Bifidobacteria of the Human Gut

Microorganisms live in a myriad of ecological niches. The human intestine is among the most densely populated environments; here, a multitude of bacteria appears to have co-evolved to beneficially impact on the health of their human host. In this chapter we discuss several fascinating relationships that exist between the mammalian gastrointestinal tract and its resident bifidobacteria, as a prototypical group of health-promoting human enteric microorganisms.