| 1. |
- Abarenkov, Kessy, et al.
(författare)
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Annotating public fungal ITS sequences from the built environment according to the MIxS-Built Environment standard – a report from a May 23-24, 2016 workshop (Gothenburg, Sweden)
- 2016
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Ingår i: MycoKeys. - : Pensoft Publishers. - 1314-4057 .- 1314-4049. ; 16, s. 1-15
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Tidskriftsartikel (refereegranskat)abstract
- Recent molecular studies have identified substantial fungal diversity in indoor environments. Fungi and fungal particles have been linked to a range of potentially unwanted effects in the built environment, including asthma, decay of building materials, and food spoilage. The study of the built mycobiome is hampered by a number of constraints, one of which is the poor state of the metadata annotation of fungal DNA sequences from the built environment in public databases. In order to enable precise interrogation of such data – for example, “retrieve all fungal sequences recovered from bathrooms” – a workshop was organized at the University of Gothenburg (May 23-24, 2016) to annotate public fungal barcode (ITS) sequences according to the MIxS-Built Environment annotation standard (http://gensc.org/mixs/). The 36 participants assembled a total of 45,488 data points from the published literature, including the addition of 8,430 instances of countries of collection from a total of 83 countries, 5,801 instances of building types, and 3,876 instances of surface-air contaminants. The results were implemented in the UNITE database for molecular identification of fungi (http://unite.ut.ee) and were shared with other online resources. Data obtained from human/animal pathogenic fungi will furthermore be verified on culture based metadata for subsequent inclusion in the ISHAM-ITS database (http://its.mycologylab.org).
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| 2. |
- Abarenkov, Kessy, et al.
(författare)
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PlutoF—a web based workbench for ecological and taxonomic research, with an online implementation for fungal ITS sequences
- 2010
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Ingår i: Evolutionary Bioinformatics. - 1176-9343. ; 6, s. 189-196
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Tidskriftsartikel (refereegranskat)abstract
- DNA sequences accumulating in the International Nucleotide Sequence Databases (INSD) form a rich source of information for taxonomic and ecological meta-analyses. However, these databases include many erroneous entries, and the data itself is poorly annotated with metadata, making it difficult to target and extract entries of interest with any degree of precision. Here we describe the web-based workbench PlutoF, which is designed to bridge the gap between the needs of contemporary research in biology and the existing software resources and databases. Built on a relational database, PlutoF allows remote-access rapid submission, retrieval, and analysis of study, specimen, and sequence data in INSD as well as for private datasets though web-based thin clients. In contrast to INSD, PlutoF supports internationally standardized terminology to allow very specific annotation and linking of interacting specimens and species. The sequence analysis module is optimized for identification and analysis of environmental ITS sequences of fungi, but it can be modified to operate on any genetic marker and group of organisms. The workbench is available at http://plutof.ut.ee.
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| 3. |
- Abarenkov, Kessy, et al.
(författare)
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The UNITE database for molecular identification and taxonomic communication of fungi and other eukaryotes: sequences, taxa and classifications reconsidered
- 2024
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Ingår i: Nucleic Acids Research. - 0305-1048 .- 1362-4962. ; 52:D1, s. D791-D797
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Tidskriftsartikel (refereegranskat)abstract
- UNITE (https://unite.ut.ee) is a web-based database and sequence management environment for molecular identification of eukaryotes. It targets the nuclear ribosomal internal transcribed spacer (ITS) region and offers nearly 10 million such sequences for reference. These are clustered into similar to 2.4M species hypotheses (SHs), each assigned a unique digital object identifier (DOI) to promote unambiguous referencing across studies. UNITE users have contributed over 600 000 third-party sequence annotations, which are shared with a range of databases and other community resources. Recent improvements facilitate the detection of cross-kingdom biological associations and the integration of undescribed groups of organisms into everyday biological pursuits. Serving as a digital twin for eukaryotic biodiversity and communities worldwide, the latest release of UNITE offers improved avenues for biodiversity discovery, precise taxonomic communication and integration of biological knowledge across platforms. Graphical Abstract
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| 4. |
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| 5. |
- Bahram, Mohammad, et al.
(författare)
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The distance decay of similarity in communities of ectomycorrhizal fungi in different ecosystems and scales
- 2013
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Ingår i: Journal of Ecology. - : Wiley. - 0022-0477 .- 1365-2745. ; 101:5, s. 1335-1344
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Tidskriftsartikel (refereegranskat)abstract
- Despite recent advances in understanding community ecology of ectomycorrhizal fungi, little is known about their spatial patterning and the underlying mechanisms driving these patterns across different ecosystems. * This meta-study aimed to elucidate the scale, rate and causes of spatial structure of ectomycorrhizal fungal communities in different ecosystems by analysing 16 and 55 sites at the local and global scales, respectively. We examined the distance decay of similarity relationship in species- and phylogenetic lineage-based communities in relation to sampling and environmental variables. * Tropical ectomycorrhizal fungal communities exhibited stronger distance-decay patterns compared to non-tropical communities. Distance from the equator and sampling area were the main determinants of the extent of distance decay in fungal communities. The rate of distance decay was negatively related to host density at the local scale. At the global scale, lineage-level community similarity decayed faster with latitude than with longitude. * Synthesis. Spatial processes play a stronger role and over a greater scale in structuring local communities of ectomycorrhizal fungi than previously anticipated, particularly in ecosystems with greater vegetation age and closer to the equator. Greater rate of distance decay occurs in ecosystems with lower host density that may stem from increasing dispersal and establishment limitation. The relatively strong latitude effect on distance decay of lineage-level community similarity suggests that climate affects large-scale spatial processes and may cause phylogenetic clustering of ectomycorrhizal fungi at the global scale.
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| 6. |
- Bidartondo, Martin, et al.
(författare)
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Preserving accuracy in GenBank
- 2008
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Ingår i: Science. ; 319:5870
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 7. |
- Hibbett, David, et al.
(författare)
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Sequence-based classification and identification of Fungi
- 2016
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Ingår i: Mycologia. - 0027-5514. ; 108:6, s. 1049-1068
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Forskningsöversikt (refereegranskat)abstract
- Fungal taxonomy and ecology have been revolutionized by the application of molecular methods and both have increasing connections to genomics and functional biology. However, data streams from traditional specimen- and culture-based systematics are not yet fully integrated with those from metagenomic and metatranscriptomic studies, which limits understanding of the taxonomic diversity and metabolic properties of fungal communities. This article reviews current resources, needs, and opportunities for sequence-based classification and identification (SBCI) in fungi as well as related efforts in prokaryotes. To realize the full potential of fungal SBCI it will be necessary to make advances in multiple areas. Improvements in sequencing methods, including long-read and single-cell technologies, will empower fungal molecular ecologists to look beyond ITS and current shotgun metagenomics approaches. Data quality and accessibility will be enhanced by attention to data and metadata standards and rigorous enforcement of policies for deposition of data and workflows. Taxonomic communities will need to develop best practices for molecular characterization in their focal clades, while also contributing to globally useful datasets including ITS. Changes to nomenclatural rules are needed to enable valid publication of sequence-based taxon descriptions. Finally, cultural shifts are necessary to promote adoption of SBCI and to accord professional credit to individuals who contribute to community resources.
