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Microbiology (Reading, England) Jul 1999The ruminococci are an important group of fibrolytic bacteria inhabiting the rumen. Seventeen strains of presumptively identified Ruminococcus were evaluated by a...
The ruminococci are an important group of fibrolytic bacteria inhabiting the rumen. Seventeen strains of presumptively identified Ruminococcus were evaluated by a combination of nearly complete and partial 16S rDNA sequence that identified all strains as either Ruminococcus albus or Ruminococcus flavefaciens. All sequences fell into cluster IV of the clostridia, while other species of ruminococci (e.g. Ruminococcus obeum, Ruminococcus gnavus, Ruminococcus lactaris) fall into cluster XIVa of the clostridia. Ruminococcus cluster IV sequences were used to design a 16S rRNA oligonucleotide probe to assess the relative abundance of target populations in a stable ruminal environment. A stable population (animals fed eight times per day) was established in sheep so that statistically robust comparisons could be made in the absence of variation due to diurnal rumen fluctuations. The steady state populations were sampled six times over a 24 d period and direct microscopic counts (DC), total culturable counts (TCC), and total cellulolytic counts (CEL) were determined. DC and culturable data (TCC and CEL) were compared with relative abundance estimates of Ruminococcus IV and Fibrobacter succinogenes. A combination of the Ruminococcus and F. succinogenes probes accounted for 4.0% of the bacterial population and cellulolytic bacteria (measured by most-probable numbers) were 5.2% of the total culturable count. These data suggest that a major portion of the Ruminococcus and Fibrobacter diversity has been cultured and is represented by available sequences. Steady state populations were measured over several days in three sheep and an estimate of variation in DC, TCC, CEL and 16S-based data were obtained. These variance estimates could be used to determine the theoretical sample sizes required to obtain statistically significant differences under different experimental conditions.
Topics: Animals; Colony Count, Microbial; DNA, Bacterial; DNA, Ribosomal; Gram-Positive Cocci; Molecular Sequence Data; Nucleic Acid Hybridization; Oligonucleotide Probes; Phylogeny; Polymorphism, Restriction Fragment Length; RNA, Ribosomal, 16S; Rumen; Sequence Analysis, DNA; Sheep
PubMed: 10439419
DOI: 10.1099/13500872-145-7-1797 -
Frontiers in Neurology 2020Gut bacteria play an important role in the pathogenesis of Parkinson's disease (PD). However, the alteration of fecal microbiota in PD with cognitive impairment remains...
Gut bacteria play an important role in the pathogenesis of Parkinson's disease (PD). However, the alteration of fecal microbiota in PD with cognitive impairment remains unexplored. This study aimed to explore whether the gut microbiota of patients with PD having mild cognitive impairment (PD-MCI) were different from those with PD having normal cognition (PD-NC) and from healthy controls (HC). Also, the study probed the association between altered gut microbiota and cognitive ability in patients with PD. The fecal bacteria composition and short-chain fatty acids of 13 patients with PD-MCI, 14 patients with PD-NC, and 13 healthy spouses were analyzed using 16S ribosomal RNA sequencing and gas chromatography-mass spectrometry. Compared with HC, the fecal microbial diversities increased in patients with PD-MCI and PD-NC. After adjusting the influence of age, sex, body mass index, education, and constipation using the statistical method, the relative abundances of two families (Rikenellaceae and Ruminococcaceae) and four genera (, and ) were found to be higher in the feces of the PD-MCI group compared with the other two groups. Moreover, the abundance of genus and decreased obviously in the PD-MCI group compared with the PD-NC group. Further, the abundance of genera , and negatively correlated with cognition ability. Compared with HC and patients with PD-NC, the gut microbiota of patients with PD-MCI was significantly altered, particularly manifesting in enriched genera from Porphyromonadaceae family and decreased the abundance of genera and .
PubMed: 32161568
DOI: 10.3389/fneur.2020.00137 -
World Journal of Gastroenterology Oct 2018To investigate the effects of VSL#3 on tumor formation, and fecal and intestinal mucosal microbiota in azoxymethane/dextran sulfate sodium (AOM/DSS) induced mice model.
AIM
To investigate the effects of VSL#3 on tumor formation, and fecal and intestinal mucosal microbiota in azoxymethane/dextran sulfate sodium (AOM/DSS) induced mice model.
METHODS
C57BL/6 mice were administered AOM/DSS to develop the ulcerative colitis (UC) carcinogenesis model. Mice were treated with 5-ASA (75 mg/kg/d), VSL#3 (1.5 × 10 CFU/d), or 5-ASA combined with VSL#3 by gavage from the day of AOM injection for three months (five days/week). The tumor load was compared in each group, and tumor necrosis factor (TNF-α) and interleukin (IL)-6 levels were evaluated in colon tissue. The stool and intestinal mucosa samples were collected to analyze the differences in the intestinal microbiota by 16s rDNA sequencing method.
