Lacticaseibacillus paracasei completely utilizes fructooligosacchrides in the human gut through ß-fructosidase (FosE).

The fecal microbiota of two healthy adults was cultivated in a medium containing commercial fructooligosaccharides [FOS; 1-kestose (GF2), nystose (GF3), and 1F-fructofuranosylnystose (GF4)]. Initially, the proportions of lactobacilli in the two feces samples were only 0.42% and 0.17%; however, they significantly increased to 7.2% and 4.8%, respectively, after cultivation on FOS. Most FOS-utilizing isolates could utilize only GF2; however, Lacticaseibacillus paracasei strain Lp02 could fully consume GF3 and GF4 too. The FOS operon (fosRABCDXE) was present in Lc. paracasei Lp02 and another Lc. paracasei strain, KCTC 3510T, but fosE was only partially present in the non-FOS-degrading strain KCTC 3510T. In addition, the top six upregulated genes in the presence of FOS were fosABCDXE, particularly fosE. FosE is a ß-fructosidase that hydrolyzes both sucrose and all three FOS. Finally, a genome-based analysis suggested that fosE is mainly observed in Lc. paracasei, and only 13.5% (61/452) of their reported genomes were confirmed to include it. In conclusion, FosE allows the utilization of FOS, including GF3 and GF4 as well as GF2, by some Lc. paracasei strains, suggesting that this species plays a pivotal role in FOS utilization in the human gut.

Evaluation of fecal DNA extraction protocols for human gut microbiome studies.

BACKGROUND: DNA extraction is an important factor influencing the microbiome profile in fecal samples. Considering that the QIAamp DNA Stool Mini Kit, one of the most commonly used DNA extraction kits, is no longer manufactured, this study aimed to investigate whether a new commercially available kit, the QIAamp PowerFecal Pro DNA Kit, yields comparable microbiome profiles with those previously obtained using the QIAamp DNA Stool Mini Kit. RESULTS: We extracted DNA from fecal samples of 10 individuals using three protocols (protocol P of the QIAamp PowerFecal Pro DNA Kit, and protocols SB and S of the QIAamp DNA Stool Mini Kit with and without an additional bead-beating step, respectively) in triplicate. Ninety extracted DNA samples were subjected to 16S rRNA gene sequencing. DNA quality measured by 260/280 absorbance ratios was found to be optimal in protocol P. Additionally, the DNA quantity and microbiome diversity obtained using protocol P were significantly higher than those of protocol S, however, did not differ significantly from those of protocol SB. Based on the overall microbiome profiles, variations between protocol P and protocol SB or S were significantly less than between-individual variations. Furthermore, most genera were not differentially abundant in protocol P compared to the other protocols, and the number of differentially abundant genera, as well as the degree of fold-changes were smaller between protocols P and SB than between protocols P and S. CONCLUSIONS: The QIAamp PowerFecal Pro DNA Kit exhibited microbiome analysis results that were comparable with those of the QIAamp DNA Stool Mini Kit with a bead-beating step. These results will prove useful for researchers investigating the gut microbiome in selecting an alternative protocol to the widely used but discontinued kit.

Effects of Lactobacillus pentosus in Children with Allergen-Sensitized Atopic Dermatitis.

