Quantification of microbial phenotypes using 13C-Fluxomics

Abstract

Systems biology is an emerging tool in microbiology that helps us to understand cellular processes and to optimise microbes for production purposes1. It strongly relies on the use of large datasets created using omics tools followed by data mining and modelling in order to gain new insights into biology. The creation of the datasets is usually comprised of genomics defining the overall capacity of a microbe, transcriptomics and proteomics as a measure of the active set of reactions within the overall capacity and more recently metabolomics as a measure of the available building blocks and (if performed quantitatively) of the thermodynamic driving forces governing the intracellular reactions. The latter can define feasibility of pathways as well as reaction reversibility, which can be important constraints for the analysis of metabolic networks. However, all these omics techniques fail to quantitatively assess the metabolic phenotype in its ultimate form: The reaction rates, or metabolic fluxes inside the cell that define the material transfer rates from one metabolite pool to another and from pathway to pathway. The ‘omics technology that enables the quantification of fluxes is metabolic flux analysis, or fluxomics.