesei has very recently also been proposed as a consolidated bioprocessing organism capable of direct conversion of biopolymeric substrates to desired products. We therefore cover this topic by reviewing novel approaches in metabolic engineering of T. reesei.

  8. 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.

  9. 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.

  10. 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 Guimarães; 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.

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

    PubMed

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

    2013-09-01

    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.

  12. 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.

  13. 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.

  14. [Diversity of facultatively anaerobic microscopic mycelial fungi in soils].

    PubMed

    Kurakov, A V; Lavrent'ev, R B; Nechitaĭlo, T Iu; Golyshin, P N; Zviagintsev, D G

    2008-01-01

    The numbers of microscopic fungi isolated from soil samples after anaerobic incubation varied from tens to several hundreds of CFU per one gram of soil; a total of 30 species was found. This group is composed primarily of mitotic fungi of the ascomycete affinity belonging to the orders Hypocreales (Fusarium solani, F. oxysporum, Fusarium sp., Clonostachys grammicospora, C. rosea. Acremonium sp., Gliocladium penicilloides, Trichoderma aureoviride, T. harzianum, T. polysporum, T. viride. T. koningii, Lecanicillum lecanii, and Tolypocladium inflatum) and Eurotiales (Aspergillus terreus, A. niger, and Paecilomyces lilacimus), as well as to the phylum Zygomycota, to the order Mucorales (Actinomucor elegans, Absidia glauca, Mucor circinelloides, M. hiemalis, M. racemosus, Mucor sp., Rhizopus oryzae, Zygorrhynchus moelleri, Z. heterogamus, and Umbelopsis isabellina) and the order Mortierellales (Mortierella sp.). As much as 10-30% of the total amount of fungal mycelium remains viable for a long time (one month) under anaerobic conditions.

  15. 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

  16. 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

  17. Conservation of cysteine residues in fungal histidine acid phytases.

    PubMed

    Mullaney, Edward J; Ullah, Abul H J

    2005-03-11

    Amino acid sequence analysis of fungal histidine acid phosphatases displaying phytase activity has revealed a conserved eight-cysteine motif. These conserved amino acids are not directly associated with catalytic function; rather they appear to be essential in the formation of disulfide bridges. Their role is seen as being similar to another eight-cysteine motif recently reported in the amino acid sequence of nearly 500 plant polypeptides. An additional disulfide bridge formed by two cysteines at the N-terminus of all the filamentous ascomycete phytases was also observed. Disulfide bridges are known to increase both stability and heat tolerance in proteins. It is therefore plausible that this extra disulfide bridge contributes to the higher stability found in phytase from some Aspergillus species. To engineer an enhanced phytase for the feed industry, it is imperative that the role of disulfide bridges be taken into cognizance and possibly be increased in number to further elevate stability in this enzyme.

  18. Pichia insulana sp. nov., a novel cactophilic yeast from the Caribbean

    PubMed Central

    Ganter, Philip F.; Cardinali, Gianluigi; Boundy-Mills, Kyria

    2010-01-01

    A novel species of ascomycetous yeast, Pichia insulana sp. nov., is described from necrotic tissue of columnar cacti on Caribbean islands. P. insulana is closely related to and phenotypically very similar to Pichia cactophila and Pichia pseudocactophila. There are few distinctions between these taxa besides spore type, host preference and locality. Sporogenous strains of P. insulana that produce asci with four hat-shaped spores have been found only on Curaçao, whereas there was no evidence of sporogenous P. cactophila from that island. In addition, sequences of the D1/D2 fragment of the large-subunit rDNA from 12 Curaçao strains showed consistent differences from the sequences of the type strains of P. cactophila and P. pseudocactophila. The type strain of P. insulana is TSU00-106.5T (=CBS 11169T =UCD-FST 09-160T). PMID:19661524

  19. Culture independent PCR: an alternative enzyme discovery strategy.

    PubMed

    Jacobsen, Jonas; Lydolph, Magnus; Lange, Lene

    2005-01-01

    Degenerate primers were designed for use in a culture-independent PCR screening of DNA from composite fungal communities, inhabiting residues of corn stovers and leaves. According to similarity searches and alignments amplified clone sequences affiliated with glycosyl hydrolase family 7 and glycosyl hydrolase family 45 though significant sequence divergence was observed. Glycosyl hydrolases from families 7 and 45 play a crucial role in biomass conversion to fuel ethanol. Research in this renewable energy source has two objectives: (i) To contribute to development of a renewable alternative to world's limited crude fossil oil reserves and (ii) to reduce air pollution. Amplification with 18S rDNA-specific primers revealed species within the ascomycetous orders Sordariales and Hypocreales as well as basidiomycetous order Agaricales to be present in these communities. Our study documents the value of culture-independent PCR in microbial diversity studies and could add to development of a new enzyme screening technology.

  20. Pseudomonas syringae Type III Effector HopBB1 Promotes Host Transcriptional Repressor Degradation to Regulate Phytohormone Responses and Virulence.

    PubMed

    Yang, Li; Teixeira, Paulo José Pereira Lima; Biswas, Surojit; Finkel, Omri M; He, Yijian; Salas-Gonzalez, Isai; English, Marie E; Epple, Petra; Mieczkowski, Piotr; Dangl, Jeffery L

    2017-02-08

    Independently evolved pathogen effectors from three branches of life (ascomycete, eubacteria, and oomycete) converge onto the Arabidopsis TCP14 transcription factor to manipulate host defense. However, the mechanistic basis for defense control via TCP14 regulation is unknown. We demonstrate that TCP14 regulates the plant immune system by transcriptionally repressing a subset of the jasmonic acid (JA) hormone signaling outputs. A previously unstudied Pseudomonas syringae (Psy) type III effector, HopBB1, interacts with TCP14 and targets it to the SCF(COI1) degradation complex by connecting it to the JA signaling repressor JAZ3. Consequently, HopBB1 de-represses the TCP14-regulated subset of JA response genes and promotes pathogen virulence. Thus, HopBB1 fine-tunes host phytohormone crosstalk by precisely manipulating part of the JA regulon to avoid pleiotropic host responses while promoting pathogen proliferation.

  1. Geosmithia morbida sp. nov., a new phytopathogenic species living in symbiosis with the walnut twig beetle (Pityophthorus juglandis) on Juglans in USA.

    PubMed

    Kolarík, Miroslav; Freeland, Emily; Utley, Curtis; Tisserat, Ned

    2011-01-01

    Widespread morbidity and mortality of Juglans nigra has occurred in the western USA over the past decade. Tree mortality is the result of aggressive feeding by the walnut twig beetle (Pityophthorus juglandis) and subsequent canker development around beetle galleries caused by a filamentous ascomycete in genus Geosmithia (Ascomycota: Hypocreales). Thirty-seven Geosmithia strains collected from J. californica, J. hindsii, J. major and J. nigra in seven USA states (AZ, CA, CO, ID, OR, UT, WA) were compared with morphological and molecular methods (ITS rDNA sequences). Strains had common characteristics including yellowish conidia en masse, growth at 37 C and absence of growth on Czapek-Dox agar and belonged to a single species described here as G. morbida. Whereas Geosmithia are common saprobes associated with bark beetles attacking hardwoods and conifers worldwide, G. morbida is the first species documented as a plant pathogen.

  2. Molecular characterization of Morchella species from the Western Himalayan region of India.

    PubMed

    Kanwal, Harpreet Kaur; Acharya, Karan; Ramesh, G; Reddy, M Sudhakara

    2011-04-01

    The molecular diversity of thirty-two different Morchella cultures/fruiting bodies, collected from the Western Himalayan region was studied in this investigation. Considerable taxonomic confusion exists regarding many species of Morchella. Although classical taxonomy is helpful in identification for many ascomycetes, morels exhibit considerable morphological diversity and there is disagreement in the identification of morel species. Phylogenetic analyses based on DNA sequences could help in sorting out morel taxonomy which is essential to better define the morel diversity. In this study, sequence analysis revealed that in the Western Himalayan region of India, both yellow (M. crassipes, M. spongiola) and black morels (M. elata, M. angusticeps, and M. gigas) were prominent along with two Verpa species. Phylogenetic analysis by maximum parsimony, maximum likelihood and Bayesian inference revealed two different clades and a clear distinction between yellow and black morels.

  3. The linear plasmid pMC3-2 from Morchella conica is structurally related to adenoviruses.

    PubMed

    Rohe, M; Schrage, K; Meinhardt, F

    1991-12-01

    pMC3-2, one of two linear plasmids localised in the mitochondria of the ascomycete Morchella conica, was completely sequenced. It is 6044 bp in size, contains terminal inverted repeats of 713 and 710 bp length and two open reading frames, ORF1 and ORF2, spanning 2706 bp and 918 bp, respectively. ORF1 probably encodes a viral B-type DNA-polymerase. Concerning ORF2, no homology to any other published protein- or DNA-sequence could be detected. According to the structure of DNA-polymerases, linear plasmids can be grouped into two classes reflecting their localisation either in the cytoplasm or within the mitochondria. In general, the structure of plasmid pMC3-2, as well as of other linear plasmids from filamentous fungi, indicates a close relationship of these genetic elements to adenoviruses.

  4. 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.

  5. Social wasps are a Saccharomyces mating nest.

    PubMed

    Stefanini, Irene; Dapporto, Leonardo; Berná, Luisa; Polsinelli, Mario; Turillazzi, Stefano; Cavalieri, Duccio

    2016-02-23

    The reproductive ecology of Saccharomyces cerevisiae is still largely unknown. Recent evidence of interspecific hybridization, high levels of strain heterozygosity, and prion transmission suggest that outbreeding occurs frequently in yeasts. Nevertheless, the place where yeasts mate and recombine in the wild has not been identified. We found that the intestine of social wasps hosts highly outbred S. cerevisiae strains as well as a rare S. cerevisiae×S. paradoxus hybrid. We show that the intestine of Polistes dominula social wasps favors the mating of S. cerevisiae strains among themselves and with S. paradoxus cells by providing a succession of environmental conditions prompting cell sporulation and spores germination. In addition, we prove that heterospecific mating is the only option for European S. paradoxus strains to survive in the gut. Taken together, these findings unveil the best hidden secret of yeast ecology, introducing the insect gut as an environmental alcove in which crosses occur, maintaining and generating the diversity of the ascomycetes.

  6. Social wasps are a Saccharomyces mating nest

    PubMed Central

    Stefanini, Irene; Dapporto, Leonardo; Berná, Luisa; Polsinelli, Mario; Turillazzi, Stefano; Cavalieri, Duccio

    2016-01-01

    The reproductive ecology of Saccharomyces cerevisiae is still largely unknown. Recent evidence of interspecific hybridization, high levels of strain heterozygosity, and prion transmission suggest that outbreeding occurs frequently in yeasts. Nevertheless, the place where yeasts mate and recombine in the wild has not been identified. We found that the intestine of social wasps hosts highly outbred S. cerevisiae strains as well as a rare S. cerevisiae×S. paradoxus hybrid. We show that the intestine of Polistes dominula social wasps favors the mating of S. cerevisiae strains among themselves and with S. paradoxus cells by providing a succession of environmental conditions prompting cell sporulation and spores germination. In addition, we prove that heterospecific mating is the only option for European S. paradoxus strains to survive in the gut. Taken together, these findings unveil the best hidden secret of yeast ecology, introducing the insect gut as an environmental alcove in which crosses occur, maintaining and generating the diversity of the ascomycetes. PMID:26787874

  7. 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.

  8. The benomyl test as a fundamental diagnostic method for medical mycology.

    PubMed Central

    Summerbell, R C

    1993-01-01

    The fungicide benomyl has long been known to differentially affect major taxonomic groups of fungi. In the present study 163 species or aggregates of closely similar species of medically important fungi and actinomycetes, as well as species commonly isolated as clinical contaminants, were tested to determine their reactions to three concentrations of benomyl. Fungi of basidiomycetous, endomycetous, and microascaceous affinities were highly resistant, including all common yeasts and Geotrichum, Pseudallescheria, Scedosporium, and Scopulariopsis species. Also resistant were fungi of pleosporalean affinities with poroconidial anamorphs, such as Alternaria, Bipolaris, Curvularia, and Exserohilum species. Most other fungi of ascomycetous affinity were moderately to strongly susceptible. Such fungi included dermatophytes; Coccidioides, Blastomyces, and Histoplasma species; Sporothrix schenckii; medically important aspergilli; and "black yeasts." Benomyl testing aided in the provisional identification of nonsporulating mycelia, including common basidiomycetous isolates obtained as contaminants as well as nonsporulating Aspergillus fumigatus from pulmonary sources. PMID:8458952

  9. Fungi as a source of natural coumarins production.

    PubMed

    Costa, Tania Maria; Tavares, Lorena Benathar Ballod; de Oliveira, Débora

    2016-08-01

    Natural coumarins and derivatives are compounds that occur naturally in several organisms (plant, bacteria, and fungi) consisting of fused benzene and α-pyrone rings. These compounds show high technological potential applications in agrochemical, food, pharmaceuticals, and cosmetics industries. Therefore, the need for bulk production of coumarins and the advancement of the chemical and pharmaceutical industries led to the development of synthetic coumarin. However, biotransformation process, synthetic bioengineering, metabolic engineering, and bioinformatics have proven effective in the production of natural products. Today, these biological systems are recognized as green chemistry innovation and business strategy. This review article aims to report the potential of fungi for synthesis of coumarin. These microorganisms are described as a source of natural products capable of synthesizing many bioactive metabolites. The features, classification, properties, and industrial applications of natural coumarins as well as new molecules obtained by basidiomycetes and ascomycetes fungi are reported in order to explore a topic not yet discussed in the scientific literature.

  10. Polyphasic identification of yeasts isolated from bark of cork oak during the manufacturing process of cork stoppers.

    PubMed

    Villa-Carvajal, Mercedes; Coque, Juan José R; Alvarez-Rodríguez, María Luísa; Uruburu, Federico; Belloch, Carmela

    2004-05-01

    A two-step protocol was used for the identification of 52 yeasts isolated from bark of cork oak at initial stages of the manufacturing process of cork stoppers. The first step in the identification was the separation of the isolates into groups by their physiological properties and RFLPs of the ITS-5.8S rRNA gene. The second step was the sequencing of the D1/D2 domains of the 26S rRNA gene of selected isolates representing the different groups. The results revealed a predominance of basidiomycetous yeasts (11 species), while only two species represented the ascomycetous yeasts. Among the basidiomycetous yeasts, members representing the species Rhodosporidium kratochvilovae and Rhodotorula nothofagi, that have been previously isolated from plant material, were the most abundant. Yeasts pertaining to the species Debaryomyces hansenii var. fabryii, Rhodotorula mucilaginosa and Trichosporon mucoides were isolated in small numbers.

  11. Unisexual reproduction enhances fungal competitiveness by promoting habitat exploration via hyphal growth and sporulation.

    PubMed

    Phadke, Sujal S; Feretzaki, Marianna; Heitman, Joseph

    2013-08-01

    Unisexual reproduction is a novel homothallic sexual cycle recently discovered in both ascomycetous and basidiomycetous pathogenic fungi. It is a form of selfing that induces the yeast-to-hyphal dimorphic transition in isolates of the α mating type of the human fungal pathogen Cryptococcus neoformans. Unisexual reproduction may benefit the pathogen by facilitating sexual reproduction in the absence of the opposite a mating type and by generating infectious propagules called basidiospores. Here, we report an independent potential selective advantage of unisexual reproduction beyond genetic exchange and recombination. We competed a wild-type strain capable of undergoing unisexual reproduction with mutants defective in this developmental pathway and found that unisexual reproduction provides a considerable dispersal advantage through hyphal growth and sporulation. Our results show that unisexual reproduction may serve to facilitate access to both nutrients and potential mating partners and may provide a means to maintain the capacity for dimorphic transitions in the environment.

