title: Glycoform analysis of Japanese cedar pollen allergen, Cry j 1.
abstract: In our previous study (Y. Kimura et al., Biosci. Biotechnol. Biochem., 69, 137-144 (2005)), we found that plant complex type N-glycans harboring Lewis a epitope are linked to the mountain cedar pollen allergen Jun a 1. Jun a 1 is a glycoprotein highly homologous with Japanese cedar pollen glycoallergen, Cry j 1. Although it has been found that some plant complex type N-glycans are linked to Cry j 1, the occurrence of Lewis a epitope in the N-glycan moiety has not been proved yet. Hence, we reinvestigated the glycoform of the pollen allergen to find whether the Lewis a epitope(s) occur in the N-glycan moiety of Cry j 1. From the cedar pollen glycoallergen, the N-glycans were liberated by hydrazinolysis and the resulting sugar chains were N-acetylated and then coupled with 2-aminopyridine. Three pyridylaminated sugar chains were purified by reversed-phase HPLC and size-fractionation HPLC. The structures were analyzed by a combination of exo- and endo-glycosidase digestions, sugar chain mapping, and electrospray ionization mass spectrometry (ESI-MS). Structural analysis clearly indicated that Lewis a epitope (Galbeta1-3(Fucalpha1-4)GlcNAcbeta1-), instead of the Galbeta1-4(Fucalpha1-6)GlcNAc, occurs in the N-glycans of Cry j 1.
authors.affiliation: Division of Biomolecular Science, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan.
authors.forename: Megumi
authors.initials: M
authors.lastname: Maeda
authors.forename: Maiko
authors.initials: M
authors.lastname: Kamamoto
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Hino
authors.forename: Shigeto
authors.initials: S
authors.lastname: Yamamoto
authors.forename: Mariko
authors.initials: M
authors.lastname: Kimura
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Okano
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Kimura
mesh_terms: D000485:Allergens / Q000032:analysis / Q000737:chemistry*; D052179:Antigens, Plant; D002240:Carbohydrate Sequence; D032485:Cryptomeria; D000939:Epitopes / Q000032:analysis / Q000737:chemistry; D006026:Glycoside Hydrolases / Q000378:metabolism; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000032:analysis / Q000737:chemistry*; D011058:Pollen / Q000737:chemistry*; D011134:Polysaccharides / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D000485:Allergens; D052179:Antigens, Plant; C065290:Cry j I protein, Cryptomeria japonica; D000939:Epitopes; D010940:Plant Proteins; D011134:Polysaccharides; C121951:jun a 1 protein, Juniperus ashei; D006026:Glycoside Hydrolases