scholarly journals Multivariate Analysis in Microbiome Description: Correlation of Human Gut Protein Degraders, Metabolites, and Predicted Metabolic Functions

2021 ◽  
Vol 12 ◽  
Author(s):  
Stefano Raimondi ◽  
Rosalba Calvini ◽  
Francesco Candeliere ◽  
Alan Leonardi ◽  
Alessandro Ulrici ◽  
...  
Keyword(s):  
Intestinal Bacteria ◽  
Fecal Microbiota ◽  
Sensu Stricto ◽  
Gene Profiling ◽  
Rrna Gene ◽  
Linear Discriminant ◽  
Metabolic Functions ◽  
Genes Encoding ◽  
The Face ◽  
Microbiome Data

Protein catabolism by intestinal bacteria is infamous for releasing many harmful compounds, negatively affecting the health status, both locally and systemically. In a previous study, we enriched in protein degraders the fecal microbiota of five subjects, utilizing a medium containing protein and peptides as sole fermentable substrates and we monitored their evolution by 16S rRNA gene profiling. In the present study, we fused the microbiome data and the data obtained by the analysis of the volatile organic compounds (VOCs) in the headspace of the cultures. Then, we utilized ANOVA simultaneous component analysis (ASCA) to establish a relationship between metabolites and bacteria. In particular, ASCA allowed to separately assess the effect of subject, time, inoculum concentration, and their binary interactions on both microbiome and volatilome data. All the ASCA submodels pointed out a consistent association between indole and Escherichia–Shigella, and the relationship of butyric, 3-methyl butanoic, and benzenepropanoic acids with some bacterial taxa that were major determinants of cultures at 6 h, such as Lachnoclostridiaceae (Lachnoclostridium), Clostridiaceae (Clostridium sensu stricto), and Sutterellaceae (Sutterella and Parasutterella). The metagenome reconstruction with PICRUSt2 and its functional annotation indicated that enrichment in a protein-based medium affected the richness and diversity of functional profiles, in the face of a decrease of richness and evenness of the microbial community. Linear discriminant analysis (LDA) effect size indicated a positive differential abundance (p < 0.05) for the modules of amino acid catabolism that may be at the basis of the changes of VOC profile. In particular, predicted genes encoding functions belonging to the superpathways of ornithine, arginine, and putrescine transformation to GABA and eventually to succinyl-CoA, of methionine degradation, and various routes of breakdown of aromatic compounds yielding succinyl-CoA or acetyl-CoA became significantly more abundant in the metagenome of the bacterial community.

Direct cloning of genes encoding novel xylanases from the human gut

2005 ◽  
Vol 51 (3) ◽  
pp. 251-259 ◽  
Author(s):  
Hidenori Hayashi ◽  
Takashi Abe ◽  
Mitsuo Sakamoto ◽  
Hiroki Ohara ◽  
Toshimichi Ikemura ◽  
...  
Keyword(s):  
Intestinal Bacteria ◽  
Fecal Microbiota ◽  
Coli Strain ◽  
Amino Acid Sequences ◽  
Self Organizing Map ◽  
Human Gut ◽  
Gene Encoding ◽  
Genes Encoding ◽  
Ph Range ◽  
Self Organizing

The aim of this study was to identify a novel 1,4-β-xylanase gene from the mixed genome DNA of human fecal bacteria without bacterial cultivation. Total DNA was isolated from a population of bacteria extracted from fecal microbiota. Using PCR, the gene fragments encoding 5 different family 10 xylanases (xyn10A, xyn10B, xyn10C, xyn10D, and xyn10E) were found. Amino acid sequences deduced from these genes were highly homologous with those of xylanases from anaerobic intestinal bacteria such as Bacteroides spp. and Prevotella spp. Self-organizing map (SOM) analysis revealed that xynA10 was classified into Bacteroidetes. To confirm that one of these genes encodes an active enzyme, a full-length xyn10A gene was obtained using nested primers specific to the internal fragments and random primers. The xyn10A gene encoding the xylanase Xyn10A consists of 1146 bp and encodes a protein of 382 amino acids and a molecular weight of 43 552. Xyn10A was a single module novel xylanase. Xyn10A was purified from a recombinant Escherichia coli strain and characterized. This enzyme was optimally active at 40 °C and stable up to 50 °C at pH 6.5 and over the pH range 4.0–11.0 at 25 °C. In addition, 2 ORFs (ORF1 and ORF2) were identified upstream of xyn10A. These results suggested that many unidentified xylanolytic bacteria exist in the human gut and may contribute to the breakdown of xylan which contains dietary fiber.Key words: xylanase, human gut, fecal microbiota, phylogenetic analysis, self-organizing map.