  12. Dataset of the Botrytis cinerea phosphoproteome induced by different plant-based elicitors.

    PubMed

    Liñeiro, Eva; Chiva, Cristina; Cantoral, Jesús M; Sabido, Eduard; Fernández-Acero, Francisco Javier

    2016-06-01

    Phosphorylation is one of the main post-translational modification (PTM) involved in signaling network in the ascomycete Botrytis cinerea, one of the most relevant phytopathogenic fungus. The data presented in this article provided a differential mass spectrometry-based analysis of the phosphoproteome of B. cinerea under two different phenotypical conditions induced by the use of two different elicitors: glucose and deproteinized Tomate Cell Walls (TCW). A total 1138 and 733 phosphoproteins were identified for glucose and TCW culture conditions respectively. Raw data are deposited at the ProteomeXchange Consortium via the PRIDE partner repository with the data set identifier (PRIDE: http://www.ebi.ac.uk/pride/archive/projects/PXD003099). Further interpretation and discussion of these data are provided in our research article entitled "Phosphoproteome analysis of B.cinerea in response to different plant-based elicitors" (Liñeiro et al., 2016) [1].

  13. The influence of Aster x salignus Willd. Invasion on the diversity of soil yeast communities

    NASA Astrophysics Data System (ADS)

    Glushakova, A. M.; Kachalkin, A. V.; Chernov, I. Yu.

    2016-07-01

    The annual dynamics of yeast communities were studied in the soddy-podzolic soil under the thickets of Aster x salignus Willd., one of the widespread invasive plant species in central Russia. Yeast groups in the soils under continuous aster thickets were found to differ greatly from the yeast communities in the soils under the adjacent indigenous meadow vegetation. In both biotopes the same species ( Candida vartiovaarae, Candida sake, and Cryptococcus terreus) are dominants. However, in the soils under indigenous grasses, eurybiontic yeasts Rhodotorula mucilaginosa, which almost never occur in the soil under aster, are widespread. In the soil under aster, the shares of other typical epiphytic and pedobiontic yeast fungi (ascomycetic species Wickerhamomyces aniomalus, Barnettozyma californica and basidiomycetic species Cystofilobasidium macerans, Guehomyces pullulans) significantly increase. Thus, the invasion of Aster x salignus has a clear effect on soil yeast complexes reducing their taxonomic and ecological diversity.

  14. Novel Endorna-like viruses, including three with two open reading frames, challenge the membership criteria and taxonomy of the Endornaviridae.

    PubMed

    Ong, Jamie W L; Li, Hua; Sivasithamparam, Krishnapillai; Dixon, Kingsley W; Jones, Michael G K; Wylie, Stephen J

    2016-12-01

    Viruses associated with wild orchids and their mycorrhizal fungi are poorly studied. Using a shotgun sequencing approach, we identified eight novel endornavirus-like genome sequences from isolates of Ceratobasidium fungi isolated from pelotons within root cortical cells of wild indigenous orchid species Microtis media, Pterostylis sanguinea and an undetermined species of Pterostylis in Western Australia. They represent the first endornaviruses to be described from orchid mycorrhizal fungi and from the Australian continent. Five of the novel endornaviruses were detected from one Ceratobasidium isolate collected from one Pterostylis plant. The partial and complete viral replicases shared low (9-30%) identities with one another and with endornaviruses described from elsewhere. Four had genome lengths greater than those of previously described endornaviruses, two resembled ascomycete-infecting endornaviruses, and unlike currently described endornaviruses, three had two open reading frames. The unusual features of these new viruses challenge current taxonomic criteria for membership of the family Endornaviridae.

  15. Paleomycology of the Princeton Chert II. Dark-septate fungi in the aquatic angiosperm Eorhiza arnoldii indicate a diverse assemblage of root-colonizing fungi during the Eocene.

    PubMed

    Klymiuk, Ashley A; Taylor, Thomas N; Taylor, Edith L; Krings, Michael

    2013-01-01

    Tissues of the extinct aquatic or emergent angiosperm, Eorhiza arnoldii incertae sedis, were extensively colonized by microfungi, and in this study we report the presence of several types of sterile mycelia. In addition to inter- and intracellular proliferation of regular septate hyphae, the tissues contain monilioid hyphae with intercalary branching. These filamentous mycelia are spatially associated with two distinct morphotypes of intracellular microsclerotia. These quiescent structures are morphologically similar to loose and cerebriform microsclerotia found within the living tissues of some plants, which have been attributed to an informal assemblage of dematiaceous ascomycetes, the dark-septate endophytes. While there are significant challenges to interpreting the ecology of fossilized fungi, these specimens provide evidence for asymptomatic endophytic colonization of the rooting structures of a 48.7 million year old aquatic angiosperm.

  16. Pathobiology of Pneumocystis pneumonia: life cycle, cell wall and cell signal transduction.

    PubMed

    Skalski, Joseph H; Kottom, Theodore J; Limper, Andrew H

    2015-09-01

    Pneumocystis is a genus of ascomycetous fungi that are highly morbid pathogens in immunosuppressed humans and other mammals. Pneumocystis cannot easily be propagated in culture, which has greatly hindered understanding of its pathobiology. The Pneumocystis life cycle is intimately associated with its mammalian host lung environment, and life cycle progression is dependent on complex interactions with host alveolar epithelial cells and the extracellular matrix. The Pneumocystis cell wall is a varied and dynamic structure containing a dominant major surface glycoprotein, β-glucans and chitins that are important for evasion of host defenses and stimulation of the host immune system. Understanding of Pneumocystis cell signaling pathways is incomplete, but much has been deduced by comparison of the Pneumocystis genome with homologous genes and proteins in related fungi. In this mini-review, the pathobiology of Pneumocystis is reviewed, with particular focus on the life cycle, cell wall components and cell signal transduction.

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

    PubMed Central

    Binder, Ulrike; Benčina, 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

  18. Proteomic analysis of Metarhizium anisopliae secretion in the presence of the insect pest Callosobruchus maculatus.

    PubMed

    Murad, André M; Noronha, Eliane F; Miller, Robert N G; Costa, Fabio T; Pereira, Caroline D; Mehta, Angela; Caldas, Ruy A; Franco, Octávio L

    2008-12-01

    Crop improvement in agriculture generally focuses on yield, seed quality and nutritional characteristics, as opposed to resistance to biotic stresses. Consequently, natural antifeedant toxins are often rare in seed material, with commercial crops being prone to insect pest predation. In the specific case of cowpea (Vigna unguiculata), smallholder cropping is affected by insect pests that reproduce inside the stored seeds. Entomopathogenic organisms can offer an alternative to conventional pesticides for pest control, producing hydrolases that degrade insect exoskeleton. In this study, protein secretions of the ascomycete Metarhizium anisopliae, which conferred bioinsecticidal activity against Callosobruchus maculatus, were characterized via 2D electrophoresis and mass spectrometry. Proteases, reductases and acetyltransferase enzymes were detected. These may be involved in degradation and nutrient uptake from dehydrated C. maculatus. Proteins identified in this work allowed description of metabolic pathways. Their potential applications in biotechnology include both novel compound development and production of genetically modified plants resistant to insect pests.

  19. Review of Naturopathy of Medical Mushroom, Ophiocordyceps Sinensis, in Sexual Dysfunction

    PubMed Central

    Jiraungkoorskul, Kanitta; Jiraungkoorskul, Wannee

    2016-01-01

    Sexual dysfunctions including desire, arousal, orgasm, and pain disorders are increasing worldwide due to etiological factors and aging. Several types of treatment are claimed in modern medicine, but they have serious side effects and higher costs. In fact, alternative approaches, such as the intake of plants, fungi, and insects, or their extracts, have also been practiced to enhance sexuality and ameliorate illness with notable successes. However, the scientific evidence related to the mechanisms and efficacy of these alternative medicines is both scarce and all too often unconvincing. Ophiocordyceps sinensis is an Ascomycetes fungus parasitic to Lepidoptera larvae, and has long been used as medicine to treat many illnesses and promote longevity in Chinese society. Previous investigations have shown that O. sinensis has many pharmacological activities. This review has focused on illustrating that O. sinensis can enhance libido and sexual performance, and can restore impaired reproductive functions, such as impotency or infertility, in both sexes. PMID:27041868

  20. ent-Kaurene and squalene synthesis in Fusarium fujikuroi cell-free extracts.

    PubMed

    Fernández-Martín, R; Domenech, C; Cerdá-Olmedo, E; Avalos, J

    2000-08-01

    Sterols and gibberellins are the main terpenoids in the Ascomycete Fusarium fujikuroi. Their respective precursors squalene and ent-kaur-16-ene (henceforth called kaurene) were the main terpenoids synthesised from radioactive mevalonate by extracts of F. fujikuroi in vitro. Kaurene predominated when the extracts were obtained from mycelia engaged in gibberellin production. Squalene predominated in all other cases, and particularly when the extracts were obtained from mutants with various defects in gibberellin synthesis or nitrogen-fed wild-type cultures. New protein synthesis was required to maintain the production of gibberellins in vivo and of kaurene in vitro, but not to maintain the capacity to produce squalene in vitro. Addition of a nitrogen source to cultures engaged in gibberellin production caused a large, transient increase in the mycelial concentration of L-glutamine and abolished the accumulation of gibberellins immediately and the capacity to produce kaurene later.

  1. Sesquiterpenes from the conifer root rot pathogen Heterobasidion occidentale.

    PubMed

    Hansson, David; Menkis, Audrius; Himmelstrand, Kajsa; Thelander, Mattias; Olson, Ke; Stenlid, Jan; Karlsson, Magnus; Broberg, Anders

    2012-10-01

    Investigation of the production of secondary metabolites of Heterobasidion occidentale led to the isolation and identification of six sesquiterpenes (illudolone A and B, illudolactone A and B, deoxyfomannosin A and B) along with the well-known sesquiterpene fomannosin and the previously described benzohydrofuran fomannoxin. The structures and relative configurations of the compounds were determined by 1D and 2D NMR spectroscopic analysis as well as by HRMS. Their absolute configuration and biosynthesis were suggested and discussed in relation to fomannosin. Four compounds showed growth inhibiting activity against several basidiomycetes, Phlebiopsis gigantea, Phanerochaete chrysosporium and H. occidentale, and toxicity towards the moss Physcomitrella patens. In addition, one compound displayed activity against the bacterium Variovorax paradoxus as well as against the ascomycete Fusarium oxysporum.

  2. Candida flosculorum sp. nov. and Candida floris sp. nov., two yeast species associated with tropical flowers.

    PubMed

    Rosa, Carlos A; Pagnocca, Fernando C; Lachance, Marc-André; Ruivo, Carla C C; Medeiros, Adriana O; Pimentel, Mariana R C; Fontenelle, Julio C R; Martins, Rogério P

    2007-12-01

    Two ascomycetous yeast species, Candida flosculorum sp. nov. and Candida floris sp. nov., were isolated from tropical flowers and their associated insects. C. flosculorum was isolated from flower bracts of Heliconia velloziana and Heliconia episcopalis (Heliconiaceae) collected from two Atlantic rain forest sites in Brazil. C. floris was isolated from flowers of Ipomoea sp. (Convolvulaceae) growing on the banks of the river Paraguai in the pantanal ecosystem in Brazil and from an adult of the stingless bee Trigona sp. and a flower of Merremia quinquefolia (Convolvulaceae) in Costa Rica. C. flosculorum belongs to the Metschnikowiaceae clade and C. floris belongs to the Starmerella clade. The type strain of C. flosculorum is UFMG-JL13(T) (=CBS 10566(T)=NRRL Y-48258(T)) and the type strain of C. floris is UWO(PS) 00-226.2(T) (=CBS 10593(T)=NRRL Y-48255(T)).

  3. 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

  4. Evaluation of Paecilomyces variotii potential in bioethanol production from lignocellulose through consolidated bioprocessing.

    PubMed

    Zerva, Anastasia; Savvides, Alexander L; Katsifas, Efstathios A; Karagouni, Amalia D; Hatzinikolaou, Dimitris G

    2014-06-01

    The ascomycete Paecillomyces variotii was evaluated for the first time as a candidate species for the production of bioethanol from lignocellulose through consolidated bioprocessing (CBP) approaches. The examined strain (ATHUM 8891) revealed all the necessary phenotypic characteristics required for 2nd generation biofuel production. The fungus is able to efficiently ferment glucose and xylose to ethanol, with yields close to the theoretical maximum. Nitrogen supplementation greatly affected ethanol production with nitrate-nitrogen presenting the best results. Notably, ethanol yield on xylose fermentation was higher than that of glucose, while in co-fermentation of glucose-xylose mixtures no distinguished diauxic behavior was observed. Furthermore, the fungus seems to possess the necessary enzyme factory for the degradation of lignocellulosic biomass, as it was able to grow and produce ethanol on common agro-industrial derivatives. Overall, the results of our study indicate that P. variotii is a new and possibly powerful candidate for CBP applications.

  5. Small genetic differences between ericoid mycorrhizal fungi affect nitrogen uptake by Vaccinium.

    PubMed

    Grelet, Gwen-Aëlle; Meharg, Andrew A; Duff, Elizabeth I; Anderson, Ian C; Alexander, Ian J

    2009-01-01

    Ericoid mycorrhizal fungi have been shown to differ in their pattern of nitrogen (N) use in pure culture. Here, we investigate whether this functional variation is maintained in symbiosis using three ascomycetes from a clade not previously shown to include ericoid mycorrhizal taxa. Vaccinium macrocarpon and Vaccinium vitis-idaea were inoculated with three fungal strains known to form coils in Vaccinium roots, which differed in their patterns of N use in liquid culture. (15)N was used to trace the uptake of -N, -N and glutamine-N into shoots. (15)N transfer differed among the three fungal strains, including two that had identical internal transcribed spacer (ITS) sequences, and was quantitatively related to fungal growth in liquid culture at low carbon availability. These results demonstrate that functional differences among closely related ericoid mycorrhizal fungi are maintained in symbiosis with their hosts, and suggest that N transfer to plant shoots in ericoid mycorrhizas is under fungal control.

  6. Transcriptome analysis of the honey bee fungal pathogen, Ascosphaera apis: implications for host pathogenesis

    PubMed Central

    2012-01-01

    Background We present a comprehensive transcriptome analysis of the fungus Ascosphaera apis, an economically important pathogen of the Western honey bee (Apis mellifera) that causes chalkbrood disease. Our goals were to further annotate the A. apis reference genome and to identify genes that are candidates for being differentially expressed during host infection versus axenic culture. Results We compared A. apis transcriptome sequence from mycelia grown on liquid or solid media with that dissected from host-infected tissue. 454 pyrosequencing provided 252 Mb of filtered sequence reads from both culture types that were assembled into 10,087 contigs. Transcript contigs, protein sequences from multiple fungal species, and ab initio gene predictions were included as evidence sources in the Maker gene prediction pipeline, resulting in 6,992 consensus gene models. A phylogeny based on 12 of these protein-coding loci further supported the taxonomic placement of Ascosphaera as sister to the core Onygenales. Several common protein domains were less abundant in A. apis compared with related ascomycete genomes, particularly cytochrome p450 and protein kinase domains. A novel gene family was identified that has expanded in some ascomycete lineages, but not others. We manually annotated genes with homologs in other fungal genomes that have known relevance to fungal virulence and life history. Functional categories of interest included genes involved in mating-type specification, intracellular signal transduction, and stress response. Computational and manual annotations have been made publicly available on the Bee Pests and Pathogens website. Conclusions This comprehensive transcriptome analysis substantially enhances our understanding of the A. apis genome and its expression during infection of honey bee larvae. It also provides resources for future molecular studies of chalkbrood disease and ultimately improved disease management. PMID:22747707

  7. Regulatory Genes Controlling Fatty Acid Catabolism and Peroxisomal Functions in the Filamentous Fungus Aspergillus nidulans†

    PubMed Central

    Hynes, Michael J.; Murray, Sandra L.; Duncan, Anna; Khew, Gillian S.; Davis, Meryl A.

