Identification of disulfide bonds and site-specific glycosylation in chicken alpha1-acid glycoprotein by matrix-assisted laser desorption ionization time-of-flight mass spectrometry.
Recently, we reported the amino acid sequence of chicken alpha1-acid glycoprotein (chicken alpha1-AGP) [Biochem. Biophys. Res. Commun. 295 (2002) 587]. In this study, we located the disulfide bonds and site-specific glycosylation in chicken alpha1-AGP using tryptic digests of carbamidomethylated chicken alpha1-AGP, carbamidomethylated completely deglycosylated chicken alpha1-AGP (cd-alpha1-AGP), and nonreduced denatured cd-alpha1-AGP by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Based on the detection of peptides mlz 3037.4 (amino acid sequences 69-76 plus 161-183) and 3453.3 (amino acid sequences 69-80 plus 161-183), the two disulfide bonds of chicken alpha1-AGP were determined to be located at Cys 6-Cys 146 and Cys 73-Cys 163. The results also showed that Asn 16, 70, 77, and 87 were fully glycosylated and that Asn 62 was partially glycosylated.
Matsunaga
Hisami
H
Faculty of Pharmaceutical Sciences, Mukogawa Women's University, 11-68 Koshien Kyuban-cho, Nishinomiya, Hyogo 663-8179, Japan.
Sadakane
Yutaka
Y
Haginaka
Jun
J
D000595:Amino Acid Sequence; D000818:Animals; D002645:Chickens; D002851:Chromatography, High Pressure Liquid; D004220:Disulfides / Q000737:chemistry*; D006031:Glycosylation; D008969:Molecular Sequence Data; D009961:Orosomucoid / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
D004220:Disulfides; D009961:Orosomucoid