Metagenomic sequencing reveals altered gut microbiota of sojourners at high altitude: a longitudinal study

Brij Bhushan ◽  
M. R. Eslavath ◽  
A. P. Yadav ◽  
A. K. Srivastava ◽  
M. P. K. Reddy ◽  
2021 ◽  
Vol 11 (1) ◽  
Francesco Durazzi ◽  
Claudia Sala ◽  
Gastone Castellani ◽  
Gerardo Manfreda ◽  
Daniel Remondini ◽  

AbstractIn this paper we compared taxonomic results obtained by metataxonomics (16S rRNA gene sequencing) and metagenomics (whole shotgun metagenomic sequencing) to investigate their reliability for bacteria profiling, studying the chicken gut as a model system. The experimental conditions included two compartments of gastrointestinal tracts and two sampling times. We compared the relative abundance distributions obtained with the two sequencing strategies and then tested their capability to distinguish the experimental conditions. The results showed that 16S rRNA gene sequencing detects only part of the gut microbiota community revealed by shotgun sequencing. Specifically, when a sufficient number of reads is available, Shotgun sequencing has more power to identify less abundant taxa than 16S sequencing. Finally, we showed that the less abundant genera detected only by shotgun sequencing are biologically meaningful, being able to discriminate between the experimental conditions as much as the more abundant genera detected by both sequencing strategies.

2017 ◽  
Vol 312 (4) ◽  
pp. G327-G339 ◽  
Rebecca L. Knoll ◽  
Kristoffer Forslund ◽  
Jens Roat Kultima ◽  
Claudius U. Meyer ◽  
Ulrike Kullmer ◽  

Current treatment for pediatric inflammatory bowel disease (IBD) patients is often ineffective, with serious side effects. Manipulating the gut microbiota via fecal microbiota transplantation (FMT) is an emerging treatment approach but remains controversial. We aimed to assess the composition of the fecal microbiome through a comparison of pediatric IBD patients to their healthy siblings, evaluating risks and prospects for FMT in this setting. A case-control (sibling) study was conducted analyzing fecal samples of six children with Crohn’s disease (CD), six children with ulcerative colitis (UC) and 12 healthy siblings by metagenomic sequencing. In addition, lifetime antibiotic intake was retrospectively determined. Species richness and diversity were significantly reduced in UC patients compared with control [Mann-Whitney U-test false discovery rate (MWU FDR) = 0.011]. In UC, bacteria positively influencing gut homeostasis, e.g., Eubacterium rectale and Faecalibacterium prausnitzii, were significantly reduced in abundance (MWU FDR = 0.05). Known pathobionts like Escherichia coli were enriched in UC patients (MWU FDR = 0.084). Moreover, E. coli abundance correlated positively with that of several virulence genes (SCC > 0.65, FDR < 0.1). A shift toward antibiotic-resistant taxa in both IBD groups distinguished them from controls [MWU Benjamini-Hochberg-Yekutieli procedure (BY) FDR = 0.062 in UC, MWU BY FDR = 0.019 in CD). The collected results confirm a microbial dysbiosis in pediatric UC, and to a lesser extent in CD patients, replicating associations found previously using different methods. Taken together, these observations suggest microbiotal remodeling therapy from family donors, at least for children with UC, as a viable option. NEW & NOTEWORTHY In this sibling study, prior reports of microbial dysbiosis in IBD patients from 16S rRNA sequencing was verified using deep shotgun sequencing and augmented with insights into the abundance of bacterial virulence genes and bacterial antibiotic resistance determinants, seen against the background of data on the specific antibiotic intake of each of the study participants. The observed dysbiosis, which distinguishes patients from siblings, highlights such siblings as potential donors for microbiotal remodeling therapy in IBD.

