Nejvíce citovaný článek - PubMed ID 30442909
Mycobiome diversity: high-throughput sequencing and identification of fungi
The nuclear ribosomal DNA Internal Transcribed Spacer (ITS) region is used as a universal fungal barcode marker, but often lacks a significant DNA barcoding gap between sister taxa. Here we tested the reliability of protein coding low-copy genes as alternative barcode markers. Mock communities of three unrelated agaric genera (Dermoloma, Hodophilus, and Russula) representing lineages of closely related species were sequenced by the Illumina platform targeting the ITS1, ITS2, the second largest subunit of RNA polymerase II gene (rpb2) and the transcription elongation factor 1-alpha gene (ef1-α) regions. Species representation and their relative abundances were similar across all tested barcode regions, despite a lower copy number in protein coding markers. ITS1 and ITS2 required more sophisticated sequence filtering because they produced a high number of chimeric sequences requiring reference-based chimera removal and had a higher number of sequence variants per species. Although clustering of filtered ITS sequences resulted in an average higher number of correctly clustered units at optimal similarity thresholds, these thresholds varied substantially among genera. Best-fitted thresholds of low-copy markers were more consistent across genera but frequently lacked species resolution due to low intraspecific variability. At some thresholds, we observed multiple species lumped together, and at the same time, species split into multiple partial clusters, which should be taken into consideration when assessing the best clustering thresholds and taxonomic identity of clusters. To achieve the best taxonomic resolution and improve species detection, we recommend combining different markers and applying additional reference-based sorting of clusters. The current availability of rpb2 and ef1-α reference sequences in public databases is far from being complete for all fungal groups, but a combined marker approach can be used for group-specific studies that can build reference data for their own purposes.
- Klíčová slova
- amplicon abundance, chimera, sympatric species, threshold,
- Publikační typ
- časopisecké články MeSH
Environmental DNA (eDNA) metabarcoding has gained growing attention as a strategy for monitoring biodiversity in ecology. However, taxa identifications produced through metabarcoding require sophisticated processing of high-throughput sequencing data from taxonomically informative DNA barcodes. Various sets of universal and taxon-specific primers have been developed, extending the usability of metabarcoding across archaea, bacteria and eukaryotes. Accordingly, a multitude of metabarcoding data analysis tools and pipelines have also been developed. Often, several developed workflows are designed to process the same amplicon sequencing data, making it somewhat puzzling to choose one among the plethora of existing pipelines. However, each pipeline has its own specific philosophy, strengths and limitations, which should be considered depending on the aims of any specific study, as well as the bioinformatics expertise of the user. In this review, we outline the input data requirements, supported operating systems and particular attributes of thirty-two amplicon processing pipelines with the goal of helping users to select a pipeline for their metabarcoding projects.
- Klíčová slova
- amplicon data analysis, bioinformatics, environmental DNA, metabarcoding, pipeline, review,
- MeSH
- analýza dat MeSH
- Archaea genetika klasifikace MeSH
- Bacteria genetika klasifikace MeSH
- environmentální DNA genetika MeSH
- Eukaryota genetika klasifikace MeSH
- metagenomika metody MeSH
- software * MeSH
- taxonomické DNA čárové kódování * metody MeSH
- výpočetní biologie * metody MeSH
- vysoce účinné nukleotidové sekvenování metody MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- environmentální DNA MeSH
BACKGROUND: Grasslands provide fundamental ecosystem services that are supported by their plant diversity. However, the importance of plant taxonomic diversity for the diversity of other taxa in grasslands remains poorly understood. Here, we studied the associations between plant communities, soil chemistry and soil microbiome in a wooded meadow of Čertoryje (White Carpathians, Czech Republic), a European hotspot of plant species diversity. RESULTS: High plant diversity was associated with treeless grassland areas with high primary productivity and high contents of soil nitrogen and organic carbon. In contrast, low plant diversity occurred in grasslands near solitary trees and forest edges. Fungal communities differed between low-diversity and high-diversity grasslands more strongly than bacterial communities, while the difference in arbuscular mycorrhizal fungi (AMF) depended on their location in soil versus plant roots. Compared to grasslands with low plant diversity, high-diversity plant communities had a higher diversity of fungi including soil AMF, a different fungal and soil AMF community composition and higher bacterial and soil AMF biomass. Root AMF composition differed only slightly between grasslands with low and high plant diversity. Trees dominated the belowground plant community in low-diversity grasslands, which influenced microbial diversity and composition. CONCLUSIONS: The determinants of microbiome abundance and composition in grasslands are complex. Soil chemistry mainly influenced bacterial communities, while plant community type mainly affected fungal (including AMF) communities. Further studies on the functional roles of microbial communities are needed to understand plant-soil-microbe interactions and their involvement in grassland ecosystem services.
