Figure 4.

Regulation of Fucα1,2Gal-containing glycan production in the ileum of germ-free NMRI mice. (A) Representative whole-mount preparations of ileum obtained 10 days after inoculation of the indicated strain and stained with peroxidase-conjugated UEA-I (brown). Villi appear as finger-like projections. (B). Model for the coordinate regulation of bacterial fucose metabolism with host fucosylated glycan production. l-fucose acts through FucR both as the inducer of transcription of fucRIAK and as a corepressor of transcription at csp, which is directly or indirectly responsible for production of a bacterial signal that results in increased production of host fucosylated glycoconjugates.