Biosynthesis of the common mammalian sialic acid N-glycolylneuraminic acid (Neu5Gc) was lost during human evolution due to inactivation of the CMAH gene, possibly expediting divergence of the Homo lineage, due to a partial fertility barrier. Neu5Gc catabolism generates N-glycolylhexosamines, which are potential precursors for glycoconjugate biosynthesis. We carried out metabolic labeling experi...

The physiological role of fungal galectins has remained elusive. Here, we show that feeding of a mushroom galectin, Coprinopsis cinerea CGL2, to Caenorhabditis elegans inhibited development and reproduction and ultimately resulted in killing of this nematode. The lack of toxicity of a carbohydrate-binding defective CGL2 variant and the resistance of a C. elegans mutant defective in GDP-fucose b...

Macular corneal dystrophy is a human genetic disorder characterized by corneal opacities that arise, in part, from a failure to synthesize mature keratan sulfate proteoglycans. The macromolecules in macular corneas and in keratoconus corneas, an abnormality not involving proteoglycans, were biosynthetically labeled with [3H]mannose and [14C]glucosamine in organ culture, and the keratan sulfate ...

Rapid waning of anti-polysaccharide bactericidal Ab and vaccine effectiveness is observed following infant immunization with the serogroup C meningococcal (MenC) glycoconjugate vaccine. This is despite the demonstrable presence of immunological memory. Persistence of functional Ab, therefore, appears to be the key determinant of MenC conjugate vaccine effectiveness. Ab persistence is thought to...

Red blood cell (RBC) membranes are rich in a glycoconjugate that is extractable in chloroform/methanol solutions (2/1, v/v) and contains several hexoses, such as glucose. Old and young RBC are separated and their respective glycoconjugates are prepared. HbA0 is purified by column chromatography and incubated with solutions of this conjugate. After 24-h incubation, Hb is dialyzed and the amount ...

The biological importance of lipopolysaccharides (LPS), components of bacterial cell wall has not been explained sufficiently. The glycine present in these structures could play an important role in the immunological response after bacterial infections and during sepsis. In our studies we obtained synthetic and stable substituted glycinated 1-thioglycosides derivatives of monosaccharides, e.g.,...

Leishmania promastigotes express an abundant cell surface glycoconjugate, lipophosphoglycan (LPG). LPG contains a polymer of the disaccharide-phosphate repeat unit Galbeta1,4Manalpha1-PO4, shared by other developmentally regulated molecules implicated in parasite virulence. Functional complementation of a Leishmania donovani LPG-defective mutant (OB1) accumulating a truncated LPG containing onl...

Mucus secreted onto the surface of the intestine forms a physical barrier to invading parasites so that a possible attachment of helminths to the surface is prevented and their expulsion by peristalsis facilitated. In mammals, intestinal parasites induce hyperplasia and hypertrophy of intestine goblet cells and provoke changes in the mucus composition. In fish, this topic has received less atte...

Distinct glycoconjugate expression between dome enterocytes and villus enterocytes in ileum from twelve 3-week-old conventional pigs was examined by the use of twenty one biotinylated lectins with avidin-biotin-peroxidase complex method. Three patterns of staining were seen. First, lectins bind to dome enterocyte and villus enterocyte to approximately equal staining, i.e. DSL, WGA, s-WGA and Co...

A self-consistent model of β-mannan oligosaccharides bound to a monoclonal antibody, C3.1, that protects mice against Candida albicans has been developed through chemical mapping, NMR spectroscopic, and computational studies. This antibody optimally binds di- and trisaccharide epitopes, whereas larger oligomers bind with affinities that markedly decrease with increasing chain length. The (1→2)-...