Disentangling the Relative Roles of Vertical Transmission, Subsequent Colonizations, and Diet on Cockroach Microbiome Assembly

ABSTRACT A multitude of factors affect the assemblies of complex microbial communities associated with animal hosts, with implications for community flexibility, resilience, and long-term stability; however, their relative effects have rarely been deduced. Here, we use a tractable lab model to quantify the relative and combined effects of parental transmission (egg case microbiome present/reduced), gut inocula (cockroach versus termite gut provisioned), and varying diets (matched or unmatched with gut inoculum source) on gut microbiota structure of hatchlings of the omnivorous cockroach Shelfordella lateralis using 16S rRNA gene (rDNA) amplicon sequencing. We show that the presence of a preexisting bacterial community via vertical transmission of microbes on egg cases reduces subsequent microbial invasion, suggesting priority effects that allow initial colonizers to take a strong hold and which stabilize the microbiome. However, subsequent inoculation sources more strongly affect ultimate community composition and their ecological networks, with distinct host-taxon-of-origin effects on which bacteria establish. While this is so, communities respond flexibly to specific diets in ways that consequently impact predicted community functions. In conclusion, our findings suggest that inoculations drive communities toward different stable states depending on colonization and extinction events, through ecological host-microbe relations and interactions with other gut bacteria, while diet in parallel shapes the functional capabilities of these microbiomes. These effects may lead to consistent microbial communities that maximize the extended phenotype that the microbiota provides the host, particularly if microbes spend most of their lives in host-associated environments. IMPORTANCE When host fitness is dependent on gut microbiota, microbial community flexibility and reproducibility enhance host fitness by allowing fine-tuned environmental tracking and sufficient stability for host traits to evolve. Our findings lend support to the importance of vertically transmitted early-life microbiota as stabilizers, through interactions with potential colonizers, which may contribute to ensuring that the microbiota aligns within host fitness-enhancing parameters. Subsequent colonizations are driven by microbial composition of the sources available, and we confirm that host-taxon-of-origin affects stable subsequent communities, while communities at the same time retain sufficient flexibility to shift in response to available diets. Microbiome structure is thus the result of the relative impact and combined effects of inocula and fluctuations driven by environment-specific microbial sources and digestive needs. These affect short-term community structure on an ecological time scale but could ultimately shape host species specificities in microbiomes across evolutionary time, if environmental conditions prevail.

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Disentangling the relative roles of vertical transmission, subsequent colonizations and diet on cockroach microbiome assembly

10.1101/2020.07.01.183558 ◽

2020 ◽

Author(s):

Kristjan Germer ◽

Justinn Renelies-Hamilton ◽

David Sillam-Dussès ◽

Kasun H. Bodawatta ◽

Michael Poulsen

Keyword(s):

Gut Microbiota ◽

Microbial Communities ◽

Vertical Transmission ◽

Priority Effects ◽

Combined Effects ◽

Stable States ◽

Microbial Composition ◽

Host Fitness ◽

Microbial Invasion ◽

Host Taxon

AbstractA multitude of factors affect the assemblies of complex microbial communities associated with animal hosts, with implications for community flexibility, resilience and long-term stability; however, their relative effects have rarely been deduced. Here, we use a tractable lab model to quantify the relative and combined effects of parental transmission (egg case microbiome present/reduced), gut inocula (cockroach vs. termite gut provisioned), and varying diets (matched with gut inoculum source) on gut microbiota structure of hatchlings of the omnivorous cockroach Shelfordella lateralis using 16S rDNA amplicon sequencing. We show that the presence of a pre-existing bacterial community via vertical transmission of microbes on egg cases reduces subsequent microbial invasion, suggesting priority effects that allow initial colonizers to take a stronghold and which stabilize the microbiome. However, the subsequent inoculation sources more strongly affect ultimate community composition, with distinct host-taxon-of-origin effects on which bacteria establish. While this is so, communities respond flexibly to specific diets that consequently strongly impact community functions predicted using PICRUSt2. In conclusion, our findings suggest that inoculations drive communities towards different stable states depending on colonization and extinction events, through ecological host-microbe relations and interactions with other gut bacteria, while diet in parallel shapes the functional capabilities of these microbiomes. These effects may lead to consistent microbial communities that maximize the extended phenotype that the microbiota provides the host, particularly if microbes spend most of their lives in host-associated environments.Contribution to the fieldWhen host fitness is dependent on gut microbiota, microbial community flexibility and reproducibility enhance host fitness by allowing fine-tuned environmental tracking and sufficient stability for host traits to evolve. Our findings lend support to the importance of vertically transmitted early-life microbiota as stabilizers through interactions with potential colonizers that may contribute to ensuring that the microbiota aligns within host fitness-enhancing parameters. Subsequent colonizations are driven by microbial composition of the sources available, and we confirm that host-taxon-of-origin affects stable subsequent communities, while communities at the same time retain sufficient flexibility to shift in response to available diets. Microbiome structure is thus the result of the relative impact and combined effects of inocula and fluctuations driven by environment-specific microbial sources and digestive needs. These affect short-term community structure on an ecological time scale, but could ultimately shape host species specificities in microbiomes across evolutionary time, if environmental conditions prevail.