BACKGROUND: Recent studies have shown that oral administration of probiotics may improve the immune imbalance caused by dysbiosis of the gut microbiome in atopic dermatitis (AD). This study aimed to investigate the clinical and immunological effects of Lactobacillus pentosus in children with mild to moderate AD. METHODS: Children aged 2-13 years with AD were randomized to receive either 1.0 × 1010 colony-forming units of L. pentosus or placebo, daily, for 12 weeks. The clinical severity of AD and transepidermal water loss were evaluated. Blood eosinophil counts, serum total immunoglobulin E (IgE), and cytokine levels were measured. The diversity and composition of the gut microbiota were also analyzed. RESULTS: Eighty-two children were recruited, and 41 were assigned to the probiotics intervention group. The mean scoring of atopic dermatitis (SCORAD) indices at baseline were 30.4 and 34.3 for the probiotics and placebo groups, respectively. At week 12, the mean indices were 23.6 and 23.1 for the probiotics and placebo groups, respectively. Clinical severity decreased significantly over time in both groups, with no significant difference between the two groups. In both groups, there were no significant differences in cytokine levels, microbial diversity, or the relative abundance of the gut microbiota at week 12 compared with the corresponding baseline values. The mean subjective scores of SCORAD indices after intervention for the probiotics group were significantly lower than those for the placebo group in IgE sensitized AD (P = 0.019). CONCLUSION: Our results show improved symptoms in the probiotics and placebo groups, and we could not find additional effects of L. pentosus in AD. However, the mean subjective scores of SCORAD indices for the probiotics group are significantly improved compared with those for the placebo group in allergen-sensitized AD.

Diverse Distribution of Resistomes in the Human and Environmental Microbiomes.

The routine therapeutic use of antibiotics has caused resistance genes to be disseminated across microbial populations. In particular, bacterial strains having antibiotic resistance genes are frequently observed in the human microbiome. Moreover, multidrug-resistant pathogens are now widely spread, threatening public health. Such genes are transferred and spread among bacteria even in different environments. Advances in high throughput sequencing technology and computational algorithms have accelerated investigation into antibiotic resistance genes of bacteria. Such studies have revealed that the antibiotic resistance genes are located close to the mobility-associated genes, which promotes their dissemination. An increasing level of information on genomic sequences of resistome should expedite research on drug-resistance in our body and environment, thereby contributing to the development of public health policy. In this review, the high prevalence of antibiotic resistance genes and their exchange in the human and environmental microbiome is discussed with respect to the genomic contents. The relationships among diverse resistomes, related bacterial species, and the antibiotics are reviewed. In addition, recent advances in bioinformatics approaches to investigate such relationships are discussed.

The effect of heritability and host genetics on the gut microbiota and metabolic syndrome.

OBJECTIVE: Metabolic syndrome (MetS) arises from complex interactions between host genetic and environmental factors. Although it is now widely accepted that the gut microbiota plays a crucial role in host metabolism, current knowledge on the effect of host genetics on specific gut microbes related to MetS status remains limited. Here, we investigated the links among host genetic factors, gut microbiota and MetS in humans. DESIGN: We characterised the gut microbial community composition of 655 monozygotic (n=306) and dizygotic (n=74) twins and their families (n=275), of which approximately 18% (121 individuals) had MetS. We evaluated the association of MetS status with the gut microbiota and estimated the heritability of each taxon. For the MetS-related and heritable taxa, we further investigated their associations with the apolipoprotein A-V gene (APOA5) single nucleotide polymorphism (SNP) rs651821, which is known to be associated with triglyceride levels and MetS. RESULTS: Individuals with MetS had a lower gut microbiota diversity than healthy individuals. The abundances of several taxa were associated with MetS status; Sutterella, Methanobrevibacter and Lactobacillus were enriched in the MetS group, whereas Akkermansia, Odoribacter and Bifidobacterium were enriched in the healthy group. Among the taxa associated with MetS status, the phylum Actinobacteria, to which Bifidobacterium belongs, had the highest heritability (45.7%). Even after adjustment for MetS status, reduced abundances of Actinobacteria and Bifidobacterium were significantly linked to the minor allele at the APOA5 SNP rs651821. CONCLUSIONS: Our results suggest that an altered microbiota composition mediated by a specific host genotype can contribute to the development of MetS.

Enhancement of enteric adenovirus cultivation in a novel Ras-overexpressing cell line.