scholarly journals Lyophilized Fecal Microbiota Transplantation Capsules for Recurrent Clostridium difficile Infection

2017 ◽  
Vol 4 (suppl_1) ◽  
pp. S381-S381
Author(s):  
Hebert Dupont ◽  
Zhi-Dong Jiang ◽  
Ashley Alexander ◽  
Nadim Ajami ◽  
Joseph F Petrosino ◽  
...  
Keyword(s):  
Oral Delivery ◽  
Fecal Microbiota Transplantation ◽  
Fecal Microbiota ◽  
Gene Profiling ◽  
Intestinal Microbiome ◽  
Published Data ◽  
Rrna Gene ◽  
Second Phase ◽  
Microbiome Diversity

Abstract Background Fecal microbiota (FM) transplantation (FMT) is a highly effective treatment of recurrent C. difficile infection (rCDI). We have published data showing efficacy of fresh, frozen and lyophilized donor microbiota administered by colonoscopy. Most groups are moving toward use of frozen product given by enema and in evaluating encapsulated product for oral delivery. Methods This was a prospective, randomized study of subjects with rCDI (≥ 3 episodes) treated with encapsulated lyophilized FM 100 g given once or 100 g given on two successive days (total 200 g) vs. frozen FM product 100 g given by single retention enema, between March 2015 and February 2017. The clinical outcome was absence of CDI during the 60 days after FMT. The subjects were followed for 6 months for safety. In a subset recipients, microbiome composition by 16S rRNA gene profiling were analyzed on stools obtained pre- and day 2, 7, 14, 30, 60 and 90 days after FMT. Results A total of 54 subjects were enrolled (37/54; 69% female) with a median age of 71 years (range: 20–97). In the first 14 subjects treated, cure rates for oral capsules 100 g FM was 5/8 (63%) vs. 6/6 (100%) for those receiving 100 g frozen FM by enema (P = 0.209). In the second phase of the study cure rate for oral capsules 200 g FM was 17/18 (91%) vs. 20/21 (94%) for the subjects treated by enema by 100 g of frozen product (P = 0.782). No side effects were felt to be related to the procedure or the FMT products were recorded during 6 months follow-up. Two subjects died during follow-up between 3 and 6 months after study due to underlying medical conditions felt to be unrelated to FMT. Microbiota analysis were performed on 40 subjects of which 19/40 (48%) had received capsules. Figure showed that restoration of the intestinal microbiome diversity and Taxa began apparent by 2 days after FMT in both groups and resembled the donor product by 2 weeks with stabilization of the microbiota diversity and Taxa persisting for the 90 days of observation. Conclusion Administration of encapsulated, lyophilized FM resulted in durable restoration of intestinal microbiome diversity comparable to results seen with frozen product given by enema. Disclosures All authors: No reported disclosures.

scholarly journals Change in Bacterial Diversity of Fecal Microbiota Drives Mortality in a Hamster Model of Antibiotic-induced Clostridium difficile Colitis

2017 ◽  
Vol 4 (suppl_1) ◽  
pp. S382-S382
Author(s):  
Charles Burdet ◽  
Thu Thuy Nguyen ◽  
Nathalie Saint-Lu ◽  
Sakina Sayah-Jeanne ◽  
Perrine Hugon ◽  
...  
Keyword(s):  
Bacterial Diversity ◽  
Diversity Indices ◽  
Fecal Microbiota ◽  
Gene Profiling ◽  
Rrna Gene ◽  
Hamster Model ◽  
Unweighted Unifrac ◽  
Curtis Dissimilarity ◽  
Oral Adsorbent ◽  
Induced Changes