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| 8. |
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| 9. |
- Kõljalg, Urmas, et al.
(författare)
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A price tag on species
- 2022
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Ingår i: Research Ideas and Outcomes_RIO. - : Pensoft Publishers. - 2367-7163. ; 8, s. 1-7
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Tidskriftsartikel (refereegranskat)abstract
- Species have intrinsic value but also partake in a long range of ecosystem services of major economic value to humans. These values have proved hard to quantify precisely, making it all too easy to dismiss them altogether. We outline the concept of the species stock market (SSM), a system to provide a unified basis for valuation of all living species. The SSM amalgamates digitized information from natural history collections, occurrence data, and molecular sequence databases to quantify our knowledge of each species from scientific, societal, and economic points of view. The conceptual trading system will necessarily be very unlike that of the regular stock market, but the looming biodiversity crisis implores us to finally put an open and transparent price tag on symbiosis, deforestation, and pollution
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| 10. |
- Kõljalg, Urmas, et al.
(författare)
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Digital identifiers for fungal species
- 2016
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 352:6290, s. 1182-1183
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Tidskriftsartikel (refereegranskat)
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| 11. |
- Kõljalg, Urmas, et al.
(författare)
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Towards a unified paradigm for sequence-based identification of fungi.
- 2013
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Ingår i: Molecular ecology. - : Wiley. - 1365-294X .- 0962-1083. ; 22:21, s. 5271-7
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Tidskriftsartikel (refereegranskat)abstract
- The nuclear ribosomal internal transcribed spacer (ITS) region is the formal fungal barcode and in most cases the marker of choice for the exploration of fungal diversity in environmental samples. Two problems are particularly acute in the pursuit of satisfactory taxonomic assignment of newly generated ITS sequences: (i) the lack of an inclusive, reliable public reference data set and (ii) the lack of means to refer to fungal species, for which no Latin name is available in a standardized stable way. Here, we report on progress in these regards through further development of the UNITE database (http://unite.ut.ee) for molecular identification of fungi. All fungal species represented by at least two ITS sequences in the international nucleotide sequence databases are now given a unique, stable name of the accession number type (e.g. Hymenoscyphus pseudoalbidus|GU586904|SH133781.05FU), and their taxonomic and ecological annotations were corrected as far as possible through a distributed, third-party annotation effort. We introduce the term 'species hypothesis' (SH) for the taxa discovered in clustering on different similarity thresholds (97-99%). An automatically or manually designated sequence is chosen to represent each such SH. These reference sequences are released (http://unite.ut.ee/repository.php) for use by the scientific community in, for example, local sequence similarity searches and in the QIIME pipeline. The system and the data will be updated automatically as the number of public fungal ITS sequences grows. We invite everybody in the position to improve the annotation or metadata associated with their particular fungal lineages of expertise to do so through the new Web-based sequence management system in UNITE.
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| 12. |
- Kõljalg, Urmas, et al.
(författare)
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UNITE: a database providing web-based methods for the molecular identification of ectomycorrhizal fungi
- 2005
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Ingår i: New Phytologist. - : Wiley. - 0028-646X .- 1469-8137. ; 166:3, s. 1063-1068
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Tidskriftsartikel (refereegranskat)abstract
- Identification of ectomycorrhizal (ECM) fungi is often achieved through comparisons of ribosomal DNA internal transcribed spacer (ITS) sequences with accessioned sequences deposited in public databases. A major problem encountered is that annotation of the sequences in these databases is not always complete or trustworthy. In order to overcome this deficiency, we report on UNITE, an open-access database. UNITE comprises well annotated fungal ITS sequences from well defined herbarium specimens that include full herbarium reference identification data, collector/source and ecological data. At present UNITE contains 758 ITS sequences from 455 species and 67 genera of ECM fungi. UNITE can be searched by taxon name, via sequence similarity using BLAST n, and via phylogenetic sequence identification using galaxie. Following implementation, galaxie performs a phylogenetic analysis of the query sequence after alignment either to pre-existing generic alignments, or to matches retrieved from a BLAST search on the UNITE data. It should be noted that the current version of UNITE is dedicated to the reliable identification of ECM fungi. The UNITE database is accessible through the URLhttp://unite.zbi.ee.
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| 13. |
- Koureas, Dimitrios, et al.
(författare)
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Unifying European Biodiversity Informatics (Bio Unify)
- 2016
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Ingår i: Research Ideas and Outcomes. - : Pensoft Publishers. - 2367-7163. ; 2:e7787, s. 1-23
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Tidskriftsartikel (refereegranskat)abstract
- In order to preserve the variety of life on Earth, we must understand it better. Biodiversity research is at a pivotal point with research projects generating data at an ever increasing rate. Structuring, aggregating, linking and processing these data in a meaningful way is a major challenge. The systematic application of information management and engineering technologies in the study of biodiversity (biodiversity informatics) help transform data to knowledge. However, concerted action is required to be taken by existing e-infrastructures to develop and adopt common standards, provisions for interoperability and avoid overlapping in functionality. This would result in the unification of the currently fragmented landscape that restricts European biodiversity research from reaching its full potential. The overarching goal of this COST Action is to coordinate existing research and capacity building efforts, through a bottom-up trans-disciplinary approach, by unifying biodiversity informatics communities across Europe in order to support the long-term vision of modelling biodiversity on earth. BioUnify will: 1. specify technical requirements, evaluate and improve models for efficient data and workflow storage, sharing and re-use, within and between different biodiversity communities; 2. mobilise taxonomic, ecological, genomic and biomonitoring data generated and curated by natural history collections, research networks and remote sensing sources in Europe; 3. leverage results of ongoing biodiversity informatics projects by identifying and developing functional synergies on individual, group and project level; 4. raise technical awareness and transfer skills between biodiversity researchers and information technologists; 5. formulate a viable roadmap for achieving the long-term goals for European biodiversity informatics, which ensures alignment with global activities and translates into efficient biodiversity policy.
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| 14. |
- Larsson, Karl-Henrik, 1948, et al.
(författare)
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High phylogenetic diversity among corticioid homobasidiomycetes
- 2004
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Ingår i: Mycological Research. - 0953-7562. ; 108:9, s. 983-1002
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Tidskriftsartikel (refereegranskat)abstract
- Homobasidiomycetes display a variety of fruit body morphologies. Examples include gilled mushrooms, coral fungi, polypores and puffballs but also species with simple crust-like basidiomata, usually called corticioid fungi. The latter group has largely been neglected in recent studies of homobasidiomycete evolution. The major goal of the present study was to explore the impact that the addition of a wide selection of species with crust-like basidiomata would have on homobasidiomycete phylogeny. Two genes, 5.8S and 28S in the nuclear rDNA repeats, were sequenced and a data set with 178 taxa analysed using neighbour-joining and maximum parsimony methods. Support for clades was evaluated by bootstrap. Basal nodes generally received weak support and branching order for major clades remained largely unresolved. Twelve major groups were recovered and corticioid fungi make up a major or important constituent in most of them. Nine groups are strongly supported but support for euagarics and polyporoid clades is poor. Phlebioid fungi were in earlier studies merged with the polyporoid clade but are here identified as a separate clade. Athelia is allied with ectomycorrhizal genera, inter alia Piloderma and Amphinema, in a separate clade forming a sister group to the boletes. We conclude that corticioid fungi hold a considerable share of the phylogenetic diversity displayed by homobasidiomycetes, and should always be considered when phylogenetic studies of larger basidiomycetes are designed.
