scholarly journals The human gut archaeome: identification of diverse haloarchaea in Korean subjects

2020 ◽  
Author(s):  
Joon Yong Kim ◽  
Tae Woong Whon ◽  
Mi Young Lim ◽  
Yeon Bee Kim ◽  
Namhee Kim ◽  
...  

Abstract Background: Archaea are one of the least-studied members of the gut-dwelling autochthonous microbiota. Few studies have reported the dominance of methanogens in the archaeal microbiome (archaeome) of the human gut, although limited information regarding the diversity and abundance of other archaeal phylotypes is available.Results: We surveyed the archaeome of faecal samples collected from 897 East Asian subjects living in South Korea. In total, 42.47% faecal samples were positive for archaeal colonisation; these were subsequently subjected to archaeal 16S rRNA gene deep sequencing and real-time quantitative polymerase chain reaction-based abundance estimation. The mean archaeal relative abundance was 10.24% ± 4.58% of the total bacterial and archaeal abundance. We observed extensive colonisation of haloarchaea (95.54%) in the archaea-positive faecal samples, with 9.63% mean relative abundance in archaeal communities. Haloarchaea were relatively more abundant than methanogens in some samples. The presence of haloarchaea was also verified by fluorescence in situ hybridisation analysis. Owing to large inter-individual variations, we categorised the human gut archaeome into four archaeal enterotypes.Conclusions: The study demonstrated that the human gut archaeome is indigenous, responsive, and functional, expanding our understanding of the archaeal signature in the gut of human individuals.

2020 ◽  
Author(s):  
Joon Yong Kim ◽  
Tae Woong Whon ◽  
Mi Young Lim ◽  
Yeon Bee Kim ◽  
Namhee Kim ◽  
...  

Abstract Background Archaea are the least-studied members of the gut-dwelling autochthonous microbiota. Few studies have reported the exclusive dominance of methanogens in the archaeal microbiome (archaeome) of the human gut, although information regarding the diversity and abundance of other archaeal phylotypes is limited. Results We surveyed the archaeome in the faecal samples collected from 897 normal East Asian subjects living in South Korea. In total, 42.47% faecal samples were positive for archaeal colonization, which were subsequently subjected to archaeal 16S rRNA gene deep sequencing and abundance estimation. The mean archaeal abundance was 9.89 ± 4.48% of the total bacterial and archaeal abundance. We observed extensive colonization of haloarchaea (95.53%) in the Korean gut, with 9.63% mean relative abundance in archaeal communities. Haloarchaea were relatively more abundant than methanogens in certain samples. The presence of haloarchaea was also verified by fluorescence in situ hybridization analysis. Owing to large inter-individual variations, we categorized the human gut archaeome into four archaeal enterotypes. Conclusions The study demonstrated that the human gut archaeome is indigenous, responsive, and functional, expanding our understanding of the archaeal signature in the gut of normal healthy individuals.


BMC Cancer ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Lito E. Papanicolas ◽  
Sarah K. Sims ◽  
Steven L. Taylor ◽  
Sophie J. Miller ◽  
Christos S. Karapetis ◽  
...  

