Publications by authors named "Keith A Seifert"

A new species of the yeast genus Blastobotrys was discovered during a worldwide survey of culturable xerophilic fungi in house dust. Several culture-dependent and independent studies from around the world detected the same species from a wide range of substrates including indoor air, cave wall paintings, bats, mummies, and the iconic self-portrait of Leonardo da Vinci from ca 1512. However, none of these studies identified their strains, clones, or OTUs as Blastobotrys.

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This study was conducted to elucidate evolutionary relationships and species diversity within the species complex (FBSC). We also evaluate the potential of these species to produce mycotoxins and other bioactive secondary metabolites. Maximum likelihood and maximum parsimony analyses of sequences from portions of four marker loci (ITS rDNA, , and ) and the combined 4495 bp data set support recognition of seven genealogically exclusive species within the FBSC.

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With the change to one scientific name for fungal taxa, generic names typified by species with sexual or asexual morph types are being evaluated to determine which names represent the same genus and thus compete for use. In this paper generic names of the Agaricomycotina (Basidiomycota) were evaluated to determine synonymy based on their type. Forty-seven sets of sexually and asexually typified names were determined to be congeneric and recommendations are made for which generic name to use.

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Background: It is estimated that 20-30% of ginseng crops in Canada are lost to root rot each harvest. This disease is commonly caused by fungal infection with , previously known as Previous reports have linked the virulence of fungal disease to the production of siderophores, a class of small-molecule iron chelators. However, these siderophores have not been identified in .

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spp. occur as plant pathogens worldwide under field and storage conditions. They lead to food spoilage and also produce several classes of secondary metabolites that contaminate the food production chain.

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Fungal endophytes are sources of novel bioactive compounds but relatively few agriculturally important fruiting plants harboring endophytes have been carefully studied. Previously, we identified a griseofulvin-producing Xylaria species isolated from Vaccinium angustifolium, V. corymbosum, and Pinus strobus.

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Ginseng root is an economically valuable crop in Canada at high risk of yield loss caused by the pathogenic fungus formerly known as . While this pathogen has been well-characterized from morphological and genetic perspectives, little is known about the secondary metabolites it produces and their role in pathogenicity. We used an untargeted tandem liquid chromatography-mass spectrometry (LC-MS)-based approach paired with global natural products social molecular networking (GNPS) to compare the metabolite profiles of virulent and avirulent strains.

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The ergot disease of cereals has become increasingly important in agricultural areas of Canada since 1999. Generally, this disease is considered to be caused by , but the taxonomy of from these areas has not been well studied. The objectives of this study were (i) to determine the phylogenetic lineages (phylogenetic species) present in agricultural areas of Canada and (ii) to develop a molecular assay that can separate the lineages on crops from other lineages.

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A new species, , isolated from decaying fruit and litter of , is described and illustrated. On the natural substrate, the new species produces determinate synnemata, with a well-defined, vivid orange red to orange red cylindrical stipe, and a greyish green capitulum. Conidiophores are typically biverticillate, or sometimes have subterminal branches, with acerose phialides that produce globose to subglobose, smooth to slightly roughened conidia.

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This genome announcement includes draft genomes from including , and cf. The draft genomes of and all three important eucalyptus pathogens, are presented. The insect associate is also described.

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The end of the 20 century and the beginning of the 21 will be remembered as the golden age of molecular systematics of Fungi. The development of the Polymerase Chain Reaction (PCR), automated sequencing, and explicit algorithms for inferring phylogenetic trees transformed fungal systematics into a hypothesis-testing discipline that would go on to serve as the foundation for comparative and evolutionary genomics. Many mycologists participated in this modernization of mycology and perhaps none more than Meredith Blackwell.

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Recent DNA-based studies have shown that the built environment is surprisingly rich in fungi. These indoor fungi - whether transient visitors or more persistent residents - may hold clues to the rising levels of human allergies and other medical and building-related health problems observed globally. The taxonomic identity of these fungi is crucial in such pursuits.