Enteric human adenoviruses (HAdVs; serotypes 40 and 41) have been identified as an emerging cause of drinking water contamination. Due to their fastidious characteristics, HAdVs are difficult to cultivate and therefore not detected easily by standard mammalian cell cultivation methods. Here we found that human embryonic kidney 293 cells, transformed transiently with Ras, enhanced HAdV replication by more than threefold. We also constructed a stable cell line overexpressing the Ras protein, 293-Ras, in which the replication of three HAdV strains of serotypes 40 and 41 was increased markedly. However, only HAdV replication was enhanced; infection of 293 and 293-Ras cells with human rhinivorus-6 showed no significant differences in replication rate. Infected 293-Ras cells exhibited an increased level and phosphorylation of extracellular regulated kinase (ERK). In addition, the Ras-mediated increase in HAdV replication was impaired by the mitogen-activated protein kinase/ERK kinase (MEK1) inhibitor U0126, suggesting direct involvement of the MEK1/ERK pathway in enhanced HAdV replication. Based on these results, we suggest that the 293-Ras cell line be used for the efficient detection and cultivation of HAdV strains in both clinical and environmental specimens.

Fecal Microbial Dysbiosis is Associated with Colorectal Cancer Risk in a Korean Population.

Purpose: The association between the fecal microbiota and colorectal cancer (CRC) risk has been suggested in epidemiologic studies. However, data from large-scale population-based studies are lacking. Materials and Methods: In this case-control study, we recruited 283 CRC patients from the Center for Colorectal Cancer, National Cancer Center Hospital, Korea to perform 16S rRNA gene sequencing of fecal samples. A total of 283 age- and sex-matched healthy participants were selected from 890 cohort of healthy Koreans that are publicly available (PRJEB33905). The microbial dysbiosis index (MDI) was calculated based on the differentially abundant species. The association between MDI and CRC risk was observed using conditional logistic regression. Sparse Canonical Correlation Analysis was performed to integrate species data with microbial pathways obtained by PICRUSt2. Results: There is a significant divergence of the microbial composition between CRC patients and controls (PERMANOVA p=0.001). Those who were in third tertile of the MDI showed a significantly increased risk of CRC in the total population (OR: 6.93, 95% CI: 3.98-12.06, p-trend<0.001) compared to those in the lowest tertile. Similar results were found for men (OR: 6.28, 95% CI: 3.04-12.98-, p-trend<0.001) and women (OR: 7.39, 95% CI: 3.10-17.63, p-trend<0.001). Bacteroides coprocola and Bacteroides plebeius species and 12 metabolic pathways were interrelated in healthy controls that explain 91% covariation across samples. Conclusion: Dysbiosis in the fecal microbiota may be associated with an increased risk of CRC. Due to the potentially modifiable nature of the gut microbiota, our findings may have implications for CRC prevention among Koreans.

Gut microbiome in healthy aging versus those associated with frailty.

As the proportion of older people in the world's population steadily increases, there is an urgent need to identify ways to support healthy aging. The gut microbiome has been proposed to be involved in aging-related diseases and has become an attractive target for improving health in older people. Herein, we cover the relationship between the gut microbiome and chronological age in adults, and then, we discuss the gut microbiome features associated with frailty, as a hallmark of unhealthy aging in older people. Furthermore, we describe the effects of microbiome-targeted interventions, such as dietary patterns and consumption of probiotics, prebiotics, and synbiotics, on modulating the gut microbiome composition and further promoting healthy aging. Further studies are needed to explore the underlying mechanisms of gut microbiome-induced aging complications and to develop personalized microbiome-based strategies for reducing the severity of frailty or preventing the onset of frailty in older adults.

Oral microbiome correlates with selected clinical biomarkers in individuals with no significant systemic disease.