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| 15. |
- Lindahl, Björn, et al.
(författare)
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Fungal community analysis by high-throughput sequencing of amplified markers – a user's guide
- 2013
-
Ingår i: New Phytologist. - : Wiley. - 0028-646X .- 1469-8137. ; 199:1, s. 288-299
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Forskningsöversikt (refereegranskat)abstract
- * Novel high-throughput sequencing methods outperform earlier approaches in terms of resolution and magnitude. They enable identification and relative quantification of community members and offer new insights into fungal community ecology. These methods are currently taking over as the primary tool to assess fungal communities of plant-associated endophytes, pathogens, and mycorrhizal symbionts, as well as free-living saprotrophs. * Taking advantage of the collective experience of six research groups, we here review the different stages involved in fungal community analysis, from field sampling via laboratory procedures to bioinformatics and data interpretation. We discuss potential pitfalls, alternatives, and solutions. * Highlighted topics are challenges involved in: obtaining representative DNA/RNA samples and replicates that encompass the targeted variation in community composition, selection of marker regions and primers, options for amplification and multiplexing, handling of sequencing errors, and taxonomic identification. * Without awareness of methodological biases, limitations of markers, and bioinformatics challenges, large-scale sequencing projects risk yielding artificial results and misleading conclusions.
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| 16. |
- Nilsson, R. Henrik, 1976, et al.
(författare)
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A comprehensive, automatically updated fungal ITS sequence dataset for reference-based chimera control in environmental sequencing efforts
- 2015
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Ingår i: Microbes and Environments. - 1342-6311 .- 1347-4405. ; 30:2, s. 145-150
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Tidskriftsartikel (refereegranskat)abstract
- The nuclear ribosomal internal transcribed spacer (ITS) region is the most commonly chosen genetic marker for the molecular identification of fungi in environmental sequencing and molecular ecology studies. Several analytical issues complicate such efforts, one of which is the formation of chimeric—artificially joined—DNA sequences during PCR amplification or sequence assembly. Several software tools are currently available for chimera detection, but rely to various degrees on the presence of a chimera-free reference dataset for optimal performance. However, no such dataset is available for use with the fungal ITS region. This study introduces a comprehensive, automatically updated reference dataset for fungal ITS sequences based on the UNITE database for the molecular identification of fungi. This dataset supports chimera detection throughout the fungal kingdom and for full-length ITS sequences as well as partial (ITS1 or ITS2 only) datasets. The performance of the dataset on a large set of artificial chimeras was above 99.5%, and we subsequently used the dataset to remove nearly 1,000 compromised fungal ITS sequences from public circulation. The dataset is available at http://unite.ut.ee/repository.php and is subject to web-based third-party curation.
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| 17. |
- Nilsson, R. Henrik, 1976, et al.
(författare)
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A note on the incidence of reverse complementary fungal ITS sequences in the public sequence databases and a software tool for their detection and reorientation
- 2011
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Ingår i: Mycoscience. - : The Mycological Society of Japan. - 1340-3540 .- 1618-2545. ; 52:4, s. 278-282
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Tidskriftsartikel (refereegranskat)abstract
- Reverse complementary DNA sequences––sequences that are inadvertently cast backward and in which all purines and pyrimidines are transposed––are not uncommon in sequence databases, where they may introduce noise into sequence-based research. We show that about 1% of the public fungal ITS sequences, the most commonly sequenced genetic marker in mycology, are reverse complementary, and we introduce an open source software solution to automate their detection and reorientation. The MacOSX/Linux/UNIX software operates on public or private datasets of any size, although some 50 base pairs of the 5.8S gene of the ITS region are needed for the analysis.
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| 18. |
- Nilsson, R. Henrik, 1976, et al.
(författare)
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Five simple guidelines for establishing basic authenticity and reliability of newly generated fungal ITS sequences
- 2012
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Ingår i: MycoKeys. - : Pensoft Publishers. - 1314-4057 .- 1314-4049. ; 4, s. 37-63
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Tidskriftsartikel (refereegranskat)abstract
- Molecular data form an important research tool in most branches of mycology. A non-trivial proportion of the public fungal DNA sequences are, however, compromised in terms of quality and reliability, contributing noise and bias to sequence-borne inferences such as phylogenetic analysis, diversity assessment, and barcoding. In this paper we discuss various aspects and pitfalls of sequence quality assessment. Based on our observations, we provide a set of guidelines to assist in manual quality management of newly generated, near-full-length (Sanger-derived) fungal ITS sequences and to some extent also sequences of shorter read lengths, other genes or markers, and groups of organisms. The guidelines are intentionally non-technical and do not require substantial bioinformatics skills or significant computational power. Despite their simple nature, we feel they would have caught the vast majority of the severely compromised ITS sequences in the public corpus. Our guidelines are nevertheless not infallible, and common sense and intuition remain important elements in the pursuit of compromised sequence data. The guidelines focus on basic sequence authenticity and reliability of the newly generated sequences, and the user may want to consider additional resources and steps to accomplish the best possible quality control. A discussion on the technical resources for further sequence quality management is therefore provided in the supplementary material.
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| 19. |
- Nilsson, R. Henrik, 1976, et al.
(författare)
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Improving ITS sequence data for identification of plant pathogenic fungi
- 2014
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Ingår i: Fungal Diversity. - : Springer Science and Business Media LLC. - 1560-2745 .- 1878-9129. ; 67:1, s. 11-19
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Tidskriftsartikel (refereegranskat)abstract
- Plant pathogenic fungi are a large and diverse assemblage of eukaryotes with substantial impacts on natural ecosystems and human endeavours. These taxa often have complex and poorly understood life cycles, lack observable, discriminatory morphological characters, and may not be amenable to in vitro culturing. As a result, species identification is frequently difficult. Molecular (DNA sequence) data have emerged as crucial information for the taxonomic identification of plant pathogenic fungi, with the nuclear ribosomal internal transcribed spacer (ITS) region being the most popular marker. However, international nucleotide sequence databases are accumulating numerous sequences of compromised or low-resolution taxonomic annotations and substandard technical quality, making their use in the molecular identification of plant pathogenic fungi problematic. Here we report on a concerted effort to identify high-quality reference sequences for various plant pathogenic fungi and to re-annotate incorrectly or insufficiently annotated public ITS sequences from these fungal lineages. A third objective was to enrich the sequences with geographical and ecological metadata. The results – a total of 31,954 changes – are incorporated in and made available through the UNITE database for molecular identification of fungi (http://unite.ut.ee), including standalone FASTA files of sequence data for local BLAST searches, use in the next-generation sequencing analysis platforms QIIME and mothur, and related applications. The present initiative is just a beginning to cover the wide spectrum of plant pathogenic fungi, and we invite all researchers with pertinent expertise to join the annotation effort.
