In IBD the dominant fecal microbiota comprises unusual bacterial species. Moreover, CD and UC fecal microbiota harbor specific discrepancies and differ from that of IC and healthy subjects.

The composition of the colonic microbiota of 91 northern Europeans was characterized by fluorescent in situ hybridization using 18 phylogenetic probes. On average 75% of the bacteria were identified, and large interindividual variations were observed. Clostridium coccoides and Clostridium leptum were the dominant groups (28.0% and 25.2%), followed by the Bacteroides (8.5%). According to principal component analysis, no significant grouping with respect to geographic origin, age, or gender was observed.For the past 10 years, the progress made in molecular technologies has given rise to new ways to explore the human colonic microbiota. Investigations based on 16S rRNA sequences have revealed the presence of hundreds of molecular species, the majority uncultivated and/or not yet cultivated, unique to their host and with few species shared between two individuals (5, 10, 13). Fluorescent in situ hybridization (FISH) (1) of the 16S rRNA has shown that the species diversity comprised less than 20 dominant phylogenetic groups (2-4, 7). However, the molecular analysis has so far been restricted to limited cohorts of individuals, recruited within a single geographic region or country (3,4,7,8,14). In this study, we characterized the fecal microbiota of 91 individuals from five northern European countries to provide a large-scale molecular analysis of the normal colonic microbiota in healthy humans. Multivariate data analysis was performed in order to seek a possible link between the composition of the fecal microbiota and age, gender, or geographic origin parameters.

BackgroundBACTIBASE is an integrated open-access database designed for the characterization of bacterial antimicrobial peptides, commonly known as bacteriocins.DescriptionFor its second release, BACTIBASE has been expanded and equipped with additional functions aimed at both casual and power users. The number of entries has been increased by 44% and includes data collected from published literature as well as high-throughput datasets. The database provides a manually curated annotation of bacteriocin sequences. Improvements brought to BACTIBASE include incorporation of various tools for bacteriocin analysis, such as homology search, multiple sequence alignments, Hidden Markov Models, molecular modelling and retrieval through our taxonomy Browser.ConclusionThe provided features should make BACTIBASE a useful tool in food preservation or food safety applications and could have implications for the development of new drugs for medical use. BACTIBASE is available at http://bactibase.pfba-lab-tun.org.

The bacterial community, in whole or in part, resident in the bowel of humans is considered to fuel the chronic immune inflammatory conditions characteristic of Crohn's disease and ulcerative colitis. Chronic or recurrent pouchitis in ulcerative colitis patients is responsive to antibiotic therapy, indicating that bacteria are the etiological agents. Microbiological investigations of the bacterial communities in stool or of biopsy-associated bacteria have so far failed to reveal conclusively the existence of pathogens or bacterial communities of consistently altered composition in IBD patients relative to control subjects. Confounding factors need to be eliminated from future studies by using better-defined patient populations of newly diagnosed and untreated individuals and by improved sampling procedures.