Comparison of Microbial Populations in Saliva and Feces from Healthy and Celiac Adolescents with Conventional and Molecular Approaches after Cultivation on Gluten-Containing Media: An Exploratory Study

Microbes capable of metabolizing gluten are common in various parts of the intestinal tract. In this study, saliva and fecal samples were obtained from 10 adolescents (13–18 years of age), five of which had celiac disease (CD) and five of which were healthy volunteers (HV). Culture-enriched saliva and fecal samples were compared with molecular profiling, and microorganisms displaying lysis zones on gluten-containing media (i.e., gluten-degrading microorganisms; GDMs) were isolated. In total, 45 gluten-degrading strains were isolated, belonging to 13 genera and 15 species, including Candida albicans and Veillonella. GDMs were more common in HVs compared to CD patients and more diverse in saliva compared to feces. In saliva, GDMs showed partial overlap between HVs and CD patients. Bacterial communities in fecal samples determined with amplicon sequencing significantly differed between CD patients and HVs. Overall, 7–46 of all operational taxonomic units (OTUs) per sample were below the detection limit in the fecal samples but were present in the cultivated samples, and mainly included representatives from Lactobacillus and Enterococcus. Furthermore, differences in fecal short-chain fatty-acid concentrations between CD patients and HVs, as well as their correlations with bacterial taxa, were demonstrated.

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The Wheat Microbiome Under Four Management Strategies, and Potential for Endophytes in Disease Protection

Phytobiomes Journal ◽

10.1094/pbiomes-05-17-0023-r ◽

2017 ◽

Vol 1 (3) ◽

pp. 158-168 ◽

Cited By ~ 51

Author(s):

Kristi Gdanetz ◽

Frances Trail

Keyword(s):

Bacterial Communities ◽

Management Strategy ◽

Crop Yields ◽

Management Strategies ◽

Growing Season ◽

Amplicon Sequencing ◽

Antagonistic Activity ◽

Rrna Gene ◽

Operational Taxonomic Units ◽

Plant Organ

Manipulating plant-associated microbes to reduce disease or improve crop yields requires a thorough understanding of interactions within the phytobiome. Plants were sampled from a wheat/maize/soybean crop rotation site that implements four different crop management strategies. We analyzed the fungal and bacterial communities of leaves, stems, and roots of wheat throughout the growing season using 16S and fungal internal transcribed spacer 2 rRNA gene amplicon sequencing. The most prevalent operational taxonomic units (OTUs) were shared across all samples, although levels of the low-abundance OTUs varied. Endophytes were isolated from plants, and tested for antagonistic activity toward the wheat pathogen Fusarium graminearum. Antagonistic strains were assessed for plant protective activity in seedling assays. Our results suggest that microbial communities were strongly affected by plant organ and plant age, and may be influenced by management strategy.

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The effect of lactose and inulin on intestinal morphology, selected microbial populations and volatile fatty acid concentrations in the gastro-intestinal tract of the weanling pig

Animal Science ◽

10.1079/asc200634 ◽

2006 ◽

Vol 82 (3) ◽

pp. 311-318 ◽

Cited By ~ 57

Author(s):

K. M. Pierce ◽

T. Sweeney ◽

P. O. Brophy ◽

J. J. Callan ◽

E. Fitzpatrick ◽

...

Keyword(s):

Fatty Acid ◽

Volatile Fatty Acid ◽

Intestinal Tract ◽

Short Chain Fatty Acid ◽

Live Weight ◽

Intestinal Morphology ◽

Microbial Populations ◽

Tissue Samples ◽

Villous Height ◽

Gastro Intestinal Tract

AbstractTwenty piglets (21 days, 7·8 kg live weight (LW)) were used in a 2×2 factorial to investigate interactions between lactose and inulin on intestinal morphology, microbiology and volatile fatty acid (VFA) production of the weanling pig. The piglets were offered the following diets for 6 days and then sacrificed: (T1) 150 g/kg lactose, (T2) 150 g/kg lactose +15 g/kg inulin, ( T3) 330 g/kg lactose, and ( T4) 330 g/kg lactose +15 g/kg inulin. Tissue samples were taken from the duodenum, jejunum and ileum for morphological measurements. Digesta samples were taken from the ileum, caecum and colon. There was an interaction ( P<0·05) between lactose and inulin in villous height in the jejunum. The inclusion of inulin at 150 g/kg lactose increased villous height compared with 150 g/kg lactose without inulin. However, inulin had no effect on villous height at 330 g/kg lactose inclusion. There was a linear relationship between food intake and villous height in the duodenum (P<0·001, R2=0·45) and the jejunum (P< 0·01, R2=0·25). The inclusion of 330 g/kg lactose increased ( P<0·05) total VFA compared with 150 g/kg lactose in the caecum and the population of lactobacilli in the caecum and colon (P<0·1). There was an interaction (P<0·05) between lactose and inulin for total VFA concentration in the colon. The pigs receiving 330 g/kg lactose had a higher total VFA concentration compared with pigs on 150 g/kg lactose. However, there was no difference between 150 g/kg and 330 g/kg lactose when the diets were supplemented with inulin. In conclusion, the inclusion of high dietary concentrations of lactose resulted in increased lactobacilli and short-chain fatty acid concentrations. The inclusion of inulin with low dietary concentrations of lactose resulted in improved intestinal health through a reduction of intestinal pH and increases in villous height.