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| 20. |
- Nilsson, R. Henrik, 1976, et al.
(författare)
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Introducing guidelines for publishing DNA-derived occurrence data through biodiversity data platforms
- 2022
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Ingår i: Metabarcoding and Metagenomics. - : Pensoft Publishers. - 2534-9708. ; 6, s. 239-244
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Tidskriftsartikel (refereegranskat)abstract
- DNA sequencing efforts of environmental and other biological samples disclose unprecedented and largely untapped opportunities for advances in the taxonomy, ecology, and geographical distributions of our living world. To realise this potential, DNA-derived occurrence data (notably sequences with dates and coordinates) – much like traditional specimens and observations – need to be discoverable and interpretable through biodiversity data platforms. The Global Biodiversity Information Facility (GBIF) recently headed a community effort to assemble a set of guidelines for publishing DNA-derived data. These guidelines target the principles and approaches of exposing DNA-derived occurrence data in the context of broader biodiversity data. They cover a choice of terms using a controlled vocabulary, common pitfalls, and good practices, without going into platform-specific details. Our hope is that they will benefit anyone interested in better exposure of DNA-derived occurrence data through general biodiversity data platforms, including national biodiversity portals. This paper provides a brief rationale and an overview of the guidelines, an up-to-date version of which is maintained at https://doi.org/10.35035/doc-vf1a-nr22. User feedback and interaction are encouraged as new techniques and best practices emerge.
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| 21. |
- Nilsson, R. Henrik, 1976, et al.
(författare)
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Molecular identification of fungi: rationale, philosophical concerns, and the UNITE database
- 2011
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Ingår i: The Open Applied Informatics Journal. - : Bentham Science Publishers Ltd.. - 1874-1363. ; 5, s. 81-86
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Forskningsöversikt (refereegranskat)abstract
- Fungi form a ubiquitous group of largely inconspicuous organisms that play key ecological roles in terrestrial nutrient cycling. The typically subterranean or otherwise unnoticeable nature of fungal life has left mycology with a partial understanding of fungal biology, and progress is hampered by factors such as the difficulty to delimit species and individuals of fungi and the sparsity of discriminatory morphological and physiological characters for reliable species identification. These and other complications have paved the way for DNA sequence data as an important source of information in mycology, and there are now twenty years’ worth of fungal sequence data available for scientific purposes. However, issues of data reliability and generality impede the use of publicly available fungal DNA sequences. The UNITE database for molecular identification of fungi (http://unite.ut.ee) was built as a response to the difficulties facing anyone seeking to identify environmental samples of fungi to species level using molecular data and the major international sequence databases. The present study describes the UNITE database and examines the role of UNITE in the light of emerging sequencing technologies, notably massively parallel (“454”) pyrosequencing. Environmental sampling of fungi is discussed from a taxonomic perspective.
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| 22. |
- Nilsson, R. Henrik, 1976, et al.
(författare)
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Molecular techniques in mycological studies and sequence data curating: quality control and challenges
- 2016
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Ingår i: Biology of Microfungi. - Switzerland : Springer International Publishing. - 9783319291352 ; , s. 47-64
-
Bokkapitel (refereegranskat)abstract
- Molecular (DNA sequence) data are a routine source of information in mycology. Environmental sequencing efforts of substrates, such as soil, wood, and air, have revealed vast numbers of previously unknown or poorly understood species, and their integration in the classification system of fungi and the fungal tree of life represent significant challenges. Underpinning such efforts are reference datasets of reliable sequences to which newly generated sequences can be compared for taxonomic affiliation and perhaps hints of species traits and ecological roles. The public sequence databases are however accumulating countless sequences that are compromised in terms of taxonomic annotation or technical quality. Metadata on, e.g., country or host of collection and any specimen/culture association are similarly lacking for the majority of entries. This invites further mistakes and reduces scientific explanatory power. This chapter discusses how to spot compromised sequences and what to do when they are found. These curation principles are implemented in the fungal nuclear ribosomal internal transcribed spacer (ITS) sequence database UNITE (http://unite.ut.ee) for molecular identification of fungi. UNITE supports web-based third-party sequence annotation, and the reader is invited to take part in the annotation effort.
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| 23. |
- Nilsson, R. Henrik, 1976, et al.
(författare)
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New features of the UNITE database for molecular identification of fungi
- 2010
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Ingår i: 9th International Mycological Congress, Edinburgh, UK (oral presentation; FESIN/UNITE workshop).
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- New features of the UNITE database for molecular identification of fungi will be introduced. These includes an extractor for ITS1 and ITS2 of the ITS region, a new software package for chimera control, many new ways of representing ecological and geographical metadata - including layered maps - and the possibility to annotate GenBank entries.
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| 24. |
- Nilsson, R. Henrik, 1976, et al.
(författare)
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Taxonomic reliability of DNA sequences in public sequence databases: A fungal perspective
- 2006
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Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 1:1
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Tidskriftsartikel (refereegranskat)abstract
- Background DNA sequences are increasingly seen as one of the primary information sources for species identification in many organism groups. Such approaches, popularly known as barcoding, are underpinned by the assumption that the reference databases used for comparison are sufficiently complete and feature correctly and informatively annotated entries. Methodology/Principal Findings The present study uses a large set of fungal DNA sequences from the inclusive International Nucleotide Sequence Database to show that the taxon sampling of fungi is far from complete, that about 20% of the entries may be incorrectly identified to species level, and that the majority of entries lack descriptive and up-to-date annotations. Conclusions The problems with taxonomic reliability and insufficient annotations in public DNA repositories form a tangible obstacle to sequence-based species identification, and it is manifest that the greatest challenges to biological barcoding will be of taxonomical, rather than technical, nature.
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| 25. |
- Nilsson, R. Henrik, 1976, et al.
(författare)
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The UNITE database for molecular identification of fungi: handling dark taxa and parallel taxonomic classifications.
- 2019
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Ingår i: Nucleic acids research. - : Oxford University Press (OUP). - 1362-4962 .- 0305-1048. ; 47:D1
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Tidskriftsartikel (refereegranskat)abstract
- UNITE (https://unite.ut.ee/) is a web-based database and sequence management environment for the molecular identification of fungi. It targets the formal fungal barcode-the nuclear ribosomal internal transcribed spacer(ITS) region-and offers all ∼1 000000 public fungal ITS sequences for reference. These are clustered into ∼459000 species hypotheses and assigned digital object identifiers (DOIs) to promote unambiguous reference across studies. In-house and web-based third-party sequence curation and annotation have resulted in more than 275000 improvements to the data over the past 15 years. UNITE serves as a data provider for a range of metabarcoding software pipelines and regularly exchanges data with all major fungal sequence databases and other community resources. Recent improvements include redesigned handling of unclassifiable species hypotheses, integration with the taxonomic backbone of the Global Biodiversity Information Facility, and support for an unlimited number of parallel taxonomic classification systems.
