Purified plasma membranes were prepared from L1210 as ertes tumor cells and analyzed for their protein and carbohy drate composition. Conditions were developed for treating the isolated plasma membranes with Vibrio cholerae neuraminidase (VCN) so that 88% of the N-acetylneuraminic acid was removed without changing membrane proteins or other mem brane carbohydrate constituents. The VCN-induced m...

Vibrio cholerae neuraminidase (VCNA) plays a significant role in the pathogenesis of cholera by removing sialic acid from higher order gangliosides to unmask GM1, the receptor for cholera toxin. We previously showed that the structure of VCNA is composed of a central beta-propeller catalytic domain flanked by two lectin-like domains; however the nature of the carbohydrates recognized by these l...

The rotavirus spike protein domain VP8* is essential for recognition of cell surface carbohydrate receptors, notably those incorporating N-acylneuraminic acids (members of the sialic acid family). N-Acetylneuraminic acids occur naturally in both animals and humans, whereas N-glycolylneuraminic acids are acquired only through dietary uptake in normal human tissues. The preference of animal rotav...

With dimethyl sulphoxide instead of butanol in the thiobarbituric acid assay for sialic acid, a non-fading chromophore with lambdamax. = 549 nm was produced in a homogeneous solution, allowing dilution of the test mixture in case of high colour yield. This test adapted well to studies on alkaline de-O-acetylation. Bovine and rat submaxillary mucins, and rabbit Tamm-Horsfall urinary sialoprotein...

Group 2 coronaviruses are characterized within the order Nidovirales by a unique genome organization. A characteristic feature of group 2 coronaviruses is the presence of a gene encoding the haemagglutinin-esterase (HE) protein, which is absent in coronaviruses of groups 1 and 3. At least three coronavirus strains within group 2 expressed a structural protein with sialate-4-O-acetylesterase act...

Agglutinates of native chicken erythrocytes caused by influenza virus A/Aichi/2/68 (H3Nz) at 4 OC were potently fused and lysed at low pH (optimum pH 5.3) at 37 O C . Exogenous gangliosides GMs (Siaa2-3Galj314Glcfll-ceramide) and Gm (GalNAcfll-4(Siaa2-3)Gal#ll-4Glc@l-ceramide) were integrated into the membranes of chicken asialoerythrocytes within 5min incubation at 37 O C . We found that the...

A samarium-mediated Barbier reaction was performed to a€ord N-acetylneuraminic acid -Cglycosyl compounds (`` -C-glycosides'') in excellent yield. The neuraminic acid phenyl sulfone or 2-pyridyl sulfone derivatives reacted with ketones or aldehydes resulting in the instantaneous and stereospeci®c formation of Neu5Ac -C-glycosides. The phenyl and the 2-pyridyl sulfone derivatives were equally e€e...

We describe a synthetic sialic acid analogue, 9-thioacetamido-N-acetylneuraminic acid (9-thioacetamido-Neu5Ac), which is recognized by the receptor-binding activity of influenza C virus, but is resistant to the receptor-destroying enzyme (acetylesterase) of this virus. Following transfer of the analogue to the surface of receptor-negative cells, influenza C virus is able to attach to these cell...

Sialic acid-containing lipopolysaccharides (LPS) were isolated from six bacterial strains of the family Enterobacteriaceae. Sialic acid was released from permethylated LPS by methanolysis, and partially O-methylated N-acetyl-N-methyl-neuraminic acid methyl ester methyl glycosides were analyzed by gas-liquid chromatography-electron ionization mass spectrometry. It was proved that all LPS contain...