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Diversity, Composition and Functional Inference of Gut Microbiota in Indian Cabbage white Pieris canidia (Lepidoptera: Pieridae)

Life ◽

10.3390/life10110254 ◽

2020 ◽

Vol 10 (11) ◽

pp. 254

Author(s):

Ying Wang ◽

Jianqing Zhu ◽

Jie Fang ◽

Li Shen ◽

Shuojia Ma ◽

...

Keyword(s):

Gut Microbiota ◽

16S Rrna Gene Sequencing ◽

Adult Survival ◽

Rrna Gene ◽

Life Stages ◽

Microbial Composition ◽

Significant Difference ◽

Functional Inference ◽

Rrna Gene Sequencing ◽

Insect Fitness

We characterized the gut microbial composition and relative abundance of gut bacteria in the larvae and adults of Pieris canidia by 16S rRNA gene sequencing. The gut microbiota structure was similar across the life stages and sexes. The comparative functional analysis on P. canidia bacterial communities with PICRUSt showed the enrichment of several pathways including those for energy metabolism, immune system, digestive system, xenobiotics biodegradation, transport, cell growth and death. The parameters often used as a proxy of insect fitness (development time, pupation rate, emergence rate, adult survival rate and weight of 5th instars larvae) showed a significant difference between treatment group and untreated group and point to potential fitness advantages with the gut microbiomes in P. canidia. These data provide an overall view of the bacterial community across the life stages and sexes in P. canidia.

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Dissimilarity of microbial diversity of pond water, shrimp intestine and sediment in Aquamimicry system

AMB Express ◽

10.1186/s13568-020-01119-y ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Shenzheng Zeng ◽

Sukontorn Khoruamkid ◽

Warinphorn Kongpakdee ◽

Dongdong Wei ◽

Lingfei Yu ◽

...

Keyword(s):

Microbial Communities ◽

Well Being ◽

Pacific White Shrimp ◽

Shrimp Farming ◽

Rrna Gene ◽

Microbial Composition ◽

Shrimp Culture ◽

Water And Sediment ◽

Surrounding Environment ◽

Shrimp Production

Abstract The Pacific white shrimp, with the largest production in shrimp industry, has suffered from multiple severe viral and bacterial diseases, which calls for a more reliable and environmentally friendly system to promote shrimp culture. The “Aquamimicry system”, mimicking the nature of aquatic ecosystems for the well-being of aquatic animals, has effectively increased shrimp production and been adapted in many countries. However, the microbial communities in the shrimp intestine and surrounding environment that act as an essential component in Aquamimicry remain largely unknown. In this study, the microbial composition and diversity alteration in shrimp intestine, surrounding water and sediment at different culture stages were investigated by high throughput sequencing of 16S rRNA gene, obtaining 13,562 operational taxonomic units (OTUs). Results showed that the microbial communities in shrimp intestine and surrounding environment were significantly distinct from each other, and 23 distinguished taxa for each habitat were further characterized. The microbial communities differed significantly at different culture stages, confirmed by a great number of OTUs dramatically altered during the culture period. A small part of these altered OTUs were shared between shrimp intestine and surrounding environment, suggesting that the microbial alteration of intestine was not consistent with that of water and sediment. Regarding the high production of Aquamimicry farm used as a case in this study, the dissimilarity between intestinal and surrounding microbiota might be considered as a potential indicator for healthy status of shrimp farming, which provided hints on the appropriate culture practices to improve shrimp production.