2021 ◽  
Vol 12 ◽  
Wei Song ◽  
Li-Ying Sun ◽  
Zhi-Jun Zhu ◽  
Lin Wei ◽  
Wei Qu ◽  

Background and AimsBiliary atresia (BA) is an idiopathic neonatal cholestasis and is the most common indication in pediatric liver transplantation (LT). Previous studies have suggested that the gut microbiota (GM) in BA is disordered. However, the effect of LT on gut dysbiosis in patients with BA has not yet been elucidated.MethodsPatients with BA (n = 16) and healthy controls (n = 10) were recruited. In the early life of children with BA, Kasai surgery is a typical procedure for restoring bile flow. According to whether BA patients had previously undergone Kasai surgery, we divided the post-LT patients into the with-Kasai group (n = 8) and non-Kasai group (n = 8). Fecal samples were collected in both the BA and the control group; among BA patients, samples were obtained again 6 months after LT. A total of 40 fecal samples were collected, of which 16 were pre-LT, 14 were post-LT (8 were with-Kasai, 6 were non-Kasai), and 10 were from the control group. Metagenomic sequencing was performed to evaluate the GM.ResultsThe Kruskal-Wallis test showed a statistically significant difference in the number of genes between the pre-LT and the control group, the pre-LT and the post-LT group (P &lt; 0.05), but no statistical difference between the post-LT and the control group. Principal coordinate analysis also showed that the microbiome structure was similar between the post-LT and control group (P &gt; 0.05). Analysis of the GM composition showed a significant decrease in Serratia, Enterobacter, Morganella, Skunalikevirus, and Phifllikevirus while short chain fatty acid (SCFA)-producing bacteria such as Roseburia, Blautia, Clostridium, Akkermansia, and Ruminococcus were increased after LT (linear discriminant analysis &gt; 2, P &lt; 0.05). However, they still did not reach the normal control level. Concerning functional profiles, lipopolysaccharide metabolism, multidrug resistance, polyamine biosynthesis, GABA biosynthesis, and EHEC/EPEC pathogenicity signature were more enriched in the post-LT group compared with the control group. Prior Kasai surgery had a specific influence on the postoperative GM.ConclusionLT partly improved the GM in patients with BA, which provided new insight into understanding the role of LT in BA.

2019 ◽  
Feng Zhu ◽  
Yanmei Ju ◽  
Wei Wang ◽  
Qi Wang ◽  
Ruijin Guo ◽  

AbstractEmerging evidence has linked the gut microbiota to schizophrenia. However, the functional changes in the gut microbiota and the biological role of individual bacterial species in schizophrenia have not been explored systematically. Here, we characterized the gut microbiota in schizophrenia using shotgun metagenomic sequencing of feces from a discovery cohort of 90 drug-free patients and 81 controls, as well as a validation cohort of 45 patients taking antipsychotics and 45 controls. We screened 83 schizophrenia-associated bacterial species and constructed a classifier comprising 26 microbial biomarkers that distinguished patients from controls with a 0.896 area under the receiver operating characteristics curve (AUC) in the discovery cohort and 0.765 AUC in the validation cohort. Our analysis of fecal metagenomes revealed that schizophrenia-associated gut–brain modules included short-chain fatty acids synthesis, tryptophan metabolism, and synthesis/degradation of neurotransmitters including glutamate, γ-aminobutyric acid, and nitric oxide. The schizophrenia-enriched gut bacterial species include several oral cavity-resident microbes, such as Streptococcus vestibularis. We transplanted Streptococcus vestibularis into the gut of the mice with antibiotic-induced microbiota depletion to explore its functional role. We observed that this microbe transiently inhabited the mouse gut and this was followed by hyperactivity and deficit in social behaviors, accompanied with altered neurotransmitter levels in peripheral tissues. In conclusion, our study identified 26 schizophrenia-associated bacterial species representing potential microbial targets for future treatment, as well as gut–brain modules, some of which may give rise to new microbial metabolites involved in the development of schizophrenia.

2021 ◽  
Elizabeth Fleming ◽  
Victor Pabst ◽  
Amelia Hoyt ◽  
Wei Zhou ◽  
Rachel Hardy ◽  

Genomics-driven discovery of microbial species have provided extraordinary insights into the biodiversity of human microbiota. High resolution genomics to investigate species- and strain-level diversity and mechanistic studies, however, rely on the availability of individual microbes from a complex microbial consortia. Here, we describe and validate a streamlined workflow for cultivating microbes from the skin, oral, and gut microbiota, informed by metagenomic sequencing, mass spectrometry, and strain profiling.

