Genes involved in synthesis of lipoteichoic acids are induced when Bifidobacterium animalis subsp. lactis BB12 is incubated with Human Enterocyte-Like Caco-2 Cells

ABSTRACT: Bifidobacterium animalis subsp. lactis BB12 is a widely used probiotic bacterium. However the molecular mechanism by which this bacterium confers positive health effects to the host is largely unknown. The importance of lipoteichoic acids (LTA) in the cross-talk between the bacteria and human enterocyte-like Caco-2 cells was investigated in the present study. A microarray-based analysis of gene expression revealed induction of genes encoding enzymes involved in the synthesis of lipoteichoic acids of BB12. This observation was confirmed in phenotypic experiments, where a specific galactofuranosyl carbohydrate epitope present in the structure of lipoteichoic acids of BB12 was used as a detection marker. An exopolysaccharide EPS/LTA extract isolated from BB12 and commercially available pure LTAs from the human pathogen S. pyogenes were tested in competitive adhesion experiments. The adhesion of B. animalis subsp. lactis BB12 to Caco-2 cells was inhibited in presence of LTA. The strongest inhibition was observed in the concentration range 0.5-10 ug/ml for LTAs from S. pyogenes and 5-10 ug/ml for EPS/LTA extract from BB12. The inhibitory concentrations in both cases likely reflect the physico-chemical properties of LTAs with the highest efficacy below the critical micelle concentration, and therefore we ascribe the main inhibitory effect to LTAs for the BB12 isolated EPS/LTA extract as well. In conclusion we present increased biosynthesis of lipoteichoic acids of BB12 co-incubated with human Caco-2 cells and evidence that LTA serve as important cell wall factors involved in adhesion to these human enterocyte-like cells.

ORGANISM(S): Bifidobacterium animalis subsp. lactis BB-12 Bifidobacterium animalis subsp. lactis

PROVIDER: GSE21588 | GEO | 2012/08/01

SECONDARY ACCESSION(S): PRJNA127031

REPOSITORIES: GEO