title: Carbon Isotopomer Analysis with Non-Unifom Sampling HSQC NMR for Cell Extract and Live Cell Metabolomics Studies.
abstract: Isotopomer analysis using either13C NMR or LC/GC-MS has been an invaluable tool for studying metabolic activities in a variety of systems. Traditional challenges are, however, that13C-detected NMR is insensitive despite its high resolution, and that MS-based techniques cannot easily differentiate positional isotopomers. In addition, current13C NMR or LC/GC-MS has limitations in detecting metabolites in living cells. Here, we describe a non-uniform sampling-based 2D heteronuclear single quantum coherence (NUS HSQC) approach to measure metabolic isotopomers in both cell lysates and living cells. The method provides a high resolution that can resolve multiplet structures in the13C dimension while retaining the sensitivity of the1H-indirect detection. The approach was tested in L1210 mouse leukemia cells labeled with13C acetate by measuring NUS HSQC with 25% sampling density. The results gave a variety of metabolic information such as (1) higher usage of acetate in acetylation pathway than aspartate synthesis, (2) TCA cycle efficiency changes upon the inhibition of mitochondrial oxidative phosphorylation by pharmacological agents, and (3) position-dependent isotopomer patterns in fatty acids in living cells. In addition, we were able to detect fatty acids along with other hydrophilic molecules in one sample of live cells without extraction. Overall, the high sensitivity and resolution along with the application to live cells should make the NUS HSQC approach attractive in studying carbon flux information in metabolic studies.
authors.affiliation: Natural Product Research Institute, College of Pharmacy, Seoul National University , Sillim-dong, Gwanak-gu, Seoul 151-742, Korea.
authors.forename: Sujin
authors.initials: S
authors.lastname: Lee
authors.affiliation: Natural Product Research Institute, College of Pharmacy, Seoul National University , Sillim-dong, Gwanak-gu, Seoul 151-742, Korea.|Department of Biochemistry and Molecular Biology, School of Medicine, Shenzhen University , Shenzhen 518060, China.
authors.forename: He
authors.initials: H
authors.lastname: Wen
authors.affiliation: Natural Product Research Institute, College of Pharmacy, Seoul National University , Sillim-dong, Gwanak-gu, Seoul 151-742, Korea.
authors.forename: Yong Jin
authors.initials: YJ
authors.lastname: An
authors.affiliation: Natural Product Research Institute, College of Pharmacy, Seoul National University , Sillim-dong, Gwanak-gu, Seoul 151-742, Korea.|Natural Constituents Research Center, Korea Institute of Science and Technology (KIST) , Gangneung 25451, Korea.
authors.forename: Jin Wook
authors.initials: JW
authors.lastname: Cha
authors.affiliation: National Center for Inter-University Research Facilities (NCIRF), Seoul National University , Sillim-dong, Gwanak-gu, Seoul 151-742, Korea.
authors.forename: Yoon-Joo
authors.initials: YJ
authors.lastname: Ko
authors.affiliation: Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School , Boston, Massachusetts 02115, United States.
authors.forename: Sven G
authors.initials: SG
authors.lastname: Hyberts
authors.affiliation: Natural Product Research Institute, College of Pharmacy, Seoul National University , Sillim-dong, Gwanak-gu, Seoul 151-742, Korea.
authors.forename: Sunghyouk
authors.identifier: 0000-0003-1981-3274
authors.initials: S
authors.lastname: Park
mesh_terms: D000085:Acetates / Q000032:analysis / Q000378:metabolism; D000818:Animals; D002247:Carbon Isotopes / Q000032:analysis / Q000378:metabolism*; D066241:Carbon-13 Magnetic Resonance Spectroscopy / Q000379:methods*; D045744:Cell Line, Tumor; D002470:Cell Survival; D007938:Leukemia / Q000378:metabolism; D053858:Metabolic Networks and Pathways; D055432:Metabolomics / Q000379:methods*; D051379:Mice; D013048:Specimen Handling / Q000379:methods
chemical_list: D000085:Acetates; D002247:Carbon Isotopes