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The Effects of Genetic Relatedness on the Preterm Infant Gut Microbiota

Microorganisms ◽

10.3390/microorganisms9020278 ◽

2021 ◽

Vol 9 (2) ◽

pp. 278

Author(s):

Shen Jean Lim ◽

Miriam Aguilar-Lopez ◽

Christine Wetzel ◽

Samia V. O. Dutra ◽

Vanessa Bray ◽

...

Keyword(s):

Gut Microbiota ◽

Preterm Infant ◽

Neonatal Intensive Care ◽

Genetic Relatedness ◽

Bovine Milk ◽

Alpha Diversity ◽

Neonatal Intensive Care Units ◽

Rrna Gene ◽

Microbial Composition ◽

Operational Taxonomic Units

The preterm infant gut microbiota is influenced by environmental, endogenous, maternal, and genetic factors. Although siblings share similar gut microbial composition, it is not known how genetic relatedness affects alpha diversity and specific taxa abundances in preterm infants. We analyzed the 16S rRNA gene content of stool samples, ≤ and >3 weeks postnatal age, and clinical data from preterm multiplets and singletons at two Neonatal Intensive Care Units (NICUs), Tampa General Hospital (TGH; FL, USA) and Carle Hospital (IL, USA). Weeks on bovine milk-based fortifier (BMF) and weight gain velocity were significant predictors of alpha diversity. Alpha diversity between siblings were significantly correlated, particularly at ≤3 weeks postnatal age and in the TGH NICU, after controlling for clinical factors. Siblings shared higher gut microbial composition similarity compared to unrelated individuals. After residualizing against clinical covariates, 30 common operational taxonomic units were correlated between siblings across time points. These belonged to the bacterial classes Actinobacteria, Bacilli, Bacteroidia, Clostridia, Erysipelotrichia, and Negativicutes. Besides the influence of BMF and weight variables on the gut microbial diversity, our study identified gut microbial similarities between siblings that suggest genetic or shared maternal and environmental effects on the preterm infant gut microbiota.

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Comparative Analysis of the Gut Microbiota of Adult Mosquitoes From Eight Locations in Hainan, China

Frontiers in Cellular and Infection Microbiology ◽

10.3389/fcimb.2020.596750 ◽

2020 ◽

Vol 10 ◽

Author(s):

Xun Kang ◽

Yanhong Wang ◽

Siping Li ◽

Xiaomei Sun ◽

Xiangyang Lu ◽

...

Keyword(s):

Gut Microbiota ◽

Disease Control ◽

Bacterial Communities ◽

Mosquito Species ◽

Microbial Community Composition ◽

Variable Region ◽

Rrna Gene ◽

Microbial Composition ◽

Quality Filtering ◽

And Function

The midgut microbial community composition, structure, and function of field-collected mosquitoes may provide a way to exploit microbial function for mosquito-borne disease control. However, it is unclear how adult mosquitoes acquire their microbiome, how the microbiome affects life history traits and how the microbiome influences community structure. We analyzed the composition of 501 midgut bacterial communities from field-collected adult female mosquitoes, including Aedes albopictus, Aedes galloisi, Culex pallidothorax, Culex pipiens, Culex gelidus, and Armigeres subalbatus, across eight habitats using the HiSeq 4000 system and the V3−V4 hyper-variable region of 16S rRNA gene. After quality filtering and rarefaction, a total of 1421 operational taxonomic units, belonging to 29 phyla, 44 families, and 43 genera were identified. Proteobacteria (75.67%) were the most common phylum, followed by Firmicutes (10.38%), Bacteroidetes (6.87%), Thermi (4.60%), and Actinobacteria (1.58%). The genera Rickettsiaceae (33.00%), Enterobacteriaceae (20.27%), Enterococcaceae (7.49%), Aeromonadaceae (7.00%), Thermaceae (4.52%), and Moraxellaceae (4.31%) were dominant in the samples analyzed and accounted for 76.59% of the total genera. We characterized the midgut bacterial communities of six mosquito species in Hainan province, China. The gut bacterial communities were different in composition and abundance, among locations, for all mosquito species. There were significant differences in the gut microbial composition between some species and substantial variation in the gut microbiota between individuals of the same mosquito species. There was a marked variation in different mosquito gut microbiota within the same location. These results might be useful in the identification of microbial communities that could be exploited for disease control.

