title: Electron spray ionization mass spectrometry and 2D 31P NMR for monitoring 18O/16O isotope exchange and turnover rates of metabolic oligophosphates.
abstract: A new method was here developed for the determination of (18)O-labeling ratios in metabolic oligophosphates, such as ATP, at different phosphoryl moieties (α-, β-, and γ-ATP) using sensitive and rapid electrospray ionization mass spectrometry (ESI-MS). The ESI-MS-based method for monitoring of (18)O/(16)O exchange was validated with gas chromatography-mass spectrometry and 2D (31)P NMR correlation spectroscopy, the current standard methods in labeling studies. Significant correlation was found between isotopomer selective 2D (31)P NMR spectroscopy and isotopomer less selective ESI-MS method. Results demonstrate that ESI-MS provides a robust analytical platform for simultaneous determination of levels, (18)O-labeling kinetics and turnover rates of α-, β-, and γ-phosphoryls in ATP molecule. Such method is advantageous for large scale dynamic phosphometabolomic profiling of metabolic networks and acquiring information on the status of probed cellular energetic system.
authors.affiliation: Division of Cardiovascular Diseases, Department of Medicine, Mayo Clinic, Rochester, MN 55905, USA. enemutlu@hacettepe.edu.tr
authors.forename: Emirhan
authors.initials: E
authors.lastname: Nemutlu
authors.forename: Nenad
authors.initials: N
authors.lastname: Juranic
authors.forename: Song
authors.initials: S
authors.lastname: Zhang
authors.forename: Lawrence E
authors.initials: LE
authors.lastname: Ward
authors.forename: Tumpa
authors.initials: T
authors.lastname: Dutta
authors.forename: K Sreekumaran
authors.initials: KS
authors.lastname: Nair
authors.forename: Andre
authors.initials: A
authors.lastname: Terzic
authors.forename: Slobodan
authors.initials: S
authors.lastname: Macura
authors.forename: Petras P
authors.initials: PP
authors.lastname: Dzeja
mesh_terms: D000255:Adenosine Triphosphate / Q000032:analysis / Q000378:metabolism*; D000818:Animals; D008401:Gas Chromatography-Mass Spectrometry; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D051379:Mice; D009206:Myocardium / Q000378:metabolism; D010103:Oxygen Isotopes / Q000032:analysis / Q000378:metabolism; D010710:Phosphates / Q000032:analysis / Q000378:metabolism*; D010759:Phosphorus Isotopes / Q000032:analysis / Q000378:metabolism; D051381:Rats; D021241:Spectrometry, Mass, Electrospray Ionization / Q000191:economics / Q000379:methods*
chemical_list: D010103:Oxygen Isotopes; D010710:Phosphates; D010759:Phosphorus Isotopes; D000255:Adenosine Triphosphate