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Background: Inflammatory bowel disease (IBD) refers to a diverse group of chronic gastrointestinal diseases, and gut microbial dysbiosis has been proposed as a modulating factor in its pathogenesis. Several studies have investigated the gut microbial ecology of dogs with IBD but it is yet unclear if this microbial profile can alter the nutrient metabolism of the host. The aim of the present study was to characterize the faecal bacterial profile and functionality as well as to determine host metabolic changes in IBD dogs. Twenty-three dogs diagnosed with IBD and ten healthy control dogs were included. Dogs with IBD were given a clinical score using the canine chronic enteropathy clinical activity index (CCECAI). Faecal short-chain fatty acids (SCFA) and ammonia concentrations were measured and quantitative PCR was performed. The concentration of plasma amino acids, acylcarnitines, serum folate, cobalamin, and indoxyl sulfate was determined. Results: No significant differences in the abundance of a selection of bacterial groups and fermentation metabolites were observed between the IBD and control groups. However, significant negative correlations were found between CCECAI and the faecal proportion of Lactobacillus as well as between CCECAI and total SCFA concentration. Serum folate and plasma citrulline were decreased and plasma valine was increased in IBD compared to control dogs. Increased plasma free carnitine and total acylcarnitines were observed in IBD compared with control dogs, whereas short-chain acylcarnitines (butyrylcarnitine + isobutyrylcarnitine and, methylmalonylcarnitine) to free carnitine ratios decreased. Dogs with IBD had a higher 3-hydroxyisovalerylcarnitine + isovalerylcarnitine to leucine ratio compared to control dogs. Conclusions: Canine IBD induced a wide range of changes in metabolic profile, especially for the plasma concentrations of short-chain acylcarnitines and amino acids, which could have evolved from tissue damage and alteration in host metabolism. In addition, dogs with more severe IBD were characterised by a decrease in faecal proportion of Lactobacillus. [ABSTRACT FROM AUTHOR]

Butyrate-producing bacteria are promising probiotic candidates to target microbial dysbiosis in gastrointestinal disorders like inflammatory bowel diseases. Butyricicoccus pullicaecorum 25-3T, a butyrate-producing clostridial cluster IV strain, is such a candidate. Little is known about its abundance in the colon microbiota and its butyrogenic properties. We used the M-SHIMER® , an in vitro simulator for the human intestinal microbial ecosystem, to study the effect of supplementing a single dose of B. pullicaecorum 25-3T on lumen- and mucus-associated microbiota of eight individuals. Butyricicoccus pullicaecorum was more abundant in mucus-associated microbiota compared with lumen microbiota. Supplementation with a single dose of B. pullicaecorum 25-3T resulted in a temporary increase in B. pullicaecorum bacteria in lumen compartment of all individuals. In two cases, the responders, an increased butyrate production was observed as compared with the control. 16S rRNA gene amplicon sequencing revealed the microbiota of responders to be different as compared to non-responder microbiota. We can conclude that B. pullicaecorum 25-3T is a mucus-associated bacterium whose potency to stimulate butyrate production is characterized by a large interindividual variability in terms of composition of the receiving microbial community. [ABSTRACT FROM AUTHOR]

A response from the authors of the article "Butyricicoccus pullicaecorum in inflammatory bowel disease" that was published in the 2013 issue is presented.

To avoid detrimental interactions with intestinal microbes, the human epithelium is covered with a protective mucus layer that traps host defence molecules. Microbial properties such as adhesion to mucus further result in a unique mucosal microbiota with a great potential to interact with the host. As mucosal microbes are difficult to study in vivo, we incorporated mucin-covered microcosms in a dynamic in vitro gut model, the simulator of the human intestinal microbial ecosystem (SHIME). We assessed the importance of the mucosal environment in this M-SHIME (mucosal-SHIME) for the colonization of lactobacilli, a group for which the mucus binding domain was recently discovered. Whereas the two dominant resident Lactobacilli, Lactobacillus mucosae and Pediococcus acidilactici, were both present in the lumen, L. mucosae was strongly enriched in mucus. As a possible explanation, the gene encoding a mucus binding (mub) protein was detected by PCR in L. mucosae. Also the strongly adherent Lactobacillus rhamnosus GG (LGG) specifically colonized mucus upon inoculation. Short-term assays confirmed the strong mucin-binding of both L. mucosae and LGG compared with P.acidilactici. The mucosal environment also increased long-term colonization of L. mucosae and enhanced its stability upon antibiotic treatment (tetracycline, amoxicillin and ciprofloxacin). Incorporating a mucosal environment thus allowed colonization of specific microbes such as L. mucosae and LGG, in correspondence with the in vivo situation. This may lead to more in vivo-like microbial communities in such dynamic, long-term in vitro simulations and allow the study of the unique mucosal microbiota in health and disease., (© 2011 The Authors; Microbial Biotechnology © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.)

Five isolates that produced large amounts of butyrate were obtained in the course of a study on the butyrate-producing microbiota from the caecal content of a 4-week-old broiler chicken. The five isolates were virtually indistinguishable in biochemical and genetic terms, suggesting that they were derived from a single bacterial clone colonizing this habitat. A phylogenetic analysis based on 16S rRNA gene sequences demonstrated that the five isolates represented a unique lineage within the Clostridium leptum subgroup of the clostridia, with Eubacterium desmolans as the closest phylogenetic neighbour (about 93 % similarity). These data indicate that the five novel isolates represent a single novel species within a novel genus, for which we propose the name Butyricicoccus pullicaecorum gen. nov., sp. nov. The type strain of Butyricicoccus pullicaecorum is 25-3(T) (=LMG 24109(T) =CCUG 55265(T)). The DNA G+C content of strain 25-3(T) was 54.5 mol% .