    2006-01-01

    The catabolism of fatty acids is important in the lifestyle of many fungi, including plant and animal pathogens. This has been investigated in Aspergillus nidulans, which can grow on acetate and fatty acids as sources of carbon, resulting in the production of acetyl coenzyme A (CoA). Acetyl-CoA is metabolized via the glyoxalate bypass, located in peroxisomes, enabling gluconeogenesis. Acetate induction of enzymes specific for acetate utilization as well as glyoxalate bypass enzymes is via the Zn2-Cys6 binuclear cluster activator FacB. However, enzymes of the glyoxalate bypass as well as fatty acid beta-oxidation and peroxisomal proteins are also inducible by fatty acids. We have isolated mutants that cannot grow on fatty acids. Two of the corresponding genes, farA and farB, encode two highly conserved families of related Zn2-Cys6 binuclear proteins present in filamentous ascomycetes, including plant pathogens. A single ortholog is found in the yeasts Candida albicans, Debaryomyces hansenii, and Yarrowia lipolytica, but not in the Ashbya, Kluyveromyces, Saccharomyces lineage. Northern blot analysis has shown that deletion of the farA gene eliminates induction of a number of genes by both short- and long-chain fatty acids, while deletion of the farB gene eliminates short-chain induction. An identical core 6-bp in vitro binding site for each protein has been identified in genes encoding glyoxalate bypass, beta-oxidation, and peroxisomal functions. This sequence is overrepresented in the 5′ region of genes predicted to be fatty acid induced in other filamentous ascomycetes, C. albicans, D. hansenii, and Y. lipolytica, but not in the corresponding genes in Saccharomyces cerevisiae. PMID:16682457

  8. Dynamics of fungal communities in bulk and maize rhizosphere soil in the tropics.

    PubMed

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

    2003-07-01

    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.

  9. 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

  10. A rock-inhabiting ancestor for mutualistic and pathogen-rich fungal lineages.

    PubMed

    Gueidan, C; Villaseñor, C R; de Hoog, G S; Gorbushina, A A; Untereiner, W A; Lutzoni, F

    2008-01-01

    Rock surfaces are unique terrestrial habitats in which rapid changes in the intensity of radiation, temperature, water supply and nutrient availability challenge the survival of microbes. A specialised, but diverse group of free-living, melanised fungi are amongst the persistent settlers of bare rocks. Multigene phylogenetic analyses were used to study relationships of ascomycetes from a variety of substrates, with a dataset including a broad sampling of rock dwellers from different geographical locations. Rock-inhabiting fungi appear particularly diverse in the early diverging lineages of the orders Chaetothyriales and Verrucariales. Although these orders share a most recent common ancestor, their lifestyles are strikingly different. Verrucariales are mostly lichen-forming fungi, while Chaetothyriales, by contrast, are best known as opportunistic pathogens of vertebrates (e.g. Cladophialophora bantiana and Exophiala dermatitidis, both agents of fatal brain infections) and saprophytes. The rock-dwelling habit is shown here to be key to the evolution of these two ecologically disparate orders. The most recent common ancestor of Verrucariales and Chaetothyriales is reconstructed as a non-lichenised rock-inhabitant. Ancestral state reconstructions suggest Verrucariales as one of the independent ascomycetes group where lichenisation has evolved on a hostile rock surface that might have favored this shift to a symbiotic lifestyle. Rock-inhabiting fungi are also ancestral to opportunistic pathogens, as they are found in the early diverging lineages of Chaetothyriales. In Chaetothyriales and Verrucariales, specific morphological and physiological traits (here referred to as extremotolerance) evolved in response to stresses in extreme conditions prevailing on rock surfaces. These factors facilitated colonisation of various substrates including the brains of vertebrates by opportunistic fungal pathogens, as well as helped establishment of a stable lichen symbiosis.

  11. A rock-inhabiting ancestor for mutualistic and pathogen-rich fungal lineages

    PubMed Central

    Gueidan, C.; Villaseñor, C. R.; de Hoog, G. S.; Gorbushina, A. A.; Untereiner, W. A.; Lutzoni, F.

    2008-01-01

    Rock surfaces are unique terrestrial habitats in which rapid changes in the intensity of radiation, temperature, water supply and nutrient availability challenge the survival of microbes. A specialised, but diverse group of free-living, melanised fungi are amongst the persistent settlers of bare rocks. Multigene phylogenetic analyses were used to study relationships of ascomycetes from a variety of substrates, with a dataset including a broad sampling of rock dwellers from different geographical locations. Rock-inhabiting fungi appear particularly diverse in the early diverging lineages of the orders Chaetothyriales and Verrucariales. Although these orders share a most recent common ancestor, their lifestyles are strikingly different. Verrucariales are mostly lichen-forming fungi, while Chaetothyriales, by contrast, are best known as opportunistic pathogens of vertebrates (e.g. Cladophialophora bantiana and Exophiala dermatitidis, both agents of fatal brain infections) and saprophytes. The rock-dwelling habit is shown here to be key to the evolution of these two ecologically disparate orders. The most recent common ancestor of Verrucariales and Chaetothyriales is reconstructed as a non-lichenised rock-inhabitant. Ancestral state reconstructions suggest Verrucariales as one of the independent ascomycetes group where lichenisation has evolved on a hostile rock surface that might have favored this shift to a symbiotic lifestyle. Rock-inhabiting fungi are also ancestral to opportunistic pathogens, as they are found in the early diverging lineages of Chaetothyriales. In Chaetothyriales and Verrucariales, specific morphological and physiological traits (here referred to as extremotolerance) evolved in response to stresses in extreme conditions prevailing on rock surfaces. These factors facilitated colonisation of various substrates including the brains of vertebrates by opportunistic fungal pathogens, as well as helped establishment of a stable lichen symbiosis. PMID

  12. 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

  13. Colorimetric characterization for comparative analysis of fungal pigments and natural food colorants.

    PubMed

    Mapari, Sameer A S; Meyer, Anne S; Thrane, Ulf

    2006-09-20

    Exogenous pigments produced by ascomycetous filamentous fungi belonging to the genera Penicillium, Epicoccum, and Monascus, preselected based on chemotaxonomic knowledge, have been extracted and characterized by quantitative colorimetry. The color characteristics of the fungal extracts were compared to water soluble natural colorants derived from sources currently in use. The tested fungal extracts also included some commercially available Monascus colorants. The a values for the fungal extracts were found to be both positive and negative, the b values were found to be positive, while the hue angles of the fungal color extracts ranged from 40 to 110 indicating the color distribution of fungal extracts over the red-orange-yellow region of the CIELAB color space. The fungal extracts exhibited additional color hues in the red spectrum and similar hues in the yellow spectrum as compared to the reference natural colorants. They were also found to be similar or brighter in terms of chroma to some of the reference natural colorants. Principal component analysis was performed to group and distinguish different colors based on the a and b values. The fungal color extracts could be grouped in accordance with the similarity or difference in the color to those of the existing natural colorants. The diversity of colors was not only found among different fungal genera and/or species but also within the same species on changing the media. There was a marked change in the color composition of the extracts resulting in relatively different hues. Our results, thus, indicate that there exists pigment-producing genera of ascomycetous fungi other than Monascus that produce color shades in the red and the yellow spectra in addition or similar to reference colorants. These color shades could add to the color palette of the natural colorants currently in use. In addition, the multivariate approach in distinguishing and classifying the colorants was shown to be a very useful tool in

  14. Identification of the CRE-1 Cellulolytic Regulon in Neurospora crassa

    PubMed Central

    Sun, Jianping; Glass, N. Louise

    2011-01-01

    Background In filamentous ascomycete fungi, the utilization of alternate carbon sources is influenced by the zinc finger transcription factor CreA/CRE-1, which encodes a carbon catabolite repressor protein homologous to Mig1 from Saccharomyces cerevisiae. In Neurospora crassa, deletion of cre-1 results in increased secretion of amylase and β-galactosidase. Methodology/Principal Findings Here we show that a strain carrying a deletion of cre-1 has increased cellulolytic activity and increased expression of cellulolytic genes during growth on crystalline cellulose (Avicel). Constitutive expression of cre-1 complements the phenotype of a N. crassa Δcre-1 strain grown on Avicel, and also results in stronger repression of cellulolytic protein secretion and enzyme activity. We determined the CRE-1 regulon by investigating the secretome and transcriptome of a Δcre-1 strain as compared to wild type when grown on Avicel versus minimal medium. Chromatin immunoprecipitation-PCR of putative target genes showed that CRE-1 binds to only some adjacent 5′-SYGGRG-3′ motifs, consistent with previous findings in other fungi, and suggests that unidentified additional regulatory factors affect CRE-1 binding to promoter regions. Characterization of 30 mutants containing deletions in genes whose expression level increased in a Δcre-1 strain under cellulolytic conditions identified novel genes that affect cellulase activity and protein secretion. Conclusions/Significance Our data provide comprehensive information on the CRE-1 regulon in N. crassa and contribute to deciphering the global role of carbon catabolite repression in filamentous ascomycete fungi during plant cell wall deconstruction. PMID:21980519

  15. 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.

  16. Divergent and Convergent Evolution of Fungal Pathogenicity

    PubMed Central

    Shang, Yanfang; Xiao, Guohua; Zheng, Peng; Cen, Kai; Zhan, Shuai; Wang, Chengshu

    2016-01-01

    Fungal pathogens of plants and animals have multifarious effects; they cause devastating damages to agricultures, lead to life-threatening diseases in humans, or induce beneficial effects by reducing insect pest populations. Many virulence factors have been determined in different fungal pathogens; however, the molecular determinants contributing to fungal host selection and adaptation are largely unknown. In this study, we sequenced the genomes of seven ascomycete insect pathogens and performed the genome-wide analyses of 33 species of filamentous ascomycete pathogenic fungi that infect insects (12 species), plants (12), and humans (9). Our results revealed that the genomes of plant pathogens encode more proteins and protein families than the insect and human pathogens. Unexpectedly, more common orthologous protein groups are shared between the insect and plant pathogens than between the two animal group pathogens. We also found that the pathogenicity of host-adapted fungi evolved multiple times, and that both divergent and convergent evolutions occurred during pathogen–host cospeciation thus resulting in protein families with similar features in each fungal group. However, the role of phylogenetic relatedness on the evolution of protein families and therefore pathotype formation could not be ruled out due to the effect of common ancestry. The evolutionary correlation analyses led to the identification of different protein families that correlated with alternate pathotypes. Particularly, the effector-like proteins identified in plant and animal pathogens were strongly linked to fungal host adaptation, suggesting the existence of similar gene-for-gene relationships in fungus–animal interactions that has not been established before. These results well advance our understanding of the evolution of fungal pathogenicity and the factors that contribute to fungal pathotype formation. PMID:27071652

  17. 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

  18. The Genome of Nectria haematococca: Contribution of Supernumerary Chromosomes to Gene Expansion

    PubMed Central

    Kuo, Alan; Wasmann, Catherine C.; Grimwood, Jane; Schmutz, Jeremy; Taga, Masatoki; White, Gerard J.; Zhou, Shiguo; Schwartz, David C.; Freitag, Michael; Ma, Li-jun; Danchin, Etienne G. J.; Henrissat, Bernard; Coutinho, Pedro M.; Nelson, David R.; Straney, Dave; Napoli, Carolyn A.; Barker, Bridget M.; Gribskov, Michael; Rep, Martijn; Kroken, Scott; Molnár, István; Rensing, Christopher; Kennell, John C.; Zamora, Jorge; Farman, Mark L.; Selker, Eric U.; Salamov, Asaf; Shapiro, Harris; Pangilinan, Jasmyn; Lindquist, Erika; Lamers, Casey; Grigoriev, Igor V.; Geiser, David M.; Covert, Sarah F.; Temporini, Esteban; VanEtten, Hans D.

    2009-01-01

    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

  19. The Cryptococcus neoformans Alkaline Response Pathway: Identification of a Novel Rim Pathway Activator

    PubMed Central

    Ost, Kyla S.; O’Meara, Teresa R.; Huda, Naureen; Esher, Shannon K.; Alspaugh, J. Andrew

    2015-01-01

    The Rim101/PacC transcription factor acts in a fungal-specific signaling pathway responsible for sensing extracellular pH signals. First characterized in ascomycete fungi such as Aspergillus nidulans and Saccharomyces cerevisiae, the Rim/Pal pathway maintains conserved features among very distantly related fungi, where it coordinates cellular adaptation to alkaline pH signals and micronutrient deprivation. However, it also directs species-specific functions in fungal pathogens such as Cryptococcus neoformans, where it controls surface capsule expression. Moreover, disruption of the Rim pathway central transcription factor, Rim101, results in a strain that causes a hyper-inflammatory response in animal infection models. Using targeted gene deletions, we demonstrate that several genes encoding components of the classical Rim/Pal pathway are present in the C. neoformans genome. Many of these genes are in fact required for Rim101 activation, including members of the ESCRT complex (Vps23 and Snf7), ESCRT-interacting proteins (Rim20 and Rim23), and the predicted Rim13 protease. We demonstrate that in neutral/alkaline pH, Rim23 is recruited to punctate regions on the plasma membrane. This change in Rim23 localization requires upstream ESCRT complex components but does not require other Rim101 proteolysis components, such as Rim20 or Rim13. Using a forward genetics screen, we identified the RRA1 gene encoding a novel membrane protein that is also required for Rim101 protein activation and, like the ESCRT complex, is functionally upstream of Rim23-membrane localization. Homologs of RRA1 are present in other Cryptococcus species as well as other basidiomycetes, but closely related genes are not present in ascomycetes. These findings suggest that major branches of the fungal Kingdom developed different mechanisms to sense and respond to very elemental extracellular signals such as changing pH levels. PMID:25859664

  20. Current understanding on Villosiclava virens, a unique flower-infecting fungus causing rice false smut disease.

    PubMed

    Fan, Jing; Yang, Juan; Wang, Yu-Qiu; Li, Guo-Bang; Li, Yan; Huang, Fu; Wang, Wen-Ming

    2016-12-01

    Villosiclava virens (Vv) is an ascomycete fungal pathogen that causes false smut disease in rice. Recent reports have revealed some interesting aspects of the enigmatic pathogen to address the question of why it specifically infects rice flowers and converts a grain into a false smut ball. Comparative and functional genomics have suggested specific adaptation of Vv in the colonization of rice flowers. Anatomical studies have disclosed that Vv specifically infects rice stamen filaments before heading and intercepts seed formation. In addition, Vv can occupy the whole inner space of a spikelet embracing all floral organs and activate the rice grain-filling network, presumably for nutrient acquisition to support the development of the false smut ball. This profile provides a general overview of the rice false smut pathogen, and summarizes advances in the Vv life cycle, genomics and genetics, and the molecular Vv-rice interaction. Current understandings of the Vv-rice pathosystem indicate that it is a unique and interesting system which can enrich the study of plant-pathogen interactions. Taxonomy: Ustilaginoidea virens is the anamorph form of the pathogen (Kingdom Fungi; Phylum Ascomycota; Class Ascomycetes; Subclass Incertae sedis; Order Incertae sedis; Family Incertae sedis; Genus Ustilaginoidea). The teleomorph form is Villosiclava virens (Kingdom Fungi; Phylum Ascomycota; Class Ascomycetes; Subclass Sordariomycetes; Order Hypocreales; Family Clavicipitaceae; Genus Villosiclava). Disease symptoms: The only visible symptom is the replacement of rice grains by ball-shaped fungal mycelia, namely false smut balls. When maturing, the false smut ball is covered with powdery chlamydospores, and the colour changes to yellowish, yellowish orange, green, olive green and, finally, to greenish black. Sclerotia are often formed on the false smut balls in autumn. Identification and detection: Vv conidia are round to elliptical, measuring 3-5 μm in diameter. Chlamydospores are

  1. Novel root-fungus symbiosis in Ericaceae: sheathed ericoid mycorrhiza formed by a hitherto undescribed basidiomycete with affinities to Trechisporales.

    PubMed

    Vohník, Martin; Sadowsky, Jesse J; Kohout, Petr; Lhotáková, Zuzana; Nestby, Rolf; Kolařík, 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

  2. 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

  3. Amplification of TLO Mediator Subunit Genes Facilitate Filamentous Growth in Candida Spp.

    PubMed Central

    Liu, Zhongle; Moran, Gary P.; Myers, Lawrence C.