Abstract Background C. difficile (C diff) infection results from antibiotic-induced changes in colonic microbiota. DAV131A, an oral adsorbent-based product, can sequester antibiotic (AB) residues in the gut and reduce mortality in a hamster model of moxifloxacin (MXF) or clindamycin (CM) induced C diffcolitis. We studied the link between changes of the bacterial diversity within the fecal microbiota and mortality in this model. Methods Male Syrian hamsters were administered 30 mg/kg MXF or 5 mg/kg CM subcutaneously once a day for 5 days (D1 to D5) and orally infected at D3 with 104C diffspores. They were orally administered various doses of DAV131A (0, and 200 to 900 mg/kg twice a day), from D1 to D8. Survival was monitored up to D16 and feces were collected (D1 and D3) to characterize the microbiota by 16S rRNA gene profiling. Changes of various α- (Shannon, Observed OTUs and Chao1) and β- (Bray-Curtis dissimilarity and [un]weighted UniFrac) diversity indices between D1 and D3 were obtained for each animal. We analyzed links between (i) DAV131A dose and changes of bacterial diversity and (ii) changes of bacterial diversity and mortality using non parametric tests and logistic regression. Results Data from 70 and 60 animals were available in the MXF and CM studies, among which 10 and 28 died, respectively. Increasing doses of DAV131A reduced mortality from 100% to 0% and reduced changes in bacterial diversity of the fecal microbiota. Very strong predictors of mortality were changes in Shannon and unweighted UniFrac indices, which were markedly less affected in hamsters who survived (see table below median (min; max) according to vital status and area under the ROC curve, AUROC). Conclusion The extent of AB-induced changes in gut bacterial diversity correlated with increased mortality in a hamster model of C diff colitis. Higher doses of DAV131A protected fecal microbiota disruption and hence mortality. Disclosures C. Burdet, Da Volterra: Consultant and Research Contractor, Consulting fee; N. Saint-Lu, Da Volterra: Employee, Salary; S. Sayah-Jeanne, Da Volterra: Employee, Salary; P. Hugon, Da Volterra: Employee, Salary; F. Sablier-Gallis, Da Volterra: Employee, Salary; S. Ferreira, Genoscreen: Employee, Salary; A. Andremont, Da Volterra: Consultant, Consulting fee; F. Mentré, Da Volterra: Consultant and Research Contractor, Consulting fee; J. De Gunzburg, Da Volterra: Consultant and Shareholder, Consulting fee

scholarly journals Comprehensive Survey of the Litter Bacterial Communities in Commercial Turkey Farms

2020 ◽  
Vol 7 ◽  
Author(s):  
Bishnu Adhikari ◽  
Guillermo Tellez-Isaias ◽  
Tieshan Jiang ◽  
Brian Wooming ◽  
Young Min Kwon
Keyword(s):  
Bacterial Communities ◽  
Animal Species ◽  
Sensu Stricto ◽  
Gene Profiling ◽  
Farm Animals ◽  
Rrna Gene ◽  
Microbial Composition ◽  
Bacterial Phyla ◽  
Comprehensive Survey ◽  
Commercial Turkey