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| 26. |
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| 27. |
- Oja, Jane, et al.
(författare)
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Local-scale spatial structure and community composition of orchid mycorrhizal fungi in semi-natural grasslands
- 2017
-
Ingår i: Mycorrhiza. - : Springer Science and Business Media LLC. - 0940-6360 .- 1432-1890. ; 27:4, s. 355-367
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Tidskriftsartikel (refereegranskat)abstract
- Orchid mycorrhizal (OrM) fungi play a crucial role in the ontogeny of orchids, yet little is known about how the structure of OrM fungal communities varies with space and environmental factors. Previous studies suggest that within orchid patches, the distance to adult orchids may affect the abundance of OrM fungi. Many orchid species grow in species-rich temperate semi-natural grasslands, the persistence of which depends on moderate physical disturbances, such as grazing and mowing. The aim of this study was to test whether the diversity, structure and composition of OrM fungal community are influenced by the orchid patches and management intensity in semi-natural grasslands. We detected putative OrM fungi from 0 to 32 m away from the patches of host orchid species (Orchis militaris and Platanthera chlorantha) in 21 semi-natural calcareous grasslands using pyrosequencing. In addition, we assessed different ecological conditions in semi-natural grasslands but primarily focused on the effect of grazing intensity on OrM fungal communities in soil. We found that investigated orchid species were mostly associated with Ceratobasidiaceae and Tulasnellaceae and, to a lesser extent, with Sebacinales. Of all the examined factors, the intensity of grazing explained the largest proportion of variation in OrM fungal as well as total fungal community composition in soil. Spatial analyses showed limited evidence for spatial clustering of OrM fungi and their dependence on host orchids. Our results indicate that habitat management can shape OrM fungal communities, and the spatial distribution of these fungi appears to be weakly structured outside the orchid patches.
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| 28. |
- Ronquist, Fredrik, 1962-, et al.
(författare)
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EU-BON Deliverable 1.3. Systems for mobilizing and managing collection-based data (specimen + DNA-data) fully integrated
- 2016
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Introduction. A large portion of the biodiversity data in natural history collections is still not available digitally. Increasingly, innovative high-throughput methods are being applied to digitize this backlog in bulk, generating large amounts of data. In parallel, natural history museums are becoming increasingly involved in the generation of large amounts of molecular biodiversity data using new massively parallel sequencing platforms. Against this backdrop, the goal of EU BON Task 1.4 has been to support data mobilization efforts targeting collection-based and molecular data, mainly through the development and integration of innovative open-source tools and services.Progress towards objectives. The activities have involved work within the context of three major projects: i) DINA, an open-source, modular, web-based collection management system for natural history specimen data. ii) JACQ an open-access system for botanical (herbarium) data. iii) PlutoF, a web platform for working with traditional and molecular biodiversity research data. The task has also involved work on a number of other EU BON partner systems and services, as well as integration across internal EU BON and external biodiversity informatics resources. Finally, these systems have been used for targeted data mobilization efforts.Achievements and current status. Within DINA, the focus has been on supporting the engineering of sophisticated biodiversity information systems through the exploration of tools supporting distributed development and a modular plug-and-play design based on services-oriented architectures. This has involved the testing and adoption of tools like Apiary for the design of Application Programming Interfaces (APIs) and Docker for systems integration and deployment tasks. A Python library for data migration to DINA was also developed and tested. Within JACQ, a number of tools were developed to facilitate deployment and data migration to the system, and the AnnoSys tool for annotation of data has been integrated. Within PlutoF, EU BON efforts focused on the development of a citizen-science module and improved functionality for the mobilization of collection (living) specimen data. A number of innovative tools were developed by Pensoft to help mobilize biodiversity data published in the scientific literature, including semantic mark-up of species conservation papers, direct import of data from a range of biodiversity platforms into manuscripts, and a mechanism for providing stable links from publications to global biodiversity repositories. Plazi implemented an automated workflow mining published scientific papers for taxonomic data, currently mobilizing 25 % of all published new names as they become available. GlueCad developed apps allowing citizen scientists reporting spontaneous observations or systematic inventory data to select target taxa and preferred data mobilization platform. IBSAS and UCPH have focused on national data mobilization efforts targeting Slovakia and Denmark, respectively.Future developments. Although the development is clearly towards increased integration of biodiversity informatics tools into larger and more sophisticated systems, it is clear that there is no one size that fits all. Nevertheless, the increasingly widespread adoption of community standards, open-source development practises and service-oriented architectures are pushing the capability of current systems forward and facilitating tighter integration across systems. This trend is supported by the appearance of sophisticated tools enabling the design and deployment of complex modular systems. The adoption of the Docker approach is one example of how the biodiversity informatics community may benefit from this.
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| 29. |
- Schoch, Conrad L., et al.
(författare)
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Finding needles in haystacks: linking scientific names, reference specimens and molecular data for Fungi
- 2014
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Ingår i: Database: The Journal of Biological Databases and Curation. - : Oxford University Press (OUP). - 1758-0463. ; 2014:bau061, s. 1-21
-
Tidskriftsartikel (refereegranskat)abstract
- DNA phylogenetic comparisons have shown that morphology-based species recognition often underestimates fungal diversity. Therefore, the need for accurate DNA sequence data, tied to both correct taxonomic names and clearly annotated specimen data, has never been greater. Furthermore, the growing number of molecular ecology and microbiome projects using high-throughput sequencing require fast and effective methods for en masse species assignments. In this article, we focus on selecting and re-annotating a set of marker reference sequences that represent each currently accepted order of Fungi. The particular focus is on sequences from the internal transcribed spacer region in the nuclear ribosomal cistron, derived from type specimens and/or ex-type cultures. Re-annotated and verified sequences were deposited in a curated public database at the National Center for Biotechnology Information (NCBI), namely the RefSeq Targeted Loci (RTL) database, and will be visible during routine sequence similarity searches with NR_prefixed accession numbers. A set of standards and protocols is proposed to improve the data quality of new sequences, and we suggest how type and other reference sequences can be used to improve identification of Fungi.
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| 30. |
- Svantesson, Sten, et al.
(författare)
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Polyozellus vs. Pseudotomentella: generic delimitation with a multi-gene dataset
- 2021
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Ingår i: Fungal Systematics and Evolution. - : Westerdijk Fungal Biodiversity Institute. - 2589-3823. ; 8, s. 143-154
-
Tidskriftsartikel (refereegranskat)abstract
- Polyozellus and Pseudotomentella are two genera of closely related, ectomycorrhizal fungi in the order Thelephorales; the former stipitate and the latter corticioid. Both are widespread in the Northern Hemisphere and many species from both genera seem to be restricted to old growth forest. This study aimed to: a) identify genetic regions useful in inferring the phylogenetic relationship between Polyozellus and Pseudotomentella, b) infer this relationship with the regions identified and c) make any taxonomic changes warranted by the result. RPB2, mtSSU and nearly full-length portions of nrLSU and nrSSU were found to be comparatively easy to sequence and provide a strong phylogenetic signal. A STACEY species tree of these three regions revealed that Polyozellus makes Pseudotomentella paraphyletic. As a result, nearly all species currently placed in Pseudotomentella were recombined to Polyozellus. Pseudotomentella larsenii was found to be closer to Tomentellopsis than Polyozellus, but its placement needs further study and it was hence not recombined.