Abstract Background The gut microbiota influences many aspects of host physiology, including immune regulation, and is predictive of outcomes in cancer patients. However, whether conventional myelosuppressive chemotherapy affects the gut microbiota in humans with non-haematological malignancy, independent of antibiotic exposure, is unknown. Methods Faecal samples from 19 participants with non-haematological malignancy, who were receiving conventional chemotherapy regimens but not antibiotics, were examined prior to chemotherapy, 7–12 days after chemotherapy, and at the end of the first cycle of treatment. Gut microbiota diversity and composition was determined by 16S rRNA gene amplicon sequencing. Results Compared to pre-chemotherapy samples, samples collected 7–12 days following chemotherapy exhibited increased richness (mean 120 observed species ± SD 38 vs 134 ± 40; p = 0.007) and diversity (Shannon diversity: mean 6.4 ± 0.43 vs 6.6 ± 0.41; p = 0.02). Composition was significantly altered, with a significant decrease in the relative abundance of gram-positive bacteria in the phylum Firmicutes (pre-chemotherapy median relative abundance [IQR] 0.78 [0.11] vs 0.75 [0.11]; p = 0.003), and an increase in the relative abundance of gram-negative bacteria (Bacteroidetes: median [IQR] 0.16 [0.13] vs 0.21 [0.13]; p = 0.01 and Proteobacteria: 0.015 [0.018] vs 0.03 [0.03]; p = 0.02). Differences in microbiota characteristics from baseline were no longer significant at the end of the chemotherapy cycle. Conclusions Conventional chemotherapy results in significant changes in gut microbiota characteristics during the period of predicted myelosuppression post-chemotherapy. Further study is indicated to link microbiome changes during chemotherapy to clinical outcomes.


Forests ◽  
2019 ◽  
Vol 10 (7) ◽  
pp. 550 ◽  
Author(s):  
Huili Feng ◽  
Jiahuan Guo ◽  
Weifeng Wang ◽  
Xinzhang Song ◽  
Shuiqiang Yu

Understanding the composition and diversity of soil microorganisms that typically mediate the soil biogeochemical cycle is crucial for estimating greenhouse gas flux and mitigating global changes in plantation forests. Therefore, the objectives of this study were to investigate changes in diversity and relative abundance of bacteria and archaea with soil profiles and the potential factors influencing the vertical differentiation of microbial communities in a poplar plantation. We investigated soil bacterial and archaeal community compositions and diversities by 16S rRNA gene Illumina MiSeq sequencing at different depths of a poplar plantation forest in Chenwei forest farm, Sihong County, Jiangsu, China. More than 882,422 quality-filtered 16S rRNA gene sequences were obtained from 15 samples, corresponding to 34 classified phyla and 68 known classes. Ten major bacterial phyla and two archaeal phyla were found. The diversity of bacterial and archaeal communities decreased with depth of the plantation soil. Analysis of variance (ANOVA) of relative abundance of microbial communities exhibited that Nitrospirae, Verrucomicrobia, Latescibacteria, GAL15, SBR1093, and Euryarchaeota had significant differences at different depths. The transition zone of the community composition between the surface and subsurface occurred at 10–20 cm. Overall, our findings highlighted the importance of depth with regard to the complexity and diversity of microbial community composition in plantation forest soils.


2020 ◽  
Vol 79 (OCE2) ◽  
Author(s):  
Ilaria Carafa ◽  
Domenico Masuero ◽  
Urska Vrhovsek ◽  
Giovanni Bittante ◽  
Elena Franciosi ◽  
...  

