Glycolipid binding epitopes involved in adherence of the periodontitis-associated bacterium Porphyromonas gingivalis

Abstract

The ability of the periodontal pathogen Porphyromonas gingivalis to use different glycolipid structures as receptors has previously been demonstrated. The bacterium adhered to acid and nonacid glycolipids originating from human organs and to nonacid glycolipids of porcine origin. The aim of the present study was to analyze these binding epitopes by structural characterization. Glycolipid fractions with positive bacterial binding from e.g. human and porcine origin, were purified by the high performance liquid chromatography technique and thereafter used in bacterial overlay assays with (35)S-labeled P. gingivalis. Purified fractions with positive binding were structurally characterized by proton nuclear magnetic resonance spectroscopy. Complementing thin-layer chromatograms and bacterial overlay assays with pure reference glycolipid fractions and competition experiments with lactose were performed to define potential receptors. The P. gingivalis binding epitopes, including cerebrosides with nonhydroxy fatty acids, lactosylceramide with hydroxy fatty acids, sulfatides, lacto-, neolacto- and gangliotetraosylceramides, are in several instances similar to those found for other bacteria, e.g. H. pylori, H. influenzae and N. meningitidis. In addition P. gingivalis also bound to the Galalpha4Gal epitope of the globo series of glycolipids. In the future these results may be valuable for development of new treatment strategies, such as anti-adhesion therapies and vaccines specifically directed against P. gingivalis infection.

Structural Complexity of Non-acid Glycosphingolipids in Human Embryonic Stem Cells Grown under Feeder-free Conditions

“…Table 3. Fraction 121:I thus contains two monohexosylceramide species identified as Glc␤1Cer (structure 1) (ϳ90%) and Gal␤1Cer (structure 2) (ϳ10%) from the positions of the anomeric resonances at 4.075 and 4.024 ppm, respectively (25). The glucose is corroborated by the observation of its H2 resonance at 2.996 ppm (data not shown).…”

“…The subsequent fraction (121:II) displays anomeric resonances from three different glycosphingolipids: globotriaosylceramide (structure 5) (ϳ45%), as evidenced by resonances at 4.780 ppm (Gal␣4), 4.246 ppm (Gal␤4), and 4.157 ppm (Glc␤1); galabiaosylceramide (structure 4) (ϳ10%) with anomeric resonances at 4.814 ppm (Gal␣4) and 4.098 ppm (Gal␤1); and finally, lactosylceramide (structure 3) (ϳ45%) with resonances at 4.195 (Gal␤4) and 4.155 ppm (Glc␤1), the latter completely overlapping the corresponding globotriaosylceramide resonance (25,26). In fraction 121:III, only one additional compound is evident, namely globotetraosylceramide (structure 6), whose minor resonances (ϳ5% of the dominating globotriaosylceramide contribution) are found at 4.797 ppm (Gal␣4), 4.514 ppm (GalNAc␤3), 4.26 ppm (Gal␤4), and 4.16 ppm (Glc␤1) (25).…”

“…In fraction 121:III, only one additional compound is evident, namely globotetraosylceramide (structure 6), whose minor resonances (ϳ5% of the dominating globotriaosylceramide contribution) are found at 4.797 ppm (Gal␣4), 4.514 ppm (GalNAc␤3), 4.26 ppm (Gal␤4), and 4.16 ppm (Glc␤1) (25). Both fractions 121:II and 121:III have ceramides with sphingosine long-chain bases and non-hydroxy fatty acids, and fraction 121:II has more cis unsaturation than fraction 121: III.…”

Sialic acid, periodontal pathogens and Tannerella forsythia: stick around and enjoy the feast!

“…, 2011) whereas pretreatment of human cells with sialidase or incubation with sialic acid reduces invasion (Agnani et al. , 2000; Hallen et al. , 2008).…”

Binding of the periodontitis associated bacterium Porphyromonas gingivalis to glycoproteins from human epithelial cells

“…Furthermore, we have shown that P. gingivalis can bind to both acidic and non‐acidic glycolipid fractions from a variety of organs of human and porcine origin, with a preference for sulfated glycolipids (11). We have also shown a preference for P. gingivalis to bind to cerebroside with non‐hydroxy fatty acid, as compared with gastrointestinal bacteria, which prefer hydroxy fatty acid (10). The aim of this present study was to investigate the ability of the periodontal pathogen P. gingivalis to adhere to glycoconjugates on intact cells and to glycoprotein preparations of epithelial cells.…”