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Deciphering Gut Microbiota Dysbiosis and Corresponding Genetic and Metabolic Dysregulation in Psoriasis Patients Using Metagenomics Sequencing

Frontiers in Cellular and Infection Microbiology ◽

10.3389/fcimb.2021.605825 ◽

2021 ◽

Vol 11 ◽

Author(s):

Shiju Xiao ◽

Guangzhong Zhang ◽

Chunyan Jiang ◽

Xin Liu ◽

Xiaoxu Wang ◽

...

Keyword(s):

Gut Microbiota ◽

Target Genes ◽

16S Rrna Gene Sequencing ◽

Rrna Gene ◽

Phosphotransferase System ◽

Microbial Composition ◽

Kegg Pathways ◽

Significant Difference ◽

Rrna Gene Sequencing ◽

Endothelial Growth Factor

BackgroundIncreasing evidence has shown that alterations in the intestinal microbiota play an important role in the pathogenesis of psoriasis. The existing relevant studies focus on 16S rRNA gene sequencing, but in-depth research on gene functions and comprehensive identification of microbiota is lacking.ObjectivesTo comprehensively identify characteristic gut microbial compositions, genetic functions and relative metabolites of patients with psoriasis and to reveal the potential pathogenesis of psoriasis.MethodsDNA was extracted from the faecal microbiota of 30 psoriatic patients and 15 healthy subjects, and metagenomics sequencing and bioinformatic analyses were performed. The Kyoto Encyclopedia of Genes and Genomes (KEGG) database, cluster of orthologous groups (COG) annotations, and metabolic analyses were used to indicate relative target genes and pathways to reveal the pathogenesis of psoriasis.ResultsCompared with healthy individuals, the gut microbiota of psoriasis patients displayed an alteration in microbial taxa distribution, but no significant difference in microbial diversity. A distinct gut microbial composition in patients with psoriasis was observed, with an increased abundance of the phyla Firmicutes, Actinobacteria and Verrucomicrobia and genera Faecalibacterium, Bacteroides, Bifidobacterium, Megamonas and Roseburia and a decreased abundance of the phyla Bacteroidetes, Euryarchaeota and Proteobacteria and genera Prevotella, Alistipes, and Eubacterium. A total of 134 COGs were predicted with functional analysis, and 15 KEGG pathways, including lipopolysaccharide (LPS) biosynthesis, WNT signaling, apoptosis, bacterial secretion system, and phosphotransferase system, were significantly enriched in psoriasis patients. Five metabolites, hydrogen sulfide (H2S), isovalerate, isobutyrate, hyaluronan and hemicellulose, were significantly dysregulated in the psoriatic cohort. The dysbiosis of gut microbiota, enriched pathways and dysregulated metabolites are relevant to immune and inflammatory response, apoptosis, the vascular endothelial growth factor (VEGF) signaling pathway, gut-brain axis and brain-skin axis that play important roles in the pathogenesis of psoriasis.ConclusionsA clear dysbiosis was displayed in the gut microbiota profile, genetic functions and relative metabolites of psoriasis patients. This study is beneficial for further understanding the inflammatory pathogenesis of psoriasis and could be used to develop microbiome-based predictions and therapeutic approaches.

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Altered Fecal Metabolites and Colonic Glycerophospholipids Were Associated With Abnormal Composition of Gut Microbiota in a Depression Model of Mice

Frontiers in Neuroscience ◽

10.3389/fnins.2021.701355 ◽

2021 ◽

Vol 15 ◽

Author(s):

Xue Gong ◽

Cheng Huang ◽

Xun Yang ◽

Jianjun Chen ◽

Juncai Pu ◽

...

