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1.
Biodivers Data J ; 12: e119481, 2024.
Article in English | MEDLINE | ID: mdl-38524899

ABSTRACT

Background: The genus Clavicornaltica Scherer 1974 consists of very small, soil-dwelling flea beetles in South, Southeast and East Asia. Due to their diminutive size and morphological similarities, very little is known about their ecology and taxonomical diversity. It is likely that further studies will reveal this genus to be much more speciose than the 30 species currently recognised. New information: A new species of Clavicornaltica from Brunei Darussalam is described, C.mataikanensis Otani et al., sp. nov. This is the second species of this genus recorded from Ulu Temburong National Park.

2.
mSystems ; 8(4): e0124922, 2023 08 31.
Article in English | MEDLINE | ID: mdl-37427928

ABSTRACT

In vitro studies of synthetic gut microbial communities (SGMCs) can provide valuable insights into the ecological structure and function of gut microbiota. However, the importance of the quantitative composition of an SGMC inoculum and its effect on the eventual stable in vitro microbial community has not been studied. To address this, we constructed two 114-member SGMCs differing only in their quantitative composition-one reflecting the average human fecal microbiome and another mixed in equal proportions based on cell counts. We inoculated each in an automated anaerobic multi-stage in vitro gut fermentor simulating two different colonic conditions, mimicking proximal and distal colons. We replicated this setup with two different nutrient media, periodically sampled the cultures for 27 days, and profiled their microbiome compositions using 16S rRNA gene amplicon sequencing. While nutrient medium explained 36% of the variance in microbiome composition, initial inoculum composition failed to show a statistically significant effect. Under all four conditions, paired fecal and equal SGMC inoculums converged to reach stable community compositions resembling each other. Our results have broad implications for simplifying in vitro SGMC investigations. IMPORTANCE In vitro cultivation of synthetic gut microbial communities (SGMCs) can provide valuable insights into the ecological structure and function of gut microbiota. However, it is currently not known whether the quantitative composition of the initial inoculum can influence the eventual stable in vitro community structure. Hence, using two SGMC inoculums consisting of 114 unique species mixed in either equal proportions (Eq inoculum) or resembling proportions in an average human fecal microbiome (Fec inoculum), we show that initial inoculum compositions did not influence the final stable community structure in a multi-stage in vitro gut fermentor. Under two different nutrient media and two different colon conditions (proximal and distal), both Fec and Eq communities converged to resemble each other's community structure. Our results suggest that the time-consuming preparation of SGMC inoculums may not be needed and has broad implications for in vitro SGMC studies.


Subject(s)
Gastrointestinal Microbiome , Microbiota , Humans , Gastrointestinal Microbiome/genetics , RNA, Ribosomal, 16S/genetics , Feces , Bioreactors
3.
Front Bioinform ; 2: 846922, 2022.
Article in English | MEDLINE | ID: mdl-36304282

ABSTRACT

Omics technologies have revolutionized microbiome research allowing the characterization of complex microbial communities in different biomes without requiring their cultivation. As a consequence, there has been a great increase in the generation of omics data from metagenomes and metatranscriptomes. However, pre-processing and analysis of these data have been limited by the availability of computational resources, bioinformatics expertise and standardized computational workflows to obtain consistent results that are comparable across different studies. Here, we introduce MIntO (Microbiome Integrated meta-Omics), a highly versatile pipeline that integrates metagenomic and metatranscriptomic data in a scalable way. The distinctive feature of this pipeline is the computation of gene expression profile through integrating metagenomic and metatranscriptomic data taking into account the community turnover and gene expression variations to disentangle the mechanisms that shape the metatranscriptome across time and between conditions. The modular design of MIntO enables users to run the pipeline using three available modes based on the input data and the experimental design, including de novo assembly leading to metagenome-assembled genomes. The integrated pipeline will be relevant to provide unique biochemical insights into microbial ecology by linking functions to retrieved genomes and to examine gene expression variation. Functional characterization of community members will be crucial to increase our knowledge of the microbiome's contribution to human health and environment. MIntO v1.0.1 is available at https://github.com/arumugamlab/MIntO.