AbstractConjugated linoleic acids (CLAs) show a number of putative health-promoting activities including anti-carcinogenic, anti-adipogenic, anti-diabetogenic, anti-inflammatory and antioxidant actions. CLAs are naturally produced by ruminal bacteria and several studies demonstrate that various lactobacilli and bifidobacteria are also able to produce CLAs in vitro from linoleic acid (LA). However, the ability of the human gut microbiota to produce CLA is less extensively studied. Our hypothesis is that the human gut microbiota is able to convert LA to CLA, and that the readily fermentable fiber inulin would positively modulate the growth of CLA-producing bacteria and, consequently increase the CLA content in the intestine.The capability of the faecal microbiota from five healthy donors to produce CLA was tested in anaerobic batch cultures for 48 hours at pH 5.5 and 6.5. Test treatments were linoleic acid (LA; 1 mg/mL) + bovine serum albumin (BSA; 0.2 mg/mL), and LA (1 mg/mL) + BSA (0.2 mg/mL) + inulin (1%, w/v) compared to a control BSA (0.2 mg/mL) fermentation. The microbial composition was analyzed 0, 24 and 48 hours after starting the fermentation by 16S rRNA gene Illumina MiSeq sequencing (V3-V4 region). CLAs were quantified by Ultra performance liquid chromatography - tandem mass spectrometer (UPLC-MS/MS) and bi-dimensional gas chromatography (GC x GC).The inclusion of LA + BSA + inulin at pH 5.5 significantly increased the relative abundance of Collinsella aerofaciens (p < 0.05), and tended to increase the relative abundance of bifidobacteria. LA + BSA + inulin at both pH 5.5 and 6.5 reduced the relative abundance of Parabacteroides, Bilophila, Clostridia and Enterobacteriaceae (p < 0.05). The concentration of CLA, in particular the isomer cis9,trans11 C18:2, was significantly higher in the LA + BSA + inulin group at pH 5.5 after 24 and 48 hours fermentation.The data show that the treatment LA + BSA + inulin at pH 5.5 induce substantial changes in microbiota composition, including bifidogenesis and CLA production in a human intestinal microbiota model. The changes of relative abundance detected are consistent with changes in gut bacteria previously linked to human health. Collinsella aerofaciens has been reported for reducing bloating, in particular in subjects suffering from irritable bowel syndrome, while Clostridia, Bilophila and Enterobacteriaceae causes human infections. In addition, the increase of bifidobacteria and LAB, which have previously been shown in vitro to produce CLA, may also be involved in CLA production under simulated cecal microbiome. These preclinical observations warrant confirmation in suitably designed animal and human mechanistic studies.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Telmo Blasco ◽  
Sergio Pérez-Burillo ◽  
Francesco Balzerani ◽  
Daniel Hinojosa-Nogueira ◽  
Alberto Lerma-Aguilera ◽  
...  

AbstractUnderstanding how diet and gut microbiota interact in the context of human health is a key question in personalized nutrition. Genome-scale metabolic networks and constraint-based modeling approaches are promising to systematically address this complex problem. However, when applied to nutritional questions, a major issue in existing reconstructions is the limited information about compounds in the diet that are metabolized by the gut microbiota. Here, we present AGREDA, an extended reconstruction of diet metabolism in the human gut microbiota. AGREDA adds the degradation pathways of 209 compounds present in the human diet, mainly phenolic compounds, a family of metabolites highly relevant for human health and nutrition. We show that AGREDA outperforms existing reconstructions in predicting diet-specific output metabolites from the gut microbiota. Using 16S rRNA gene sequencing data of faecal samples from Spanish children representing different clinical conditions, we illustrate the potential of AGREDA to establish relevant metabolic interactions between diet and gut microbiota.


2018 ◽  
Vol 2017 (2) ◽  
pp. 430-440 ◽  
Author(s):  
H. Abdelrahman ◽  
G. M. Islam ◽  
K. A. Gilbride

Abstract The activated sludge process in a wastewater treatment plant (WWTP) relies on the activity of microbes to reduce the organic and inorganic matter and produce effluent that is safe to discharge into receiving waters. This research examined the effects of the non-steroidal anti-inflammatory drug ibuprofen and the antibiotic tetracycline on the relative abundance and composition of eukaryotes and bacteria in the microbial population present in activated sludge from a WWTP. The current investigation was designed to observe the impact of these contaminants, at low (environmentally relevant concentrations) as well as high concentrations of the drugs. Using 16S and 18S rRNA gene primer sets and quantitative polymerase chain reaction, the abundance of each population was monitored as well as the relative ratio of the two populations under the various conditions. It was found that current environmentally relevant concentrations of ibuprofen (100 ng/mL) stimulated eukaryotic growth but higher concentrations (2,000 ng/mL, 100,000 ng/mL) reduced their numbers significantly especially in the presence of tetracycline. Finally using denaturing gradient gel electrophoresis, some of the more abundant eukaryotes were identified and it was noted that high ibuprofen and tetracycline concentrations favoured the abundance of some genera.


