Fig. 2.

Bifidobacterial strategies to successfully colonize and survive in the human intestine. A schematic overview of the macromolecular structures exposed on the bifidobacterial surface and involved in host-microbe interactions are reported on the left: membrane protein (MP), exopolysaccharide (EPS), TgaA, wall and lipoteichoic acids (WTA and LTA) coupled with sortase-dependent and Tad pili. In addition, on the right, bifidobacterial degradative activities toward different diet- and host-derived complex carbohydrates are depicted. Hydrolysis of complex sugars by certain bifidobacterial species produces simple glycans that can be directly utilize as carbon sources by the same bifidobacterial species and/or metabolized by other members of the Bifidobacterium genus trough cross-feeding.