The oral microbiome is an important component of the microbiome in the human body. Although the association of the oral microbiome with various diseases, including periodontitis and cancer, has been reported, information on how the oral microbiome is related to health-related indicators in healthy populations is still insufficient. In this study, we examined the associations of the oral microbiome with 15 metabolic and 19 complete blood count (CBC)-based markers in 692 healthy Korean individuals. The richness of the oral microbiome was associated with four CBC markers and one metabolic marker. Compositional variation in the oral microbiome was significantly explained by four markers: fasting glucose, fasting insulin, white blood cell count, and total leukocyte count. Furthermore, we found that these biomarkers were associated with the relative abundances of numerous microbial genera, such as Treponema, TG5, and Tannerella. By identifying the relationship between the oral microbiome and clinical biomarkers in a healthy population, our study presents a direction for future studies on oral microbiome-based diagnosis and interventions.

Effects of adsorption onto silica sand particles on the hydrolysis of tetracycline antibiotics.

Due to high usage of tetracycline antibiotics, concerns have been raised about their environmental fate. In this study, potential changes in the pseudo-first-order hydrolysis rate constants for three tetracyclines, tetracycline (TC), oxytetracycline (OTC) and chlortetracycline (CTC), were evaluated by measuring the rate constants in batch and column leaching experiments. The first-order hydrolysis rate constants were measured at pH 5, 7, and 9 using batch tests. The values were highest at pH 7 for all three tetracyclines (0.0030 ± 0.0004, 0.0042 ± 0.0001, and 0.0323 ± 0.0003 h(-1) for TC, OTC, and CTC, respectively), indicating relatively short environmental half-lives of tetracyclines. Interestingly, it was found that the rates of degradation of the parent tetracyclines were much faster when silica sand was present in a batch solution or when the solution was passed through a silica column. For example, the ratios of the first-order degradation rate constants obtained in the column experiments to those in batch experiments were 13.2, 2.1, and 2.0 for TC, OTC, and CTC at a volumetric flow rate of 0.08 mL h(-1), with an observed tendency for this ratio to increase with an increased flow rate. This indicates that the silica surface may serve as a catalyst for hydrolysis and that the actual environmental half-lives of tetracycline antibiotics could be shorter than those estimated from laboratory hydrolysis rate constants using the standard batch protocol. Furthermore, the toxicity of the column effluent containing hydrolysis metabolites was assessed using bioluminescence inhibition in Vibrio fischeri. It was estimated that the toxicity of the metabolites of CTC was lower than that of their parent compound, whereas the toxicity of metabolites of TC and OTC was as high as or higher than that of their parent compounds.

A qRT-PCR Method Capable of Quantifying Specific Microorganisms Compared to NGS-Based Metagenome Profiling Data.

Metagenome profiling research using next-generation sequencing (NGS), a technique widely used to analyze the diversity and composition of microorganisms living in the human body, especially the gastrointestinal tract, has been actively conducted, and there is a growing interest in the quantitative and diagnostic technology for specific microorganisms. According to recent trends, quantitative real-time PCR (qRT-PCR) is still a considerable technique in detecting and quantifying bacteria associated with the human oral and nasal cavities, due to the analytical cost and time burden of NGS technology. Here, based on NGS metagenome profiling data produced by utilizing 100 gut microbiota samples, we conducted a comparative analysis for the identification and quantification of five bacterial genera (Akkermansia, Bacteroides, Bifidobacterium, Phascolarctobacterium, and Roseburia) within same metagenomic DNA samples through qRT-PCR assay in parallel. Genus-specific primers, targeting the particular gene of each genus for qRT-PCR assay, allowed a statistically consistent quantification pattern with the metagenome profiling data. Furthermore, results of bacterial identification through Sanger validation demonstrated the high genus-specificity of each primer set. Therefore, our study suggests that an approach to quantifying specific microorganisms by applying the qRT-PCR method can compensate for the concerns (potential issues) of NGS while also providing efficient benefits to various microbial industries.

Association Between Gut Microbiome and Frailty in the Older Adult Population in Korea.