RESULTS
VSL#3 significantly reduced the tumor load in AOM/DSS-induced mice model and decreased the level of TNF-α and IL-6 in colon tissue. The model group had a lower level of and higher level of and in fecal microbiota than the control group. After the intervention with 5-ASA and VSL#3, and were increased, while and were reduced. 5-ASA combined with VSL#3 increased the and decreased the . The intestinal mucosal microbiota analysis showed a lower level of and _UCG-014 and higher level of in the model group as compared to the control group. After supplementation with VSL#3, was increased. 5-ASA combined with VSL#3 increased the level of both and .
CONCLUSION
VSL#3 can prevent UC-associated carcinogenesis in mice, reduce the colonic mucosal inflammation levels, and rebalance the fecal and mucosal intestinal microbiota.
Topics: Animals; Bifidobacterium; Carcinogenesis; Colitis, Ulcerative; Colon; DNA Damage; Disease Models, Animal; Gastrointestinal Microbiome; Interleukin-6; Intestinal Neoplasms; Lactobacillus; Male; Mice; Mice, Inbred C57BL; Probiotics; RNA, Ribosomal, 16S; Ruminococcus; Sequence Analysis, DNA; Tumor Necrosis Factor-alpha
PubMed: 30310258
DOI: 10.3748/wjg.v24.i37.4254 -
Frontiers in Microbiology 2023Milk fat is the most variable nutrient in milk, and recent studies have shown that rumen bacteria are closely related to milk fat. However, there is limited research on...
INTRODUCTION
Milk fat is the most variable nutrient in milk, and recent studies have shown that rumen bacteria are closely related to milk fat. However, there is limited research on the relationship between rumen bacteria and milk fatty. Fatty acids (FAs) are an important component of milk fat and are associated with various potential benefits and risks to human health.
METHODS
In this experiment, forty-five healthy Holstein dairy cows with alike physiological and productive conditions were selected from medium-sized dairy farms and raised under the same feeding and management conditions. The experimental period was two weeks. During the experiment, raw milk and rumen fluid were collected, and milk components were determined. In this study, 8 high milk fat percentage (HF) dairy cows and 8 low milk fat percentage (LF) dairy cows were selected for analysis.
RESULTS
Results showed that the milk fat percentage in HF group was significantly greater than that of the dairy cows in the LF group. 16S rRNA gene sequencing showed that the rumen bacterial abundance of HF dairy cows was significantly higher than that in LF dairy cows; at the genus level, the bacterial abundances of , _1, , , and in HF group were significantly higher than those in the LF group. Spearman rank correlation analysis indicated that milk fat percentage was positively related to _1, , , and . Furthermore, was positively related to C14:0 iso, C15:0 iso, C18:0, _1 with C18:1 t9, with C18:1 t9 and C18:1 t11, with C15:0 iso.
DISCUSSION
To sum up, rumen bacteria in dairy cows are related to the variation of milk fat, and some rumen bacteria have potential effects on the deposition of certain fatty acids in raw milk.
PubMed: 37886063
DOI: 10.3389/fmicb.2023.1247348 -
Animal : An International Journal of... Sep 2014Information available on the role of Mg for growth and cellulose degradation by rumen bacteria is both limited and inconsistent. In this study, the Mg requirements for...
Information available on the role of Mg for growth and cellulose degradation by rumen bacteria is both limited and inconsistent. In this study, the Mg requirements for two strains each of the cellulolytic rumen species Fibrobacter succinogenes (A3c and S85), Ruminococcus albus (7 and 8) and Ruminococcus flavefaciens (B34b and C94) were investigated. Maximum growth, rate of growth and lag time were all measured using a complete factorial design, 2(3)×6; factors were: strains (2), within species (3) and Mg concentrations (6). R. flavefaciens was the only species that did not grow when Mg was singly deleted from the media, and both strains exhibited a linear growth response to increasing Mg concentrations (P<0.001). The requirement for R. flavefaciens B34b was estimated as 0.54 mM; whereas the requirement for R. flavefaciens C94 was >0.82 as there was no plateau in growth. Although not an absolute requirement for growth, strains of the two other species of cellulolytic bacteria all responded to increasing Mg concentrations. For F. succinogenes S85, R. albus 7 and R. albus 8, their requirement estimated from maximum growth was 0.56, 0.52 and 0.51, respectively. A requirement for F. succinogenes A3c could not be calculated because there was no solution for contrasts. Whether R. flavefaciens had a Mg requirement for cellulose degradation was determined in NH3-free cellulose media, using a 2×4 factorial design, 2 strains and 4 treatments. Both strains of R. flavefaciens were found to have an absolute Mg requirement for cellulose degradation. Based on reported concentrations of Mg in the rumen, 1.0 to 10.1 mM, it seems unlikely that an in vivo deficiency of this element would occur.