The importance of microbiota in the health and diseases of farm animals has been well-documented for diverse animal species. However, studies on microbiotas in turkey and turkey farms are relatively limited as compared to other farm animal species. In this study, we performed a comprehensive survey of the litter microbiotas in 5 commercial turkey farms in the Northwest Arkansas (H, M, V, K, and R farms) including one farm with positive incidence of cellulitis (R farm). Altogether 246 boot swabs were used for 16S rRNA gene profiling of bacterial communities. At phylum level, 11 major bacterial phyla (≥0.01%) were recovered. At genus level, 13 major bacterial genera were found whose relative abundance were ≥2%. The microbial composition at both phylum and genus levels as well as their diversities varied across different farms, which were further affected by different flocks within the same farms and the ages of turkeys. Generally, the Firmicutes were higher in the flocks of younger birds, while the Actinobacteria and Bacteroidetes were higher in the flocks of the older birds. The Proteobacteria were highly enriched (47.97%) in K farm housing 56-day-old turkeys (K-56), but Bacteroidetes were found the highest in the flock C of M farm housing 63-day-old turkeys (M-C-63; 22.38%), followed by K-84 group (17.26%). Four core bacterial genera (Staphylococcus, Brevibacterium, Brachybacterium, and Lactobacillus) were identified in all samples except for those from R farm. In contrast, 24 core bacterial genera were found based in all cellulitis-associated samples (R farm), including Corynebacterium, an unknown genus of family Bacillaceae, Clostridium sensu stricto 1 (>97% similarity with C. septicum), and Ignatzschineria among others, suggesting their possible roles in etiopathogenesis of cellulitis in turkeys. Overall results of this study may provide valuable foundation for future studies focusing on the role of microbiota in the health and diseases of turkeys.

scholarly journals Higher fiber complementary food alters Fecal microbiota composition and normalizes stool form in Malawian children: A randomized trial

2021 ◽  
Vol 21 (04) ◽  
pp. 17854-17875
Author(s):  
Edda Lungu ◽  
◽  
J Auger ◽  
A Piano ◽  
WJ Dahl ◽  
...  
Keyword(s):  
Dietary Intake ◽  
Bacterial Species ◽  
Amplicon Sequencing ◽  
Fecal Microbiota ◽  
Stool Frequency ◽  
Sub Saharan Africa ◽  
Rrna Gene ◽  
Microbiota Composition ◽  
Linear Discriminant ◽  
Stool Form

Dietary fiber favorably modulates gut microbiota and may be protective against diarrhea in sub-Saharan Africa where rates in infants and young children are high. Soybean hull is high in fiber and accessible in rural Africa; however, its use in complementary feeding has not been evaluated. The objective of this study was to determine the acceptability and feasibility of a soybean, soy hull fiber, and maize (SFM) blend food; the primary outcome was compliance to the feeding protocol. Secondary outcomes were stool form and frequency, fecal microbiota composition, growth and dietary intake. In a parallel, single-blind study, children 6-36 months of age from the Lilongwe district of Malawi were randomized to receive daily SFM (n=69) or maize only(n=10) porridge(phala) for 6 months. Anthropometrics were measured monthly, and compliance, stool frequency,and stool form, weekly. At baseline, 3-month,and 6-month (study end) time points, dietary intake (24-h recall) was assessed,and fecal samples were collected. Fecal DNA was analyzed by Real-Time polymerase chain reaction (PCR) for microbes of interest and 16S rRNA gene amplicon sequencing. Mothers accessed the acceptability and feasibility of the study foods at study end. Mothers reported excellent compliance to feeding the SFM porridge, rated it more acceptable than maize,and noted improved appetite, weight, and stool consistency of their children. Stool frequency at baseline (2±1 stools/d) was unchanged with intervention; however, there were significantly fewer diarrhea-type stools reported during study months 4-6 vs.1-3 for the SFM group, whereas no improvement was seen for the maize group. At study end, the fecal abundance ofAkkermansia muciniphila was enriched in children receiving the SFM, compared to maize (p<0.05), and a trend for increased Faecalibacterium prausnitzii (p=0.07) was seen. A comparison of fecal microbiota composition using linear discriminant analysis effect size (LEfSe)showed notable differences in numerous taxa in the SFM group compared to baseline, whereas the maize comparator exhibited fewer changes. Fiber intake was higher for the SFMgroup, compared to maize at 6 months (13.7±3.8 vs. 8.4±4.5 g/day, p<0.01). Weight-for-height and BMI-for-age Z-scores were significantly higher for the SFM group. In young Malawian children, feeding a blend of soybean, soy hulls and maize reduced diarrhea-type stools and increased the abundance of Akkermansia muciniphila, a bacterial species involved in maintaining intestinal health, and thus may provide a feasible means of improving wellness in children in resource-poor settings through the modulation of microbiota composition.