    2016-01-01

    Filamentous growth is a hallmark of C. albicans pathogenicity compared to less-virulent ascomycetes. A multitude of transcription factors regulate filamentous growth in response to specific environmental cues. Our work, however, suggests the evolutionary history of C. albicans that resulted in its filamentous growth plasticity may be tied to a change in the general transcription machinery rather than transcription factors and their specific targets. A key genomic difference between C. albicans and its less-virulent relatives, including its closest relative C. dubliniensis, is the unique expansion of the TLO (TeLOmere-associated) gene family in C. albicans. Individual Tlo proteins are fungal-specific subunits of Mediator, a large multi-subunit eukaryotic transcriptional co-activator complex. This amplification results in a large pool of ‘free,’ non-Mediator associated, Tlo protein present in C. albicans, but not in C. dubliniensis or other ascomycetes with attenuated virulence. We show that engineering a large ‘free’ pool of the C. dubliniensis Tlo2 (CdTlo2) protein in C. dubliniensis, through overexpression, results in a number of filamentation phenotypes typically associated only with C. albicans. The amplitude of these phenotypes is proportional to the amount of overexpressed CdTlo2 protein. Overexpression of other C. dubliniensis and C. albicans Tlo proteins do result in these phenotypes. Tlo proteins and their orthologs contain a Mediator interaction domain, and a potent transcriptional activation domain. Nuclear localization of the CdTlo2 activation domain, facilitated naturally by the Tlo Mediator binding domain or artificially through an appended nuclear localization signal, is sufficient for the CdTlo2 overexpression phenotypes. A C. albicans med3 null mutant causes multiple defects including the inability to localize Tlo proteins to the nucleus and reduced virulence in a murine systemic infection model. Our data supports a model in which the

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

    PubMed Central

    Ragon, Marie; Restoux, Gwendal; Moreira, David; Møller, 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

  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

    . 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. 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; Kolařík, 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

  7. Lah is a transmembrane protein and requires Spa10 for stable positioning of Woronin bodies at the septal pore of Aspergillus fumigatus

    PubMed Central

    Leonhardt, Yannik; Carina Kakoschke, Sara; Wagener, Johannes; Ebel, Frank

    2017-01-01

    Woronin bodies are specialized, fungal-specific organelles that enable an immediate closure of septal pores after injury to protect hyphae from excessive cytoplasmic bleeding. In most Ascomycetes, Woronin bodies are tethered at the septal pore by so-called Lah proteins. Using the pathogenic mold Aspergillus fumigatus as a model organism, we show that the C-terminal 288 amino acids of Lah (LahC288) bind to the rim of the septal pore. LahC288 essentially consists of a membrane spanning region and a putative extracellular domain, which are both required for the targeting to the septum. In an A. fumigatus rho4 deletion mutant that has a severe defect in septum formation, LahC288 is recruited to spot-like structures in or at the lateral membrane. This suggests that LahC is recruited before Rho4 starts to govern the septation process. Accordingly, we found that in wild type hyphae Lah is bound before a cross-wall emerges and thus enables a tethering of Woronin bodies at the site of the newly formed septum. Finally, we identified Spa10, a member of a recently described family of septal pore-associated proteins, as a first protein that directly or indirectly interacts with LahC to allow a stable positioning of Woronin bodies at the mature septum. PMID:28281662

  8. 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.

  9. Bilirubin oxidase from Myrothecium verrucaria: X-ray determination of the complete crystal structure and a rational surface modification for enhanced electrocatalytic O2 reduction.

    PubMed

    Cracknell, James A; McNamara, Thomas P; Lowe, Edward D; Blanford, Christopher F

    2011-07-07

    The blue multi-copper oxidase bilirubin oxidase (BOx) from the ascomycete plant pathogen Myrothecium verrucaria (Mv) efficiently catalyses the oxidation of bilirubin to biliverdin, with the concomitant reduction of O(2) to water, a reaction of considerable interest for low-temperature bio-fuel cell applications. We have solved the complete X-ray determined structure of Mv BOx at 2.4 Å resolution, using molecular replacement with the Spore Coat Protein A (CotA) enzyme from Bacillus subtilis (PDB code 1GSK) as a template. The structure reveals an unusual environment around the blue type 1 copper (T1 Cu) that includes two non-coordinating hydrophilic amino acids, asparagine and threonine. The presence of a long, narrow and hydrophilic pocket near the T1 Cu suggests that structure of the substrate-binding site is dynamically determined in vivo. We show that the interaction between the binding pocket of Mv BOx and its highly conjugated natural organic substrate, bilirubin, can be used to stabilise the enzyme on a pyrolytic graphite electrode, more than doubling its electrocatalytic activity relative to the current obtained by simple adsorption of the protein to the carbon surface.

  10. Effects of Secondary Metabolites from the Fungus Septofusidium berolinense on DNA Cleavage Mediated by Human Topoisomerase IIα

    PubMed Central

    Vann, Kendra R.; Ekiz, Güner; Zencir, Sevil; Bedir, Erdal; Topcu, Zeki; Osheroff, Neil

    2016-01-01

    Two metabolites from the ascomycete fungus Septofusidium berolinense were recently identified as having antineoplastic activity [Ekiz, et al. (2015) J. Antibiot. (Tokyo)]. However, the basis for this activity is not known. One of the compounds [3,6-dihydroxy-2-propylbenzaldehyde (GE-1)] is a hydroquinone and the other [2-hydroxymethyl-3-propylcyclohexa-2,5-diene-1,4-dione (GE-2)] is a quinone. Because some hydroquinones and quinones act as topoisomerase II poisons, the effects of GE-1 and GE-2 on DNA cleavage mediated by human topoisomerase IIα were assessed. GE-2 enhanced DNA cleavage ~4–fold and induced scission with a site specificity similar to that of the anticancer drug etoposide. Similar to other quinone-based topoisomerase II poisons, GE-2 displayed several hallmark characteristics of covalent topoisomerase II poisons, including: 1) the inability to poison a topoisomerase IIα construct that lacks the N-terminal domain; 2) the inhibition of DNA cleavage when the compound was incubated with the enzyme prior to the addition of plasmid, and 3) the loss of poisoning activity in the presence of a reducing agent. In contrast to GE-2, GE-1 did not enhance DNA cleavage mediated by topoisomerase IIα except at very high concentrations. However, the activity and potency of the metabolite were dramatically enhanced under oxidizing conditions. Results suggest that topoisomerase IIα may play a role in mediating the cytotoxic effects of these fungal metabolites. PMID:26894873

  11. Reproductive competence: a recurrent logic module in eukaryotic development

    PubMed Central

    Noble, Luke M.; Andrianopoulos, Alex

    2013-01-01

    Developmental competence is the ability to differentiate in response to an appropriate stimulus, as first elaborated by Waddington in relation to organs and tissues. Competence thresholds operate at all levels of biological systems from the molecular (e.g. the cell cycle) to the ontological (e.g. metamorphosis and reproduction). Reproductive competence, an organismal process, is well studied in mammals (sexual maturity) and plants (vegetative phase change), though far less than later stages of terminal differentiation. The phenomenon has also been documented in multiple species of multicellular fungi, mostly in early, disparate literature, providing a clear example of physiological differentiation in the absence of morphological change. This review brings together data on reproductive competence in Ascomycete fungi, particularly the model filamentous fungus Aspergillus nidulans, contrasting mechanisms within Unikonts and plants. We posit reproductive competence is an elementary logic module necessary for coordinated development of multicellular organisms or functional units. This includes unitary multicellular life as well as colonial species both unicellular and multicellular (e.g. social insects such as ants). We discuss adaptive hypotheses for developmental and reproductive competence systems and suggest experimental work to address the evolutionary origins, generality and genetic basis of competence in the fungal kingdom. PMID:23864594

  12. A natural Anopheles-associated Penicillium chrysogenum enhances mosquito susceptibility to Plasmodium infection

    PubMed Central

    Angleró-Rodríguez, Yesseinia I.; Blumberg, Benjamin J.; Dong, Yuemei; Sandiford, Simone L.; Pike, Andrew; Clayton, April M.; Dimopoulos, George

    2016-01-01

    Whereas studies have extensively examined the ability of bacteria to influence Plasmodium infection in the mosquito, the tripartite interactions between non-entomopathogenic fungi, mosquitoes, and Plasmodium parasites remain largely uncharacterized. Here we report the isolation of a common mosquito-associated ascomycete fungus, Penicillium chrysogenum, from the midgut of field-caught Anopheles mosquitoes. Although the presence of Pe. chrysogenum in the Anopheles gambiae midgut does not affect mosquito survival, it renders the mosquito significantly more susceptible to Plasmodium infection through a secreted heat-stable factor. We further provide evidence that the mechanism of the fungus-mediated modulation of mosquito susceptibility to Plasmodium involves an upregulation of the insect’s ornithine decarboxylase gene, which sequesters arginine for polyamine biosynthesis. Arginine plays an important role in the mosquito’s anti-Plasmodium defense as a substrate of nitric oxide production, and its availability therefore has a direct impact on the mosquito’s susceptibility to the parasite. While this type of immunomodulatory mechanism has already been demonstrated in other host-pathogen interaction systems, this is the first report of a mosquito-associated fungus that can suppress the mosquito’s innate immune system in a way that would favor Plasmodium infection and possibly malaria transmission. PMID:27678168

  13. Effects of dry olive residue transformed by Coriolopsis floccosa (Polyporaceae) on the distribution and dynamic of a culturable fungal soil community.

    PubMed

    Siles, José A; González-Menéndez, Victor; Platas, Gonzalo; Sampedro, Inmaculada; García-Romera, Inmaculada; Bills, Gerald F

    2014-04-01

    Dry olive residue (DOR) is an abundant waste product resulting from a two-phase olive oil extraction system. Due to its high organic and mineral content, this material has been proposed as an organic soil amendment; however, it presents phytotoxic and microtoxic properties. Thus, a pretreatment is necessary before its application to soil. Among the strategies for the bioremediation of DOR is treatment with ligninolytic fungi, e.g. Coriolopsis floccosa. This work aimed to assess the diversity of culturable fungi in a soil of the southeast Iberian Peninsula and to evaluate the short-term impact of untransformed and C. floccosa-transformed DOR on soil mycobiota. A total of 1,733 strains were isolated by the particle filtration method and were grouped among 109 different species using morphological and molecular methods. The majority of isolates were ascomycetes and were concentrated among three orders: Hypocreales, Eurotiales and Capnodiales. The soil amendment with untransformed DOR was associated with a depression in fungal diversity at 30 days and changes in the proportions of the major species. However, when C. floccosa-transformed DOR was applied to the soil, changes in fungal diversity were less evident, and species composition was similar to unamended soil.

  14. The natural history of the WRKY–GCM1 zinc fingers and the relationship between transcription factors and transposons

    PubMed Central

    Babu, M. Madan; Iyer, Lakshminarayan M.; Balaji, S.; Aravind, L.

    2006-01-01

    WRKY and GCM1 are metal chelating DNA-binding domains (DBD) which share a four stranded fold. Using sensitive sequence searches, we show that this WRKY–GCM1 fold is also shared by the FLYWCH Zn-finger domain and the DBDs of two classes of Mutator-like element (MULE) transposases. We present evidence that they share a stabilizing core, which suggests a possible origin from a BED finger-like intermediate that was in turn ultimately derived from a C2H2 Zn-finger domain. Through a systematic study of the phyletic pattern, we show that this WRKY–GCM1 superfamily is a widespread eukaryote-specific group of transcription factors (TFs). We identified several new members across diverse eukaryotic lineages, including potential TFs in animals, fungi and Entamoeba. By integrating sequence, structure, gene expression and transcriptional network data, we present evidence that at least two major global regulators belonging to this superfamily in Saccharomyces cerevisiae (Rcs1p and Aft2p) have evolved from transposons, and attained the status of transcription regulatory hubs in recent course of ascomycete yeast evolution. In plants, we show that the lineage-specific expansion of WRKY–GCM1 domain proteins acquired functional diversity mainly through expression divergence rather than by protein sequence divergence. We also use the WRKY–GCM1 superfamily as an example to illustrate the importance of transposons in the emergence of new TFs in different lineages. PMID:17130173

  15. Improvement of fruiting body production in Cordyceps militaris by molecular assessment.

    PubMed

    Zhang, Guozhen; Liang, Yue

    2013-08-01

    Cordyceps militaris is a heterothallic ascomycetous fungus that has been cultivated as a medicinal mushroom. This study was conducted to improve fruiting body production by PCR assessment. Based on single-ascospore isolates selected from wild and cultivated populations, the conserved sequences of α-BOX in MAT1-1 and HMG-BOX in MAT1-2 were used as markers for the detection of mating types by PCR. PCR results indicated that the ratio of mating types is consistent with a theoretical ratio of 1:1 (MAT1-1:MAT1-2) in wild (66:70) and cultivated (71:60) populations. Cross-mating between the opposite mating types produced over fivefold more well-developed fruiting bodies than self- or cross-mating between strains within the same mating type. This study may serve as a valuable reference for artificial culturing of C. militaris and other edible and medicinal mushrooms and may be useful to develop an efficient process for the selection, domestication, and management of strains for industrial-scale production.

  16. A comparison of fungal communities from four salt marsh plants using automated ribosomal intergenic spacer analysis (ARISA).

    PubMed

    Torzilli, Albert P; Sikaroodi, Masoumeh; Chalkley, David; Gillevet, Patrick M

    2006-01-01

    Fungal decomposers are important contributors to the detritus-based food webs of salt marsh ecosystems. Knowing the composition of salt marsh fungal communities is essential in understanding how detritus processing is affected by changes in community dynamics. Automated ribosomal intergenic spacer analysis (ARISA) was used to examine the composition of fungal communities associated with four temperate salt marsh plants, Spartina alterniflora (short and tall forms), Juncus roemerianus, Distichlis spicata and Sarcocornia perennis. Plant tissues were homogenized and subjected to a particle-filtration protocol that yielded 106 microm particulate fractions, which were used as a source of fungal isolates and fungal DNA. Genera identified from sporulating cultures demonstrated that the 106 microm particles from each host plant were reliable sources of fungal DNA for ARISA. Analysis of ARISA data by principal component analysis (PCA), principal coordinate analysis (PCO) and species diversity comparisons indicated that the fungal communities from the two grasses, S. alterniflora and D. spicata were more similar to each other than they were to the distinct communities associated with J. roemerianus and S. perennis. Principal component analysis also showed no consistent, seasonal pattern in the composition of these fungal communities. Comparisons of ARISA fingerprints from the different fungal communities and those from pure cultures of selected Spartina ascomycetes supported the host/substrate specificity observed for the fungal communities.

  17. The Neurospora organelle motor: a distant relative of conventional kinesin with unconventional properties.

    PubMed Central

    Steinberg, G; Schliwa, M

    1995-01-01

    The "conventional" kinesins comprise a conserved family of molecular motors for organelle transport that have been identified in various animal species. Organelle motors from other phyla have not yet been analyzed at the molecular level. Here we report the identification, biochemical and immunological characterization, and molecular cloning of a cytoplasmic motor in a "lower" eukaryote, the Ascomycete fungus Neurospora crassa. This motor, termed Nkin (for Neurospora kinesin), exhibits several unique structural and functional features, including a high rate of microtubule transport, a lack of copurifying light chains, a second P-loop motif, and an overall sequence organization reminiscent of a kinesin-like protein. However, a greater than average sequence homology in the motor domain and the presence of a highly conserved region in the C-terminus identify Nkin as a distant relative of the family of conventional kinesins. A molecular phylogenetic analysis suggests Nkin to have diverged early in the evolution of this family of motors. The discovery of Nkin may help identify domains important for specific biological functions in conventional kinesins. Images PMID:8589459

  18. Three-dimensional organization of three-domain copper oxidases: A review

    NASA Astrophysics Data System (ADS)

    Zhukhlistova, N. E.; Zhukova, Yu. N.; Lyashenko, A. V.; Zaĭtsev, V. N.; Mikhaĭlov, A. M.

    2008-01-01

    “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.

  19. 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.

  20. 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

  1. Sequence diversity of mating-type genes in Phaeosphaeria avenaria.

    PubMed

    Ueng, Peter P; Dai, Qun; Cui, Kai-rong; Czembor, Paweł C; Cunfer, Barry M; Tsang, H; Arseniuk, Edward; Bergstrom, Gary C

    2003-05-01

    Phaeosphaeria avenaria, one of the causal agents of stagonospora leaf blotch diseases in cereals, is composed of two subspecies, P. avenaria f. sp. triticea (Pat) and P. avenaria f. sp. avenaria (Paa). The Pat subspecies was grouped into Pat1-Pat3, based on restriction fragment length polymorphism (RFLP) and ribosomal DNA (rDNA) internal transcribed spacer (ITS) sequences in previous studies. Mating-type genes and their potential use in phylogeny and molecular classification were studied by DNA hybridization and PCR amplification. The majority of Pat1 isolates reported to be homothallic and producing sexual reproduction structures on cultural media had only the MAT1-1 gene. Minor sequence variations were found in the conserved region of MAT1-1 gene in Pat1 isolates. However, both mating-type genes, MAT1-1 and MAT1-2, were identified in P. avenaria isolates represented by ATCC12277 from oats (Paa) and the Pat2 isolates from foxtail barley ( Hordeum jubatum L.). Cluster analyses based on mating-type gene conserved regions revealed that cereal Phaeosphaeria is not phylogenetically closely related to other ascomycetes, including Mycosphaerella graminicola (anamorph Septoria tritici). The sequence diversity of mating-type genes in Pat and Paa supports our previous phylogenetic relationship and molecular classification based on RFLP fingerprinting and rDNA ITS sequences.

  2. 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

  3. Fungal succession in relation to volatile organic compounds emissions from Scots pine and Norway spruce leaf litter-decomposing fungi

    NASA Astrophysics Data System (ADS)

    Isidorov, Valery; Tyszkiewicz, Zofia; Pirożnikow, Ewa

    2016-04-01

    Leaf litter fungi are partly responsible for decomposition of dead material, nutrient mobilization and gas fluxes in forest ecosystems. It can be assumed that microbial destruction of dead plant materials is an important source of volatile organic compounds (VOCs) emitted into the atmosphere from terrestrial ecosystems. However, little information is available on both the composition of fungal VOCs and their producers whose community can be changed at different stages of litter decomposition. The fungal community succession was investigated in a litter bag experiment with Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) needle litter. The succession process can be divided into a several stages controlled mostly by changes in litter quality. At the very first stages of decomposition the needle litter was colonized by ascomycetes which can use readily available carbohydrates. At the later stages, the predominance of Trichoderma sp., the known producers of cellulolytic enzymes, was documented. To investigate the fungi-derived VOCs, eight fungi species were isolated. As a result of gas chromatographic analyses, as many as 75C2sbnd C15 fungal volatile compounds were identified. Most components detected in emissions were very reactive substances: the principal groups of VOCs were formed by monoterpenes, carbonyl compounds and aliphatic alcohols. It was found that production of VOCs by fungi is species specific: only 10 metabolites were emitted into the gas phase by all eight species. The reported data confirm that the leave litter decomposition is important source of reactive organic compounds under the forest canopy.

  4. A Ras GTPase associated protein is involved in the phototropic and circadian photobiology responses in fungi

    PubMed Central

    Polaino, Silvia; Villalobos-Escobedo, José M.; Shakya, Viplendra P. S.; Miralles-Durán, Alejandro; Chaudhary, Suman; Sanz, Catalina; Shahriari, Mahdi; Luque, Eva M.; Eslava, Arturo P.; Corrochano, Luis M.; Herrera-Estrella, Alfredo; Idnurm, Alexander

    2017-01-01

    Light is an environmental signal perceived by most eukaryotic organisms and that can have major impacts on their growth and development. The MadC protein in the fungus Phycomyces blakesleeanus (Mucoromycotina) has been postulated to form part of the photosensory input for phototropism of the fruiting body sporangiophores, but the madC gene has remained unidentified since the 1960s when madC mutants were first isolated. In this study the madC gene was identified by positional cloning. All madC mutant strains contain loss-of-function point mutations within a gene predicted to encode a GTPase activating protein (GAP) for Ras. The madC gene complements the Saccharomyces cerevisiae Ras-GAP ira1 mutant and the encoded MadC protein interacts with P. blakesleeanus Ras homologs in yeast two-hybrid assays, indicating that MadC is a regulator of Ras signaling. Deletion of the homolog in the filamentous ascomycete Neurospora crassa affects the circadian clock output, yielding a pattern of asexual conidiation similar to a ras-1 mutant that is used in circadian studies in N. crassa. Thus, MadC is unlikely to be a photosensor, yet is a fundamental link in the photoresponses from blue light perceived by the conserved White Collar complex with Ras signaling in two distantly-related filamentous fungal species. PMID:28322269

  5. 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

  6. Convergent targeting of a common host protein-network by pathogen effectors from three kingdoms of life.

    PubMed

    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; Ver Loren van Themaat, Emiel; Weigel, Detlef; Schulze-Lefert, Paul; Dangl, Jeffery L; Panstruga, Ralph; Braun, Pascal

    2014-09-10

    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 data set 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 intraspecies and interspecies convergence and several altered immune response phenotypes. Several effectors and the most heavily targeted host protein colocalized in subnuclear 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.

  7. 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.

  8. 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

  9. Cell signaling pathways in Paracoccidioides brasiliensis--inferred from comparisons with other fungi.

    PubMed

    Fernandes, Larissa; Araújo, Marcus A M; Amaral, André; Reis, Viviane Castelo Branco; Martins, Natália F; Felipe, M S

    2005-06-30

    The human fungal pathogen Paracoccidioides brasiliensis is an ascomycete that displays a temperature-dependent dimorphic transition, appearing as a mycelium at 22 degrees C and as a yeast at 37 degrees C, this latter being the virulent form. We report on the in silico search made of the P. brasiliensis transcriptome-expressed sequence tag database for components of signaling pathways previously known to be involved in morphogenesis and virulence in other species of fungi, including Saccharomyces cerevisiae, Cryptococcus neoformans, Candida albicans, and Aspergillus fumigatus. Using this approach, it was possible to identify several protein cascades in P. brasiliensis, such as i) mitogen-activated protein kinase signaling for cell integrity, cell wall construction, pheromone/mating, and osmo-regulation, ii) the cAMP/PKA system, which regulates fungal development and virulence, iii) the Ras protein, which allows cross-talking between cascades, iv) calcium-calmodulin-calcineurin, which controls cell survival under oxidative stress, high temperature, and membrane/cell wall perturbation, and v) the target of rapamycin pathway, controlling cell growth and proliferation. The ways in which P. brasiliensis responds to the environment and modulates the expression of genes required for its survival and virulence can be inferred through comparison with other fungi for which this type of data is already available.

  10. 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

  11. STUDIES ON IMMUNOLOGICAL RELATIONSHIPS AMONG THE PNEUMOCOCCI : III. RELATIONSHIP BETWEEN A VARIETY OF SACCHAROMYCES CEREVISIAE AND THE TYPE II VARIETY OF DIPLOCOCCUS PNEUMONIAE (PNEUMOCOCCUS).

    PubMed

    Sugg, J Y; Neill, J M

    1929-01-31

    The paper reports evidence of an immunological relationship between one variety of Saccharomyces ceremsise and the Type II variety of Diplococcus pneumonix (Pneumococcus). The most convincing data consisted of the reactions of the Type II bacteria with potent antiyeast serum which agglutinated, and protected mice against these pneumococci as well as the average antiserum obtained by immunization of rabbits with Type II bacteria themselves. The reactivity of the antiyeast serum is strictly specific to the Type II variety of Pneumococcus in the sense that it is entirely devoid of antibodies reactive with Type I or III. The results of absorption experiments with both the antiyeast (rabbit) serum and the anti-Type II (horse) serum were the same as those usually obtained in analogous experiments with immunologically related, but not identical, kinds of bacteria. The immunological relationship of the yeast and the Type II pneumococcus is apparently based upon S-anti-S reactions. It represents an example of heterogenetic specificity which is of particular interest because of the wide genetic separation of the pathogenic schizomycete and the saprophytic ascomycete. Data on the individual irregularity in the yeast-agglutinating capacity of serum from non-immunized or "normal" rabbits are presented as experimental facts.

  12. 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

  13. Cold adaptation of fungi obtained from soil and lake sediment in the Skarvsnes ice-free area, Antarctica.

    PubMed

    Tsuji, Masaharu; Fujiu, Seiichi; Xiao, Nan; Hanada, Yuichi; Kudoh, Sakae; Kondo, Hidemasa; Tsuda, Sakae; Hoshino, Tamotsu

    2013-09-01

    A total of 71 isolates were collected from lake sediment and soil surrounding lakes in the Skarvsnes area, Antarctica. Based on ITS region sequence similarity, these isolates were classified to 10 genera. Twenty-three isolates were categorized as ascomycetous fungi from five genera (Embellisia, Phoma, Geomyces, Tetracladium or Thelebolus) and 48 isolates were categorized as basidiomycetous fungi in five genera (Mrakia, Cryptococcus, Dioszegia, Rhodotorula or Leucosporidium). Thirty-five percent of culturable fungi were of the genus Mrakia. Eighteen isolates from eight genera were selected and tested for both antifreeze activity and capacity for growth under temperatures ranging from -1 to 25 °C. Rhodotorula sp. NHT-2 possessed a high degree of sequence homology with R. gracialis, while Leucosporidium sp. BSS-1 possessed a high degree of sequence homology with Leu. antarcticum (Glaciozyma antarctica), and these two isolates demonstrated antifreeze activity. All isolates examined were capable of growth at -1 °C. Mrakia spp., while capable of growth at -1 °C, did not demonstrate any antifreeze activity and exhibited only limited secretion of extracellular polysaccharides. Species of the genus Mrakia possessed high amounts of unsaturated fatty acids, suggesting that members of this genus have adapted to cold environments by increasing their membrane fluidity.

  14. Nematodospora anomalae sp. nov., a novel and D-xylose-fermenting yeast species in the Lodderomyces clade.

    PubMed

    Ren, Yong-Cheng; Liu, Xiao-Jing; Yi, Ze-Hao; Hui, Feng-Li

    2016-10-01

    Three strains of a novel species of ascomycetous yeast were isolated from the beetle species Anomala corpulenta (Scarabaeoidea) collected from the Baotianman and Funiu Mountains of China. These strains produced conjugated asci with a single coiled ascospore. Phylogenetic analysis of the combined sequences of the D1/D2 domains of the large subunit rRNA gene and internal transcribed spacer regions demonstrated that the three strains were closely related to Nematodospora valgi and an undescribed yeast strain, 13Y231. The novel strains could be differentiated from N. valgi CBS 12562T by a 1.6 % sequence divergence (9 substitutions) and from the undescribed yeast strain, 13Y231, by a 1.1 % sequence divergence (6 substitutions) in the D1/D2 sequences. The ITS sequences of these strains displayed more than 4.1 % sequence divergence (12-22 substitutions and 7-8 gaps) from their two closest relatives. Interestingly, all the three strains could ferment d-xylose to ethanol effectively, a rare property among members of the Lodderomyces clade. Therefore, a novel yeast species, Nematodosporaanomalae sp. nov., is proposed to accommodate these strains. The type strain of N.anomalae sp. nov. is NYNU 14914T (=CICC 33059T=CBS 13927T). The MycoBank number is MB 816795.

  15. FTY720 Attenuates Angiotensin II-Induced Podocyte Damage via Inhibiting Inflammatory Cytokines

    PubMed Central

    Su, Ke; Zeng, Ping; Liang, Wei; Luo, Zhengyu; Wang, Yiman; Lv, Xifeng; Han, Qi; Yan, Miao

    2017-01-01

    FTY720, a new chemical substance derived from the ascomycete Isaria sinclairii, is used for treating multiple sclerosis, renal cancer, and asthma. Sphingosine 1-phosphate (S1P) is a bioactive sphingolipid metabolite and exists in red blood cells. FTY720 is a synthetic S1P analog which can block S1P evoking physiological effects. Recently studies show that S1P was participating in activated inflammation cells induced renal injury. The objective of this study was to assess the protective effect of FTY720 on kidney damage and the potential mechanism of FTY720 which alleviate podocyte injury in chronic kidney disease. In this study, we selected 40 patients with IgA nephropathy and examined their clinical characteristics. Ang II-infusion rat renal injury model was established to evaluate the glomeruli and tubulointerstitial lesion. The result showed that the concentration of S1P in serum and urine was positively correlated with IgA nephropathy patients' renal injury. FTY720 could reduce renal histological lesions induced by Ang II-infusion in rats. Moreover, FTY720 decreased S1P synthesis in Ang II-infusion rats via downregulation of inflammatory cytokines including TNF-α and IL-6. In addition, FTY720 alleviated exogenous S1P-induced podocyte damage. In conclusion, FTY720 is able to attenuate S1P-induced podocyte damage via reducing inflammatory cytokines. PMID:28270699

  16. PCR primers specific for the genus Tuber reveal the presence of several truffle species in a truffle-ground.

    PubMed

    Zampieri, Elisa; Mello, Antonietta; Bonfante, Paola; Murat, Claude

    2009-08-01

    Truffles are hypogeous Ascomycete fungi belonging to the genus Tuber and forming fruiting bodies highly prized for their taste and aroma. The identification of the genus Tuber and its species is important to investigate their ecology and avoid fraud in the food market. As genus-specific primers are not available, the aims of this work were (1) to assess the usefulness of the beta-tubulin gene as a DNA barcoding region for designing Tuber genus-specific primers, (2) to test the primers on a range of fruiting bodies, representing a large part of truffle biodiversity and (3) to check their ecological usefulness, applying them to truffle-ground soil. The new primers designed on the beta-tubulin gene were specific to the Tuber genus in nested PCR. When applied to DNA from soils, they gave a positive signal for 23 of 32 soils. Phylogenetic analysis confirmed that the bands corresponded to Tuber and that at least five Tuber species were present in the truffle-ground. beta-tubulin was found to be a good barcoding region for designing Tuber genus-specific primers, detecting a high Tuber diversity in a natural environment. These primers will be useful for understanding truffle ecology and for practical needs in plantation management.

  17. Fine-scale spatial genetic structure of the black truffle (Tuber melanosporum) investigated with neutral microsatellites and functional mating type genes.

    PubMed

    Murat, Claude; Rubini, Andrea; Riccioni, Claudia; De la Varga, Herminia; Akroume, Emila; Belfiori, Beatrice; Guaragno, Marco; Le Tacon, François; Robin, Christophe; Halkett, Fabien; Martin, Francis; Paolocci, Francesco

    2013-07-01

    The genetic structure of ectomycorrhizal (ECM) fungal populations results from both vegetative and sexual propagation. In this study, we have analysed the spatial genetic structure of Tuber melanosporum populations, a heterothallic ascomycete that produces edible fruit bodies. Ectomycorrhizas from oaks and hazels from two orchards were mapped and genotyped using simple sequence repeat markers and the mating type locus. The distribution of the two T. melanosporum mating types was also monitored in the soil. In one orchard, the genetic profiles of the ascocarps were compared with those of the underlying mycorrhizas. A pronounced spatial genetic structure was found. The maximum genet sizes were 2.35 and 4.70 m in the two orchards, with most manifesting a size < 1 m. Few genets persisted throughout two seasons. A nonrandom distribution pattern of the T. melanosporum was observed, resulting in field patches colonized by genets that shared the same mating types. Our findings suggest that competition occurs between genets and provide basic information on T. melanosporum propagation patterns that are relevant for the management of productive truffle orchards.