2015 ◽  
Vol 6 (3) ◽  
pp. 263-269 ◽  
Author(s):  
A.T. Bjerg ◽  
M.B. Sørensen ◽  
L. Krych ◽  
L.H. Hansen ◽  
A. Astrup ◽  
...  

Gut microbiota (GM) dysbiosis has been linked to obesity and its metabolic complications such as cardiovascular disease (CVD). The risk of developing CVD increases with elevated concentration of serum triacylglycerol (TAG). In a blinded, randomised two-arm parallel human intervention study we have previously found that four weeks of supplementation with Lactobacillus paracasei subsp. paracasei L. casei W8® (L. casei W8) compared to placebo reduced the concentration of TAG in 64 young healthy adults, an effect, likely mediated by a decreased stearoyl- CoA desaturase-1 (SCD1) activity. In the present study we analysed faecal samples obtained during the intervention study to investigate whether this effect was related to the ability of L. casei W8 to colonise the human gut after supplementation of L. casei W8 (1010 cfu daily) as determined by qPCR specific for L. paracasei and L. casei (L. casei group); whether L. casei W8 consumption affected GM composition as determined by 16S rRNA gene targeted 454/FLX amplicon sequencing; and whether these changes were associated with changes in TAG concentration and SCD1 activity. Faecal samples were collected at baseline, after four weeks supplementation and two weeks after the supplementation was ended, and fasting blood samples were collected at baseline and after 4 weeks. Four weeks supplementation with L. casei W8 did not affect the overall composition of the GM; however, an increase in the relative abundance of the L. casei group from 8.48×10−6% of the total GM compared to 2.83×10−3% at baseline (P<0.001) was observed. Two weeks after supplementation ended, the relative abundance of the L. casei group was still increased 14 times compared to before the intervention (P<0.01). However, neither the increase in the abundance of the L. casei group nor overall GM composition correlated with changes in blood lipids or SCD1 activity.


2019 ◽  
Author(s):  
Lei Liu ◽  
Qing Wang ◽  
Hongmei Qi ◽  
Ranjit Das ◽  
Huai Lin ◽  
...  

Abstract Background: Antibiotics are growing reported to cause human intestinal microbial disorders with increasing abundances of opportunistic pathogens, and fecal microbiota transplantation (FMT) has been confirmed to restore the dysbiosis of gut flora in many kinds of intestinal disease. However, to date, few studies have focused on the bloomed opportunistic pathogens associated human disease-related pathways as well as antibiotic resistance genes (ARGs) after vancomycin exposure, and there is limited information on using FMT for restoration of intestinal microbiome affected by antibiotics. Methods: This study investigated effects of vancomycin on the opportunistic pathogens, human disease-related pathways as well as ARGs in human gut, and the restoration of intestinal microbiome by FMT. Using the simulator of the human intestinal microbial ecosystem (SHIME), two reactors (representing the ascending and descending colon, respectively) were inoculated with human intestinal microbiota from a healthy adult volunteer who did not suffer from gastrointestinal diseases or take any antibiotic in the previous six months. Samples were collected from the reactors at six-time points (before treatment, after seven days of individual 10 mg/L, 100 mg/L, 1000 mg/L vancomycin treatment, 14 days following the termination of vancomycin and 14 days following FMT). The intestinal microbiome composition and function were analyzed using 16S rRNA gene sequencing and High-throughput Quantitative PCR (HT-qPCR).Results: Vancomycin treatment substantially increased human disease-related pathways and decreased abundances of ARGs. Besides, the bloomed opportunistic pathogens including Achromobacter, Klebsiella, and Pseudomonas, caused by vancomycin exposure, were positively correlated with human disease-related pathways. The microbiota abundance and genes of human disease-related pathways and antibiotic resistance showed a remarkable return towards baseline after FMT, but not for natural recovery. Conclusions: These findings suggest that impacts of vancomycin on human gut are profound and FMT will be a promising strategy in clinical application that can restore the dysbiosis of gut microbiota, which may be valuable for directing future work.