Topics: Animals; Calcium; Cellobiose; Cellulose; Culture Media; Fibrobacter; Logistic Models; Magnesium; Rumen; Ruminococcus
PubMed: 24846132
DOI: 10.1017/S1751731114001207 -
Clinical and Translational... Jul 2022We previously reported a lower fecal abundance of Ruminococcus spp., Faecalibacterium prausnitzii , and Coprococcus spp. in nonalcoholic fatty liver disease (NAFLD). In...
INTRODUCTION
We previously reported a lower fecal abundance of Ruminococcus spp., Faecalibacterium prausnitzii , and Coprococcus spp. in nonalcoholic fatty liver disease (NAFLD). In this article, we assess the associations between hepatic gene expression, the specific taxa, and bacterial pathways.
METHODS
The relationships between hepatic genes that were differentially expressed in patients with NAFLD vs healthy controls (HC) and the abundance of these specific taxa were studied. Inferred functional metagenomic analysis using Piphillin was also performed to investigate associations with bacterial pathways.
RESULTS
Fifteen patients with NAFLD and 6 HC participated. Of 728 hepatic genes examined, 176 correlated with the abundance of Ruminococcus spp., 138 with F. prausnitzii , and 92 with Coprococcus spp. For Ruminococcus spp., genes were enriched in gene ontology (GO) terms related to apoptotic process, response to external and cytokine stimuli, and regulation of signaling. Several genes related to the Kyoto Encyclopedia of Genes and Genomes pathway insulin resistance were correlated with F. prausnitzii . The hepatic genes associated with F. prausnitzii were enriched in GO terms related to cellular response to different stimuli, apoptotic process, and regulation of metabolic pathways. For Coprococcus spp., only the GO term response to external stimulus was enriched. There was a distinct pattern of associations between hepatic genes and bacterial taxa in NAFLD vs HC. For bacterial pathways, 65 and 18 hepatic genes correlated with bacterial metabolic functions in NAFLD and HC, respectively.
DISCUSSION
Hepatic gene expression related to insulin resistance, inflammation, external stimuli, and apoptosis correlated with bacterial taxa. Patients with NAFLD showed a higher presence of bacterial pathways associated with lipid metabolism.
Topics: Bacteria; Gastrointestinal Microbiome; Gene Expression; Humans; Insulin Resistance; Non-alcoholic Fatty Liver Disease
PubMed: 35166723
DOI: 10.14309/ctg.0000000000000466 -
Metabolites Oct 2018The aim of the present study was to assess the malodorous spoilages of Spanish-style green table olives through microbial and metabolite composition using current...
The aim of the present study was to assess the malodorous spoilages of Spanish-style green table olives through microbial and metabolite composition using current measuring techniques (e.g., high-throughput DNA sequencing, headspace solid-phase microextraction combined with gas chromatography-mass spectrometry). Under different alkaline and washing conditions, the spoilage fermentations were reproduced with Gordal and Manzanilla olive cultivars using a low salt concentration (71 g L NaCl) in the initial brine. The degradation of lactic acid and significant increases in volatile fatty acids and phenols were found in all the spoiled samples in comparison with the unspoiled control samples. According to high-throughput DNA sequencing, and were the dominant bacteria in the spoiled samples. PLS regression and Pearson's correlation coefficient analyses revealed positive and negative correlations among microbial communities, metabolites, and sensory spoilage descriptors. Notably, the "zapatera" descriptor was significantly associated with , which was positively correlated with acetic acid, propionic acid, succinic acid, and methyl propanoate; while the "butyric" descriptor exhibited a significant positive relationship with the genus , which gave an almost significant correlation with propionic and butyric acids.
PubMed: 30384453
DOI: 10.3390/metabo8040073 -
Journal of Applied Microbiology Jan 2018The objective was to determine the effect of the isoflavone biochanin A (BCA) on rumen cellulolytic bacteria and consequent fermentative activity.
AIMS
The objective was to determine the effect of the isoflavone biochanin A (BCA) on rumen cellulolytic bacteria and consequent fermentative activity.
