Distribution, organization and expression of genes concerned with anaerobic lactate utilization in human intestinal bacteria.

Lactate accumulation in the human gut is linked to a range of deleterious health impacts. However, lactate is consumed and converted to the beneficial short-chain fatty acids butyrate and propionate by indigenous lactate-utilizing bacteria. To better understand the underlying genetic basis for lactate utilization, transcriptomic analyses were performed for two prominent lactate-utilizing species from the human gut, and , during growth on lactate, hexose sugar or hexose plus lactate.

Maturation of Gut Microbiota and Circulating Regulatory T Cells and Development of IgE Sensitization in Early Life.

Recent studies suggest that the cross-talk between the gut microbiota and human immune system during the first year of life is an important regulator of the later development of atopic diseases. We explored the changes in the gut microbiota, blood regulatory T cells, and atopic sensitization in a birth-cohort of Estonian and Finnish children followed from 3 to 36 months of age. We describe here an infant Treg phenotype characterized by high Treg frequency, the maturation of Treg population characterized by a decrease in their frequency accompanied with an increase in the highly activated Treg cells.

The Human Gut Microbiota.

The microbiota in our gut performs many different essential functions that help us to stay healthy. These functions include vitamin production, regulation of lipid metabolism and short chain fatty acid production as fuel for epithelial cells and regulation of gene expression. There is a very numerous and diverse microbial community present in the gut, especially in the colon, with reported numbers of species that vary between 400 and 1500, for some those we even do not yet have culture representatives.

Faecalibacterium prausnitzii A2-165 has a high capacity to induce IL-10 in human and murine dendritic cells and modulates T cell responses.

Faecalibacterium prausnitzii strain A2-165 was previously reported to have anti-inflammatory properties and prevent colitis in a TNBS model. We compared the immunomodulatory properties of strain A2-165 to four different F. prausnitzii isolates and eight abundant intestinal commensals using human dendritic cells (DCs) and mouse BMDCs in vitro.

A simple coculture system shows mutualism between anaerobic faecalibacteria and epithelial Caco-2 cells.

Most gut bacteria are obligate anaerobes and are important for human health. However, little mechanistic insight is available on the health benefits of specific anaerobic gut bacteria. A main obstacle in generating such knowledge is the lack of simple and robust coculturing methods for anaerobic bacteria and oxygen-requiring human cells.

Proton pump inhibitors affect the gut microbiome.

Background And Aims: Proton pump inhibitors (PPIs) are among the top 10 most widely used drugs in the world. PPI use has been associated with an increased risk of enteric infections, most notably Clostridium difficile. The gut microbiome plays an important role in enteric infections, by resisting or promoting colonisation by pathogens.

Intestinal microbiota and anastomotic leakage of stapled colorectal anastomoses: a pilot study.

Background: Anastomotic leakage (AL) after colorectal surgery is a severe complication, resulting in morbidity, reinterventions, prolonged hospital stay and, in some cases, death. Some technical and patient-related aetiological factors of AL are well established. In many cases, however, none of these factors seem to explain the occurrence of AL.

Faecalibacterium prausnitzii Strain HTF-F and Its Extracellular Polymeric Matrix Attenuate Clinical Parameters in DSS-Induced Colitis.

A decrease in the abundance and biodiversity of intestinal bacteria within the Firmicutes phylum has been associated with inflammatory bowel disease (IBD). In particular, the anti-inflammatory bacterium Faecalibacterium prausnitzii, member of the Firmicutes phylum and one of the most abundant species in healthy human colon, is underrepresented in the microbiota of IBD patients. The aim of this study was to investigate the immunomodulatory properties of F.

Biofilm formation on the Provox ActiValve: Composition and ingrowth analyzed by Illumina paired-end RNA sequencing, fluorescence in situ hybridization, and confocal laser scanning microscopy.

Background: The most frequent cause of voice prosthesis failure is microbial biofilm formation on the silicone valve, leading to destruction of the material and transprosthetic leakage. The Provox ActiValve valve is made of fluoroplastic, which should be insusceptible to destruction. The purpose of this study was to determine if fluoroplastic is insusceptible to destruction by Candida species.

Substantial decreases in the number and diversity of microbiota during chemotherapy-induced gastrointestinal mucositis in a rat model.

Purpose: Earlier, we showed in acute myeloid leukemia (AML) patients that the microbiota changes dramatically during anticancer treatment, coinciding with gastrointestinal mucositis: The commensal anaerobic populations reduce in favor of potential pathogens. Therefore, interventions targeting the microbiota during mucositis might be interesting but can better be tested in animals than in vulnerable mucositis patients. Here, we aimed to study the potential microbial changes during methotrexate (MTX)-induced gastrointestinal mucositis in a well-established rat model and to study whether this model can be used for future microbial intervention studies.

The ATG16L1-T300A allele impairs clearance of pathosymbionts in the inflamed ileal mucosa of Crohn's disease patients.

Objective: Crohn's disease (CD) is caused by a complex interplay among genetic, microbial and environmental factors. ATG16L1 is an important genetic factor involved in innate immunity, including autophagy and phagocytosis of microbial components from the gut. We investigated the effect of inflammation on the composition of microbiota in the ileal mucosa of CD patients in relation to the ATG16L1 risk status.

Functional metabolic map of Faecalibacterium prausnitzii, a beneficial human gut microbe.

The human gut microbiota plays a central role in human well-being and disease. In this study, we present an integrated, iterative approach of computational modeling, in vitro experiments, metabolomics, and genomic analysis to accelerate the identification of metabolic capabilities for poorly characterized (anaerobic) microorganisms. We demonstrate this approach for the beneficial human gut microbe Faecalibacterium prausnitzii strain A2-165.