- Klíčová slova
- Arbuscular mycorrhizal fungi, Bacterial 16S rRNA, Fungal ITS, Plant diversity, Semi-natural grassland,
- Publikační typ
- časopisecké články MeSH
Despite the diligent efforts of libraries, archives, and similar institutions to preserve cultural monuments, biodeterioration continues to pose a significant threat to these objects. One of the main sources of microorganisms responsible for the biodeterioration process is the presence of airborne microorganisms. Therefore, this research aims to monitor and compare outcomes of both culture-dependent (utilising various cultivation strategies) and culture-independent approaches (RNA-based sequencing) to identifying metabolically active airborne microorganisms in archives in the Czech Republic. Through this study, several species that have the potential to pose risks to both cultural heritage objects and the health of institution employees were found. Additionally, the efficacy of different cultivation media was demonstrated to be varied across archive rooms, highlighting the necessity of employing multiple cultivation media for comprehensive analyses. Of noteworthy importance, the resuscitating-promoting factor (Rpf) proved to be a pivotal tool, increasing bacterial culturability by up to 30% when synergistically employed Reasoner's 2A agar (R2A) and R2A + Rpf media. Next, the study emphasises the importance of integrating both culture-dependent and culture-independent approaches. The overlap between genera identified by the culture-dependent approach and those identified also by the culture-independent approach varied from 33% to surpassing 94%, with the maximum alignment exceeding 94% in only one case. Our results highlight the importance of actively monitoring and assessing levels of microbial air contamination in archives to prevent further deterioration of cultural heritage objects and to promote improved conditions for employees in archives and similar institutions.
- Klíčová slova
- Culture-dependent approach, Illumina MiSeq, Increasing culturability, Microbial air analysis, RNA analysis,
- Publikační typ
- časopisecké články MeSH
Fungal conservation is gaining momentum globally, but many challenges remain. To advance further, more data are needed on fungal diversity across space and time. Fundamental information regarding population sizes, trends, and geographic ranges is also critical to accurately assess the extinction risk of individual species. However, obtaining these data is particularly difficult for fungi due to their immense diversity, complex and problematic taxonomy, and cryptic nature. This paper explores how citizen science (CS) projects can be lever-aged to advance fungal conservation efforts. We present several examples of past and ongoing CS-based projects to record and monitor fungal diversity. These include projects that are part of broad collecting schemes, those that provide participants with targeted sampling methods, and those whereby participants collect environmental samples from which fungi can be obtained. We also examine challenges and solutions for how such projects can capture fungal diversity, estimate species absences, broaden participation, improve data curation, and translate resulting data into actionable conservation measures. Finally, we close the paper with a call for professional mycologists to engage with amateurs and local communities, presenting a framework to determine whether a given project would likely benefit from participation by citizen scientists.
- Klíčová slova
- Red List, amateurs, extinction risk, fungal distribution, iNaturalist, mycology, online databases,
- Publikační typ
- časopisecké články MeSH
Many orchid species are endangered due to anthropogenic pressures such as habitat destruction and overharvesting, meanwhile, all orchids rely on orchid mycorrhizal fungi (OMF) for seed germination and seedling growth. Therefore, a better understanding of this intimate association is crucial for orchid conservation. Isolation and identification of OMF remain challenging as many fungi are unculturable. In our study, we tested the efficiency of both culture-dependent and culture-independent methods to describe OMF diversity in multiple temperate orchids and assessed any phylogenetic patterns in cultivability. The culture-dependent method involved the cultivation and identification of single pelotons (intracellular hyphal coils), while the culture-independent method used next-generation sequencing (NGS) to identify root-associated fungal communities. We found that most orchid species were associated with multiple fungi, and the orchid host had a greater impact than locality on the variability in fungal communities. The culture-independent method revealed greater fungal diversity than the culture-dependent one, but despite the lower detection, the isolated fungal strains were the most abundant OMF in adult roots. Additionally, the abundance of NGS reads of cultured OTUs was correlated with the extent of mycorrhizal root colonization in orchid plants. Finally, this limited-scale study tentatively suggests that the cultivability character of OMF may be randomly distributed along the phylogenetic trees of the rhizoctonian families.
- Klíčová slova
- Ceratobasidiaceae, Orchidaceae, Serendipitaceae, Tulasnellaceae, culture-independent and -dependent methods, fungal phylogeny, metabarcoding, mycorrhizal fungi,
- Publikační typ
- časopisecké články MeSH
Soil fungi play indispensable roles in all ecosystems including the recycling of organic matter and interactions with plants, both as symbionts and pathogens. Past observations and experimental manipulations indicate that projected global change effects, including the increase of CO2 concentration, temperature, change of precipitation and nitrogen (N) deposition, affect fungal species and communities in soils. Although the observed effects depend on the size and duration of change and reflect local conditions, increased N deposition seems to have the most profound effect on fungal communities. The plant-mutualistic fungal guilds - ectomycorrhizal fungi and arbuscular mycorrhizal fungi - appear to be especially responsive to global change factors with N deposition and warming seemingly having the strongest adverse effects. While global change effects on fungal biodiversity seem to be limited, multiple studies demonstrate increases in abundance and dispersal of plant pathogenic fungi. Additionally, ecosystems weakened by global change-induced phenomena, such as drought, are more vulnerable to pathogen outbreaks. The shift from mutualistic fungi to plant pathogens is likely the largest potential threat for the future functioning of natural and managed ecosystems. However, our ability to predict global change effects on fungi is still insufficient and requires further experimental work and long-term observations. Citation: Baldrian P, Bell-Dereske L, Lepinay C, Větrovský T, Kohout P (2022). Fungal communities in soils under global change. Studies in Mycology 103: 1-24. doi: 10.3114/sim.2022.103.01.
