title: Mass Spectrometry and Two-Dimensional Electrophoresis To Characterize the Glycosylation of Hen Egg White Ovomacroglobulin.
abstract: Glycosylation of proteins plays an important role in their biological functions, such as allergenicity. Ovomacroglobulin (OVMG) is a glycoprotein from hen egg white, but few studies have been done so far to delineate the glycosylated sites of OVMG. The present study characterized the glycosylation of OVMG using mass spectrometry and two-dimensional electrophoresis. MALDI-TOF-MS showed that the OVMG subunit [M + H](+) ion has a peak at m/z 183297; therefore, the carbohydrate moiety is calculated as 11.5% of the whole OVMG molecule. HPLC-ESI-MS/MS confirmed that of 13 potential N-glycosylation sites of OVMG, 11 sites were glycosylated; 1 site (N(1221)) was found in both glycosylated and nonglycosylated forms. On the two-dimensional electrophoresis gel, a series of OVMG spots horizontally distributed at 170 kDa, with an isoelectric point range of 5.03-6.03, indicating the heterogeneity of glycosylation of OVMG. These results provided important information for understanding of structure, function, and potential allergenic sites of OVMG.
authors: National R&D Center for Egg Processing, College of Food Science and Technology, Huazhong Agricultural University , Wuhan 430070, China.
authors: Fang
authors: F
authors: Geng
authors: National R&D Center for Egg Processing, College of Food Science and Technology, Huazhong Agricultural University , Wuhan 430070, China.
authors: Xi
authors: X
authors: Huang
authors: Department of Food Science, University of Guelph , Guelph, Ontario N1G 2W1, Canada.
authors: Kaustav
authors: K
authors: Majumder
authors: National R&D Center for Egg Processing, College of Food Science and Technology, Huazhong Agricultural University , Wuhan 430070, China.
authors: Zhihui
authors: Z
authors: Zhu
authors: National R&D Center for Egg Processing, College of Food Science and Technology, Huazhong Agricultural University , Wuhan 430070, China.
authors: Zhaoxia
authors: Z
authors: Cai
authors: National R&D Center for Egg Processing, College of Food Science and Technology, Huazhong Agricultural University , Wuhan 430070, China.
authors: Meihu
authors: M
authors: Ma
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002241:Carbohydrates / Q000032:analysis; D002645:Chickens; D004529:Egg White / Q000737:chemistry*; D015180:Electrophoresis, Gel, Two-Dimensional / Q000379:methods*; D005260:Female; D006031:Glycosylation; D013058:Mass Spectrometry / Q000379:methods*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D000511:alpha-Macroglobulins / Q000737:chemistry*
chemical_list: D002241:Carbohydrates; D000511:alpha-Macroglobulins; C036828:ovomacroglobulin
keywords: egg white; glycosylation; mass spectrometry; ovomacroglobulin; two-dimensional electrophoresis