4.
Genome Biol ; 22(1): 209, 2021 07 14.
Article in English | MEDLINE | ID: mdl-34261503

ABSTRACT

BACKGROUND: Akkermansia muciniphila is a human gut microbe with a key role in the physiology of the intestinal mucus layer and reported associations with decreased body mass and increased gut barrier function and health. Despite its biomedical relevance, the genomic diversity of A. muciniphila remains understudied and that of closely related species, except for A. glycaniphila, unexplored. RESULTS: We present a large-scale population genomics analysis of the Akkermansia genus using 188 isolate genomes and 2226 genomes assembled from 18,600 metagenomes from humans and other animals. While we do not detect A. glycaniphila, the Akkermansia strains in the human gut can be grouped into five distinct candidate species, including A. muciniphila, that show remarkable whole-genome divergence despite surprisingly similar 16S rRNA gene sequences. These candidate species are likely human-specific, as they are detected in mice and non-human primates almost exclusively when kept in captivity. In humans, Akkermansia candidate species display ecological co-exclusion, diversified functional capabilities, and distinct patterns of associations with host body mass. Analysis of CRISPR-Cas loci reveals new variants and spacers targeting newly discovered putative bacteriophages. Remarkably, we observe an increased relative abundance of Akkermansia when cognate predicted bacteriophages are present, suggesting ecological interactions. A. muciniphila further exhibits subspecies-level genetic stratification with associated functional differences such as a putative exo/lipopolysaccharide operon. CONCLUSIONS: We uncover a large phylogenetic and functional diversity of the Akkermansia genus in humans. This variability should be considered in the ongoing experimental and metagenomic efforts to characterize the health-associated properties of A. muciniphila and related bacteria.


Subject(s)
Gastrointestinal Microbiome/genetics , Genome, Bacterial , Metagenome , Phylogeny , Akkermansia/classification , Akkermansia/genetics , Akkermansia/metabolism , Akkermansia/virology , Animals , Bacteriophages/growth & development , Clustered Regularly Interspaced Short Palindromic Repeats , Genetic Variation , Humans , Mice , Operon , RNA, Ribosomal, 16S/genetics
5.
Genome Biol ; 20(1): 299, 2019 12 28.
Article in English | MEDLINE | ID: mdl-31883524

ABSTRACT

BACKGROUND: Humans have coevolved with microbial communities to establish a mutually advantageous relationship that is still poorly characterized and can provide a better understanding of the human microbiome. Comparative metagenomic analysis of human and non-human primate (NHP) microbiomes offers a promising approach to study this symbiosis. Very few microbial species have been characterized in NHP microbiomes due to their poor representation in the available cataloged microbial diversity, thus limiting the potential of such comparative approaches. RESULTS: We reconstruct over 1000 previously uncharacterized microbial species from 6 available NHP metagenomic cohorts, resulting in an increase of the mappable fraction of metagenomic reads by 600%. These novel species highlight that almost 90% of the microbial diversity associated with NHPs has been overlooked. Comparative analysis of this new catalog of taxa with the collection of over 150,000 genomes from human metagenomes points at a limited species-level overlap, with only 20% of microbial candidate species in NHPs also found in the human microbiome. This overlap occurs mainly between NHPs and non-Westernized human populations and NHPs living in captivity, suggesting that host lifestyle plays a role comparable to host speciation in shaping the primate intestinal microbiome. Several NHP-specific species are phylogenetically related to human-associated microbes, such as Elusimicrobia and Treponema, and could be the consequence of host-dependent evolutionary trajectories. CONCLUSIONS: The newly reconstructed species greatly expand the microbial diversity associated with NHPs, thus enabling better interrogation of the primate microbiome and empowering in-depth human and non-human comparative and co-diversification studies.


Subject(s)
Gastrointestinal Microbiome , Metagenome , Primates/microbiology , Animals , Humans , Phylogeny , Treponema/genetics
6.
Oncol. clín ; 18(1): 21-23, mar. 2013. ilus
Article in Spanish | LILACS | ID: biblio-835099

ABSTRACT

El carcinoma suprarrenal es una enfermedad infrecuente que afecta entre 0.45 a 2 personas cada millón. Relación mujer: hombre 2.7:1, con un promedio de edad de 45 años. Mayor compromiso de la glándula izquierda. En el 53% de los casos se diagnostica por síndromes funcionantes. El resto se expresa por efecto de masa o por detección de metástasis. Son fundamentales las imágenes y el testeo hormonal. Es muy agresivo, de mal pronóstico y generalmente avanzado al diagnóstico. A la fecha existen escasos recursos terapéuticos. A continuación, se presenta una paciente de 23 años con un cáncer de suprarrenal funcionante estadio IV.


The adrenal carcinoma is an infrequent disease that affects0.45 to 2 cases per millon population per year. Women aremore frequently affected than men (2.7:1), with an averageage of 45 years. More common is the commitment of theleft gland. In 53% of cases, functioning tumor exists. Therest are diagnosed from local tumour invasion. Images andhormonal laboratory are basic. It is very aggressive, withpoor prognosis and advanced at diagnosis. To date thereare few therapeutic resources. We present here a 23 yearsold patient with such diagnosis and metastatic stage.


Subject(s)
Humans , Adrenal Glands , Carcinoma , Cushing Syndrome , Acanthosis Nigricans , Acne Vulgaris , Hirsutism , Mitotane , Neoplasm Metastasis
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