METHODS AND RESULTS
When bovine microbial rumen cell suspensions (n = 3) were incubated (24 h, 39°C) with ground hay, cellulolytic bacteria proliferated, short-chain fatty acids were produced and pH declined. BCA (30 μg ml ) had no effect on the number of cellulolytic bacteria or pH, but increased acetate, propionate and total SCFA production. Addition of BCA improved total digestibility when cell suspensions (n = 3) were incubated (48 h, 39°C) with ground hay, Avicel, or filter paper. Fibrobacter succinogenes S85, Ruminococcus flavefaciens 8 and Ruminococcus albus 8 were directly inhibited by BCA. Synergistic antimicrobial activity was observed with BCA and heat killed cultures of cellulolytic bacteria, but the effects were species dependent.
CONCLUSIONS
These results indicate that BCA improves fibre degradation by influencing cellulolytic bacteria competition and guild composition.
SIGNIFICANCE AND IMPACT OF THE STUDY
BCA could serve as a feed additive to improve cellulosis when cattle are consuming high-fibre diets. Future research is needed to evaluate the effect of BCA on fibre degradation and utilization in vivo.
Topics: Animal Feed; Animals; Cattle; Dietary Fiber; Fatty Acids, Volatile; Fermentation; Fibrobacter; Genistein; Rumen; Ruminococcus
PubMed: 29112792
DOI: 10.1111/jam.13632 -
Diabetes, Metabolic Syndrome and... 2024( is a gram-positive anaerobe commonly resides in the human gut microbiota. The advent of metagenomics has linked with various diseases, including inflammatory bowel... (Review)
Review
( is a gram-positive anaerobe commonly resides in the human gut microbiota. The advent of metagenomics has linked with various diseases, including inflammatory bowel disease (IBD), obesity, and diabetes mellitus (DM), which has become a growing area of investigation. The initial focus of research primarily centered on assessing the abundance of and its potential association with disease presentation, taking into account variations in sample size, sequencing and analysis methods. However, recent investigations have shifted towards elucidating the underlying mechanistic pathways through which may contribute to disease manifestation. In this comprehensive review, we aim to provide an updated synthesis of the current literature on in the context of IBD, obesity, and DM. We critically analyze relevant studies and summarize the potential molecular mediators implicated in the association between and these diseases. Across numerous studies, various molecules such as methylation-controlled J (MCJ), glucopolysaccharides, ursodeoxycholic acid (UDCA), interleukin(IL)-10, IL-17, and capric acid have been proposed as potential contributors to the link between and IBD. Similarly, in the realm of obesity, molecules such as hydrogen peroxide, butyrate, and UDCA have been suggested as potential mediators, while glycine ursodeoxycholic acid (GUDCA) has been implicated in the connection between and DM. Furthermore, it is imperative to emphasize the necessity for additional studies to evaluate the potential efficacy of targeting pathways associated with as a viable strategy for managing these diseases. These findings have significantly expanded our understanding of the functional role of in the context of IBD, obesity, and DM. This review aims to offer updated insights into the role and potential mechanisms of , as well as potential strategies for the treatment of these diseases.
PubMed: 38496006
DOI: 10.2147/DMSO.S456173 -
Frontiers in Immunology 2023Tuft cells are a type of rare epithelial cells that have been recently found to utilize taste signal transduction pathways to detect and respond to various noxious...
Tuft cells are a type of rare epithelial cells that have been recently found to utilize taste signal transduction pathways to detect and respond to various noxious stimuli and pathogens, including allergens, bacteria, protists and parasitic helminths. It is, however, not fully understood how many different types of pathogens they can sense or what exact molecular mechanisms they employ to initiate targeted responses. In this study, we found that an anaerobic pathobiont microbe, (), can induce tuft cell proliferation in the proximal colon whereas the microbe's lysate can stimulate these proximal colonic tuft cells to release interleukin-25 (IL-25). Nullification of the and genes that encode the G protein subunit Gγ13 and transient receptor potential ion channel Trpm5, respectively, or application of the Tas2r inhibitor allyl isothiocyanate (AITC), G protein Gβγ subunit inhibitor Gallein or the phospholipase Cβ2 (PLCβ2) inhibitor U73122 reduces -elicited tuft cell proliferation or IL-25 release or both. Furthermore, conditional knockout or knockout diminishes the expression of gasdermins C2, C3 and C4, and concomitantly increases the activated forms of caspases 3, 8 and 9 as well as the number of TUNEL-positive apoptotic cells in the proximal colon. Together, our data suggest that taste signal transduction pathways are not only involved in the detection of infection, but also contribute to helping maintain gasdermin expression and prevent apoptotic cell death in the proximal colon, and these findings provide another strategy to combat infection and sheds light on new roles of taste signaling proteins along with gasdermins in protecting the integrity of the proximal colonic epithelium.
Topics: Taste; Ruminococcus; Signal Transduction; Transient Receptor Potential Channels; Colon
PubMed: 37954611
DOI: 10.3389/fimmu.2023.1259521