Frailty is a common geriatric syndrome associated with the risk of adverse health outcomes. Recently, 2 key pathophysiological characteristics of frailty, altered energy metabolism and dysregulated immunity, have been reported to be associated with gut microbiome dysbiosis, indicating that the gut microbiome plays a role in frailty. However, few studies have directly examined the relationship between the gut microbiome and frailty. Here, we investigated the association of frailty measures with the gut microbiome using 16S rRNA gene sequencing data obtained from the fecal samples of 176 Korean older adults. Overall frailty was scored using the Korean Frailty Index (FI). Grip strength and Geriatric Depression Scale (GDS) scores were used as physical and mental frailty measures, respectively. In contrast to age, metabolic, and inflammatory biomarkers, the frailty measures were associated with interindividual variations in microbial composition (false discovery rate [FDR] < 0.2). Both FI and GDS scores were negatively associated with microbial diversity (FDR < 0.2). Frailty measures showed distinct associations with specific microbial taxa and metabolic functions. Particularly, the Bacteroides enterotype was found only in subjects categorized in the frail group. Moreover, we observed that the abundance of beneficial taxa, such as Prevotella copri and Coprococcus eutactus, was reduced in frailer individuals, whereas that of detrimental taxa, such as Bacteroides fragilis and Clostridium hathewayi, was increased (FDR < 0.2). Our findings suggest that the gut microbiome can be used an indicator of an increased risk of frailty or a target for improving health in frail older adults.

Accuracy comparison study of new smartphone-based semen analyzer versus laboratory sperm quality analyzer.

PURPOSE: This study aimed to test the clinical efficacy of a portable smartphone-based App assisted semen analysis (SA) system, O'VIEW-M PRO® to clinically accurate in comparison with results of laboratory-based conventional semen analyses including manual microscopic and computer-assisted semen analysis (CASA) for self-evaluation of seminal parameters. MATERIALS AND METHODS: From January to May 2021, a total of 39 semen samples were analyzed for the sperm concentration and motility with new smartphone-based App assisted semen analyzer, O'VIEW-M PRO®, and results compared with those from laboratory-based manual microscopic SA with Makler Counting Chamber and CASA. RESULTS: The coefficient factors among the results of the measurement with Makler chamber and laboratory-based CASA comparing to O'VIEW-M PRO® were 0.666 and 0.655 for sperm density, 0.662 and 0.658 for sperm motility, respectively. There were no particular problems with clinical use of the O'VIEW-M PRO®. Device performance in classifying samples is positive (<15×106 sperm/mL) and negative (>15×106 sperm/mL) for sperm concentration criteria, and positive (<40%) and negative (>40%) for sperm motility criteria. The smartphone-based App assisted SA O'VIEW-M PRO® showed a sensitivity of 92.6%, a specificity of 66.7%, and overall accuracy rate of 84.6%. CONCLUSIONS: This study shows a novel smartphone-based App assisted SA system. O'VIEW-M PRO® can easily obtain semen parameter information through self-diagnosis at home and induce infertile men's treatment and help patients after receiving infertile men's treatment before receiving treatment.

Gut Microbiome Structure and Association with Host Factors in a Korean Population.

Characterizing the gut microbiome in the healthy population is the first step in elucidating its associations with host health conditions. Populations with different diet patterns, lifestyles, and genetic backgrounds harbor different gut microbes. In this study, we characterized the gut microbiome of 890 healthy Koreans using 16S rRNA sequencing. The Korean population harbored a relatively large fraction of the Prevotella enterotype and presented a distinctive gut microbiome, compared to that in the populations of other countries. Additionally, we determined the clusters of cooccurring microbes that were quantitatively correlated with each other. We found that microbe composition of the gut was strongly associated with age. We identified that the abundance of members of Bacteroidia and Clostridia differed with the host dietary patterns, body mass index, and stool frequency. The gut microbiome data obtained in this study would be an important resource for future studies addressing microbial contributions in health and disease. IMPORTANCE Comparing the gut microbiomes of healthy controls and disease patients showed that the composition of the gut microbiome is associated with various host health conditions. The gut microbiome in healthy Western populations is well characterized, while that of non-Western populations, with different diet patterns, lifestyles, and genetic backgrounds, is not clearly defined. In this study, we characterized the microbiome of 890 healthy Korean individuals using 16S rRNA sequencing and found that Koreans have a gut microbiome different from that in the individuals of neighboring countries. The members of Bacteroidetes and Firmicutes cooccurred and were quantitatively associated with each other. Additionally, we found that the gut microbial composition is strongly associated with the host's age. The microbiome data presented here represent the gut microbiome of a healthy Korean population and could be used to unveil gut microbiome-associated host conditions in this population.