2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Xiao Bin Li ◽  
Xin Xin Huang ◽  
Chang Jiang Zang ◽  
Chen Ma ◽  
Kai Xu Chen ◽  
...  

Abstract Background There is little objective information concerning the effect of steam-flaked grains on foal’s growth performance and faecal microbiota. To determine the effects of steam-flaked grains on foal’s growth performance and faecal microbiota, faecal samples were collection from 18 foals which had been fed either corn, oat or barley diets over the 60 days of the experiment. Body weight and conformation measurements were collected. Next-generation sequencing of the V3 + V4 region of the 16 S rRNA gene was used to assess the microbial composition of faeces. Alpha diversity, Venn graph, Relative abundance and beta diversity are presented. Results There was a significantly higher larger increase in the body weight of those foals fed barley compared to either corn or oats. There were also significant changes in the Alpha diversity of the gut microbiota. The Shannon and Simpson indices were significantly higher in the barley fed group than those fed corn or oats. The Chao1 index was significantly higher in the oat fed group than the corn or barley fed groups. There were significant changes in the relative abundance of bacteria in the microbiota in terms of phylum, family and genus. The histogram of LDA value distribution showed that the 12 statistically different biomarkers of the bacteria were present. Tax4Fun function annotation clustering heat map showed that functional information was detected from 26 species of bacteria in faecal samples from the foals. Conclusions Differences by starch sources were found in overall growth of the foals and in the faecal microbiota if either supplementary corn, oat or barley was fed. Further studies are required to determine the potential impact of the changes in the microbiota on the health and development of foals fed cereal starch of different sources.


2021 ◽  
pp. 1-16
Author(s):  
Yu-Ming Huang ◽  
Daniel Straub ◽  
Andreas Kappler ◽  
Nicole Smith ◽  
Nia Blackwell ◽  
...  

Fe(II) oxidation coupled to nitrate reduction (NRFO) has been described for many environments. Yet very few autotrophic microorganisms catalysing NRFO have been cultivated and their diversity, as well as their mechanisms for NRFO <i>in situ</i> remain unclear. A novel autotrophic NRFO enrichment culture, named culture BP, was obtained from freshwater sediment. After more than 20 transfers, culture BP oxidized 8.22 mM of Fe(II) and reduced 2.42 mM of nitrate within 6.5 days under autotrophic conditions. We applied metagenomic, metatranscriptomic, and metaproteomic analyses to culture BP to identify the microorganisms involved in autotrophic NRFO and to unravel their metabolism. Overall, twelve metagenome-assembled genomes (MAGs) were constructed, including a dominant <i>Gallionellaceae</i> sp. MAG (≥71% relative abundance). Genes and transcripts associated with potential Fe(II) oxidizers in culture BP, identified as a <i>Gallionellaceae</i> sp., <i>Noviherbaspirillum</i> sp., and <i>Thiobacillus</i> sp., were likely involved in metal oxidation (e.g., <i>cyc2</i>, <i>mtoA</i>), denitrification (e.g., <i>nirK</i>/<i>S</i>, <i>norBC</i>), carbon fixation (e.g., <i>rbcL</i>), and oxidative phosphorylation. The putative Fe(II)-oxidizing protein Cyc2 was detected for the <i>Gallionellaceae</i> sp. Overall, a complex network of microbial interactions among several Fe(II) oxidizers and denitrifiers was deciphered in culture BP that might resemble NRFO mechanisms <i>in situ</i>. Furthermore, 16S rRNA gene amplicon sequencing from environmental samples revealed 36 distinct <i>Gallionellaceae</i> taxa, including the key player of NRFO from culture BP (approx. 0.13% relative abundance <i>in situ</i>). Since several of these <i>in situ</i>-detected <i>Gallionellaceae</i> taxa were closely related to the key player in culture BP, this suggests that the diversity of organisms contributing to NRFO might be higher than currently known.


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