Comprehensive isotopomer analysis of glutamate and aspartate in small tissue samples.

ABSTRACT: Stable isotopes are powerful tools to assess metabolism. ¹³C labeling is detected using nuclear magnetic resonance (NMR) spectroscopy or mass spectrometry (MS). MS has excellent sensitivity but generally cannot discriminate among different ¹³C positions (isotopomers), whereas NMR is less sensitive but reports some isotopomers. Here, we develop an MS method that reports all 16 aspartate and 32 glutamate isotopomers while requiring less than 1% of the sample used for NMR. This method discriminates between pathways that result in the same number of ¹³C labels in aspartate and glutamate, providing enhanced specificity over conventional MS. We demonstrate regional metabolic heterogeneity within human tumors, document the impact of fumarate hydratase (FH) deficie

SUBMITTER: Cai F 

PROVIDER: S-EPMC10732579 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature