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  1. A comparative genomics study of 23 Aspergillus species from section Flavi

  2. Draft Genome Sequence of the Ectomycorrhizal Ascomycete Sphaerosporella brunnea

    Sphaerosporella brunneais a pioneer ectomycorrhizal fungus with facultative saprophytic capacities. Here, we sequenced the genome ofS. brunneastrain Sb_GMNB300, which is estimated at 51.6 Mb in size with 872 assembled contigs accounting for 12,597 predicted coding genes. This genome will be useful for comparative studies of Pezizales ectomycorrhizal symbioses.
  3. Phyllosticta citricarpa and sister species of global importance to Citrus

    Several Phyllosticta species are known as pathogens of Citrus spp., and are responsible for various disease symptoms including leaf and fruit spots. One of the most important species is P. citricarpa, which causes a foliar and fruit disease called citrus black spot. The Phyllosticta species occurring on citrus can most effectively be distinguished from P. citricarpa by means of multilocus DNA sequence data. Recent studies also demonstrated P. citricarpa to be heterothallic, and reported successful mating in the laboratory. Since the domestication of citrus, different clones of P. citricarpa have escaped Asia to other continents via trade routes, with obviousmore » disease management consequences. This pathogen profile represents a comprehensive literature review of this pathogen and allied taxa associated with citrus, focusing on identification, distribution, genomics, epidemiology and disease management. This review also considers the knowledge emerging from seven genomes of Phyllosticta spp., demonstrating unknown aspects of these species, including their mating behaviour.« less
  4. Investigation of inter- and intraspecies variation through genome sequencing of Aspergillus section Nigri

    Aspergillus section Nigri comprises filamentous fungi relevant to biomedicine, bioenergy, health, and biotechnology. In order to learn more about fungal speciation, as well as potential for applications in biotechnology and biomedicine, we sequenced 23 genomes de novo, forming a full genome compendium for the section (26 species), as well as six A. niger isolates. This allowed us to quantify both inter- and intra-species genomic variation. We further predicted 17,903 CAZymes and 2,717 secondary metabolite gene clusters, which we condensed into 455 distinct families corresponding to compound classes, 49% of which are only found in single species. We performed metabolomics andmore » genetic engineering to correlate genotypes to phenotypes, as demonstrated for the metabolite aurasperone, and by heterologous transfer of citrate production to A. nidulans. Experimental and computational analyses all supported a role in speciation for secondary metabolism and regulators and allowed us to propose a three-step model for fungal speciation.« less
  5. Regulation of Yeast-to-Hyphae Transition in Yarrowia lipolytica

    Many yeasts undergo a morphological transition from yeast-to-hyphal growth in response to environmental conditions. We used forward and reverse genetic techniques to identify genes regulating this transition in Yarrowia lipolytica . We confirmed that the transcription factor Yl msn2 is required for the transition to hyphal growth and found that signaling by the histidine kinases Yl chk1 and Yl nik1 as well as the MAP kinases of the HOG pathway (Yl ssk2 , Yl pbs2 , and Yl hog1 ) regulates the transition to hyphal growth. These results suggest that Y. lipolytica transitions to hyphal growth in response to stressmore » through multiple kinase pathways. Intriguingly, we found that a repetitive portion of the genome containing telomere-like and rDNA repeats may be involved in the transition to hyphal growth, suggesting a link between this region and the general stress response.« less
  6. Draft Genome Assemblies of Five Robust Yarrowia lipolytica Strains Exhibiting High Lipid Production, Pentose Sugar Utilization, and Sugar Alcohol Secretion from Undetoxified Lignocellulosic Biomass Hydrolysates

    Screening the genetic diversity of 45 Yarrowia lipolytica strains identified five candidates with unique metabolic capability and robustness in undetoxified switchgrass hydrolysates, including superior lipid production and efficient pentose sugar utilization. Here, we report the genome sequences of these strains to study their robustness and potential to produce fuels and chemicals.
  7. Megaphylogeny resolves global patterns of mushroom evolution

    Mushroom-forming fungi (Agaricomycetes) have the greatest morphological diversity and complexity of any group of fungi. They have radiated into most niches and fulfil diverse roles in the ecosystem, including wood decomposers, pathogens or mycorrhizal mutualists. Despite the importance of mushroom-forming fungi, large-scale patterns of their evolutionary history are poorly known, in part due to the lack of a comprehensive and dated molecular phylogeny. Here, using multigene and genome-based data, we assemble a 5,284-species phylogenetic tree and infer ages and broad patterns of speciation/extinction and morphological innovation in mushroom-forming fungi. Agaricomycetes started a rapid class-wide radiation in the Jurassic, coinciding withmore » the spread of (sub)tropical coniferous forests and a warming climate. A possible mass extinction, several clade-specific adaptive radiations and morphological diversification of fruiting bodies followed during the Cretaceous and the Paleogene, convergently giving rise to the classic toadstool morphology, with a cap, stalk and gills (pileate-stipitate morphology). This morphology is associated with increased rates of lineage diversification, suggesting it represents a key innovation in the evolution of mushroom-forming fungi. The increase in mushroom diversity started during the Mesozoic-Cenozoic radiation event, an era of humid climate when terrestrial communities dominated by gymnosperms and reptiles were also expanding.« less
  8. Linking secondary metabolites to gene clusters through genome sequencing of six diverse Aspergillus species

    Significance The genus of Aspergillus holds fungi relevant to plant and human pathology, food biotechnology, enzyme production, model organisms, and a selection of extremophiles. Here we present six whole-genome sequences that represent unexplored branches of the Aspergillus genus. The comparison of these genomes with previous genomes, coupled with extensive chemical analysis, has allowed us to identify genes for toxins, antibiotics, and anticancer compounds, as well as show that Aspergillus novofumigatus is potentially as pathogenic as Aspergillus fumigatus , and has an even more diverse set of secreted bioactive compounds. The findings are of interest to industrial biotechnology and basic research,more » as well as medical and clinical research.« less
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"Haridas, Sajeet"

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