Keyword(s):

Correlation Analysis ◽

Gut Microbiota ◽

16S Rrna Gene Sequencing ◽

Underlying Mechanism ◽

Rrna Gene ◽

Mice Model ◽

Microbial Composition ◽

Gas And Liquid Chromatography ◽

Correlation Analysis Method ◽

Rrna Gene Sequencing

The microbiota–gut–brain axis has been considered to play an important role in the development of depression, but the underlying mechanism remains unclear. The gastrointestinal tract is home to trillions of microbiota and the colon is considered an important site for the interaction between microbiota and host, but few studies have been conducted to evaluate the alterations in the colon. Accordingly, in this study, we established a chronic social defeated stress (CSDS) mice model of depression. We applied 16S rRNA gene sequencing to assess the gut microbial composition and gas and liquid chromatography–mass spectroscopy to identify fecal metabolites and colonic lipids, respectively. Meanwhile, we used Spearman’s correlation analysis method to evaluate the associations between the gut microbiota, fecal metabolites, colonic lipids, and behavioral index. In total, there were 20 bacterial taxa and 18 bacterial taxa significantly increased and decreased, respectively, in the CSDS mice. Further, microbial functional prediction demonstrated a disturbance of lipid, carbohydrate, and amino acid metabolism in the CSDS mice. We also found 20 differential fecal metabolites and 36 differential colonic lipids (in the category of glycerolipids, glycerophospholipids, and sphingolipids) in the CSDS mice. Moreover, correlation analysis showed that fecal metabolomic signature was associated with the alterations in the gut microbiota composition and colonic lipidomic profile. Of note, three lipids [PC(16:0/20:4), PG(22:6/22:6), and PI(18:0/20:3), all in the category of glycerophospholipids] were significantly associated with anxiety- and depression-like phenotypes in mice. Taken together, our results indicated that the gut microbiota might be involved in the pathogenesis of depression via influencing fecal metabolites and colonic glycerophospholipid metabolism.

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Exploring the role of gut microbiota in host feeding behavior among breeds in swine

BMC Microbiology ◽

10.1186/s12866-021-02409-6 ◽

2022 ◽

Vol 22 (1) ◽

Author(s):

Yuqing He ◽

Francesco Tiezzi ◽

Jeremy Howard ◽

Yijian Huang ◽

Kent Gray ◽

...

Keyword(s):

Gut Microbiota ◽

Feeding Behavior ◽

Growth Stages ◽

Rrna Gene ◽

Sequence Variants ◽

Host Feeding ◽

Microbial Composition ◽

Large White ◽

Rrna Gene Sequencing ◽

Host Metabolism

Abstract Background The interplay between the gut microbiota and feeding behavior has consequences for host metabolism and health. The present study aimed to explore gut microbiota overall influence on feeding behavior traits and to identify specific microbes associated with the traits in three commercial swine breeds at three growth stages. Feeding behavior measures were obtained from 651 pigs of three breeds (Duroc, Landrace, and Large White) from an average 73 to 163 days of age. Seven feeding behavior traits covered the information of feed intake, feeder occupation time, feeding rate, and the number of visits to the feeder. Rectal swabs were collected from each pig at 73 ± 3, 123 ± 4, and 158 ± 4 days of age. DNA was extracted and subjected to 16 S rRNA gene sequencing. Results Differences in feeding behavior traits among breeds during each period were found. The proportion of phenotypic variances of feeding behavior explained by the gut microbial composition was small to moderate (ranged from 0.09 to 0.31). A total of 21, 10, and 35 amplicon sequence variants were found to be significantly (q-value < 0.05) associated with feeding behavior traits for Duroc, Landrace, and Large White across the three sampling time points. The identified amplicon sequence variants were annotated to five phyla, with Firmicutes being the most abundant. Those amplicon sequence variants were assigned to 28 genera, mainly including Christensenellaceae_R-7_group, Ruminococcaceae_UCG-004, Dorea, Ruminococcaceae_UCG-014, and Marvinbryantia. Conclusions This study demonstrated the importance of the gut microbial composition in interacting with the host feeding behavior and identified multiple archaea and bacteria associated with feeding behavior measures in pigs from either Duroc, Landrace, or Large White breeds at three growth stages. Our study provides insight into the interaction between gut microbiota and feeding behavior and highlights the genetic background and age effects in swine microbial studies.

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Ontogenetic Differences in Dietary Fat Influence Microbiota Assembly in the Zebrafish Gut

mBio ◽

10.1128/mbio.00687-15 ◽

2015 ◽

Vol 6 (5) ◽

Cited By ~ 50

Author(s):

Sandi Wong ◽

W. Zac Stephens ◽

Adam R. Burns ◽

Keaton Stagaman ◽

Lawrence A. David ◽

...