2020 ◽  
Caroline Ivanne Le Roy ◽  
Alexander Kurilshikov ◽  
Emily Leeming ◽  
Alessia Visconti ◽  
Ruth Bowyer ◽  

Abstract Background: Yoghurt contains live bacteria that could contribute via modulation of the gut microbiota to its reported beneficial effects such as reduced body weight gain and lower incidence of type 2 diabetes. To date, the association between yoghurt consumption and the composition of the gut microbiota is underexplored. Here we used clinical variables, metabolomics, 16S rRNA and shotgun metagenomic sequencing data collected on over 1000 predominantly female UK twins to define the link between the gut microbiota and yoghurt-associated health benefits. Results: According to food frequency questionnaires (FFQ), 73% of subjects consumed yoghurt. Consumers presented a healthier diet pattern (healthy eating index: beta = 2.17±0.34; P = 2.72x10-10) and improved metabolic health characterised by reduced visceral fat (beta = -28.18±11.71 g; P = 0.01). According to 16S rRNA gene analyses and whole shotgun metagenomic sequencing approach consistent taxonomic variations were observed with yoghurt consumption. More specifically, we identified higher abundance of species used as yoghurt starters Streptococcus thermophilus (beta = 0.41±0.051; P = 6.14x10-12) and sometimes added Bifidobacterium animalis subsp. lactis (beta = 0.30±0.052; P = 1.49x10-8) in the gut of yoghurt consumers. Replication in 1103 volunteers from the LifeLines-DEEP cohort confirmed the increase of S. thermophilus among yoghurt consumers. Using food records collected the day prior to faecal sampling we showed that increase in these two yoghurt bacteria could be transient. Metabolomics analysis revealed that B. animalis subsp. lactis was associated with 13 faecal metabolites including a 3-hydroxyoctanoic acid, known to be involved in the regulation of gut inflammation.Conclusions: Yoghurt consumption is associated with reduced visceral fat mass and changes in gut microbiome including transient increase of yoghurt-contained species (i.e. S. thermophilus and B. lactis).

2019 ◽  
Vol 516 (1) ◽  
pp. 120-126 ◽  
Yan Ma ◽  
Shuang Ma ◽  
Lan Chang ◽  
Haijie Wang ◽  
Qin Ga ◽  

2020 ◽  
Vol 79 (OCE2) ◽  
Anna M. Malinowska ◽  
Marcin Schmidt ◽  
Agata Chmurzynska

AbstractHuman gut microbiota may affect metabolism and health by synthesizing metabolites and processing of food components. Those processes are specific to genus and species (or even strain), and dietary intake and metabolic state (such as obesity) can affect the composition of gut microbiota. The aim of the study was to assess the effect of dietary patterns and intake of several groups of food products and macronutrients, as well as the impact of anthropometric parameters on gut microbiota composition.The study group consisted of 200 men and women between 31 and 50 years of age. The diet was assessed using three-day dietary records and the dietary pattern was determined with the use of the original score method and two dietary indices, namely the Diet Quality Index – International (DQI-I) and the Healthy Eating Index (HEI). Bacterial DNA was isolated from the feces of the participants and microbiota composition was determined using metagenomic sequencing of the V3–V4 region of the 16S rRNA gene.Dietary indices and intake of energy from macronutrients did not correlate with the Firmicutes to Bacteroidetes phylum ratio. However people with greater abundance of the Firmicutes phylum compared to Bacteroidetes consumed higher amounts of fermented milk beverages, hard cheese, and salt (78%, 48%, 14% higher intake respectively; p < 0.05). A higher diet quality as measured by the diet indices was positively correlated with the relative abundance of the Firmicutes phylum, Bacilli, Clostridia class, Lachnospira, Faecalibacterium, Coprococcus, and Prevotella genus and negatively correlated with the relative abundance of the Bacteroidetes phylum, Bacteroidia class, and Bacteroides genus. Higher dietary fiber intake positively correlated with the relative abundance of the Coprococcus, Lachnospira, and Roseburia genera, whereas energy intake from simple carbohydrates was positively correlated with the relative abundance of the Tenericutes phylum and the Mollicutes class. Energy intake from alcohol correlated positively with the relative abundance of Bacteroidetes phylum and Bacteroides class and correlated negatively with Firmicutes phylum and Clostridia class. Lower waist-to-hip-ratio, body mass index, and fat mass led to higher abundance of the Fecalibacterium genus.Both diet and anthropometric parameters are associated with gut microbiota composition. Associations between diet and the relative abundance of microbiota are nutrient-specific.

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