  18. The Fast-Evolving phy-2 Gene Modulates Sexual Development in Response to Light in the Model Fungus Neurospora crassa

    PubMed Central

    Wang, Zheng; Li, Ning; Li, Jigang; Dunlap, Jay C.; Trail, Frances

    2016-01-01

    ABSTRACT Rapid responses to changes in incident light are critical to the guidance of behavior and development in most species. Phytochrome light receptors in particular play key roles in bacterial physiology and plant development, but their functions and regulation are less well understood in fungi. Nevertheless, genome-wide expression measurements provide key information that can guide experiments that reveal how genes respond to environmental signals and clarify their role in development. We performed functional genomic and phenotypic analyses of the two phytochromes in Neurospora crassa, a fungal model adapted to a postfire environment that experiences dramatically variable light conditions. Expression of phy-1 and phy-2 was low in early sexual development and in the case of phy-2 increased in late sexual development. Under light stimulation, strains with the phytochromes deleted exhibited increased expression of sexual development-related genes. Moreover, under red light, the phy-2 knockout strain commenced sexual development early. In the evolution of phytochromes within ascomycetes, at least two duplications have occurred, and the faster-evolving phy-2 gene has frequently been lost. Additionally, the three key cysteine sites that are critical for bacterial and plant phytochrome function are not conserved within fungal phy-2 homologs. Through the action of phytochromes, transitions between asexual and sexual reproduction are modulated by light level and light quality, presumably as an adaptation for fast asexual growth and initiation of sexual reproduction of N. crassa in exposed postfire ecosystems. PMID:26956589

  19. Tyrosinase expression during black truffle development: from free living mycelium to ripe fruit body.

    PubMed

    Zarivi, Osvaldo; Bonfigli, Antonella; Colafarina, Sabrina; Aimola, Pierpaolo; Ragnelli, Anna Maria; Pacioni, Giovanni; Miranda, Michele

    2011-12-01

    The present work studies the expression of tyrosinase (monophenol:diphenol oxygen oxidoreductase, EC 1.14.18.1) during the development of the black truffle Tuber melanosporum Vittad., an ectomycorrhizal fungus of great biological and economic interest. As widely reported in the literature, melanins and the enzymes that synthesize them, are of paramount importance in fungal development and sexual differentiation. Tyrosinase and laccase are the enzymes that produce melanins from monophenols and diphenols. We have detected tyrosinase expression from the stage of free living mycelium, through the mychorrizal stage and the six fruit body developmental stages by measuring the levels of tyrosinase mRNA by quantitative PCR (q-PCR), spectrophotometry, histochemistry, immunohistochemistry and electrophoresis. Tyrosinase is always expressed, from the free living mycelium to the ripe fruit body developmental stages, when it is very low. The switching off of the tyrosinase gene during T. melanosporum development when the fruit body is ripe and no more cell walls are to be built is discussed in relation of thioflavour production. Specific primers, prepared from the cloned T. melanosporum tyrosinase cDNA were used for the q-PCR and the deduced aminoacid sequences of the CuA and CuB binding sites were compared to those of various ascomycetes and basidiomycetes.

  20. Reconstructing the evolutionary history of gypsy retrotransposons in the Périgord black truffle (Tuber melanosporum Vittad.).

    PubMed

    Payen, Thibaut; Murat, Claude; Martin, Francis

    2016-08-01

    Truffles are ascomycete fungi belonging to genus Tuber, and they form ectomycorrhizal associations with trees and shrubs. Transposable elements constitute more than 50 % of the black Périgord truffle (Tuber melanosporum) genome, which are mainly class 1 gypsy retrotransposons, but their impact on its genome is unknown. The aims of this study are to investigate the diversity of gypsy retrotransposons in this species and their evolutionary history by analysing the reference genome and six resequenced genomes of different geographic accessions. Using the reverse transcriptase sequences, six different gypsy retrotransposon clades were identified. Tmt1 and Tmt6 are the most abundant transposable elements, representing 14 and 13 % of the T. melanosporum genome, respectively. Tmt6 showed a major burst of proliferation between 1 and 4 million years ago, but evidence of more recent transposition was observed. Except for Tmt2, the other clades tend to aggregate, and their mode of transposition excluded the master copy model. This suggests that each new copy has the same probability of transposing as other copies. This study provides a better view of the diversity and dynamic nature of gypsy retrotransposons in T. melanosporum. Even if the major gypsy retrotransposon bursts are old, some elements seem to have transposed recently, suggesting that they may continue to model the truffle genomes.

  1. 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.

  2. Cellular Tracking and Gene Profiling of Fusarium graminearum during Maize Stalk Rot Disease Development Elucidates Its Strategies in Confronting Phosphorus Limitation in the Host Apoplast

    PubMed Central

    Jia, Lei-Jie; Yuan, Ting-Lu; Zhang, Dong; Guo, Yan; Wang, Yufeng; Tang, Wei-Hua

    2016-01-01

    The ascomycete fungus Fusarium graminearum causes stalk rot in maize. We tracked this pathogen’s growth in wound-inoculated maize stalks using a fluorescence-labeled fungal isolate and observed that invasive hyphae grew intercellularly up to 24 h post inoculation, grew intra- and inter-cellularly between 36–48 h, and fully occupied invaded cells after 72 h. Using laser microdissection and microarray analysis, we profiled changes in global gene expression during pathogen growth inside pith tissues of maize stalk from 12 h to six days after inoculation and documented transcriptomic patterns that provide further insights into the infection process. Expression changes in transcripts encoding various plant cell wall degrading enzymes appeared to correlate with inter- and intracellular hyphal growth. Genes associated with 36 secondary metabolite biosynthesis clusters were expressed. Expression of several F. graminearum genes potentially involved in mobilization of the storage lipid triacylglycerol and phosphorus-free lipid biosynthesis were induced during early infection time points, and deletion of these genes caused reduction of virulence in maize stalk. Furthermore, we demonstrated that the F. graminearum betaine lipid synthase 1 (BTA1) gene was necessary and sufficient for production of phosphorus-free membrane lipids, and that deletion of BTA1 interfered with F. graminearum’s ability to advance intercellularly. We conclude that F. graminearum produces phosphorus-free membrane lipids to adapt to a phosphate-limited extracellular microenvironment during early stages of its invasion of maize stalk. PMID:26974960

  3. Cellular Tracking and Gene Profiling of Fusarium graminearum during Maize Stalk Rot Disease Development Elucidates Its Strategies in Confronting Phosphorus Limitation in the Host Apoplast.

    PubMed

    Zhang, Yan; He, Juan; Jia, Lei-Jie; Yuan, Ting-Lu; Zhang, Dong; Guo, Yan; Wang, Yufeng; Tang, Wei-Hua

    2016-03-01

    The ascomycete fungus Fusarium graminearum causes stalk rot in maize. We tracked this pathogen's growth in wound-inoculated maize stalks using a fluorescence-labeled fungal isolate and observed that invasive hyphae grew intercellularly up to 24 h post inoculation, grew intra- and inter-cellularly between 36-48 h, and fully occupied invaded cells after 72 h. Using laser microdissection and microarray analysis, we profiled changes in global gene expression during pathogen growth inside pith tissues of maize stalk from 12 h to six days after inoculation and documented transcriptomic patterns that provide further insights into the infection process. Expression changes in transcripts encoding various plant cell wall degrading enzymes appeared to correlate with inter- and intracellular hyphal growth. Genes associated with 36 secondary metabolite biosynthesis clusters were expressed. Expression of several F. graminearum genes potentially involved in mobilization of the storage lipid triacylglycerol and phosphorus-free lipid biosynthesis were induced during early infection time points, and deletion of these genes caused reduction of virulence in maize stalk. Furthermore, we demonstrated that the F. graminearum betaine lipid synthase 1 (BTA1) gene was necessary and sufficient for production of phosphorus-free membrane lipids, and that deletion of BTA1 interfered with F. graminearum's ability to advance intercellularly. We conclude that F. graminearum produces phosphorus-free membrane lipids to adapt to a phosphate-limited extracellular microenvironment during early stages of its invasion of maize stalk.

  4. 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 ΔFgsch9 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 ΔFgsch9 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 ΔMosch9 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

  5. Comparative Genome Analysis of Filamentous Fungi Reveals Gene Family Expansions Associated with Fungal Pathogenesis

    PubMed Central

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

    2008-01-01

    Fungi and oomycetes are the causal agents of many of the most serious diseases of plants. Here we report a detailed comparative analysis of the genome sequences of thirty-six species of fungi and oomycetes, including seven plant pathogenic species, that aims to explore the common genetic features associated with plant disease-causing species. The predicted translational products of each genome have been clustered into groups of potential orthologues using Markov Chain Clustering and the data integrated into the e-Fungi object-oriented data warehouse (http://www.e-fungi.org.uk/). Analysis of the species distribution of members of these clusters has identified proteins that are specific to filamentous fungal species and a group of proteins found only in plant pathogens. By comparing the gene inventories of filamentous, ascomycetous phytopathogenic and free-living species of fungi, we have identified a set of gene families that appear to have expanded during the evolution of phytopathogens and may therefore serve important roles in plant disease. We have also characterised the predicted set of secreted proteins encoded by each genome and identified a set of protein families which are significantly over-represented in the secretomes of plant pathogenic fungi, including putative effector proteins that might perturb host cell biology during plant infection. The results demonstrate the potential of comparative genome analysis for exploring the evolution of eukaryotic microbial pathogenesis. PMID:18523684

  6. Candida aechmeae sp. nov. and Candida vrieseae sp. nov., novel yeast species isolated from the phylloplane of bromeliads in Southern Brazil.

    PubMed

    Landell, Melissa Fontes; Billodre, Raisa; Ramos, Jesus P; Leoncini, Orílio; Vainstein, Marilene H; Valente, Patrícia

    2010-01-01

    Two novel yeast species, Candida aechmeae sp. nov. and Candida vrieseae sp. nov., were isolated from bromeliads in Itapuã Park, Rio Grande do Sul, Brazil. These species are genetically isolated from all other currently recognized ascomycetous yeasts based on their sequence divergence in the D1/D2 domain of the LSU rRNA gene. C. aechmeae sp. nov. is phylogenetically close to Candida ubatubensis, a species also isolated from bromeliads in Brazil, but the novel species can be differentiated on the basis of differences in the D1/D2 domain and positive results for the assimilation of l-arabinose, raffinose, inulin and citrate. Candida vrieseae sp. nov. is phylogenetically placed in a clade near Candida membranifaciens that is composed of several species associated with insects, but the novel species can be differentiated from them by the D1/D2 and ITS gene sequences, positive results for the assimilation of nitrite and a negative result for the assimilation of ethylamine. The type strain for Candida aechmeae sp. nov. is BI153(T) (=CBS 10831(T)=NRRL Y-48456(T)) and the type strain for C. vrieseae sp. nov. is BI146(T) (=CBS 10829(T)=NRRL Y-48461(T)).

  7. Tandem repeat-tRNA (TRtRNA) PCR method for the molecular typing of non-Saccharomyces subspecies.

    PubMed

    Barquet, Marianne; Martín, Valentina; Medina, Karina; Pérez, Gabriel; Carrau, Francisco; Gaggero, Carina

    2012-01-01

    There is a worldwide trend to understand the impact of non-Saccharomyces yeast species on the process of winemaking. Although the predominant species at the end of the fermentation is Saccharomyces cerevisiae, several non-Saccharomyces species present during the first days of the process can produce and/or release aromas that improve the bouquet and complexity of the final wine. Since no genomic sequences are available for the predominant non-Saccharomyces species selected from grapes or musts (Hanseniaspora uvarum, Hanseniaspora vineae, Hanseniaspora opuntiae, Metschnikowia pulcherrima, Candida zemplinina), a reproducible PCR method was devised to discriminate strains at the subspecies level. The method combines different oligonucleotides based on tandem repeats with a second oligonucleotide based on a conserved tRNA region, specific for ascomycetes. Tandem repeats are randomly dispersed in all eukaryotic genomes and tRNA genes are conserved and present in several copies in different chromosomes. As an example, the method was applied to discriminate native M. pulcherrima strains but it could be extended to differentiate strains from other non-Saccharomyces species. The biodiversity of species and strains found in the grape ecosystem is a potential source of new enzymes, fungicides and/or novel sustainable methods for biological control of phytopathogens.

  8. 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

  9. De novo genome assembly of Geosmithia morbida, the causal agent of thousand cankers disease

    PubMed Central

    Westbrook, Anthony; Woeste, Keith

    2016-01-01

    Geosmithia morbida is a filamentous ascomycete that causes thousand cankers disease in the eastern black walnut tree. This pathogen is commonly found in the western U.S.; however, recently the disease was also detected in several eastern states where the black walnut lumber industry is concentrated. G. morbida is one of two known phytopathogens within the genus Geosmithia, and it is vectored into the host tree via the walnut twig beetle. We present the first de novo draft genome of G. morbida. It is 26.5 Mbp in length and contains less than 1% repetitive elements. The genome possesses an estimated 6,273 genes, 277 of which are predicted to encode proteins with unknown functions. Approximately 31.5% of the proteins in G. morbida are homologous to proteins involved in pathogenicity, and 5.6% of the proteins contain signal peptides that indicate these proteins are secreted. Several studies have investigated the evolution of pathogenicity in pathogens of agricultural crops; forest fungal pathogens are often neglected because research efforts are focused on food crops. G. morbida is one of the few tree phytopathogens to be sequenced, assembled and annotated. The first draft genome of G. morbida serves as a valuable tool for comprehending the underlying molecular and evolutionary mechanisms behind pathogenesis within the Geosmithia genus. PMID:27168971

  10. abaA controls phialide differentiation in Aspergillus nidulans.

    PubMed Central

    Sewall, T C; Mims, C W; Timberlake, W E

    1990-01-01

    Aspergillus nidulans is an ascomycetous fungus that reproduces asexually by forming multicellular conidiophores and uninucleate spores called conidia. Loss of function mutations in the abacus A (abaA) regulatory locus result in formation of aberrant conidiophores that fail to produce conidia. Wild-type conidiophores form two tiers of sterigmata. The first tier, metulae, divide to produce the second tier, phialides. Phialides are sporogenous cells that produce conidia through a specialized apical budding process. We have examined conidiophore development in an abaA- strain at the ultrastructural level. The results showed that in the mutant metulae produce supernumerary tiers of cells with metula-like, rather than phialide-like, properties. Temperature shift experiments with an abaA14ts strain demonstrated that abaA+ function induced phialide formation by the aberrant abacus cells and was continuously required for maintenance of phialide function. In the absence of abaA+ activity, metulae simply proliferated and later developmental steps never occurred. We conclude that abaA+ directs the differentiation of phialides and is continuously required for maintenance of their function. PMID:2152124

  11. Organization of Enzymes in the Common Aromatic Synthetic Pathway: Evidence for Aggregation in Fungi

    PubMed Central

    Ahmed, S. I.; Giles, Norman H.

    1969-01-01

    Centrifugation in sucrose density gradients of partially purified extracts from six species of fungi, i.e., Rhizopus stolonifer, Phycomyces nitens, Absidia glauca (Phycomycetes), Aspergillus nidulans (Ascomycetes), Coprinus lagopus, and Ustilago maydis (Basidiomycetes), indicate that the five enzymes catalyzing steps two to six in the prechorismic acid part of the polyaromatic synthetic pathway sediment together. The sedimentation coefficients for these enzymes are very similar in the six species and are comparable to those previously observed for the multienzyme complexes (arom aggregates) of Neurospora crassa and Saccharomyces cerevisiae. These results are interpreted as indicating the presence in each of these fungi of arom aggregates, presumably encoded by arom gene clusters similar to those in N. crassa and S. cerevisiae. Evidence has also been obtained for the presence in two species (A. nidulans and U. maydis) and the absence in the other four species of a second dehydroquinase isozyme which is distinguishable from the synthetic activity on the basis of both thermostability tests and S values. This second dehydroquinase, which is apparently involved in the catabolism of quinic acid via a pathway similar to that in N. crassa, is inducible in A. nidulans (as it is in N. crassa), but constitutive in U. maydis. These comparative findings are discussed in relation to the organization, evolution, and possible functional relationships of synthetic and catabolic aromatic pathways in fungi. PMID:5802608

  12. Conflicting results obtained by RAPD-PCR and large-subunit rDNA sequences in determining and comparing yeast strains isolated from flowers: a comparison of two methods.

    PubMed

    Herzberg, Michael; Fischer, Reinhard; Titze, Andreas

    2002-07-01

    Sixty-six yeast strains isolated from the nectar of various plant species in Central Europe were characterized by randomly amplified polymorphic DNA PCR (RAPD-PCR) and by sequencing of the variable D1/D2 domain of large-subunit (26S) rDNA. The usefulness of both methods for the determination and comparison of unknown ascomycetous and basidiomycetous yeast strains was compared and evaluated. The reproducibility of RAPD-PCR was shown to be low and the information obtained by this method was clearly not as precise as that obtained from sequence analysis. Numerous imponderables make RAPD-PCR analysis unreliable, at least as a means of identifying yeasts in ecological studies. The lack of standard protocols for RAPD-PCR analysis and the absence of a general database of banding patterns made it impossible to identify unknown yeast strains or to recognize new species. In contrast to RAPD-PCR, sequence analysis of the D1/D2 domain was found to be a fast and reliable method for the rapid identification of yeast species and was also shown to be an invaluable tool for the discovery of new species.

