Identification of N-glycans from Ebola virus glycoproteins by matrix-assisted laser desorption/ionisation time-of-flight and negative ion electrospray tandem mass spectrometry.

The larger fragment of the transmembrane glycoprotein (GP1) and the soluble glycoprotein (sGP) of Ebola virus were expressed in human embryonic kidney cells and the secreted products were purified from the supernatant for carbohydrate analysis. The N-glycans were released with PNGase F from within sodium dodecyl sulphate/polyacrylamide gel electrophoresis (SDS-PAGE) gels. Identification of the glycans was made with normal-phase high-performance liquid chromatography (HPLC), matrix-assisted laser desorption/ionisation mass spectrometry, negative ion electrospray ionisation fragmentation mass spectrometry and exoglycosidase digestion.

Identification of N-linked carbohydrates from severe acute respiratory syndrome (SARS) spike glycoprotein.

N-glycans were released from the SARS coronavirus (SARS-CoV) spike glycoprotein produced in Vero E6 cells and their structures were determined by a combination of matrix-assisted laser desorption/ionization (MALDI) mass spectrometry, negative ion electrospray collision-induced dissociation time-of-flight mass spectrometry and normal-phase high-performance liquid chromatography with exoglycosidase digestion. Major glycans were high-mannose (Man(5-9)GlcNAc(2)), hybrid and bi-, tri- and tetra-antennary complex with and without bisecting GlcNAc and core fucose. Complex glycans with fewer than the full complement of galactose residues were present and sialylation was negligible.

Inhibition of mammalian glycan biosynthesis produces non-self antigens for a broadly neutralising, HIV-1 specific antibody.

The HIV envelope has evolved a dense array of immunologically "self" carbohydrates that efficiently protect the virus from antibody recognition. Nonetheless, one broadly neutralising antibody, IgG1 2G12, has been shown to recognise a cluster of oligomannose glycans on the HIV-1 surface antigen gp120. Thus the self carbohydrates of HIV are now regarded as potential targets for viral neutralisation and vaccine design.

Monoglucosylated glycans in the secreted human complement component C3: implications for protein biosynthesis and structure.

The monoglucosylated oligomannose N-linked oligosaccharide (Glc(1)Man(9)GlcNAc(2)) is a retention signal for the calnexin-calreticulin quality control pathway in the endoplasmic reticulum. We report here the presence of such monoglucosylated N-glycans on the human complement serum glycoprotein C3. This finding represents the first report of monoglucosylated glycans on a human serum glycoprotein from non-diseased individuals.