Metagenomics Dotaz Zobrazit nápovědu
Rock varnish is a microbial habitat, characterised by thin (5-500 μm) and shiny coatings of iron (Fe) and manganese (Mn) oxides associated with clay minerals. This structure is well studied by geologists, and recently there have been reports about the taxonomical composition of its microbiome. In this study, we investigated the rock varnish microbiome using shotgun metagenomics together with analyses of elemental composition, lipid and small molecule biomarkers, and rock surface analyses to explore the biogeography of microbial communities and their functional features. We report taxa and encoded functions represented in metagenomes retrieved from varnish or non-varnish samples, additionally, eight nearly complete genomes have been reconstructed spanning four phyla (Acidobacteria, Actinobacteria, Chloroflexi and TM7). The functional and taxonomic analyses presented in this study provide new insights into the ecosystem dynamics and survival strategies of microbial communities inhabiting varnish and non-varnish rock surfaces.
- MeSH
- Acidobacteria genetika MeSH
- Actinobacteria genetika MeSH
- Chloroflexi genetika MeSH
- genom bakteriální genetika MeSH
- metagenom genetika MeSH
- metagenomika metody MeSH
- mikrobiota fyziologie MeSH
- nátěrové hmoty MeSH
- oxidy MeSH
- půdní mikrobiologie * MeSH
- sloučeniny manganu MeSH
- železo MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Despite several efforts to unravel the microbial diversity of soil, most microbes are still unknown. A recent large-scale effort based on genome-resolved metagenomics by Nayfach et al. has demonstrated how this approach can expand our understanding of novel bacterial lineages, including those from soils. Genomic catalogs of soil microbiomes are now enabling a deeper investigation of the evolutionary and functional role of high-complex soil microbiomes, promoting new knowledge from the reuse and sharing of multi-omics data.
Microbial biodegradation and biotransformation reactions are essential to most bioremediation processes, yet the specific organisms, genes, and mechanisms involved are often not well understood. Stable isotope probing (SIP) enables researchers to directly link microbial metabolic capability to phylogenetic and metagenomic information within a community context by tracking isotopically labeled substances into phylogenetically and functionally informative biomarkers. SIP is thus applicable as a tool for the identification of active members of the microbial community and associated genes integral to the community functional potential, such as biodegradative processes. The rapid evolution of SIP over the last decade and integration with metagenomics provide researchers with a much deeper insight into potential biodegradative genes, processes, and applications, thereby enabling an improved mechanistic understanding that can facilitate advances in the field of bioremediation.
- MeSH
- biodegradace * MeSH
- fylogeneze MeSH
- izotopové značení metody MeSH
- látky znečišťující životní prostředí metabolismus MeSH
- metagenomika metody trendy MeSH
- uhlík metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Research Support, N.I.H., Extramural MeSH
- MeSH
- Bacteria * klasifikace MeSH
- biodegradace * MeSH
- buněčné kultury * metody přístrojové vybavení využití MeSH
- genetická variace MeSH
- genotypizační techniky MeSH
- metagenomika * MeSH
- mikrobiální genetika MeSH
- polychlorované bifenyly analýza MeSH
- studie případů a kontrol MeSH
- Publikační typ
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
Metagenomics is gradually being implemented for diagnosing infectious diseases. However, in-depth protocol comparisons for viral detection have been limited to individual sets of experimental workflows and laboratories. In this study, we present a benchmark of metagenomics protocols used in clinical diagnostic laboratories initiated by the European Society for Clinical Virology (ESCV) Network on NGS (ENNGS). A mock viral reference panel was designed to mimic low biomass clinical specimens. The panel was used to assess the performance of twelve metagenomic wet lab protocols currently in use in the diagnostic laboratories of participating ENNGS member institutions. Both Illumina and Nanopore, shotgun and targeted capture probe protocols were included. Performance metrics sensitivity, specificity, and quantitative potential were assessed using a central bioinformatics pipeline. Overall, viral pathogens with loads down to 104 copies/ml (corresponding to CT values of 31 in our PCR assays) were detected by all the evaluated metagenomic wet lab protocols. In contrast, lower abundant mixed viruses of CT values of 35 and higher were detected only by a minority of the protocols. Considering the reference panel as the gold standard, optimal thresholds to define a positive result were determined per protocol, based on the horizontal genome coverage. Implementing these thresholds, sensitivity and specificity of the protocols ranged from 67 to 100 % and 87 to 100 %, respectively. A variety of metagenomic protocols are currently in use in clinical diagnostic laboratories. Detection of low abundant viral pathogens and mixed infections remains a challenge, implying the need for standardization of metagenomic analysis for use in clinical settings.
- MeSH
- benchmarking * MeSH
- lidé MeSH
- metagenomika * metody normy MeSH
- senzitivita a specificita * MeSH
- virové nemoci diagnóza virologie MeSH
- viry * genetika klasifikace izolace a purifikace MeSH
- výpočetní biologie metody MeSH
- vysoce účinné nukleotidové sekvenování metody normy MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
Understanding the relationship between gene diversity and function for important environmental processes is a major ecological research goal. We applied gene-targeted metagenomics and pyrosequencing to aromatic dioxygenase genes to obtain greater sequence depth than possible by other methods. A polymerase chain reaction (PCR) primer set designed to target a 524-bp region that confers substrate specificity of biphenyl dioxygenases yielded 2000 and 604 sequences from the 5' and 3' ends of PCR products, respectively, which passed our validity criteria. Sequence alignment showed three known conserved residues, as well as another seven conserved residues not reported earlier. Of the valid sequences, 95% and 41% were assigned to 22 and 3 novel clusters in that they did not include any earlier reported sequences at 0.6 distance by complete linkage clustering for sequenced regions. The greater diversity revealed by this gene-targeted approach provides deeper insights into genes potentially important in environmental processes to better understand their ecology, functional differences and evolutionary origins. We also provide criteria for primer design for this approach, as well as guidance for data processing of diverse functional genes, as gene databases for most genes of environmental relevance are limited.