  13. Significant and persistent impact of timber harvesting on soil microbial communities in Northern coniferous forests.

    PubMed

    Hartmann, Martin; Howes, Charles G; VanInsberghe, David; Yu, Hang; Bachar, Dipankar; Christen, Richard; Henrik Nilsson, Rolf; Hallam, Steven J; Mohn, William W

    2012-12-01

    Forest ecosystems have integral roles in climate stability, biodiversity and economic development. Soil stewardship is essential for sustainable forest management. Organic matter (OM) removal and soil compaction are key disturbances associated with forest harvesting, but their impacts on forest ecosystems are not well understood. Because microbiological processes regulate soil ecology and biogeochemistry, microbial community structure might serve as indicator of forest ecosystem status, revealing changes in nutrient and energy flow patterns before they have irreversible effects on long-term soil productivity. We applied massively parallel pyrosequencing of over 4.6 million ribosomal marker sequences to assess the impact of OM removal and soil compaction on bacterial and fungal communities in a field experiment replicated at six forest sites in British Columbia, Canada. More than a decade after harvesting, diversity and structure of soil bacterial and fungal communities remained significantly altered by harvesting disturbances, with individual taxonomic groups responding differentially to varied levels of the disturbances. Plant symbionts, like ectomycorrhizal fungi, and saprobic taxa, such as ascomycetes and actinomycetes, were among the most sensitive to harvesting disturbances. Given their significant ecological roles in forest development, the fate of these taxa might be critical for sustainability of forest ecosystems. Although abundant bacterial populations were ubiquitous, abundant fungal populations often revealed a patchy distribution, consistent with their higher sensitivity to the examined soil disturbances. These results establish a comprehensive inventory of bacterial and fungal community composition in northern coniferous forests and demonstrate the long-term response of their structure to key disturbances associated with forest harvesting.

  14. Fungal secretomes--nature's toolbox for white biotechnology.

    PubMed

    Bouws, Henning; Wattenberg, Andreas; Zorn, Holger

    2008-09-01

    Adapting their metabolism to varying carbon and nitrogen sources, saprophytic fungi produce an arsenal of extracellular enzymes, the secretome, which allows for an efficient degradation of lignocelluloses and further biopolymers. Based on fundamental advances in electrophoretic, chromatographic, and mass spectrometric techniques on the one hand and the availability of annotated fungal genomes and sophisticated bioinformatic software tools on the other hand, a detailed analysis of fungal secretomes has become feasible. While a number of reports on ascomycetous secretomes of, e.g., Aspergillus, Trichoderma, and Fusarium species are already available, studies on basidiomycetes have been mainly focused on the two model organisms Phanerochaete chrysosporium and Coprinopsis cinerea so far. Though an impressive number and diversity of fungal biocatalysts has been revealed by secretome analyses, the identity and function of many extracellular proteins still remains to be elucidated. A comprehensive understanding of the qualitative and quantitative composition of fungal secretomes, together with their synergistic actions and kinetic expression profiles, will allow for the development of optimized enzyme cocktails for white biotechnology.

  15. Identification of medically relevant species of arthroconidial yeasts by use of matrix-assisted laser desorption ionization-time of flight mass spectrometry.

    PubMed

    Kolecka, Anna; Khayhan, Kantarawee; Groenewald, Marizeth; Theelen, Bart; Arabatzis, Michael; Velegraki, Aristea; Kostrzewa, Markus; Mares, Mihai; Taj-Aldeen, Saad J; Boekhout, Teun

    2013-08-01

    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.

  16. α1-Tubulin FaTuA1 plays crucial roles in vegetative growth and conidiation in Fusarium asiaticum.

    PubMed

    Hu, Weiqun; Zhang, Xiaoping; Chen, Xiang; Zheng, Jingwu; Yin, Yanni; Ma, Zhonghua

    2015-04-01

    The filamentous ascomycete Fusarium asiaticum contains two homologous genes FaTUA1 and FaTUA2 encoding α-tubulins. In this study, we found that FaTUA2 was dispensable for vegetative growth and sporulation in F. asiaticum. The deletion of FaTUA1 however led to dramatically reduced mycelial growth, twisted hyphae and abnormal nuclei in apical cells of hyphae. The FaTUA1 deletion mutant (ΔFaTuA1-5) also showed a significant decrease in conidiation, and produced abnormal conidia. Pathogenicity assays showed that ΔFaTuA1-5 exhibited decreased virulence on wheat head. Unexpectedly, the deletion of FaTUA1 led to resistance to high temperatures. In addition, ΔFaTuA2 showed increased sensitivity to carbendazim. Furthermore, increased FaTUA2 expression in ΔFaTuA1-5 partially restored the defects of the mutant in mycelial growth, conidial production and virulence, vice versa, increased FaTUA1 expression in the FaTUA2 deletion mutant also partially relieved the defect of the mutant in the delay of conidial germination. Taken together, these results indicate that FaTuA1 plays crucial roles in vegetative growth and development, and the functions of FaTuA1 and FaTuA2 are partially interchangeable in F. asiaticum.

  17. Insights into natural products biosynthesis from analysis of 490 polyketide synthases from Fusarium.

    PubMed

    Brown, Daren W; Proctor, Robert H

    2016-04-01

    Species of the fungus Fusarium collectively cause disease on almost all crop plants and produce numerous natural products (NPs), including some of the mycotoxins of greatest concern to agriculture. Many Fusarium NPs are derived from polyketide synthases (PKSs), large multi-domain enzymes that catalyze sequential condensation of simple carboxylic acids to form polyketides. To gain insight into the biosynthesis of polyketide-derived NPs in Fusarium, we retrieved 488 PKS gene sequences from genome sequences of 31 species of the fungus. In addition to these apparently functional PKS genes, the genomes collectively included 81 pseudogenized PKS genes. Phylogenetic analysis resolved the PKS genes into 67 clades, and based on multiple lines of evidence, we propose that homologs in each clade are responsible for synthesis of a polyketide that is distinct from those synthesized by PKSs in other clades. The presence and absence of PKS genes among the species examined indicated marked differences in distribution of PKS homologs. Comparisons of Fusarium PKS genes and genes flanking them to those from other Ascomycetes provided evidence that Fusarium has the genetic potential to synthesize multiple NPs that are the same or similar to those reported in other fungi, but that have not yet been reported in Fusarium. The results also highlight ways in which such analyses can help guide identification of novel Fusarium NPs and differences in NP biosynthetic capabilities that exist among fungi.

  18. An isoprenylation and palmitoylation motif promotes intraluminal vesicle delivery of proteins in cells from distant species.

    PubMed

    Oeste, Clara L; Pinar, Mario; Schink, Kay O; Martínez-Turrión, Javier; Stenmark, Harald; Peñalva, 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.

  19. Bioprospection of cold-adapted yeasts with biotechnological potential from Antarctica.

    PubMed

    Martorell, María Martha; Ruberto, Lucas Adolfo Mauro; Fernández, Pablo Marcelo; Castellanos de Figueroa, Lucía Inés; Mac Cormack, Walter Patricio

    2017-03-08

    The aim of this study was to investigate the ability to produce extracellular hydrolytic enzymes at low temperature of yeasts isolated from 25 de Mayo island, Antarctica, and to identify those exhibiting one or more of the evaluated enzymatic activities. A total of 105 yeast isolates were obtained from different samples and 66 were identified. They belonged to 12 basidiomycetous and four ascomycetous genera. Most of the isolates were ascribed to the genera Cryptococcus, Mrakia, Cystobasidium, Rhodotorula, Gueomyces, Phenoliferia, Leucosporidium, and Pichia. Results from enzymes production at low temperatures revealed that the Antarctic environment contains metabolically diverse cultivable yeasts, which represent potential tools for biotechnological applications. While most the isolates proved to produce 2-4 of the investigated exoenzymes, two of them evidenced the six evaluated enzymatic activities: Pichia caribbica and Guehomyces pullulans, which were characterized as psycrotolerant and psycrophilic, respectively. In addition, P. caribbica could assimilate several n-alkanes and diesel fuel. The enzyme production profile and hydrocarbons assimilation capacity, combined with its high level of biomass production and the extended exponential growth phase make P. caribbica a promising tool for cold environments biotechnological purposes in the field of cold-enzymes production and oil spills bioremediation as well.

  20. Molecular approach to characterize ectomycorrhizae fungi from Mediterranean pine stands in Portugal.

    PubMed

    Ragonezi, Carla; Caldeira, A Teresa; Martins, M Rosário; Salvador, Cátia; Santos-Silva, Celeste; Ganhão, 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.

  1. Deletion of a Yci1 Domain Protein of Candida albicans Allows Homothallic Mating in MTL Heterozygous Cells

    PubMed Central

    Sun, Yuan; Gadoury, Christine; Hirakawa, Matthew P.; Bennett, Richard J.; Harcus, Doreen; Marcil, Anne

    2016-01-01

    ABSTRACT It has been proposed that the ancestral fungus was mating competent and homothallic. However, many mating-competent fungi were initially classified as asexual because their mating capacity was hidden behind layers of regulation. For efficient in vitro mating, the essentially obligate diploid ascomycete pathogen Candida albicans has to change its mating type locus from heterozygous MTLa/α to homozygous MTLa/a or MTLα/α and then undergo an environmentally controlled epigenetic switch to the mating-competent opaque form. These requirements greatly reduce the potential for C. albicans mating. Deletion of the Yci1 domain gene OFR1 bypasses the need for C. albicans cells to change the mating type locus from heterozygous to homozygous prior to switching to the opaque form and mating and allows homothallic mating of MTL heterozygous strains. This bypass is carbon source dependent and does not occur when cells are grown on glucose. Transcriptional profiling of ofr1 mutant cells shows that in addition to regulating cell type and mating circuitry, Ofr1 is needed for proper regulation of histone and chitin biosynthesis gene expression. It appears that OFR1 is a key regulator in C. albicans and functions in part to maintain the cryptic mating phenotype of the pathogen. PMID:27118591

  2. Reference genes for quantitative real-time PCR analysis in symbiont Entomomyces delphacidicola of Nilaparvata lugens (Stål)

    PubMed Central

    Wan, Pin-Jun; Tang, Yao-Hua; Yuan, San-Yue; He, Jia-Chun; Wang, Wei-Xia; Lai, Feng-Xiang; Fu, Qiang

    2017-01-01

    Nilaparvata lugens (Stål) (Hemiptera: Delphacidae) is a major rice pest that harbors an endosymbiont ascomycete fungus, Entomomyces delphacidicola str. NLU (also known as yeast-like symbiont, YLS). Driving by demand of novel population management tactics (e.g. RNAi), the importance of YLS has been studied and revealed, which greatly boosts the interest of molecular level studies related to YLS. The current study focuses on reference genes for RT-qPCR studies related to YLS. Eight previously unreported YLS genes were cloned, and their expressions were evaluated for N. lugens samples of different developmental stages and sexes, and under different nutritional conditions and temperatures. Expression stabilities were analyzed by BestKeeper, geNorm, NormFinder, ΔCt method and RefFinder. Furthermore, the selected reference genes for RT-qPCR of YLS genes were validated using targeted YLS genes that respond to different nutritional conditions (amino acid deprivation) and RNAi. The results suggest that ylsRPS15p/ylsACT are the most suitable reference genes for temporal gene expression profiling, while ylsTUB/ylsACT and ylsRPS15e/ylsGADPH are the most suitable reference gene choices for evaluating nutrition and temperature effects. Validation studies demonstrated the advantage of using endogenous YLS reference genes for YLS studies. PMID:28198810

  3. Ericoid mycorrhizal root fungi and their multicopper oxidases from a temperate forest shrub

    PubMed Central

    Wurzburger, Nina; Higgins, Brian P; Hendrick, Ronald L

    2012-01-01

    Ericoid mycorrhizal fungi (ERM) may specialize in capturing nutrients from their host's litter as a strategy for regulating nutrient cycles in terrestrial ecosystems. In spite of their potential significance, we know little about the structure of ERM fungal communities and the genetic basis of their saprotrophic traits (e.g., genes encoding extracellular enzymes). Rhododendron maximum is a model ERM understory shrub that influences the nutrient cycles of montane hardwood forests in the southern Appalachians (North Carolina, USA). We sampled ERM roots of R. maximum from organic and mineral soil horizons and identified root fungi by amplifying and sequencing internal transcribed spacer (ITS) ribosomal DNA (rDNA) collected from cultures and clones. We observed 71 fungal taxa on ERM roots, including known symbionts Rhizoscyphus ericae and Oidiodendron maius, putative symbionts from the Helotiales, Chaetothyriales, and Sebacinales, ectomycorrhizal symbionts, and saprotrophs. Supporting the idea that ERM fungi are adept saprotrophs, richness of root-fungi was greater in organic than in mineral soil horizons. To study the genetic diversity of oxidative enzymes that contribute to decomposition, we amplified and sequenced a portion of genes encoding multicopper oxidases (MCOs) from ERM ascomycetes. Most fungi possessed multiple copies of MCO sequences with strong similarities to known ferroxidases and laccases. Our findings indicate that R. maximum associates with a taxonomically and ecologically diverse fungal community. The study of MCO gene diversity and expression may be useful for understanding how ERM root fungi regulate the cycling of nutrients between the host plant and the soil environment. PMID:22408727

  4. 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

  5. 13C pulse-labeling assessment of the community structure of active fungi in the rhizosphere of a genetically starch-modified potato (Solanum tuberosum) cultivar and its parental isoline.

    PubMed

    Hannula, S E; Boschker, H T S; de Boer, W; van Veen, J A

    2012-05-01

    • The aim of this study was to gain understanding of the carbon flow from the roots of a genetically modified (GM) amylopectin-accumulating potato (Solanum tuberosum) cultivar and its parental isoline to the soil fungal community using stable isotope probing (SIP). • The microbes receiving (13)C from the plant were assessed through RNA/phospholipid fatty acid analysis with stable isotope probing (PLFA-SIP) at three time-points (1, 5 and 12 d after the start of labeling). The communities of Ascomycota, Basidiomycota and Glomeromycota were analysed separately with RT-qPCR and terminal restriction fragment length polymorphism (T-RFLP). • Ascomycetes and glomeromycetes received carbon from the plant as early as 1 and 5 d after labeling, while basidiomycetes were slower in accumulating the labeled carbon. The rate of carbon allocation in the GM variety differed from that in its parental variety, thereby affecting soil fungal communities. • We conclude that both saprotrophic and mycorrhizal fungi rapidly metabolize organic substrates flowing from the root into the rhizosphere, that there are large differences in utilization of root-derived compounds at a lower phylogenetic level within investigated fungal phyla, and that active communities in the rhizosphere differ between the GM plant and its parental cultivar through effects of differential carbon flow from the plant.

  6. Seasonal Dynamics of Arbuscular Mycorrhizal Fungal Communities in Roots in a Seminatural Grassland▿ †

    PubMed Central

    Santos-González, Juan C.; Finlay, Roger D.; Tehler, Anders

    2007-01-01

    Symbiotic arbuscular mycorrhizal fungi (AMF) have been shown to influence both the diversity and productivity of grassland plant communities. These effects have been postulated to depend on the differential effects of individual mycorrhizal taxa on different plant species; however, so far there are few detailed studies of the dynamics of AMF colonization of different plant species. In this study, we characterized the communities of AMF colonizing the roots of two plant species, Prunella vulgaris and Antennaria dioica, in a Swedish seminatural grassland at different times of the year. The AMF small subunit rRNA genes were subjected to PCR, cloning, sequencing, and phylogenetic analysis. Nineteen discrete sequence types belonging to Glomus groups A and B and to the genus Acaulospora were distinguished. No significant seasonal changes in the species compositions of the AMF communities as a whole were observed. However, the two plant species hosted significantly different AMF communities. P. vulgaris hosted a rich AMF community throughout the entire growing season. The presence of AMF in A. dioica decreased dramatically in autumn, while an increased presence of Ascomycetes species was detected. PMID:17630308

  7. Description of Komagataella phaffii sp. nov. and the transfer of Pichia pseudopastoris to the methylotrophic yeast genus Komagataella.

    PubMed

    Kurtzman, Cletus P

    2005-03-01

    The new methanol-assimilating yeast species Komagataella phaffii Kurtzman sp. nov. (type strain NRRL Y-7556(T)=CBS 2612(T)) is described. Of the four known strains of this species, two were isolated from black oak trees in California, USA, one from an Emory oak in Arizona, USA, and one from an unidentified source in Mexico. The species forms hat-shaped ascospores in deliquescent asci and appears to be homothallic. Analysis of nucleotide sequences from domains D1/D2 of large-subunit (26S) rDNA separates the new species from Komagataella pastoris, the type species of the genus, and from Pichia pseudopastoris, which is here renamed Komagataella pseudopastoris (Dlauchy, Tornai-Lehoczki, Fulop & Peter) Kurtzman comb. nov. (type strain NRRL Y-27603(T)=CBS 9187(T)=NCAIM Y 01541(T)). On the basis of D1/D2 26S rDNA sequence analysis, the three species now assigned to the genus Komagataella represent a clade that is phylogenetically isolated from other ascomycetous yeast genera.

