Dataset Information

Fragmentation of Dicarboxylic and Tricarboxylic Acids in the Krebs Cycle Using GC-EI-MS and GC-EI-MS/MS.

ABSTRACT: Isotope labeling measurements using mass spectrometry can provide informative insights on the metabolic systems of various organisms. The detailed identification of carbon positions included in the fragment ions of dicarboxylic and tricarboxylic acids in central carbon metabolism is needed for precise interpretation of the metabolic states. In this study, fragment ions containing the carbon backbone cleavage of dicarboxylic and tricarboxylic in the Krebs cycle were investigated by using gas chromatography (GC)-electron ionization (EI)-MS and GC-EI-MS/MS. The positions of decarboxylation in the dicarboxylic and tricarboxylic acids were successfully identified by analyses using position-specific 13C-labeled standards prepared by in vitro enzymatic reactions. For example, carboxyl groups of C1 and C6 of trimethylsilyl (TMS)- and tert-butyldimethylsilyl (TBDMS)-derivatized malic and citric acids were primarily cleaved by EI. MS/MS analyses were also performed, and fragment ions of TBDMS-citric and ?-ketoglutaric acids (?KG) with the loss of two carboxyl groups in collision-induced dissociation (CID) were observed.

SUBMITTER: Okahashi N

PROVIDER: S-EPMC6920549 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Fragmentation of Dicarboxylic and Tricarboxylic Acids in the Krebs Cycle Using GC-EI-MS and GC-EI-MS/MS.

Okahashi Nobuyuki N Kawana Shuichi S Iida Junko J Shimizu Hiroshi H Matsuda Fumio F

Mass spectrometry (Tokyo, Japan) 20190830 1

Isotope labeling measurements using mass spectrometry can provide informative insights on the metabolic systems of various organisms. The detailed identification of carbon positions included in the fragment ions of dicarboxylic and tricarboxylic acids in central carbon metabolism is needed for precise interpretation of the metabolic states. In this study, fragment ions containing the carbon backbone cleavage of dicarboxylic and tricarboxylic in the Krebs cycle were investigated by using gas chro ...[more]

PMID: 32010541

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Dataset Information

Fragmentation of Dicarboxylic and Tricarboxylic Acids in the Krebs Cycle Using GC-EI-MS and GC-EI-MS/MS.

Publications

Fragmentation of Dicarboxylic and Tricarboxylic Acids in the Krebs Cycle Using GC-EI-MS and GC-EI-MS/MS.

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