title: Identification of O-phosphoamino acids in urine hydrolysate by gas chromatography-mass spectrometry.
abstract: The occurrence of O-phosphoserine (P-Ser), O-phosphothreonine (P-Thr) and O-phosphotyrosine (P-Tyr) in the hydrolysate of human urine was demonstrated. Urine samples were separated into non-adsorbed and adsorbed fractions by DEAE-cellulose column chromatography. After acid and base hydrolyses of these fractions, the O-phosphoamino acids in the hydrolysates were converted into their N-isobutoxycarbonyl methyl ester derivatives and identified by gas chromatography-mass spectrometry. By gas chromatography with flame photometric detection, the urinary contents of P-Ser, P-Thr and P-Tyr were estimated to be 945 +/- 3, 109 +/- 3 and 2.9 +/- 0.2 ng/ml, respectively.
authors.affiliation: Faculty of Pharmaceutical Sciences, Okayama University, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Kataoka
authors.forename: K
authors.initials: K
authors.lastname: Nakai
authors.forename: M
authors.initials: M
authors.lastname: Makita
mesh_terms: D000596:Amino Acids / Q000652:urine*; D002848:Chromatography, DEAE-Cellulose; D002849:Chromatography, Gas; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D006868:Hydrolysis; D010768:Phosphoserine / Q000652:urine; D010769:Phosphothreonine / Q000652:urine; D019000:Phosphotyrosine; D010783:Photometry; D014443:Tyrosine / Q000031:analogs & derivatives / Q000652:urine
chemical_list: D000596:Amino Acids; D010769:Phosphothreonine; D010768:Phosphoserine; D019000:Phosphotyrosine; D014443:Tyrosine