Effect of Saengshik Supplementation on the Gut Microbial Composition of Healthy Korean Adults: A Single-Group Pilot Study.

Saengshik is a type of meal-replacement product or dietary supplement comprising an uncooked and dried plant-based food mixture with various health-promoting properties, such as antidiabetic, anti-dyslipidemic, antioxidant, and anticancer properties. Although these properties are considered attributable to the various bioactive components absorbed through the intestine and its remolding effect on intestinal microorganisms, the effect of Saengshik supplementation on gut microbiota profiles has not yet been studied. In this study, we investigated the effect of Saengshik administration on the composition of gut microbiota. This single-group design trial was conducted on 102 healthy men and women who received 40 g/day of Saengshik powder for 8 weeks, during which stool samples were collected at two fixed time points (baseline and the endpoint) for gut microbiota-profiling analysis. We observed a significant decrease in the α-diversity of gut microbiota after Saengshik consumption (P < 0.05), with significant changes identified in the composition of major microbial taxa, such as Bacteroidetes (P < 0.0001), Proteobacteria, Actinobacteria, and Verrucomicrobia (P < 0.0001). Notably, the gut microbial response was related to the inter-individual variability of habitual dietary intake and enterotype at baseline. To the best of our knowledge, this is the first study investigating the effects of Saengshik intake on changes in gut microbiota, with the results suggesting that individual habitual diet patterns and gut microbial shapes should be considered key aspects in Saengshik-mediated health-promotion effects.

The effect of taxonomic classification by full-length 16S rRNA sequencing with a synthetic long-read technology.

Characterizing the microbial communities inhabiting specimens is one of the primary objectives of microbiome studies. A short-read sequencing platform for reading partial regions of the 16S rRNA gene is most commonly used by reducing the cost burden of next-generation sequencing (NGS), but misclassification at the species level due to its length being too short to consider sequence similarity remains a challenge. Loop Genomics recently proposed a new 16S full-length-based synthetic long-read sequencing technology (sFL16S). We compared a 16S full-length-based synthetic long-read (sFL16S) and V3-V4 short-read (V3V4) methods using 24 human GUT microbiota samples. Our comparison analyses of sFL16S and V3V4 sequencing data showed that they were highly similar at all classification resolutions except the species level. At the species level, we confirmed that sFL16S showed better resolutions than V3V4 in analyses of alpha-diversity, relative abundance frequency and identification accuracy. Furthermore, we demonstrated that sFL16S could overcome the microbial misidentification caused by different sequence similarity in each 16S variable region through comparison the identification accuracy of Bifidobacterium, Bacteroides, and Alistipes strains classified from both methods. Therefore, this study suggests that the new sFL16S method is a suitable tool to overcome the weakness of the V3V4 method.

Enhancement of enteric adenovirus cultivation by viral transactivator proteins.