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Termites Are Associated with External Species-Specific Bacterial Communities

Applied and Environmental Microbiology ◽

10.1128/aem.02042-20 ◽

2020 ◽

Vol 87 (2) ◽

Author(s):

Patrik Soukup ◽

Tomáš Větrovský ◽

Petr Stiblik ◽

Kateřina Votýpková ◽

Amrita Chakraborty ◽

...

Keyword(s):

Bacterial Communities ◽

Amplicon Sequencing ◽

Rrna Gene ◽

Negative Effects ◽

Termite Species ◽

Positive Effects ◽

Operational Taxonomic Units ◽

Wide Range ◽

Species Specific ◽

And Control

ABSTRACT All termites have established a wide range of associations with symbiotic microbes in their guts. Some termite species are also associated with microbes that grow in their nests, but the prevalence of these associations remains largely unknown. Here, we studied the bacterial communities associated with the termites and galleries of three wood-feeding termite species by using 16S rRNA gene amplicon sequencing. We found that the compositions of bacterial communities among termite bodies, termite galleries, and control wood fragments devoid of termite activities differ in a species-specific manner. Termite galleries were enriched in bacterial operational taxonomic units (OTUs) belonging to Rhizobiales and Actinobacteria, which were often shared by several termite species. The abundance of several bacterial OTUs, such as Bacillus, Clostridium, Corynebacterium, and Staphylococcus, was reduced in termite galleries. Our results demonstrate that both termite guts and termite galleries harbor unique bacterial communities. IMPORTANCE As is the case for all ecosystem engineers, termites impact their habitat by their activities, potentially affecting bacterial communities. Here, we studied three wood-feeding termite species and found that they influence the composition of the bacterial communities in their surrounding environment. Termite activities have positive effects on Rhizobiales and Actinobacteria abundance and negative effects on the abundance of several ubiquitous genera, such as Bacillus, Clostridium, Corynebacterium, and Staphylococcus. Our results demonstrate that termite galleries harbor unique bacterial communities.

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Land Use Effects on Airborne Bacterial Communities Are Evident in Both Near-Surface and Higher-Altitude Air

Diversity ◽

10.3390/d13020085 ◽

2021 ◽

Vol 13 (2) ◽

pp. 85

Author(s):

Allison M. Spring ◽

Kenneth D. Domingue ◽

Thomas V. Kerber ◽

Margaret M. Mooney ◽

Rebecca L. Hale ◽

...

Keyword(s):

Land Use ◽

Bacterial Communities ◽

Amplicon Sequencing ◽

Small Scale ◽

Dispersal Patterns ◽

Near Surface ◽

Operational Taxonomic Units ◽

16S Rrna Amplicon Sequencing ◽

Surface Samples ◽

Land Use Effects

Land use influences the composition of near-surface airborne bacterial communities, and bacteria can be transported through the atmosphere at global scales. The atmosphere mixes vertically, but rigorously assessing whether the effects of land use on atmospheric communities extends to higher altitudes requires examining communities from multiple altitudes collected at a stable location and timeframe. In this study, we collected near-surface (<2 m) and higher-altitude (150 m) air samples from three sites in an agricultural/developed location and a forested/undeveloped location. We used bacterial 16S rRNA amplicon sequencing to compare communities and predict functionality by altitude. Higher-altitude and near-surface communities did not differ in composition within each location. Communities collected above the undeveloped location were equally variable at both altitudes; higher-altitude samples from the developed location predominantly contained Firmicutes and were less variable than near-surface samples. We also compared airborne taxa to those present in soil and snow. Communities from higher-altitude samples above the developed location contained fewer overlapping taxa with soil and snow sources, and overlapping Operational Taxonomic Units (OTUs) among the three sources differed by location. Our results suggest that land use affects the composition of both near-surface and higher-altitude airborne bacterial communities and, therefore, may influence broad bacterial dispersal patterns. This small-scale pilot study provides a framework for simultaneously examining local and regional airborne microbial communities that can be applied to larger studies or studies using different types of samplers.

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PSIX-25 Documenting succession of the rumen microbial community in dairy calves

Journal of Animal Science ◽

10.1093/jas/skaa278.588 ◽

2020 ◽

Vol 98 (Supplement_4) ◽

pp. 331-331

Author(s):

Courtney Deblois ◽

Garret Suen ◽

Kent Weigel ◽

Laura Hernandez ◽

Andrew Steinberger ◽

...

Keyword(s):

Amplicon Sequencing ◽

Dairy Calves ◽

Fecal Samples ◽

Operational Taxonomic Units ◽

Non Invasive ◽

Buccal Swabs ◽

Shared Otus ◽

Nutrient Provisioning ◽

Fully Functioning ◽

Accessible Form

Abstract Dairy cattle rely exclusively on the microbiota within their gastrointestinal tract for nutrient provisioning as they lack the endogenous enzymes needed to convert their plant-based diet into an accessible form. The acquisition of a fully functioning gut microbiome early in life is critical to survival of these animals. The establishment of a calf’s gut microbiota has previously been characterized using proxies such as fecal sampling and destructive sampling methods, but it is unclear how accurate these methods are over time in the same animals. To address this, 10 dairy calves were cannulated at 3 weeks of age. Rumen liquid and rumen solid samples were collected biweekly in congruence with buccal swabs and fecal samples from 7–17 weeks of age and characterized using Illumina 16S rRNA V4 amplicon sequencing. Fecal and buccal samples contained similar amounts of shared operational taxonomic units (OTUs) to the rumen pre-weaning but separated post-weaning such that buccal samples contained nearly double the number of shared OTUs. Beta diversity showed that fecal communities more closely resemble the rumen than buccal but shift as the animals begin ruminating such that buccal communities more closely resemble the rumen. This suggests that fecal samples would serve as a more accurate proxy prior to weaning whereas buccal samples would more accurately represent the rumen after weaning. These data will be invaluable for researchers interested in understanding the acquisition, succession, and establishment of the calf rumen microbiota using non-invasive approaches.

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New Insights on the Zeugodacus cucurbitae (Coquillett) Bacteriome

Microorganisms ◽

10.3390/microorganisms9030659 ◽

2021 ◽

Vol 9 (3) ◽

pp. 659

Author(s):

Elias Asimakis ◽

Panagiota Stathopoulou ◽

Apostolis Sapounas ◽

Kanjana Khaeso ◽

Costas Batargias ◽

...

Keyword(s):

Relative Abundance ◽

Bacterial Communities ◽

High Throughput Sequencing ◽

Mutual Exclusion ◽

Bacterial Composition ◽

Operational Taxonomic Units ◽

Host Diet ◽

Dominant Bacteria ◽

High Degree

Various factors, including the insect host, diet, and surrounding ecosystem can shape the structure of the bacterial communities of insects. We have employed next generation, high-throughput sequencing of the 16S rRNA to characterize the bacteriome of wild Zeugodacus (Bactrocera) cucurbitae (Coquillett) flies from three regions of Bangladesh. The tested populations developed distinct bacterial communities with differences in bacterial composition, suggesting that geography has an impact on the fly bacteriome. The dominant bacteria belonged to the families Enterobacteriaceae, Dysgomonadaceae and Orbaceae, with the genera Dysgonomonas, Orbus and Citrobacter showing the highest relative abundance across populations. Network analysis indicated variable interactions between operational taxonomic units (OTUs), with cases of mutual exclusion and copresence. Certain bacterial genera with high relative abundance were also characterized by a high degree of interactions. Interestingly, genera with a low relative abundance like Shimwellia, Gilliamella, and Chishuiella were among those that showed abundant interactions, suggesting that they are also important components of the bacterial community. Such knowledge could help us identify ideal wild populations for domestication in the context of the sterile insect technique or similar biotechnological methods. Further characterization of this bacterial diversity with transcriptomic and metabolic approaches, could also reveal their specific role in Z. cucurbitae physiology.

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Extremely Halophilic Biohydrogen Producing Microbial Communities from High-Salinity Soil and Salt Evaporation Pond

Fuels ◽

10.3390/fuels2020014 ◽

2021 ◽

Vol 2 (2) ◽

pp. 241-252

Author(s):

Dyah Asri Handayani Taroepratjeka ◽

Tsuyoshi Imai ◽

Prapaipid Chairattanamanokorn ◽

Alissara Reungsang

Keyword(s):

Microbial Communities ◽

High Throughput ◽

High Throughput Sequencing ◽

High Salinity ◽

Amplicon Sequencing ◽

Spatial Proximity ◽

Lignocellulosic Waste ◽

Evaporation Pond ◽

Operational Taxonomic Units ◽

Determining Factor

Extreme halophiles offer the advantage to save on the costs of sterilization and water for biohydrogen production from lignocellulosic waste after the pretreatment process with their ability to withstand extreme salt concentrations. This study identifies the dominant hydrogen-producing genera and species among the acclimatized, extremely halotolerant microbial communities taken from two salt-damaged soil locations in Khon Kaen and one location from the salt evaporation pond in Samut Sakhon, Thailand. The microbial communities’ V3–V4 regions of 16srRNA were analyzed using high-throughput amplicon sequencing. A total of 345 operational taxonomic units were obtained and the high-throughput sequencing confirmed that Firmicutes was the dominant phyla of the three communities. Halanaerobium fermentans and Halanaerobacter lacunarum were the dominant hydrogen-producing species of the communities. Spatial proximity was not found to be a determining factor for similarities between these extremely halophilic microbial communities. Through the study of the microbial communities, strategies can be developed to increase biohydrogen molar yield.

