ADVANCES IN ANALYSIS OF MICROBIAL METABOLIC FLUXES VIA C-13 ISOTOPIC LABELING

Metabolic flux analysis via C-13 labeling (C-13 MFA) quantitatively tracks metabolic pathway activity and determines overall enzymatic function in cells. Three core techniques are necessary for C-13 MFA: (1) a steady state cell culture in a defined medium with labeled-carbon substrates; (2) precise measurements of the labeling pattern of targeted metabolites; and (3) evaluation of the data sets obtained from mass spectrometry measurements with a computer model. to calculate the metabolic fluxes. In this review, we summarize recent advances in the C-13-flux analysis technologies, including mini-bioreactor usage for tracer experiments. isotopomer analysis of metabolites via high resolution mass spectrometry (such as GC-MS, LC-MS, or FT-ICR), high performance and large-scale isotopomer modeling programs for flux analysis, and the integration of fluxomics with other functional genomics studies. It will be shown that there is a significant value for 13 C-based metabolic flux analysis in many biological research fields. (C) 2008 Wiley Periodicals, Inc., Mass Spec Rev 28:362-375, 2009