Analysis of hydroxyl radical-induced oxidation process of glucagon by reversed-phase HPLC and ESI-MS/MS

Biomed Chromatogr. 2009 Oct;23(10):1051-8. doi: 10.1002/bmc.1222.

Abstract

Structural modification of a polypeptide hormone, glucagon, by a hydroxyl radical in vitro was investigated by reversed-phase high-performance liquid chromatography (RP-HPLC), and the oxidized site of glucagon was detected by electrospray ionization tandem mass spectrometry (ESI-MS/MS). It was shown that (27)methionine (Met) was oxidized to (27)Met sulfoxide by hydroxyl radical, and the production rate of (27)Met sulfoxide was faster than that by hydrogen peroxide. In addition, production of (27)Met sulfoxide enantiomer was confirmed by RP-HPLC analysis. cAMP production in a HepG2 cell induced by (27)Met sulfoxide glucagon was reduced to approximately 75% as compared with that induced by the native form of glucagon.

MeSH terms

  • Cell Line, Tumor
  • Chromatography, High Pressure Liquid / methods*
  • Cyclic AMP / metabolism
  • Glucagon / analogs & derivatives*
  • Glucagon / analysis
  • Glucagon / chemistry
  • Glucagon / metabolism*
  • Hep G2 Cells
  • Humans
  • Hydrogen Peroxide / metabolism
  • Iron / metabolism
  • Linear Models
  • Methionine / metabolism
  • Oxidation-Reduction
  • Reactive Oxygen Species / metabolism
  • Safrole / analogs & derivatives
  • Safrole / metabolism
  • Spectrometry, Mass, Electrospray Ionization / methods
  • Stereoisomerism
  • Tandem Mass Spectrometry / methods*
  • Time Factors

Substances

  • Reactive Oxygen Species
  • glucagon, Met-sulfoxide(27)-
  • Glucagon
  • Methionine
  • Hydrogen Peroxide
  • Cyclic AMP
  • Iron
  • Safrole
  • sulfoxide