Porphyromonas gingivalis fimbriae carbohydrate specificity assessment by glycomics.

Porphyromonas gingivalis is a major pathogen in adult periodontitis. Fimbriae play an important role in the initial interaction between the bacteria and the host. Our earlier studies suggested that the oligosaccharide moiety of lactoferrin is involved in the interaction with fimbriae. Porphyromonas gingivalis fimbriae bound strongly to albumin-fucosylamide (albumin-1-amido-1-deoxy-L-fucose) and to a lesser extent to albumin-N-acetyl-D-galactosamine (albumin-p-aminophenyl-N-acetyl-β-D-galactosaminide, but failed to bind bovine serum albumin. In this study we explored the glycan array to determine the carbohydrate-binding specificity of P. gingivalis fimbriae. Purified fimbriae bind to glycans which have a Lewis(x), Galβ1-4(Fucα1-3) GlcNAcβ structure in common. Interestingly, all glycans have a terminal fucose moiety and if fucose is removed, the fimbriae fail to bind. This is the first study that suggests that fucose is important for P. gingivalis fimbriae binding.