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Reversion of Gut Microbiota during the Recovery Phase in Patients with Asymptomatic or Mild COVID-19: Longitudinal Study

Microorganisms ◽

10.3390/microorganisms9061237 ◽

2021 ◽

Vol 9 (6) ◽

pp. 1237

Author(s):

Han-Na Kim ◽

Eun-Jeong Joo ◽

Chil-Woo Lee ◽

Kwang-Sung Ahn ◽

Hyung-Lae Kim ◽

...

Keyword(s):

Gut Microbiota ◽

Gastrointestinal Symptoms ◽

Amplicon Sequencing ◽

Recovery Phase ◽

Fecal Samples ◽

Intestinal Microbes ◽

Gut Dysbiosis ◽

16S Rrna Amplicon Sequencing ◽

Microbiome Data ◽

Negative Conversion

Patients with COVID-19 have been reported to experience gastrointestinal symptoms as well as respiratory symptoms, but the effects of COVID-19 on the gut microbiota are poorly understood. We explored gut microbiome profiles associated with the respiratory infection of SARS-CoV-2 during the recovery phase in patients with asymptomatic or mild COVID-19. A longitudinal analysis was performed using the same patients to determine whether the gut microbiota changed after recovery from COVID-19. We applied 16S rRNA amplicon sequencing to analyze two paired fecal samples from 12 patients with asymptomatic or mild COVID-19. Fecal samples were selected at two time points: during SARS-CoV-2 infection (infected state) and after negative conversion of the viral RNA (recovered state). We also compared the microbiome data with those from 36 healthy controls. Microbial evenness of the recovered state was significantly increased compared with the infected state. SARS-CoV-2 infection induced the depletion of Bacteroidetes, while an abundance was observed with a tendency to rapidly reverse in the recovered state. The Firmicutes/Bacteroidetes ratio in the infected state was markedly higher than that in the recovered state. Gut dysbiosis was observed after infection even in patients with asymptomatic or mild COVID-19, while the composition of the gut microbiota was recovered after negative conversion of SARS-CoV-2 RNA. Modifying intestinal microbes in response to COVID-19 might be a useful therapeutic alternative.

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Handling of spurious sequences affects the outcome of high-throughput 16S rRNA gene amplicon profiling

ISME Communications ◽

10.1038/s43705-021-00033-z ◽

2021 ◽

Vol 1 (1) ◽

Author(s):

Sandra Reitmeier ◽

Thomas C. A. Hitch ◽

Nicole Treichel ◽

Nikolaos Fikas ◽

Bela Hausmann ◽

...

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Amplicon Sequencing ◽

Rrna Gene ◽

Diversity Analysis ◽

Careful Attention ◽

Operational Taxonomic Units ◽

Basic Concepts ◽

Gnotobiotic Mice ◽

Mock Communities

Abstract16S rRNA gene amplicon sequencing is a popular approach for studying microbiomes. However, some basic concepts have still not been investigated comprehensively. We studied the occurrence of spurious sequences using defined microbial communities based on data either from the literature or generated in three sequencing facilities and analyzed via both operational taxonomic units (OTUs) and amplicon sequence variants (ASVs) approaches. OTU clustering and singleton removal, a commonly used approach, delivered approximately 50% (mock communities) to 80% (gnotobiotic mice) spurious taxa. The fraction of spurious taxa was generally lower based on ASV analysis, but varied depending on the gene region targeted and the barcoding system used. A relative abundance of 0.25% was found as an effective threshold below which the analysis of spurious taxa can be prevented to a large extent in both OTU- and ASV-based analysis approaches. Using this cutoff improved the reproducibility of analysis, i.e., variation in richness estimates was reduced by 38% compared with singleton filtering using six human fecal samples across seven sequencing runs. Beta-diversity analysis of human fecal communities was markedly affected by both the filtering strategy and the type of phylogenetic distances used for comparison, highlighting the importance of carefully analyzing data before drawing conclusions on microbiome changes. In summary, handling of artifact sequences during bioinformatic processing of 16S rRNA gene amplicon data requires careful attention to avoid the generation of misleading findings. We propose the concept of effective richness to facilitate the comparison of alpha-diversity across studies.

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