title: Simultaneous identification of tyrosine phosphorylation and sulfation sites utilizing tyrosine-specific bromination.
abstract: Tyrosine phosphorylation and sulfation play many key roles in the cell. Isobaric phosphotyrosine and sulfotyrosine residues in peptides were determined by mass spectrometry using phosphatase or sulfatase to remove the phosphate or the sulfate group. Unique Br signature was introduced to the resulting tyrosine residues by incubation with 32% HBr at -20 °C for 20 min. MS/MS analysis of the brominated peptide enabled unambiguous determination of the phosphotyrosine and the sulfotyrosine sites. When phosphotyrosine and sulfotyrosine as well as free tyrosine were present in the same peptide, they could be determined simultaneously using either phosphatase or sulfatase following acetylation of the free tyrosine.
authors.affiliation: Department of Chemistry, Seoul National University, Seoul 151-742, Republic of Korea. jongseo.kim1@gmail.com
authors.forename: Jong-Seo
authors.initials: JS
authors.lastname: Kim
authors.forename: Si-Uk
authors.initials: SU
authors.lastname: Song
authors.forename: Hie-Joon
authors.initials: HJ
authors.lastname: Kim
mesh_terms: D020134:Catalytic Domain; D054879:Halogenation; D018054:Hydrobromic Acid / Q000737:chemistry; D010446:Peptide Fragments / Q000737:chemistry; D010449:Peptide Mapping; D010748:Phosphopeptides / Q000737:chemistry; D010744:Phosphoric Monoester Hydrolases / Q000737:chemistry; D019000:Phosphotyrosine / Q000737:chemistry*; D012710:Serum Albumin, Bovine / Q000737:chemistry; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013429:Sulfatases / Q000737:chemistry; D053719:Tandem Mass Spectrometry / Q000379:methods*; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000032:analysis / Q000737:chemistry / Q000378:metabolism
chemical_list: D010446:Peptide Fragments; D010748:Phosphopeptides; C475724:bromotyrosine; D019000:Phosphotyrosine; D012710:Serum Albumin, Bovine; C005662:tyrosine O-sulfate; D018054:Hydrobromic Acid; D014443:Tyrosine; D010744:Phosphoric Monoester Hydrolases; D013429:Sulfatases