scholarly journals P683 Patients with newly diagnosed fistulizing perianal Crohn’s disease have a distinct microbial signature

2021 ◽  
Vol 15 (Supplement_1) ◽  
pp. S602-S602
Author(s):  
I Goren ◽  
W Ian ◽  
L Reshef ◽  
T Sharar Fischler ◽  
M Pauker ◽  
...  
Keyword(s):  
Crohn’S Disease ◽  
Crohn's Disease ◽  
16S Rrna Gene Sequencing ◽  
Fecal Calprotectin ◽  
Fecal Microbiota ◽  
Rrna Gene ◽  
Newly Diagnosed ◽  
Linear Discriminant ◽  
Microbial Dysbiosis ◽  
Log Ratio

Abstract Background Alterations in gut bacterial microbiota are strongly associated with the pathogenesis of Crohn’s disease (CD). Up to 1/3 of patients with CD have perianal involvement (P-CD), either fistulizing (f-P-CD) or non-fistulizing (nf-P-CD). We hypothesized that alterations in fecal microbiota might drive perianal CD phenotypes. Methods Patients with newly diagnosed treatment naive CD were consecutively recruited. Patients were stratified into f-P-CD and nf-P-CD, and compared with CD without perianal involvement (non-P-CD). Bacterial 16S rRNA gene sequencing was performed. Microbial dysbiosis index (MDI), Shannon diversity score (H) and log ratio between anaerobic and aerobic bacteria (anaerobic index, AI) were calculated. Linear discriminant analysis effect size (LEfSe) was used to identify specific taxa discriminating between different patient groups. Fecal calprotectin (FC) was measured. Results We included 97 CD patients (50 males, median age 28 [IQR 22–41] years). Other than perianal involvement patients in both groups had comparable distribution of CD location and phenotype. The microbial indices MDI, H and AI as well as FC levels, did not differ between the P-CD (n=25) and non-P-CD (n=72) groups. When compared to non-P-CD, the P-CD exhibited significantly lower relative abundance in the Streptococci genera (p=0.01) and in the Ruminiclostridium_5 genera (p=0.02). Within the P-CD group, patients with f-P-CD (n=12) had significantly lower H than those with nf-P-CD (means: 2.0 vs 2.45, p=0.045), while FC levels were comparable between f-P-CD and nf-P-CD. Moreover, proportions of Coprococcus_3 and Lacnoclostridium were reduced in patients with f-P-CD vs nf-P-CD (p= 0.008, p=0.05, respectively), while Streptococcus was elevated (p=0.03). Conclusion Perianal CD is a spectrum with distinct microbial alterations in different phenotypes. Microbial alterations correspond to the severity of perianal involvement. This finding may suggest that the microbiome has a mechanistic role in complicated perianal CD.

Dysbiosis of Fecal Microbiota in Allergic Rhinitis Patients

2020 ◽  
Vol 34 (5) ◽  
pp. 650-660 ◽  
Author(s):  
Xiang Liu ◽  
Jing Tao ◽  
Jing Li ◽  
Xiaolin Cao ◽  
Yong Li ◽  
...  
Keyword(s):  
Allergic Rhinitis ◽  
Statistical Analysis ◽  
Gut Microbiota ◽  
Study Groups ◽  
Fecal Microbiota ◽  
Rrna Gene ◽  
Microbiota Composition ◽  
Linear Discriminant ◽  
Α Diversity ◽  
Gut Microbiota Composition