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| 31. |
- Svantesson, Sten, et al.
(författare)
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Solving the taxonomic identity of Pseudotomentella tristis s.l. (Thelephorales, Basidiomycota) - a multi-gene phylogeny and taxonomic review, integrating ecological and geographical data
- 2019
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Ingår i: Mycokeys. - : Pensoft Publishers. - 1314-4057 .- 1314-4049. ; 50, s. 1-77
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Tidskriftsartikel (refereegranskat)abstract
- P. tristis is an ectomycorrhizal, corticioid fungus whose name is frequently assigned to collections of basidiomata as well as root tip and soil samples from a wide range of habitats and hosts across the northern hemisphere. Despite this, its identity is unclear; eight heterotypic taxa have in major reviews of the species been considered synonymous with or morphologically similar to P. tristis, but no sequence data from type specimens have been available. With the aim to clarify the taxonomy, systematics, morphology, ecology and geographical distribution of P. tristis and its morphologically similar species, we studied their type specimens as well as 147 basidiomata collections of mostly North European material. We used gene trees generated in BEAST 2 and PhyML and species trees estimated in STACEY and ASTRAL to delimit species based on the ITS, LSU, Tef1 alpha and mtSSU regions. We enriched our sampling with environmental ITS sequences from the UNITE database. We found the P. tristis group to contain 13 molecularly and morphologically distinct species. Three of these, P. tristis, P. umbrina and P. atrofusca, are already known to science, while ten species are here described as new: P. sciastra sp. nov., P. tristoides sp. nov., P. umbrinascens sp. nov., P. pinophila sp. nov., P. alnophila sp. nov., P. alobata sp. nov., P. pluriloba sp. nov., P. abundiloba sp. nov., P. rotundispora sp. nov. and P. media sp. nov. We discovered P. rhizopunctata and P. atrofusca to form a sister clade to all other species in P. tristis s.l. These two species, unlike all other species in the P. tristis complex, are dimitic. In this study, we designate epitypes for P. tristis, P. umbrina and Hypochnopsis fuscata and lectotypes for Auricularia phylacteris and Thelephora biennis. We show that the holotype of Hypochnus sitnensis and the lectotype of Hypochnopsis fuscata are conspecific with P. tristis, but in the absence of molecular information we regard Pseudotomentella longisterigmata and Hypochnus rhacodium as doubtful taxa due to their aberrant morphology. We confirm A. phylacteris, Tomentella biennis and Septobasidium arachnoideum as excluded taxa, since their morphology clearly show that they belong to other genera. A key to the species of the P. tristis group is provided. We found P. umbrina to be a common species with a wide, Holarctic distribution, forming ectomycorrhiza with a large number of host species in habitats ranging from tropical forests to the Arctic tundra. The other species in the P. tristis group were found to be less common and have narrower ecological niches.
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| 32. |
- Tedersoo, L., et al.
(författare)
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454 Pyrosequencing and Sanger sequencing of tropical mycorrhizal fungi provide similar results but reveal substantial methodological biases
- 2010
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Ingår i: New Phytologist. - : Wiley. - 0028-646X. ; 188:1, s. 291-301
-
Tidskriftsartikel (refereegranskat)abstract
- Compared with Sanger sequencing-based methods, pyrosequencing provides orders of magnitude more data on the diversity of organisms in their natural habitat, but its technological biases and relative accuracy remain poorly understood. This study compares the performance of pyrosequencing and traditional sequencing for species’ recovery of ectomycorrhizal fungi on root tips in a Cameroonian rain forest and addresses biases related to multi-template PCR and pyrosequencing analyses. Pyrosequencing and the traditional method yielded qualitatively similar results, but there were slight, but significant, differences that affected the taxonomic view of the fungal community. We found that most pyrosequencing singletons were artifactual and contained a strongly elevated proportion of insertions compared with natural intra- and interspecific variation. The alternative primers, DNA extraction methods and PCR replicates strongly influenced the richness and community composition as recovered by pyrosequencing. Pyrosequencing offers a powerful alternative for the identification of ectomycorrhizal fungi in pooled root samples, but requires careful selection of molecular tools. A well-populated backbone database facilitates the detection of biological and technical artifacts. The pyrosequencing pipeline is available at http://unite.ut.ee/454pipeline.tgz.
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| 33. |
- Tedersoo, Leho, et al.
(författare)
-
Genomics and metagenomics technologies to recover ribosomal DNA and single-copy genes from old fruit-body and ectomycorrhiza specimens
- 2016
-
Ingår i: MycoKeys. - : Pensoft Publishers. - 1314-4057 .- 1314-4049. ; :13, s. 1-20
-
Tidskriftsartikel (refereegranskat)abstract
- High-throughput sequencing (HTS) has become a standard technique for genomics, metagenomics and taxonomy, but these analyses typically require large amounts of high-quality DNA that is difficult to obtain from uncultivable organisms including fungi with no living culture or fruit-body representatives. By using 1 ng DNA and low coverage Illumina HiSeqHTS, we evaluated the usefulness of genomics and metagenomics tools to recover fungal barcoding genes from old and problematic specimens of fruit-bodies and ectomycorrhizal (EcM) root tips. Ribosomal DNA and single-copy genes were successfully recovered from both fruit-body and EcM specimens typically <10 years old (maximum, 17 years). Samples with maximum obtained DNA concentration <0.2 ng µl-1 were sequenced poorly. Fungal rDNA molecules assembled from complex mock community and soil revealed a large proportion of chimeras and artefactual consensus sequences of closely related taxa. Genomics and metagenomics tools enable recovery of fungal genomes from very low initial amounts of DNA from fruit-bodies and ectomycorrhizas, but these genomes include a large proportion of prokaryote and other eukaryote DNA. Nonetheless, the recovered scaffolds provide an important source for phylogenetic and phylogenomic analyses and mining of functional genes.
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| 34. |
- Tedersoo, Leho, et al.