Bacillus anthracis-like bacteria and other B. cereus group members in a microbial community within the International Space Station: a challenge for rapid and easy molecular detection of virulent B. anthracis.

For some microbial species, such as Bacillus anthracis, the etiologic agent of the disease anthrax, correct detection and identification by molecular methods can be problematic. The detection of virulent B. anthracis is challenging due to multiple virulence markers that need to be present in order for B.

Aberrant gut microbiota composition at the onset of type 1 diabetes in young children.

Aims/hypothesis: Recent studies indicate that an aberrant gut microbiota is associated with the development of type 1 diabetes, yet little is known about the microbiota in children who have diabetes at an early age. To this end, the microbiota of children aged 1-5 years with new-onset type 1 diabetes was compared with the microbiota of age-matched healthy controls.

Methods: A deep global analysis of the gut microbiota composition was established by phylogenetic microarray analysis using a Human Intestinal Tract Chip (HITChip).

The HMI™ module: a new tool to study the Host-Microbiota Interaction in the human gastrointestinal tract in vitro.

Background: Recent scientific developments have shed more light on the importance of the host-microbe interaction, particularly in the gut. However, the mechanistic study of the host-microbe interplay is complicated by the intrinsic limitations in reaching the different areas of the gastrointestinal tract (GIT) in vivo. In this paper, we present the technical validation of a new device--the Host-Microbiota Interaction (HMI) module--and the evidence that it can be used in combination with a gut dynamic simulator to evaluate the effect of a specific treatment at the level of the luminal microbial community and of the host surface colonization and signaling.

Antioxidants keep the potentially probiotic but highly oxygen-sensitive human gut bacterium Faecalibacterium prausnitzii alive at ambient air.

The beneficial human gut microbe Faecalibacterium prausnitzii is a 'probiotic of the future' since it produces high amounts of butyrate and anti-inflammatory compounds. However, this bacterium is highly oxygen-senstive, making it notoriously difficult to cultivate and preserve. This has so far precluded its clinical application in the treatment of patients with inflammatory bowel diseases.

Oral cavity anaerobic pathogens in biofilm formation on voice prostheses.

Background: A polymerase chain reaction (PCR)-based method has been used to identify oral anaerobic pathogens in biofilms on voice prostheses. The purpose of the present study was to determine the location of those pathogens inside the biofilms.

Methods: Biofilms of 15 voice prostheses were sampled and used to identify the oral pathogens.

Porphyromonas Gingivalis and E-coli induce different cytokine production patterns in pregnant women.

Objective: Pregnant individuals of many species, including humans, are more sensitive to various bacteria or their products as compared with non-pregnant individuals. Pregnant individuals also respond differently to different bacteria or their products. Therefore, in the present study, we evaluated whether the increased sensitivity of pregnant women to bacterial products and their heterogeneous response to different bacteria was associated with differences in whole blood cytokine production upon stimulation with bacteria or their products.

Real-time in vivo imaging of invasive- and biomaterial-associated bacterial infections using fluorescently labelled vancomycin.

Invasive and biomaterial-associated infections in humans are often difficult to diagnose and treat. Here, guided by recent advances in clinically relevant optical imaging technologies, we explore the use of fluorescently labelled vancomycin (vanco-800CW) to specifically target and detect infections caused by Gram-positive bacteria. The application potential of vanco-800CW for real-time in vivo imaging of bacterial infections is assessed in a mouse myositis model and a human post-mortem implant model.

Topography of distinct Staphylococcus aureus types in chronic wounds of patients with epidermolysis bullosa.

The opportunistic pathogen Staphylococcus aureus is known to interfere with wound healing and represents a significant risk factor for wound infections and invasive disease. It is generally assumed that one individual is predominantly colonized by one S. aureus type.

Fecal microbiota composition differs between children with β-cell autoimmunity and those without.

The role of the intestinal microbiota as a regulator of autoimmune diabetes in animal models is well-established, but data on human type 1 diabetes are tentative and based on studies including only a few study subjects. To exclude secondary effects of diabetes and HLA risk genotype on gut microbiota, we compared the intestinal microbiota composition in children with at least two diabetes-associated autoantibodies (n = 18) with autoantibody-negative children matched for age, sex, early feeding history, and HLA risk genotype using pyrosequencing. Principal component analysis indicated that a low abundance of lactate-producing and butyrate-producing species was associated with β-cell autoimmunity.

Cytokine production induced by non-encapsulated and encapsulated Porphyromonas gingivalis strains.

Objective: Although the exact reason is not known, encapsulated gram-negative Porphyromonas gingivalis strains are more virulent than non-encapsulated strains. Since difference in virulence properties may be due to difference in cytokine production following recognition of the bacteria or their products by the host inflammatory cells, we compared cytokine production following stimulation with bacteria or lipopolysaccharides (LPS) of a non-encapsulated and an encapsulated P. gingivalis strain (K(-) and K1).

How can Faecalibacterium prausnitzii employ riboflavin for extracellular electron transfer?

Faecalibacterium prausnitzii is one of the most abundant commensal microbes in the human gut. It is an important supplier of butyrate to the colonic epithelium, and low numbers of faecalibacteria have been associated with severe inflammatory bowel disease. Previous studies revealed that F.

The gut anaerobe Faecalibacterium prausnitzii uses an extracellular electron shuttle to grow at oxic-anoxic interphases.

Faecalibacterium prausnitzii is one of the most abundant bacteria in the human gut ecosystem and it is an important supplier of butyrate to the colonic epithelium. Low numbers of faecalibacteria have been associated with inflammatory bowel disease. Despite being extremely oxygen sensitive, F.