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Spore samplers are widely used in pathogen surveillance but not so much for monitoring the composition of aeromycobiota. In Canada, a nationwide spore-sampling network (AeroNet) was established as a pilot project to assess fungal community composition in air and rain samples collected using three different spore samplers in the summers of 2010 and 2011. Metabarcodes of the internal transcribed spacer (ITS) were exhaustively characterized for three of the network sites, in British Columbia (BC), Québec (QC), and Prince Edward Island (PEI), to compare performance of the samplers.

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An international survey of house dust collected from eleven countries using a modified dilution-to-extinction method yielded 7904 isolates. Of these, six strains morphologically resembled the asexual morphs of and (sexual morphs ? but were phylogenetically distinct A 28S rDNA phylogeny resolved strains as a distinct clade in with families and their closest relatives. Further analyses based on the ITS rDNA region, β-tubulin, 28S rDNA, and RNA polymerase II second largest subunit confirmed the distinct status of this clade and divided strains among two consistent subclades.

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With the change to one scientific name for fungal species, numerous papers have been published with recommendations for use or protection of competing generic names in major groups of ascomycetes. Although genera in each group of fungi were carefully considered, some competing generic names were overlooked. This paper makes recommendations for additional competing genera not considered in previous papers.

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The genus Diaporthe comprises close to 800 species, with around 2000 names attributed to it and its asexual morphs previously recognized in Phomopsis. Diaporthe species are common plant associates, including saprotrophs, pathogens, and endophytes affiliated with a diverse range of hosts worldwide. In this study, an unknown Diaporthe sp.

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Ochratoxin A (OTA) is a mycotoxin produced by some Aspergillus and Penicillium species that grow on economically important agricultural crops and food products. OTA is classified as Group 2B carcinogen and is potently nephrotoxic, which is the basis for its regulation in some jurisdictions. Using high resolution mass spectroscopy, OTA and ochratoxin B (OTB) were detected in liquid culture extracts of Penicillium thymicola DAOMC 180753 isolated from Canadian cheddar cheese.

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The genomes of Armillaria fuscipes, Ceratocystiopsis minuta, Ceratocystis adiposa, Endoconidiophora laricicola, E. polonica, and Penicillium freii DAOMC 242723 are presented in this genome announcement. These six genomes are from plant pathogens and otherwise economically important fungal species.

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With the advance to one scientific name for each fungal species, the generic names in the class Sordariomycetes typified by sexual and asexual morphs are evaluated based on their type species to determine if they compete with each other for use or protection. Recommendations are made for which of the competing generic names should be used based on criteria such as priority, number of potential names changes, and frequency of use. Some recommendations for well-known genera include Arthrinium over Apiospora, Colletotrichum over Glomerella, Menispora over Zignoëlla, Microdochium over Monographella, Nigrospora over Khuskia, and Plectosphaerella over Plectosporium.

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A survey of the fynbos biome in South Africa resulted in the isolation of 61 Penicillium species from Protea repens infructescences, air, and soil samples. Fourteen of these belong to Penicillium sect. Exilicaulis and therefore we considered it an opportunity to re-evaluate the taxonomy of the section.

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We present the full genome of Phialocephala scopiformis DAOMC 229536 (Helotiales, Ascomycota), a foliar endophyte of white spruce from eastern Quebec. DAOMC 229536 produces the anti-insectan compound rugulosin, which inhibits a devastating forestry pest, the spruce budworm. This genome will enable fungal genotyping and host-endophyte evolutionary genomics in inoculated trees.

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Several Aspergillus species produce ochratoxin A (OTA) and/or fumonisins on wine and table grapes. The relevant species and their mycotoxins have been investigated in a number of wine-producing regions around the world; however, similar data have not been reported for Canadian vineyards. A multiyear survey of black Aspergilli in Niagara, ON, vineyards was conducted to determine the diversity of species present and to assess the risk of OTA and fumonisin contamination of wine grapes from this region.

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The genus Fusarium includes more than 200 species of which 73 have been isolated from human infections. Fusarium species are opportunistic human pathogens with variable aetiology. Species determination is best made with the combined phylogeny of protein-coding genes such as elongation factor (TEF1), RNA polymerase (RPB2) and the partial β-tubulin (BT2) gene.

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