(författare)
-
Global biogeography of the ectomycorrhizal/sebacina lineage (Fungi, Sebacinales) as revealed from comparative phylogenetic analyses
- 2014
-
Ingår i: Molecular Ecology. - : Wiley. - 0962-1083 .- 1365-294X. ; 23:16, s. 4168-4183
-
Tidskriftsartikel (refereegranskat)abstract
- Compared with plants and animals, large-scale biogeographic patterns of microbes including fungi are poorly understood. By the use of a comparative phylogenetic approach and ancestral state reconstructions, we addressed the global biogeography, rate of evolution and evolutionary origin of the widely distributed ectomycorrhizal (EcM) /sebacina lineage that forms a large proportion of the Sebacinales order. We downloaded all publicly available internal transcribed spacer (ITS) sequences and metadata and supplemented sequence information from three genes to construct dated phylogenies and test biogeographic hypotheses. The /sebacina lineage evolved 45-57Myr ago that groups it with relatively young EcM taxa in other studies. The most parsimonious origin for /sebacina is inferred to be North American temperate coniferous forests. Among biogeographic traits, region and biome exhibited stronger phylogenetic signal than host family. Consistent with the resource availability (environmental energy) hypothesis, the ITS region is evolving at a faster rate in tropical than nontropical regions. Most biogeographic regions exhibited substantial phylogenetic clustering suggesting a strong impact of dispersal limitation over a large geographic scale. In northern Holarctic regions, however, phylogenetic distances and phylogenetic grouping of isolates indicate multiple recent dispersal events.
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| 35. |
- Tedersoo, Leho, et al.
(författare)
-
Global diversity and geography of soil fungi
- 2014
-
Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 346:6213, s. artikel nr 1256688-
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Tidskriftsartikel (refereegranskat)abstract
- Fungi play major roles in ecosystem processes, but the determinants of fungal diversity and biogeographic patterns remain poorly understood. Using DNA metabarcoding data from hundreds of globally distributed soil samples, we demonstrate that fungal richness is decoupled from plant diversity. The plant-to-fungus richness ratio declines exponentially toward the poles. Climatic factors, followed by edaphic and spatial variables, constitute the best predictors of fungal richness and community composition at the global scale. Fungi show similar latitudinal diversity gradients to other organisms, with several notable exceptions. These findings advance our understanding of global fungal diversity patterns and permit integration of fungi into a general macroecological framework.
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| 36. |
- Tedersoo, Leho, et al.
(författare)
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Global patterns in endemicity and vulnerability of soil fungi.
- 2022
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Ingår i: Global change biology. - : Wiley. - 1365-2486 .- 1354-1013. ; 28:22, s. 6696-6710
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Tidskriftsartikel (refereegranskat)abstract
- Fungi are highly diverse organisms, which provide multiple ecosystem services. However, compared with charismatic animals and plants, the distribution patterns and conservation needs of fungi have been little explored. Here, we examined endemicity patterns, global change vulnerability and conservation priority areas for functional groups of soil fungi based on six global surveys using a high-resolution, long-read metabarcoding approach. We found that the endemicity of all fungi and most functional groups peaks in tropical habitats, including Amazonia, Yucatan, West-Central Africa, Sri Lanka, and New Caledonia, with a negligible island effect compared with plants and animals. We also found that fungi are predominantly vulnerable to drought, heat and land-cover change, particularly in dry tropical regions with high human population density. Fungal conservation areas of highest priority include herbaceous wetlands, tropical forests, and woodlands. We stress that more attention should be focused on the conservation of fungi, especially root symbiotic arbuscular mycorrhizal and ectomycorrhizal fungi in tropical regions as well as unicellular early-diverging groups and macrofungi in general. Given the low overlap between the endemicity of fungi and macroorganisms, but high conservation needs in both groups, detailed analyses on distribution and conservation requirements are warranted for other microorganisms and soil organisms.
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| 37. |
- Tedersoo, Leho, et al.
(författare)
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High-level classification of the Fungi and a tool for evolutionary ecological analyses
- 2018
-
Ingår i: Fungal diversity. - : SPRINGER. - 1560-2745 .- 1878-9129. ; 90:1, s. 135-159
-
Tidskriftsartikel (refereegranskat)abstract
- High-throughput sequencing studies generate vast amounts of taxonomic data. Evolutionary ecological hypotheses of the recovered taxa and Species Hypotheses are difficult to test due to problems with alignments and the lack of a phylogenetic backbone. We propose an updated phylum-and class-level fungal classification accounting for monophyly and divergence time so that the main taxonomic ranks are more informative. Based on phylogenies and divergence time estimates, we adopt phylum rank to Aphelidiomycota, Basidiobolomycota, Calcarisporiellomycota, Glomeromycota, Entomophthoromycota, Entorrhizomycota, Kickxellomycota, Monoblepharomycota, Mortierellomycota and Olpidiomycota. We accept nine subkingdoms to accommodate these 18 phyla. We consider the kingdom Nucleariae (phyla Nuclearida and Fonticulida) as a sister group to the Fungi. We also introduce a perl script and a newick-formatted classification backbone for assigning Species Hypotheses into a hierarchical taxonomic framework, using this or any other classification system. We provide an example of testing evolutionary ecological hypotheses based on a global soil fungal data set.
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| 38. |
- Tedersoo, Leho, et al.
(författare)
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Response to Comment on “Global diversity and geography of soil fungi”
- 2015
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 349:6251
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Schadt and Rosling (Technical Comment, 26 June 2015, p. 1438) argue that primer-template mismatches neglected the fungal class Archaeorhizomycetes in a global soil survey. Amplicon-based metabarcoding of nine barcode-primer pair combinations and polymerase chain reaction (PCR)–free shotgun metagenomics revealed that barcode and primer choice and PCR bias drive the diversity and composition of microorganisms in general, but the Archaeorhizomycetes were little affected in the global study. We urge that careful choice of DNA markers and primers is essential for ecological studies using high-throughput sequencing for identification.
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| 39. |
- Tedersoo, Leho, et al.
(författare)
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Shotgun metagenomes and multiple primer pair-barcode combinations of amplicons reveal biases in metabarcoding analyses of fungi
- 2015
-
Ingår i: MycoKeys. - : Pensoft Publishers. - 1314-4057 .- 1314-4049. ; 10, s. 1-43
-
Tidskriftsartikel (refereegranskat)abstract
- Rapid development of high-throughput (HTS) molecular identification methods has revolutionized our knowledge about taxonomic diversity and ecology of fungi. However, PCR-based methods exhibit multiple technical shortcomings that may bias our understanding of the fungal kingdom. This study was initiated to quantify potential biases in fungal community ecology by comparing the relative performance of amplicon-free shotgun metagenomics and amplicons of nine primer pairs over seven nuclear ribosomal DNA (rDNA) regions often used in metabarcoding analyses. The internal transcribed spacer (ITS) barcodes ITS1 and ITS2 provided greater taxonomic and functional resolution and richness of operational taxonomic units (OTUs) at the 97% similarity threshold compared to barcodes located within the ribosomal small subunit (SSU) and large subunit (LSU) genes. All barcode-primer pair combinations provided consistent results in ranking taxonomic richness and recovering the importance of floristic variables in driving fungal community composition in soils of Papua New Guinea. The choice of forward primer explained up to 2.0% of the variation in OTU-level analysis of the ITS1 and ITS2 barcode data sets. Across the whole data set, barcode-primer pair combination explained 37.6–38.1% of the variation, which surpassed any environmental signal. Overall, the metagenomics data set recovered a similar taxonomic overview, but resulted in much lower fungal rDNA sequencing depth, inability to infer OTUs, and high uncertainty in identification. We recommend the use of ITS2 or the whole ITS region for metabarcoding and we advocate careful choice of primer pairs in consideration of the relative proportion of fungal DNA and expected dominant groups.