  8. Molecular phylogenetic analysis reveals the new genus Hemisphaericaspora of the family Debaryomycetaceae.

    PubMed

    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.

  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. Three new genera representing novel lineages of Sordariomycetidae (Sordariomycetes, Ascomycota) from tropical freshwater habitats in Costa Rica.

    PubMed

    Ferrer, Astrid; Miller, Andrew N; Sarmiento, Carolina; Shearer, Carol A

    2012-01-01

    Three new genera are established in the Sordariomycetidae based on morphological and molecular data (SSU and LSU nrDNA) to accommodate five ascomycete species collected from submerged woody debris in freshwater habitats from Costa Rica. The genus Bullimyces contains three new species, B. communis, B. costaricensis and B. aurisporus. Bullimyces is characterized by globose to subglobose, membranous, black, ostiolate ascomata; deliquescent, hyaline, globose cells that fill the center of the centrum; unitunicate asci that deliquesce early in some species; and septate, thick-walled ascospores with or without gelatinous sheaths or appendages. Bullimyces species form a well supported clade with 100% bootstrap support, but the position of the genus in the Sordariomycetidae remains unclear. The second genus, Riomyces, is represented by a single species, R. rotundus. Riomyces is characterized by globose to subglobose, membranous, black, ostiolate ascomata, unitunicate, cylindrical asci, hyaline, globose cells that fill the hamathecium and septate, thick-walled ascospores with a gelatinous sheath. Although Riomyces is morphologically similar to Bullimyces, the two genera did not group together with support in any analysis. The third genus, Hydromelitis, is represented by a single species, H. pulchella. Hydromelitis is characterized by pyriform, membranous, black, ostiolate ascomata, unitunicate asci lacking an apical structure, simple, thin-walled, septate paraphyses and hyaline to golden yellow, multiseptate, thick-walled ascospores with a gelatinous sheath. Bullimyces, Riomyces and Hydromelitis were nested within an unsupported clade consisting of members of the Ophiostomatales, Magnaporthales and freshwater Annulatacaceae sensu lato and sensu stricto.

  11. A natural O-ring optimizes the dispersal of fungal spores

    PubMed Central

    Fritz, Joerg A.; Seminara, Agnese; Roper, Marcus; Pringle, Anne; Brenner, Michael P.

    2013-01-01

    The forcibly ejected spores of ascomycete fungi must penetrate several millimetres of nearly still air surrounding sporocarps to reach dispersive airflows, and escape is facilitated when a spore is launched with large velocity. To launch, the spores of thousands of species are ejected through an apical ring, a small elastic pore. The startling diversity of apical ring and spore shapes and dimensions make them favoured characters for both species descriptions and the subsequent inference of relationships among species. However, the physical constraints shaping this diversity and the adaptive benefits of specific morphologies are not understood. Here, we develop an elastohydrodynamic theory of the spore's ejection through the apical ring and demonstrate that to avoid enormous energy losses during spore ejection, the four principal morphological dimensions of spore and apical ring must cluster within a nonlinear one-dimensional subspace. We test this prediction using morphological data for 45 fungal species from two different classes and 18 families. Our sampling encompasses multiple loss and gain events and potentially independent origins of this spore ejection mechanism. Although the individual dimensions of the spore and apical ring are only weakly correlated with each other, they collapse into the predicted subspace with high accuracy. The launch velocity appears to be within 2 per cent of the optimum for over 90 per cent of all forcibly ejected species. Although the morphological diversity of apical rings and spores appears startlingly diverse, a simple principle can be used to organize it. PMID:23782534

  12. HapX Mediates Iron Homeostasis in the Pathogenic Dermatophyte Arthroderma benhamiae but Is Dispensable for Virulence

    PubMed Central

    Kröber, Antje; Scherlach, Kirstin; Hortschansky, Peter; Shelest, Ekaterina; Staib, Peter; Kniemeyer, Olaf; Brakhage, Axel A.

    2016-01-01

    For many pathogenic fungi, siderophore-mediated iron acquisition is essential for virulence. The process of siderophore production and further mechanisms to adapt to iron limitation are strictly controlled in fungi to maintain iron homeostasis. Here we demonstrate that the human pathogenic dermatophyte Arthroderma benhamiae produces the hydroxamate siderophores ferricrocin and ferrichrome C. Additionally, we show that the iron regulator HapX is crucial for the adaptation to iron starvation and iron excess, but is dispensable for virulence of A. benhamiae. Deletion of hapX caused downregulation of siderophore biosynthesis genes leading to a decreased production of siderophores during iron starvation. Furthermore, HapX was required for transcriptional repression of genes involved in iron-dependent pathways during iron-depleted conditions. Additionally, the ΔhapX mutant of A. benhamiae was sensitive to high-iron concentrations indicating that HapX also contributes to iron detoxification. In contrast to other pathogenic fungi, HapX of A. benhamiae was redundant for virulence and a ΔhapX mutant was still able to infect keratinized host tissues in vitro. Our findings underline the highly conserved role of the transcription factor HapX for maintaining iron homeostasis in ascomycetous fungi but, unlike in many other human and plant pathogenic fungi, HapX of A. benhamiae is not a virulence determinant. PMID:26960149

  13. Mdm31 protein mediates sensitivity to potassium ionophores but does not regulate mitochondrial morphology or phospholipid trafficking in Schizosaccharomyces pombe.

    PubMed

    Ivan, Branislav; Lajdova, Dana; Abelovska, Lenka; Balazova, Maria; Nosek, Jozef; Tomaska, Lubomir

    2015-03-01

    Mdm31p is an inner mitochondrial membrane (IMM) protein with unknown function in Saccharomyces cerevisiae. Mutants lacking Mdm31p contain only a few giant spherical mitochondria with disorganized internal structure, altered phospholipid composition and disturbed ion homeostasis, accompanied by increased resistance to the electroneutral K+ /H+ ionophore nigericin. These phenotypes are interpreted as resulting from diverse roles of Mdm31p, presumably in linking mitochondrial DNA (mtDNA) to the machinery involved in segregation of mitochondria, in mediating cation transport across IMM and in phospholipid shuttling between mitochondrial membranes. To investigate which of the roles of Mdm31p are conserved in ascomycetous yeasts, we analysed the Mdm31p orthologue in Schizosaccharomyces pombe. Our results demonstrate that, similarly to its S. cerevisiae counterpart, SpMdm31 is a mitochondrial protein and its absence results in increased resistance to nigericin. However, in contrast to S. cerevisiae, Sz. pombe cells lacking SpMdm31 are also less sensitive to the electrogenic K+ ionophore valinomycin. Moreover, mitochondria of the fission yeast mdm31Δ mutant display no changes in morphology or phospholipid composition. Therefore, in terms of function, the two orthologous proteins appear to have considerably diverged between these two evolutionarily distant yeast species, possibly sharing only their participation in ion homeostasis.

  14. Evolution of complex symbiotic relationships in a morphologically derived family of lichen-forming fungi.

    PubMed

    Divakar, Pradeep K; Crespo, Ana; Wedin, Mats; Leavitt, Steven D; Hawksworth, David L; Myllys, Leena; McCune, Bruce; Randlane, Tiina; Bjerke, Jarle W; Ohmura, Yoshihito; Schmitt, Imke; Boluda, Carlos G; Alors, David; Roca-Valiente, Beatriz; Del-Prado, Ruth; Ruibal, Constantino; Buaruang, Kawinnat; Núñez-Zapata, Jano; Amo de Paz, Guillermo; Rico, Víctor J; Molina, M Carmen; Elix, John A; Esslinger, Theodore L; Tronstad, Inger Kristin K; Lindgren, Hanna; Ertz, Damien; Gueidan, Cécile; Saag, Lauri; Mark, Kristiina; Singh, Garima; Dal Grande, Francesco; Parnmen, Sittiporn; Beck, Andreas; Benatti, Michel Navarro; Blanchon, Dan; Candan, Mehmet; Clerc, Philippe; Goward, Trevor; Grube, Martin; Hodkinson, Brendan P; Hur, Jae-Seoun; Kantvilas, Gintaras; Kirika, Paul M; Lendemer, James; Mattsson, Jan-Eric; Messuti, María Inés; Miadlikowska, Jolanta; Nelsen, Matthew; Ohlson, Jan I; Pérez-Ortega, Sergio; Saag, Andres; Sipman, Harrie J M; Sohrabi, Mohammad; Thell, Arne; Thor, Göran; Truong, Camille; Yahr, Rebecca; Upreti, Dalip K; Cubas, Paloma; Lumbsch, H Thorsten

    2015-12-01

    We studied the evolutionary history of the Parmeliaceae (Lecanoromycetes, Ascomycota), one of the largest families of lichen-forming fungi with complex and variable morphologies, also including several lichenicolous fungi. We assembled a six-locus data set including nuclear, mitochondrial and low-copy protein-coding genes from 293 operational taxonomic units (OTUs). The lichenicolous lifestyle originated independently three times in lichenized ancestors within Parmeliaceae, and a new generic name is introduced for one of these fungi. In all cases, the independent origins occurred c. 24 million yr ago. Further, we show that the Paleocene, Eocene and Oligocene were key periods when diversification of major lineages within Parmeliaceae occurred, with subsequent radiations occurring primarily during the Oligocene and Miocene. Our phylogenetic hypothesis supports the independent origin of lichenicolous fungi associated with climatic shifts at the Oligocene-Miocene boundary. Moreover, diversification bursts at different times may be crucial factors driving the diversification of Parmeliaceae. Additionally, our study provides novel insight into evolutionary relationships in this large and diverse family of lichen-forming ascomycetes.

  15. Biosynthesis and accumulation of ergoline alkaloids in a mutualistic association between Ipomoea asarifolia (Convolvulaceae) and a clavicipitalean fungus.

    PubMed

    Markert, Anne; Steffan, Nicola; Ploss, Kerstin; Hellwig, Sabine; Steiner, Ulrike; Drewke, Christel; Li, Shu-Ming; Boland, Wilhelm; Leistner, Eckhard

    2008-05-01

    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.

  16. Characterization of the cell wall of the ubiquitous plant pathogen Botrytis cinerea.

    PubMed

    Cantu, Dario; Greve, L Carl; Labavitch, John M; Powell, Ann L T

    2009-12-01

    The ascomycete Botrytis cinerea is a destructive and ubiquitous plant pathogen and represents a model organism for the study of necrotrophic fungal pathogens. Higher fungi possess a complex and dynamic multilayer cell wall involved in crucial aspects of fungal development, growth and pathogenicity. Plant resistance to microbial pathogens is determined often by the capacity of the plant to recognize molecular patterns associated with the surface of an interacting microbe. Here we report the chemical characterization of cell walls from B. cinerea during axenic growth. Neutral sugars and proteins constituted most of the mass of the B. cinerea cell walls, although chitin and uronic acids were detected. Glucose was the most abundant neutral sugar, but arabinose, galactose, xylose and mannose also were present. Changes in cell wall composition during culture were observed. As the culture developed, protein levels declined, while chitin and neutral sugars increased. Growth of B. cinerea was associated with a remarkable decline in the fraction of its cell wall material that was soluble in hot alkali. These results suggest that the cell wall of B. cinerea undergoes significant modifications during growth, possibly becoming more extensively covalently cross-linked, as a result of aging of mycelia or in response to decreasing nutrient supply or as a consequence of increasing culture density.

  17. A dehydration-inducible gene in the truffle Tuber borchii identifies a novel group of dehydrins

    PubMed Central

    Abba', Simona; Ghignone, Stefano; Bonfante, Paola

    2006-01-01

    Background The expressed sequence tag M6G10 was originally isolated from a screening for differentially expressed transcripts during the reproductive stage of the white truffle Tuber borchii. mRNA levels for M6G10 increased dramatically during fruiting body maturation compared to the vegetative mycelial stage. Results Bioinformatics tools, phylogenetic analysis and expression studies were used to support the hypothesis that this sequence, named TbDHN1, is the first dehydrin (DHN)-like coding gene isolated in fungi. Homologs of this gene, all defined as "coding for hypothetical proteins" in public databases, were exclusively found in ascomycetous fungi and in plants. Although complete (or almost complete) fungal genomes and EST collections of some Basidiomycota and Glomeromycota are already available, DHN-like proteins appear to be represented only in Ascomycota. A new and previously uncharacterized conserved signature pattern was identified and proposed to Uniprot database as the main distinguishing feature of this new group of DHNs. Expression studies provide experimental evidence of a transcript induction of TbDHN1 during cellular dehydration. Conclusion Expression pattern and sequence similarities to known plant DHNs indicate that TbDHN1 is the first characterized DHN-like protein in fungi. The high similarity of TbDHN1 with homolog coding sequences implies the existence of a novel fungal/plant group of LEA Class II proteins characterized by a previously undescribed signature pattern. PMID:16512918

  18. Friend or foe? Biological and ecological traits of the European ash dieback pathogen Hymenoscyphus fraxineus in its native environment

    NASA Astrophysics Data System (ADS)

    Cleary, Michelle; Nguyen, Diem; Marčiulynienė, Diana; Berlin, Anna; Vasaitis, Rimvys; Stenlid, Jan

    2016-02-01

    Hymenoscyphus fraxineus, an introduced ascomycete fungus and primary causal agent of European ash dieback, was investigated on Fraxinus mandshurica trees in its native range in Primorye region of Far East Russia. This evidence is the first report of H. fraxineus on healthy, asymptomatic F. mandshurica trees. High-throughput sequencing revealed 49 distinct fungal taxa associated with leaves of F. mandshurica, 12 of which were identified to species level. Phyllosphere fungal assemblages were similar among sites despite being largely geographically distant. Many organisms comprising the foliar fungal community on F. mandshurica in Far East Russia have similarity to those reported inhabiting F. excelsior in Europe based on previous studies. However, Mycosphaerella sp., the most dominant species in this study and detected in nearly all samples, was associated only with F. mandshurica. Genetic diversity of H. fraxineus was significantly higher in the Far East Russian population than in Europe. In contrast to its aggressive behaviour on Fraxinus excelsior in Europe, H. fraxineus appears to be a benign associate of indigenous F. mandshurica that initially induces quiescent and asymptomatic infections in healthy trees prior to active host colonization normally associated with modification of host tissue during senescence.

  19. Black fungi: clinical and pathogenic approaches.

    PubMed

    De Hoog, G S; Queiroz-Telles, F; Haase, G; Fernandez-Zeppenfeldt, G; Attili Angelis, D; Gerrits Van Den Ende, A H; Matos, T; Peltroche-Llacsahuanga, H; Pizzirani-Kleiner, A A; Rainer, J; Richard-Yegres, N; Vicente, V; Yegres, F

    2000-01-01

    Data are presented on the clinically relevant black yeasts and their relatives, i.e., members of the Ascomycete order Chaetothyriales. In order to understand the pathology of these fungi it is essential to know their natural ecological niche. From a relatively low degree of molecular variability of the black yeast Exophiala dermatitidis, potential agent of brain infections in patients from East Asia, it is concluded that this species is an emerging pathogen, currently going through a process of active speciation. It is found to be an oligotrophic fungus in hot, moist environments, such as steambaths. Cladophialophora-, Fonsecaea- and Ramichloridium-like strains, known in humans as agents of chromoblastomycosis, are frequently found on rotten plant material, but the fungal molecular diversity in the environment is much higher than that on the human patient, so that it is difficult to trace the etiological agents of the disease with precision. This approach has been successful with Cladophialophora carrionii, of which cells resembling muriform cells, the tissue form of chromoblastomycosis, were found to occur in drying spines of cacti. Phagocytosis assays provide a method to distinguish between pathogens and non-pathogens, as the killing rates of strict saprobes proved to be consistently higher than of those species frequently known as agents of disease. The therapeutic possibilities for patients with chromoblastomycosis are reviewed.

  20. 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.