- Klíčová slova
- deposition, drought, elevated CO2, global change, mycorrhiza, nitrogen, warming,
- Publikační typ
- časopisecké články MeSH
Understanding and describing the diversity of living organisms is a great challenge. Fungi have for a long time been, and unfortunately still are, underestimated when it comes to taxonomic research. The foundations were laid by the first mycologists through field observations. These important fundamental works have been and remain vital reference works. Nevertheless, a non-negligible part of the studied funga escaped their attention. Thanks to modern developments in molecular techniques, the study of fungal diversity has been revolutionized in terms of tools and knowledge. Despite a number of disadvantages inherent to these techniques, traditional field-based inventory work has been increasingly superseded and neglected. This perspective aims to demonstrate the central importance of field-based research in fungal diversity studies, and encourages researchers not to be blinded by the sole use of molecular methods.
- Klíčová slova
- fieldwork, fungal conservation, fungal diversity, genetics, monitoring, taxonomy,
- Publikační typ
- časopisecké články MeSH
In the context of a recent massive increase in research on plant root functions and their impact on the environment, root ecologists currently face many important challenges to keep on generating cutting-edge, meaningful and integrated knowledge. Consideration of the below-ground components in plant and ecosystem studies has been consistently called for in recent decades, but methodology is disparate and sometimes inappropriate. This handbook, based on the collective effort of a large team of experts, will improve trait comparisons across studies and integration of information across databases by providing standardised methods and controlled vocabularies. It is meant to be used not only as starting point by students and scientists who desire working on below-ground ecosystems, but also by experts for consolidating and broadening their views on multiple aspects of root ecology. Beyond the classical compilation of measurement protocols, we have synthesised recommendations from the literature to provide key background knowledge useful for: (1) defining below-ground plant entities and giving keys for their meaningful dissection, classification and naming beyond the classical fine-root vs coarse-root approach; (2) considering the specificity of root research to produce sound laboratory and field data; (3) describing typical, but overlooked steps for studying roots (e.g. root handling, cleaning and storage); and (4) gathering metadata necessary for the interpretation of results and their reuse. Most importantly, all root traits have been introduced with some degree of ecological context that will be a foundation for understanding their ecological meaning, their typical use and uncertainties, and some methodological and conceptual perspectives for future research. Considering all of this, we urge readers not to solely extract protocol recommendations for trait measurements from this work, but to take a moment to read and reflect on the extensive information contained in this broader guide to root ecology, including sections I-VII and the many introductions to each section and root trait description. Finally, it is critical to understand that a major aim of this guide is to help break down barriers between the many subdisciplines of root ecology and ecophysiology, broaden researchers' views on the multiple aspects of root study and create favourable conditions for the inception of comprehensive experiments on the role of roots in plant and ecosystem functioning.
- Klíčová slova
- below-ground ecology, handbook, plant root functions, protocol, root classification, root ecology, root traits, trait measurements,
- MeSH
- databáze faktografické MeSH
- ekologie MeSH
- ekosystém * MeSH
- fenotyp MeSH
- rostliny * MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
Fungal metabolic carbon acquisition and its subsequent partitioning between biomass production and respiration, i.e. the carbon-use efficiency (CUE), are central parameters in biogeochemical modeling. However, current available techniques for estimating these parameters are all associated with practical and theoretical shortcomings, making assessments unreliable. Gene expression analyses hold the prospect of phenotype prediction by indirect means, providing new opportunities to obtain information about metabolic priorities. We cultured four different fungal isolates (Chalara longipes, Laccaria bicolor, Serpula lacrymans and Trichoderma harzianum) in liquid media with contrasting nitrogen availability and measured growth rates and respiration to calculate CUE. By relating gene expression markers to measured carbon fluxes, we identified genes coding for 1,3-β-glucan synthase and 2-oxoglutarate dehydrogenase as suitable markers for growth and respiration, respectively, capturing both intraspecific variation as well as within-strain variation dependent on growth medium. A transcript index based on these markers correlated significantly with differences in CUE between the fungal isolates. Our study paves the way for the use of these markers to assess differences in growth, respiration and CUE in natural fungal communities, using metatranscriptomic or the RT-qPCR approach.
- Klíčová slova
- carbon-use efficiency, fungi, gene markers, growth, metatranscriptomics, respiration,
- MeSH
- Ascomycota genetika metabolismus MeSH
- Basidiomycota genetika MeSH
- biologické markery * analýza MeSH
- fungální proteiny * genetika metabolismus MeSH
- houby * genetika metabolismus MeSH
- Hypocreales genetika metabolismus MeSH
- Laccaria genetika metabolismus MeSH
- transkriptom * MeSH
- Trichoderma genetika metabolismus MeSH
- uhlík * metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- biologické markery * MeSH
- fungální proteiny * MeSH
- uhlík * MeSH