• adhesins;
  • glycoconjugate receptors;
  • viridans group streptococci

The binding of 10 viridans group streptococci to sialic acid-, galactose (Gal)- and N-acetylgalactosamine (GalNAc)-containing receptors was defined by analysis of the interactions between these bacteria and structurally defined glycoconjugates, host cells and other streptococci. All interactions with sialic acid-containing receptors were Ca2+-independent as they were not affected by ethyleneglycoltetraacetic acid (EGTA), whereas all interactions with Gal- and GalNAc-containing receptors were Ca2+-dependent. Recognition of sialic acid-, Gal- and GalNAc-containing receptors varied widely among the strains examined, in a manner consistent with the association of each of the three lectin-like activities with a different bacterial cell surface component.