Background The gut microbiota plays an important role in shaping the immune system and may be closely connected to the development of allergic diseases. Objective This study aimed to determine the gut microbiota composition in Chinese allergic rhinitis (AR) patients as compared with healthy controls (HCs). Methods We collected stool samples from 93 AR patients and 72 age- and sex-matched HCs. Gut microbiota composition was analyzed using QIIME targeting the 16S rRNA gene. Functional pathways were predicted using Phylogenetic Investigation of Communities by Reconstruction of Unobserved States. Statistical analysis was performed using the R program, linear discriminant analysis effect size (LefSe), analysis of QIIME, and statistical analysis of metagenomic profiles, among other tests. Results Compared with HCs, AR patients had significantly lower gut-microbiota α-diversity ( P < .001). The gut microbiota composition significantly differed between the 2 study groups. At the phylum level, the relative abundance of Bacteroidetes was higher while those of Actinobacteria and Proteobacteria were lower in the AR group than in the HC group ( P < .001, q < 0.001). At the genus level, Escherichia-Shigella, Prevotella, and Parabacteroides ( P < .001, q < 0.001) had significantly higher relative abundances in the AR group than in the HC group. LefSe analysis indicated that Escherichia-Shigella, Lachnoclostridium, Parabacteroides, and Dialister were potential biomarkers for AR. In addition, predictive metagenome functional analysis showed that pyruvate, porphyrin, chlorophyll, purine metabolism, and peptidoglycan biosynthesis significantly differed between the AR and HC groups. Conclusion A comparison of the gut microbiota of AR patients and HCs suggested that dysbiosis of the fecal microbiota is involved in the development of AR. The present results may reveal key differences and identify targets for preventive or therapeutic intervention.

scholarly journals Altered Fecal Microbiota Composition Associated with Food Allergy in Infants

2014 ◽  
Vol 80 (8) ◽  
pp. 2546-2554 ◽  
Author(s):  
Zongxin Ling ◽  
Zailing Li ◽  
Xia Liu ◽  
Yiwen Cheng ◽  
Yueqiu Luo ◽  
...  
Keyword(s):  
Food Allergy ◽  
Intestinal Microbiota ◽  
Fecal Microbiota ◽  
Sensu Stricto ◽  
Rrna Gene ◽  
Microbiota Composition ◽  
Human Beings ◽  
Actual Structure ◽  
Content Type ◽  
Ige Mediated

ABSTRACTIncreasing evidence suggests that perturbations in the intestinal microbiota composition of infants are implicated in the pathogenesis of food allergy (FA), while the actual structure and composition of the intestinal microbiota in human beings with FA remain unclear. Microbial diversity and composition were analyzed with parallel barcoded 454 pyrosequencing targeting the 16S rRNA gene hypervariable V1-V3 regions in the feces of 34 infants with FA (17 IgE mediated and 17 non-IgE mediated) and 45 healthy controls. Here, we showed that several key FA-associated bacterial phylotypes, but not the overall microbiota diversity, significantly changed in infancy fecal microbiota with FA and were associated with the development of FA. The proportion of abundantBacteroidetes,Proteobacteria, andActinobacteriaphyla were significantly reduced, while theFirmicutesphylum was highly enriched in the FA group (P< 0.05). AbundantClostridiaceae1 organisms were prevalent in infants with FA at the family level (P= 0.016). FA-enriched phylotypes negatively correlated with interleukin-10, for example, the generaEnterococcusandStaphylococcus. Despite profound interindividual variability, levels of 20 predominant genera were significantly different between the FA and healthy control groups (P< 0.05). Infants with IgE-mediated FA had increased levels ofClostridium sensu strictoandAnaerobacterand decreased levels ofBacteroidesandClostridiumXVIII (P< 0.05). A positive correlation was observed betweenClostridium sensu strictoand serum-specific IgE (R= 0.655,P< 0.001). The specific microbiota signature could distinguish infants with IgE-mediated FA from non-IgE-mediated ones. Detailed microbiota analysis of a well-characterized cohort of infants with FA showed that dysbiosis of fecal microbiota with several FA-associated key phylotypes may play a pathogenic role in FA.

scholarly journals Gut Microbiota and Liver Fibrosis: One Potential Biomarker for Predicting Liver Fibrosis

2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Zhiming Li ◽  
Ming Ni ◽  
Haiyang Yu ◽  
Lili Wang ◽  
Xiaoming Zhou ◽  
...  
Keyword(s):  
Random Forest ◽  
Liver Fibrosis ◽  
Gut Microbiota ◽  
Control Group ◽  
Rrna Gene ◽  
Linear Discriminant ◽  
Random Forest Classification ◽  
Metabolic Functions ◽  
Forest Classification ◽  
Potential Biomarker

