title: N-Glycan structures of squid rhodopsin.
abstract: To determine the glycoforms of squid rhodopsin, N-glycans were released by glycoamidase A digestion, reductively aminated with 2-aminopyridine, and then subjected to 2D HPLC analysis [Takahashi, N., Nakagawa, H., Fujikawa, K., Kawamura, Y. & Tomiya, N. (1995) Anal. Biochem.226, 139-146]. The major glycans of squid rhodopsin were shown to possess the alpha1-3 and alpha1-6 difucosylated innermost GlcNAc residue found in glycoproteins produced by insects and helminths. By combined use of 2D HPLC, electrospray ionization-mass spectrometry and permethylation and gas chromatography-electron ionization mass spectrometry analyses, it was revealed that most (85%) of the N-glycans exhibit the novel structure Manalpha1-6(Manalpha1-3)Manbeta1-4GlcNAcbeta1-4(Galbeta1-4Fucalpha1-6)(Fucalpha1-3)GlcNAc.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Nagoya City University, Japan. ntakahas@phar.nagoya-cu.ac.jp
authors.forename: Noriko
authors.initials: N
authors.lastname: Takahashi
authors.forename: Katsuyoshi
authors.initials: K
authors.lastname: Masuda
authors.forename: Kenji
authors.initials: K
authors.lastname: Hiraki
authors.forename: Kazuo
authors.initials: K
authors.lastname: Yoshihara
authors.forename: Hung-Hsiang
authors.initials: HH
authors.lastname: Huang
authors.forename: Kay-Hooi
authors.initials: KH
authors.lastname: Khoo
authors.forename: Koichi
authors.initials: K
authors.lastname: Kato
mesh_terms: D000818:Animals; D002240:Carbohydrate Sequence; D049832:Decapodiformes / Q000737:chemistry*; D006023:Glycoproteins / Q000737:chemistry*; D008969:Molecular Sequence Data; D008974:Mollusca / Q000737:chemistry*; D009844:Oligosaccharides / Q000737:chemistry*; D011134:Polysaccharides / Q000737:chemistry*; D012243:Rhodopsin / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D006023:Glycoproteins; D009844:Oligosaccharides; D011134:Polysaccharides; D012243:Rhodopsin