- MeSH
- bakteriální geny * MeSH
- biodegradace MeSH
- dioxygenasy genetika metabolismus MeSH
- DNA primery genetika MeSH
- fylogeneze MeSH
- látky znečišťující půdu metabolismus MeSH
- metagenomika * MeSH
- polymerázová řetězová reakce MeSH
- půdní mikrobiologie * MeSH
- Publikační typ
- časopisecké články MeSH
- Research Support, N.I.H., Extramural MeSH
- Geografické názvy
- Česká republika MeSH
A phylogenetic tree at the species level is still far off for highly diverse insect orders, including the Coleoptera, but the taxonomic breadth of public sequence databases is growing. In addition, new types of data may contribute to increasing taxon coverage, such as metagenomic shotgun sequencing for assembly of mitogenomes from bulk specimen samples. The current study explores the application of these techniques for large-scale efforts to build the tree of Coleoptera. We used shotgun data from 17 different ecological and taxonomic datasets (5 unpublished) to assemble a total of 1942 mitogenome contigs of >3000 bp. These sequences were combined into a single dataset together with all mitochondrial data available at GenBank, in addition to nuclear markers widely used in molecular phylogenetics. The resulting matrix of nearly 16,000 species with two or more loci produced trees (RAxML) showing overall congruence with the Linnaean taxonomy at hierarchical levels from suborders to genera. We tested the role of full-length mitogenomes in stabilizing the tree from GenBank data, as mitogenomes might link terminals with non-overlapping gene representation. However, the mitogenome data were only partly useful in this respect, presumably because of the purely automated approach to assembly and gene delimitation, but improvements in future may be possible by using multiple assemblers and manual curation. In conclusion, the combination of data mining and metagenomic sequencing of bulk samples provided the largest phylogenetic tree of Coleoptera to date, which represents a summary of existing phylogenetic knowledge and a defensible tree of great utility, in particular for studies at the intra-familial level, despite some shortcomings for resolving basal nodes.
- MeSH
- algoritmy MeSH
- brouci klasifikace genetika MeSH
- databáze genetické MeSH
- fylogeneze * MeSH
- metagenomika * MeSH
- mitochondrie genetika MeSH
- sekvence nukleotidů MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Microbial colonization on the titanium condenser material (TCM) used in the cooling system leads to biofouling and corrosion and influences the water supply. The primary investigation of the titanium condenser was infrequently studied on characterizing biofilm-forming bacterial communities. Different treatment methods like electropotential charge, ultrasonication, and copper coating of titanium condenser material may influence the microbial population over the surface of the titanium condensers. The present study aimed to catalog the primary colonizers and the effect of different treatment methods on the microbial community. CFU (1.7 × 109 CFU/mL) and ATP count (< 5000 × 10-7 relative luminescence units) showed a minimal microbial population in copper-coated surface biofilm as compared with the other treatments. Live and dead cell result also showed consistency with colony count. The biofilm sample on the copper-coated surface showed an increased dead cell count and decreased live cells. In the metagenomic approach, the microbiome coverage was 10.06 Mb in samples derived from copper-coated TCM than in other treated samples (electropotential charge-17.94 Mb; ultrasonication-20.01 Mb), including control (10.18 Mb). Firmicutes preponderate the communities in the biofilm samples, and Proteobacteria stand next in the population in all the treated condenser materials. At the genus level, Lactobacillaceae and Azospirillaceae dominated the biofilm community. The metagenome data suggested that the attached community is different from those biofilm samples based on the environment that influences the bacterial community. The outcome of the present study depicts that copper coating was effective against biofouling and corrosion resistance of titanium condenser material for designing long-term durability.
Lower termites harbor in their hindgut complex microbial communities that are involved in the digestion of cellulose. Among these are protists, which are usually associated with specific bacterial symbionts found on their surface or inside their cells. While these form the foundations of a classic system in symbiosis research, we still know little about the functional basis for most of these relationships. Here, we describe the complex functional relationship between one protist, the oxymonad Streblomastix strix, and its ectosymbiotic bacterial community using single-cell genomics. We generated partial assemblies of the host S. strix genome and Candidatus Ordinivivax streblomastigis, as well as a complex metagenome assembly of at least 8 other Bacteroidetes bacteria confirmed by ribosomal (r)RNA fluorescence in situ hybridization (FISH) to be associated with S. strix. Our data suggest that S. strix is probably not involved in the cellulose digestion, but the bacterial community on its surface secretes a complex array of glycosyl hydrolases, providing them with the ability to degrade cellulose to monomers and fueling the metabolism of S. strix In addition, some of the bacteria can fix nitrogen and can theoretically provide S. strix with essential amino acids and cofactors, which the protist cannot synthesize. On the contrary, most of the bacterial symbionts lack the essential glycolytic enzyme enolase, which may be overcome by the exchange of intermediates with S. strix This study demonstrates the value of the combined single-cell (meta)genomic and FISH approach for studies of complicated symbiotic systems.
- MeSH
- analýza jednotlivých buněk metody MeSH
- Bacteria metabolismus MeSH
- Bacteroidetes genetika MeSH
- celulosa metabolismus MeSH
- Eukaryota metabolismus MeSH
- fylogeneze MeSH
- genom MeSH
- Isoptera genetika mikrobiologie MeSH
- metagenomika metody MeSH
- Oxymonadida metabolismus MeSH
- symbióza MeSH
- trávicí systém metabolismus MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