Purpose. To investigate the relationship between gut microbiota and liver fibrosis and establish a microbiota biomarker for detecting and staging liver fibrosis. Methods. 131 Wistar rats were used in our study, and liver fibrosis was induced by carbon tetrachloride. Stool samples were collected within 72 hours after the last administration. The V4 regions of 16S rRNA gene were amplified. The sequencing data was processed using the Quantitative Insights Into Microbial Ecology (QIIME version 1.9). The diversity, principal coordinate analysis (PCoA), nonmetric multidimensional scaling (NMDS), and linear discriminant analysis (LDA) effect size (LEfSe) were performed. Random-Forest classification was performed for discriminating the samples from different groups. Microbial function was assessed using the PICRUST. Results. The Simpson in the control group was lower than that in the liver fibrosis group (p=0.048) and differed significantly among different fibrosis stages (p=0.047). The Chao1 index in the control group was higher than that in the liver fibrosis group (p<0.001). NMDS analysis showed a marked difference between the control and liver fibrosis groups (p<0.001). PCoA analysis indicated the different community composition between the control and liver fibrosis groups with variances of PC1 13.76% and PC2 5.89% and between different liver fibrosis stages with variances of PC1 10.51% and PC2 7.78%. LEfSe analysis showed alteration of gut microbiota in the liver fibrosis group. Biomarkers obtained from Random-Forest classification showed excellent diagnostic accuracy in prediction of liver fibrosis with AUROCs of 0.99. The AUROCs were 0.77~0.84 in prediction of stage F4. There were six increased and 17 decreased metabolic functions in the liver fibrosis group and 6 metabolic functions significantly differed among four liver fibrosis stages. Conclusion. Gut microbiota is a potential biomarker for detecting and staging liver fibrosis with high diagnostic accuracies.

scholarly journals Gastric microbial community profiling reveals a dysbiotic cancer-associated microbiota

Gut ◽  
2017 ◽  
Vol 67 (2) ◽  
pp. 226-236 ◽  
Author(s):  
Rui M Ferreira ◽  
Joana Pereira-Marques ◽  
Ines Pinto-Ribeiro ◽  
Jose L Costa ◽  
Fatima Carneiro ◽  
...  
Keyword(s):  
Microbial Community ◽  
Gastric Carcinoma ◽  
Chronic Gastritis ◽  
Gene Profiling ◽  
Rrna Gene ◽  
Microbial Composition ◽  
Linear Discriminant ◽  
Microbial Dysbiosis ◽  
Functional Features ◽  
Gastric Microbiota

ObjectiveGastric carcinoma development is triggered by Helicobacter pylori. Chronic H. pylori infection leads to reduced acid secretion, which may allow the growth of a different gastric bacterial community. This change in the microbiome may increase aggression to the gastric mucosa and contribute to malignancy. Our aim was to evaluate the composition of the gastric microbiota in chronic gastritis and in gastric carcinoma.DesignThe gastric microbiota was retrospectively investigated in 54 patients with gastric carcinoma and 81 patients with chronic gastritis by 16S rRNA gene profiling, using next-generation sequencing. Differences in microbial composition of the two patient groups were assessed using linear discriminant analysis effect size. Associations between the most relevant taxa and clinical diagnosis were validated by real-time quantitative PCR. Predictive functional profiling of microbial communities was obtained with PICRUSt.ResultsThe gastric carcinoma microbiota was characterised by reduced microbial diversity, by decreased abundance of Helicobacter and by the enrichment of other bacterial genera, mostly represented by intestinal commensals. The combination of these taxa into a microbial dysbiosis index revealed that dysbiosis has excellent capacity to discriminate between gastritis and gastric carcinoma. Analysis of the functional features of the microbiota was compatible with the presence of a nitrosating microbial community in carcinoma. The major observations were confirmed in validation cohorts from different geographic origins.ConclusionsDetailed analysis of the gastric microbiota revealed for the first time that patients with gastric carcinoma exhibit a dysbiotic microbial community with genotoxic potential, which is distinct from that of patients with chronic gastritis.

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