| Autor: |
Pöltl G; Department für Chemie, Universität für Bodenkultur, Muthgasse 18, A-1190 Wien, Austria., Ahrazem O, Paschinger K, Ibañez MD, Salcedo G, Wilson IB |
| Jazyk: |
angličtina |
| Zdroj: |
Glycobiology [Glycobiology] 2007 Feb; Vol. 17 (2), pp. 220-30. Date of Electronic Publication: 2006 Nov 09. |
| DOI: |
10.1093/glycob/cwl068 |
| Abstrakt: |
The IgE of sera from patients with a history of allergy to oranges (Citrus sinensis) binds a number of proteins in orange extract, including Cit s 1, a germin-like protein. In the present study, we have analyzed its immunological cross-reactivity and its molecular nature. Sera from many of the patients examined recognize a range of glycoproteins and neoglycoconjugates containing beta1,2-xylose and core alpha1,3-fucose on their N-glycans. These reagents also inhibited the interaction of Cit s 1 with patients' sera, thus underlining the critical role of glycosylation in the recognition of this protein by patients' IgE and extending previous data showing that deglycosylated Cit s 1 does not possess IgE epitopes. In parallel, we examined the peptide sequence and glycan structure of Cit s 1, using mass spectrometric techniques. Indeed, we achieved complete sequence coverage of the mature protein compared with the translation of an expressed sequence tag cDNA clone and demonstrated that the single N-glycosylation site of this protein carries oligosaccharides with xylose and fucose residues. Owing to the presumed requirement for multivalency for in vivo allergenicity, our molecular data showing that Cit s 1 is monovalent as regards glycosylation and that the single N-glycan is the target of the IgE response to this protein explain the immunological cross-reactive properties of Cit s 1 as well as its equivocal nature as a clinically relevant allergen. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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