Next generation of probiotic bacteria: The test case of bifidobacteria

Bacteria reside in a myriad of ecological niches. The human gut is among the most densely populated habitats, where a plethora of microorganisms are believed to have coevolved to beneficially influence the health status of their human host. In this book chapter, we discuss several fascinating interactions such as pili- as well as exopolysaccaride-mediated interplay that exist between the mammalian gastrointestinal tract and its resident bifidobacteria, as a model group of probiotic human enteric microorganisms. Thus, we propose that the identification of the genetic strategies followed by bifidobacteria to colonize and persist within the human gut might represent a novel way for the selection of the next generation of probiotic bifidobacteria.