Mass spectral evidence for N-glycans with branching on fucose in a molluscan hemocyanin
Gielens, C.; Idakieva, K.; Van den Bergh, V.; Siddiqui, N.I.; Parvanova, K.; Compernolle, F. (2005). Mass spectral evidence for N-glycans with branching on fucose in a molluscan hemocyanin. Biochem. Biophys. Res. Commun. 331(2): 562-570. https://dx.doi.org/10.1016/j.bbrc.2005.03.217 In: Biochemical and Biophysical Research Communications. ACADEMIC PRESS INC ELSEVIER SCIENCE: San Diego etc.. ISSN 0006-291X; e-ISSN 1090-2104, more | |
Keywords | Gastropoda [WoRMS]; Mollusca [WoRMS]; Rapana thomasiana Crosse, 1861 [WoRMS] Marine/Coastal | Author keywords | deglycosylation; electrospray ionization mass spectrometry; fucose; gaschromatography; gastropod; hemocyanin; mollusc; MS/MS; N-glycosylation;Rapana thomasiana |
Authors | | Top | - Gielens, C., more
- Idakieva, K.
- Van den Bergh, V.
| - Siddiqui, N.I.
- Parvanova, K.
- Compernolle, F.
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Abstract | Glycopeptides, isolated from a trypsinolysate of functional unit (FU) RtH2-e of Rapana thomasiana hemocyanin subunit 2, were analysed by electrospray ionization mass spectrometry and MS/MS. From the molecular mass observed after deglycosylation, it was inferred that all glycopeptides shared the same peptide stretch 92–143 of FU RtH2-e with a glycosylation site at Asn-127. Besides the core structure Man3GlcNAc2 for N-glycosylation, structures with a supplementary GlcNAc linked to either the Man(α1–3) or the Man(α1–6) arm and/or an additional tetrasaccharide unit connected to the other Man arm were observed, indicating the existence of microheterogeneity at the glycan level. The tetrasaccharide unit contains a central fucose moiety substituted with 3-O-methylgalactose and N-acetylgalactosamine, and linked to GlcNAc at the reducing end. This structure represents a novel N-glycan motif and is likely to be immunogenic. A second potential site for N-glycosylation in FU RtH2-e at Asn-17 was shown to be not glycosylated. |
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