Structural characterisation of N-linked and O-linked oligosaccharides derived from interferon-alpha2b and interferon-alpha14c produced by Sendai-virus-induced human peripheral blood leukocytes.
We have previously isolated and partially characterised the components of a highly purified interferon-alpha (IFN-alpha) preparation produced by Sendai-virus-induced human peripheral blood leukocytes. Nine IFN-alpha species were identified, and two of these were found to be glycosylated [Nyman, T. A., Tölö, H., Parkkinen, J. & Kalkkinen, N. (1998) Identification of nine interferon-alpha subtypes produced by Sendai-virus-induced human peripheral blood leukocytes, Biochem. J. 329, 295-302]. Here, we isolated the N-linked oligosaccharides of IFN-alpha14c and the O-linked chains of IFN-alpha2b, and the glycans were characterised by electrospray tandem mass spectrometry and by specific glycosidase digestions monitored by matrix-assisted laser desorption ionisation time of flight mass spectrometry. The IFN-alpha14c N-glycans were shown to exhibit core-fucosylated biantennary glycans, with about 10% carrying an additional alpha1,3-linked fucose unit at the antennae. The IFN-alpha2b was shown to carry about 50% core type-1 disialyltetrasaccharides, 30% core type-1 monosialyltrisaccharides and 20% core type-2 monosialylpentasaccharides.
Nyman
T A
TA
Institute of Biotechnology, Protein Chemistry Laboratory, University of Helsinki, Finland.
Kalkkinen
N
N
Tölö
H
H
Helin
J
J
D006031:Glycosylation; D006801:Humans; D016898:Interferon-alpha / Q000302:isolation & purification / Q000378:metabolism*; D007963:Leukocytes, Mononuclear / Q000378:metabolism* / Q000821:virology; D013058:Mass Spectrometry; D009844:Oligosaccharides / Q000737:chemistry* / Q000302:isolation & purification; D011134:Polysaccharides / Q000737:chemistry; D018108:Respirovirus
D016898:Interferon-alpha; D009844:Oligosaccharides; D011134:Polysaccharides