Search results for "METAGENOMIC"
showing 10 items of 177 documents
Ecological and genomic features of two widespread freshwater picocyanobacteria
2018
We present two genomes of widespread freshwater picocyanobacteria isolated by extinction dilution from a Spanish oligotrophic reservoir. Based on microscopy and genomic properties, both picocyanobacteria were tentatively designated Synechococcus lacustris Tous, formerly described as a metagenome assembled genome (MAG) from the same habitat, and Cyanobium usitatum Tous, described here for the first time. Both strains were purified in unicyanobacterial cultures, and their genomes were sequenced. They are broadly distributed in freshwater systems; the first seems to be a specialist on temperate reservoirs (Tous, Amadorio, Dexter, Lake Lanier, Sparkling), and the second appears to also be abund…
Understanding the microbial biogeography of ancient human dentitions to guide study design and interpretation
2021
AbstractThe oral cavity is a heterogeneous environment, varying in factors such as pH, oxygen levels, and salivary flow. These factors affect the microbial community composition and distribution of species in dental plaque, but it is not known how well these patterns are reflected in archaeological dental calculus. In most archaeological studies, a single sample of dental calculus is studied per individual and is assumed to represent the entire oral cavity. However, it is not known if this sampling strategy introduces biases into studies of the ancient oral microbiome. Here, we present the results of a shotgun metagenomic study of a dense sampling of dental calculus from four Chalcolithic i…
Different Medicago truncatula genotypes, expressing different phenotypes, modulate microbial functional genes in the rhizosphere
2022
Plants host in their rhizosphere a remarkable diversity of microorganisms that in return promote plant growth and health. Thus, the plant microbiota emerges as a novel component that expand the capacity of plants to adapt to the environment, and thus pave the way for future breeding approaches.It is widely known that different plant species harbor different microbiota, but very few studies showed an impact of the plant genotypes on the microbiota. These contrasting results may depend on the choice of the tested genotypes.We formulate the hypothesis that only those plant genotypes showing high genetic diversity and expressing different phenotypes harbor different rhizosphere microbiota and a…
ANALISI DELLA COMUNITÀ MICROBICA INTESTINALE DI Reculitermes lucifugus (ROSSI) (ISOPTERA: RHINOTERMITIDAE)
2012
Reticulitermes lucifugus è una specie di termite diffusa in Italia e che causa gravi danni alle strutture legnose di monumenti storici e artistici. L’intestino delle termiti ospita una comunità microbica di batteri e flagellati, responsabile della degradazione del materiale lignocellulosico. Studi preliminari sulla comunità microbica dei simbionti di R. lucifugus, hanno descritto alcune specie di protozoi, ma non ci sono ancora informazioni sui simbionti batterici. Al fine di caratterizzare la comunità microbica intestinale di R. lucifugus è stato utilizzato un approccio molecolare coltura indipendente e colture di arricchimento per l’isolamento dei batteri cellulosolitici. Per l’analisi co…
Key roles for freshwater A ctinobacteria revealed by deep metagenomic sequencing
2014
Freshwater ecosystems are critical but fragile environments directly affecting society and its welfare. However, our understanding of genuinely freshwater microbial communities, constrained by our capacity to manipulate its prokaryotic participants in axenic cultures, remains very rudimentary. Even the most abundant components, freshwater Actinobacteria, remain largely unknown. Here, applying deep metagenomic sequencing to the microbial community of a freshwater reservoir, we were able to circumvent this traditional bottleneck and reconstruct de novo seven distinct streamlined actinobacterial genomes. These genomes represent three new groups of photoheterotrophic, planktonic Actinobacteria.…
Microbiome: pro-inflammatory Prevotella?
2013
Rheumatoid arthritis (RA) is a prevalent systemic autoimmune disease, caused by a combination of genetic and environmental factors. Animal models suggest a role for intestinal bacteria in supporting the systemic immune response required for joint inflammation. Here we performed 16S sequencing on 114 stool samples from rheumatoid arthritis patients and controls, and shotgun sequencing on a subset of 44 such samples. We identified the presence of Prevotella copri as strongly correlated with disease in new-onset untreated rheumatoid arthritis (NORA) patients. Increases in Prevotella abundance correlated with a reduction in Bacteroides and a loss of reportedly beneficial microbes in NORA subjec…
Beyond cells – The virome in the human holobiont
2019
Viromics, or viral metagenomics, is a relatively new and burgeoning field of research that studies the complete collection of viruses forming part of the microbiota in any given niche. It has strong foundations rooted in over a century of discoveries in the field of virology and recent advances in molecular biology and sequencing technologies. Historically, most studies have deconstructed the concept of viruses into a simplified perception of viral agents as mere pathogens, which demerits the scope of large-scale viromic analyses. Viruses are, in fact, much more than regular parasites. They are by far the most dynamic and abundant entity and the greatest killers on the planet, as well as th…
PVAmpliconFinder: a workflow for the identification of human papillomaviruses from high-throughput amplicon sequencing
2019
Abstract Background The detection of known human papillomaviruses (PVs) from targeted wet-lab approaches has traditionally used PCR-based methods coupled with Sanger sequencing. With the introduction of next-generation sequencing (NGS), these approaches can be revisited to integrate the sequencing power of NGS. Although computational tools have been developed for metagenomic approaches to search for known or novel viruses in NGS data, no appropriate tool is available for the classification and identification of novel viral sequences from data produced by amplicon-based methods. Results We have developed PVAmpliconFinder, a data analysis workflow designed to rapidly identify and classify kno…
A New Method for Extracting Skin Microbes Allows Metagenomic Analysis of Whole-Deep Skin
2013
In the last decade, an extensive effort has been made to characterize the human microbiota, due to its clinical and economic interests. However, a metagenomic approach to the skin microbiota is hampered by the high proportion of host DNA that is recovered. In contrast with the burgeoning field of gut metagenomics, skin metagenomics has been hindered by the absence of an efficient method to avoid sequencing the host DNA. We present here a method for recovering microbial DNA from skin samples, based on a combination of molecular techniques. We have applied this method to mouse skin, and have validated it by standard, quantitative PCR and amplicon sequencing of 16S rRNA. The taxonomic diversit…
Microbial Diversity in the Midguts of Field and Lab-Reared Populations of the European Corn Borer Ostrinia nubilalis
2011
Background: Insects are associated with microorganisms that contribute to the digestion and processing of nutrients. The European Corn Borer (ECB) is a moth present world-wide, causing severe economical damage as a pest on corn and other crops. In the present work, we give a detailed view of the complexity of the microorganisms forming the ECB midgut microbiota with the objective of comparing the biodiversity of the midgut-associated microbiota and explore their potential as a source of genes and enzymes with biotechnological applications. Methodological/Principal Findings: A high-throughput sequencing approach has been used to identify bacterial species, genes and metabolic pathways, parti…