title: Separation and identification of four distinct serine-phosphorylation states of ovalbumin by Phos-tag affinity electrophoresis.
abstract: Ovalbumin (OVA) derived from egg white contains two residues that can be phosphorylated: Ser-68 and Ser-344. Native polyacrylamide gel electrophoresis(PAGE) shows the presence of three distinct migration bands corresponding to phosphorylation states with two, one, or no phosphate groups, respectively. Phosphate-affinity sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE; Zn(2+)-Phos-tag SDS-PAGE), on the other hand, showed the presence of four distinct phosphorylated states in intact OVA. In addition to the diphosphorylated and nonphosphorylated forms, two distinct species, one with a phosphate group at Ser-68 and one with a phosphate group at Ser-344, were separately visualized. The content of the OVA monophosphorylated at Ser-68 was greater than that of OVA monophosphorylated at Ser-344. Zn(2+)-Phos-tag SDS-PAGE is therefore a useful method for the quantitative analysis of the detailed phosphorylation status of food proteins.
authors.affiliation: Department of Functional Molecular Science, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan.
authors.forename: Emiko
authors.initials: E
authors.lastname: Kinoshita-Kikuta
authors.forename: Eiji
authors.initials: E
authors.lastname: Kinoshita
authors.forename: Tohru
authors.initials: T
authors.lastname: Koike
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002645:Chickens; D015180:Electrophoresis, Gel, Two-Dimensional; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods*; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D010047:Ovalbumin / Q000737:chemistry*; D010750:Phosphoproteins / Q000737:chemistry*; D010766:Phosphorylation; D011725:Pyridines / Q000737:chemistry*; D012694:Serine / Q000737:chemistry*
chemical_list: C514153:1,3-bis(bis(pyridin-2-ylmethyl)amino)propan-2-ol; D010750:Phosphoproteins; D011725:Pyridines; D012694:Serine; D010047:Ovalbumin