Keyword(s):

Gut Microbiota ◽

Microbial Communities ◽

Dietary Fat ◽

Rrna Gene ◽

Microbiota Composition ◽

Ideal Model ◽

Surrounding Environment ◽

Animal Hosts ◽

The Relationship ◽

Gut Microbiota Composition

ABSTRACT Gut microbiota influence the development and physiology of their animal hosts, and these effects are determined in part by the composition of these microbial communities. Gut microbiota composition can be affected by introduction of microbes from the environment, changes in the gut habitat during development, and acute dietary alterations. However, little is known about the relationship between gut and environmental microbiotas or about how host development and dietary differences during development impact the assembly of gut microbiota. We sought to explore these relationships using zebrafish, an ideal model because they are constantly immersed in a defined environment and can be fed the same diet for their entire lives. We conducted a cross-sectional study in zebrafish raised on a high-fat, control, or low-fat diet and used bacterial 16S rRNA gene sequencing to survey microbial communities in the gut and external environment at different developmental ages. Gut and environmental microbiota compositions rapidly diverged following the initiation of feeding and became increasingly different as zebrafish grew under conditions of a constant diet. Different dietary fat levels were associated with distinct gut microbiota compositions at different ages. In addition to alterations in individual bacterial taxa, we identified putative assemblages of bacterial lineages that covaried in abundance as a function of age, diet, and location. These results reveal dynamic relationships between dietary fat levels and the microbial communities residing in the intestine and the surrounding environment during ontogenesis. IMPORTANCE The ability of gut microbiota to influence host health is determined in part by their composition. However, little is known about the relationship between gut and environmental microbiotas or about how ontogenetic differences in dietary fat impact gut microbiota composition. We addressed these gaps in knowledge using zebrafish, an ideal model organism because their environment can be thoroughly sampled and they can be fed the same diet for their entire lives. We found that microbial communities in the gut changed as zebrafish aged under conditions of a constant diet and became increasingly different from microbial communities in their surrounding environment. Further, we observed that the amount of fat in the diet had distinct age-specific effects on gut community assembly. These results reveal the complex relationships between microbial communities residing in the intestine and those in the surrounding environment and show that these relationships are shaped by dietary fat throughout the life of animal hosts.

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Probiotic Supplementation in a Clostridium difficile-Infected Gastrointestinal Model Is Associated with Restoring Metabolic Function of Microbiota

Microorganisms ◽

10.3390/microorganisms8010060 ◽

2019 ◽

Vol 8 (1) ◽

pp. 60

Author(s):

Mohd Baasir Gaisawat ◽

Chad W. MacPherson ◽

Julien Tremblay ◽

Amanda Piano ◽

Michèle M. Iskandar ◽

...

Keyword(s):

Gut Microbiota ◽

Alpha Diversity ◽

Gastrointestinal Disorder ◽

Short Chain Fatty Acids ◽

Rrna Gene ◽

Metabolic Function ◽

Microbial Composition ◽

Single Strain ◽

Fecal Samples ◽

Metabolic Functions

Clostridium (C.) difficile-infection (CDI), a nosocomial gastrointestinal disorder, is of growing concern due to its rapid rise in recent years. Antibiotic therapy of CDI is associated with disrupted metabolic function and altered gut microbiota. The use of probiotics as an adjunct is being studied extensively due to their potential to modulate metabolic functions and the gut microbiota. In the present study, we assessed the ability of several single strain probiotics and a probiotic mixture to change the metabolic functions of normal and C. difficile-infected fecal samples. The production of short-chain fatty acids (SCFAs), hydrogen sulfide (H2S), and ammonia was measured, and changes in microbial composition were assessed by 16S rRNA gene amplicon sequencing. The C. difficile-infection in fecal samples resulted in a significant decrease (p < 0.05) in SCFA and H2S production, with a lower microbial alpha diversity. All probiotic treatments were associated with significantly increased (p < 0.05) levels of SCFAs and restored H2S levels. Probiotics showed no effect on microbial composition of either normal or C. difficile-infected fecal samples. These findings indicate that probiotics may be useful to improve the metabolic dysregulation associated with C. difficile infection.

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