Actinomyces tissue specificity may depend on differences in receptor specificity for GalNAc beta-containing glycoconjugates.
AUTOR(ES)
Strömberg, N
RESUMO
Actinomyces naeslundii 12104 and A. viscosus LY7 were compared for receptor specificities and adherence properties because these relate to their oral colonization sites. Both strains bind GalNAc beta-containing glycosphingolipids (GSLs) in a GalNAc beta 1-3Gal alpha Oethyl-sensitive fashion but differ with respect to the number of cells bound to GSLs and the effect of neighboring sugar groups on the binding. Their hemagglutination and saccharide inhibition profiles confirms the existence of two receptor specificities (for example, when GalNAc beta 1-3Gal alpha Oethyl is multivalently conjugated to albumin, its inhibitory activity increases fourfold toward strain 12104 but decreases fourfold toward strain LY7). Trypsin or chymotrypsin treatment of human erythrocytes, which possess receptor GSLs, improves their hemagglutination with strain 12104. In contrast, the same treatment of chicken erythrocytes, which lack receptor GSLs, abolishes their hemagglutination. These findings suggest that both GSLs and glycoproteins act as functional receptors on eukaryotic cells. The strains also differ with respect to the following GalNAc beta 1-3Gal alpha Oethyl-sensitive adherence properties: (i) strain LY7 adheres somewhat better than does strain 12104 to buccal epithelial cells; (ii) in spite of their similar overall coaggregation patterns with streptococci, strain 12104 coaggregates with Streptococcus oralis MPB1 but strain LY7 does not; (iii) strain 12104 alone shows GalNAc beta-sensitive saliva aggregation and adherence to saliva-coated hydroxyapatite. The GSL binding patterns of fresh Actinomyces isolates reveal a high prevalence of LY7-like specificities among buccal isolates, whereas 12104-like specificities are most prevalent among plaque isolates. These findings strongly suggest that fresh Actinomyces isolates use fine specificity for GalNAc beta-containing glycoconjugates in recognition and subsequent colonization of specific oral surfaces.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=257311Documentos Relacionados
- Salivary receptors for GalNAc beta-sensitive adherence of Actinomyces spp.: evidence for heterogeneous GalNAc beta and proline-rich protein receptor properties.
- Binding of the fibrillar CS3 adhesin of enterotoxigenic Escherichia coli to rabbit intestinal glycoproteins is competitively prevented by GalNAc beta 1-4Gal-containing glycoconjugates.
- Alpha-lactalbumin affects the acceptor specificity of Lymnaea stagnalis albumen gland UDP-GalNAc:GlcNAc beta-R beta 1-->4-N-acetylgalactosaminyltransferase: synthesis of GalNAc beta 1-->4Glc.
- Attachment of Escherichia coli via mannose- or Gal alpha 1----4Gal beta-containing receptors to human colonic epithelial cells.
- Many pulmonary pathogenic bacteria bind specifically to the carbohydrate sequence GalNAc beta 1-4Gal found in some glycolipids.