Human enteric adenoviruses (HAdVs; serotypes 40 and 41) are important waterborne and food-borne pathogens. However, HAdVs are fastidious, are difficult to cultivate, and do not produce a clear cytopathic effect during cell culture within a reasonable time. Thus, we examined whether the viral transactivator proteins cytomegalovirus (CMV) IE1 and hepatitis B virus (HBV) X promoted the multiplication of HAdVs. Additionally, we constructed a new 293 cell line expressing CMV IE1 protein for cultivation assays. We analyzed the nucleic acid sequences of the promoter regions of both E1A and hexon genes, which are considered to be the most important regions for HAdV replication. Expression of either HBV X or CMV IE1 protein significantly increased the promoter activities of E1A and hexon genes of HAdVs by as much as 14-fold during cell cultivation. The promotion of HAdV expression was confirmed by increased levels of both adenoviral DNA and mRNA expression. Finally, the newly developed 293 cell line expressing CMV IE1 protein showed an increase in viral DNA ranging from 574% to 619% compared with the conventional 293 cell line. These results suggest that the newly constructed cell line could be useful for efficient cultivation and research of fastidious HAdVs.

Characterization of ozone disinfection of murine norovirus.

Despite the importance of human noroviruses (NoVs) in public health, little information concerning the effectiveness of ozone against NoVs is available. We determined the efficacy of ozone disinfection using murine norovirus (MNV) as a surrogate of human NoV. MNV in ozone demand-free buffer was exposed to a predetermined dose of ozone at two different pHs and temperatures. The virus remaining in the solution was analyzed by plaque assay, real-time TaqMan reverse transcriptase PCR (RT-PCR) (short template), and long-template conventional RT-PCR. Under all conditions, more than 99% of the MNV was inactivated by ozone at 1 mg/liter within 2 min. Both RT-PCR assays significantly underestimated the inactivation of MNV, compared with that measured by plaque assay. Our results indicate that NoV may be more resistant to ozone than has been previously reported. Nevertheless, proper ozone disinfection practices can be used to easily control its transmission in water.

Changes in microbiome and metabolomic profiles of fecal samples stored with stabilizing solution at room temperature: a pilot study.

The gut microbiome is related to various host health conditions through metabolites produced by microbiota. Investigating their relationships involves association analysis of the population-level microbiome and metabolome data, which requires the appropriate collection, handling, and storage of specimens. Simplification of the specimen handling processes will facilitate such investigations. As a pilot study for population-level studies, we collected the fecal samples from three volunteers and tested whether a single sample collection procedure, particularly using OMNIgene-GUT, can be used to reliably obtain both microbiome and metabolome data. We collected fecal samples from three young and healthy Korean adults, stored them at room temperature with and without OMNIgene-GUT solution up to three weeks, and analyzed their microbiome and metabolite profiles. We found that the microbiome profiles were stably maintained in OMNIgene-GUT solution for 21 days, and the abundance relationships among metabolites were well preserved, although their absolute abundances slightly varied over time. Our results show that a single sampling procedure suffices to obtain a fecal sample for collecting gut microbiome and gut metabolome data of an individual. We expect that the health effects of gut microbiome via fecal metabolites can be further understood by increasing the sampling size to the population level.

Roseburia spp. Abundance Associates with Alcohol Consumption in Humans and Its Administration Ameliorates Alcoholic Fatty Liver in Mice.

Although a link between the gut microbiota and alcohol-related liver diseases (ALDs) has previously been suggested, the causative effects of specific taxa and their functions have not been fully investigated to date. Here, we analyze the gut microbiota of 410 fecal samples from 212 Korean twins by using the Alcohol Use Disorders Identification Test (AUDIT) scales to adjust for host genetics. This analysis revealed a strong association between low AUDIT scores and the abundance of the butyrate-producing genus Roseburia. When Roseburia spp. are administered to ALD murine models, both hepatic steatosis and inflammation significantly improve regardless of bacterial viability. Specifically, the flagellin of R. intestinalis, possibly through Toll-like receptor 5 (TLR5) recognition, recovers gut barrier integrity through upregulation of the tight junction protein Occludin and helps to restore the gut microbiota through elevated expression of IL-22 and REG3γ. Our study demonstrates that Roseburia spp. improve the gut ecosystem and prevent leaky gut, leading to ameliorated ALDs.