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| 40. |
- Tedersoo, Leho, et al.
(författare)
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Spatial structure and the effects of host and soil environments on communities of ectomycorrhizal fungi in wooded savannas and rain forests of Continental Africa and Madagascar
- 2011
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Ingår i: Molecular Ecology. - 0962-1083 .- 1365-294X. ; 20:14, s. 3071-3080
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Tidskriftsartikel (refereegranskat)abstract
- Mycorrhizal fungi play a key role in mineral nutrition of terrestrial plants, but the factors affecting natural distribution, diversity and community composition of particularly tropical fungi remain poorly understood. This study addresses shifts in community structure and species frequency of ectomycorrhizal (EcM) fungi in relation to host taxa, soil depth and spatial structure in four contrasting African ecosystems. We used the rDNA and plastid trnL intron sequence analysis for identification of fungi and host plants, respectively. By partitioning out spatial autocorrelation in plant and fungal distribution, we suggest that African EcM fungal communities are little structured by soil horizon and host at the plant species and family levels. These findings contrast with patterns of vegetation in these forests and EcM fungal communities in other tropical and temperate ecosystems. The low level of host preference indirectly supports an earlier hypothesis that pioneer Phyllanthaceae may facilitate the establishment of late successional Fabaceae and potentially other EcM host trees by providing compatible fungal inoculum in deforested and naturally disturbed ecosystems of tropical Africa.
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| 41. |
- Tedersoo, Leho, et al.
(författare)
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Standardizing metadata and taxonomic identification in metabarcoding studies
- 2015
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Ingår i: GigaScience. - : Oxford University Press (OUP). - 2047-217X .- 2047-217X. ; 4
-
Tidskriftsartikel (refereegranskat)abstract
- High-throughput sequencing-based metabarcoding studies produce vast amounts of ecological data, but a lack of consensus on standardization of metadata and how to refer to the species recovered severely hampers reanalysis and comparisons among studies. Here we propose an automated workflow covering data submission, compression, storage and public access to allow easy data retrieval and inter-study communication. Such standardized and readily accessible datasets facilitate data management, taxonomic comparisons and compilation of global metastudies.
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| 42. |
- Tedersoo, Leho, et al.
(författare)
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Tidying up international nucleotide sequence databases: ecological, geographical and sequence quality annotation of ITS sequences of mycorrhizal fungi
- 2011
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Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 6:9
-
Tidskriftsartikel (refereegranskat)abstract
- Sequence analysis of the ribosomal RNA operon, particularly the internal transcribed spacer (ITS) region, provides a powerful tool for identification of mycorrhizal fungi. The sequence data deposited in the International Nucleotide Sequence Databases (INSD) are, however, unfiltered for quality and are often poorly annotated with metadata. To detect chimeric and low-quality sequences and assign the ectomycorrhizal fungi to phylogenetic lineages, fungal ITS sequences were downloaded from INSD, aligned within family-level groups, and examined through phylogenetic analyses and BLAST searches. By combining the fungal sequence database UNITE and the annotation and search tool PlutoF, we also added metadata from the literature to these accessions. Altogether 35,632 sequences belonged to mycorrhizal fungi or originated from ericoid and orchid mycorrhizal roots. Of these sequences, 677 were considered chimeric and 2,174 of low read quality. Information detailing country of collection, geographical coordinates, interacting taxon and isolation source were supplemented to cover 78.0%, 33.0%, 41.7% and 96.4% of the sequences, respectively. These annotated sequences are publicly available via UNITE (http://unite.ut.ee/) for downstream biogeographic, ecological and taxonomic analyses. In European Nucleotide Archive (ENA; http://www.ebi.ac.uk/ena/), the annotated sequences have a special link-out to UNITE. We intend to expand the data annotation to additional genes and all taxonomic groups and functional guilds of fungi.
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| 43. |
- Tedersoo, Leho, et al.
(författare)
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Towards global patterns in the diversity and community structure of ectomycorrhizal fungi.
- 2012
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Ingår i: Molecular Ecology. - 0962-1083 .- 1365-294X. ; 21:17, s. 4160-70
-
Tidskriftsartikel (refereegranskat)abstract
- Global species richness patterns of soil micro-organisms remain poorly understood compared to macro-organisms. We use a global analysis to disentangle the global determinants of diversity and community composition for ectomycorrhizal (EcM) fungi-microbial symbionts that play key roles in plant nutrition in most temperate and many tropical forest ecosystems. Host plant family has the strongest effect on the phylogenetic community composition of fungi, whereas temperature and precipitation mostly affect EcM fungal richness that peaks in the temperate and boreal forest biomes, contrasting with latitudinal patterns of macro-organisms. Tropical ecosystems experience rapid turnover of organic material and have weak soil stratification, suggesting that poor habitat conditions may contribute to the relatively low richness of EcM fungi, and perhaps other soil biota, in most tropical ecosystems. For EcM fungi, greater evolutionary age and larger total area of EcM host vegetation may also contribute to the higher diversity in temperate ecosystems. Our results provide useful biogeographic and ecological hypotheses for explaining the distribution of fungi that remain to be tested by involving next-generation sequencing techniques and relevant soil metadata.
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| 44. |
- Zamora, Juan Carlos, et al.
(författare)
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Considerations and consequences of allowing DNA sequence data as types of fungal taxa
- 2018
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Ingår i: IMA Fungus. - : INT MYCOLOGICAL ASSOC. - 2210-6340 .- 2210-6359. ; 9:1, s. 167-185
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Tidskriftsartikel (refereegranskat)abstract
- Nomenclatural type definitions are one of the most important concepts in biological nomenclature. Being physical objects that can be re-studied by other researchers, types permanently link taxonomy (an artificial agreement to classify biological diversity) with nomenclature (an artificial agreement to name biological diversity). Two proposals to amend the International Code of Nomenclature for algae, fungi, and plants (ICN), allowing DNA sequences alone (of any region and extent) to serve as types of taxon names for voucherless fungi (mainly putative taxa from environmental DNA sequences), have been submitted to be voted on at the 11th International Mycological Congress (Puerto Rico, July 2018). We consider various genetic processes affecting the distribution of alleles among taxa and find that alleles may not consistently and uniquely represent the species within which they are contained. Should the proposals be accepted, the meaning of nomenclatural types would change in a fundamental way from physical objects as sources of data to the data themselves. Such changes are conducive to irreproducible science, the potential typification on artefactual data, and massive creation of names with low information content, ultimately causing nomenclatural instability and unnecessary work for future researchers that would stall future explorations of fungal diversity. We conclude that the acceptance of DNA sequences alone as types of names of taxa, under the terms used in the current proposals, is unnecessary and would not solve the problem of naming putative taxa known only from DNA sequences in a scientifically defensible way. As an alternative, we highlight the use of formulas for naming putative taxa (candidate taxa) that do not require any modification of the ICN.
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