Summary
Uses isotope tracers and models to measure reaction rates through metabolic networks.
In depth
Labelled substrates (13C-glucose) are traced by mass spectrometry or NMR. Flux balance analysis predicts distribution using stoichiometry and constraints.
Flux is the rate of flow through a pathway, not concentration. Steady-state labelling reveals pathway activity.
Example: 13C tracing shows how tumour cells use glucose and glutamine.
Metabolic flux is the rate at which material flows through a pathway, which cannot be seen from concentrations of metabolites alone. In 13C flux analysis, cells are fed glucose labelled with carbon-13, and mass spectrometry or NMR measures how the label appears in downstream molecules.
A mathematical model of the network then fits the labelling patterns to calculate fluxes through glycolysis, the pentose phosphate pathway and the Krebs cycle. Flux balance analysis, a related method, uses stoichiometry and constraints to predict fluxes at the genome scale. It is used to design metabolic engineering strategies and to study cancer and diabetes.
Example: showing that cancer cells use glutamine to feed the Krebs cycle.
Key idea: flux is the real activity of a network.
Frequently asked questions
What is Metabolic Flux Analysis?
Uses isotope tracers and models to measure reaction rates through metabolic networks.
Which area of biology covers Metabolic Flux Analysis, and how advanced is it?
Metabolic Flux Analysis is one of the 53 topics in Metabolism & Bioenergetics. It is rated Advanced, so it suits learners who want specialist depth. Related topics in this area include Systems Biology of Metabolism, Metabolomics, Metabolic Engineering.
Can you give an example of Metabolic Flux Analysis?
It identified how cancer cells use glutamine.
What should I learn before Metabolic Flux Analysis?
Work through the Beginner topics in Metabolism & Bioenergetics first, such as Metabolism, Anabolism and Catabolism, ATP, then return to Metabolic Flux Analysis. Advanced topics assume the Intermediate vocabulary.
What topics are related to Metabolic Flux Analysis?
The closest topics to Metabolic Flux Analysis are Systems Biology of Metabolism, Metabolomics, Metabolic Engineering, Cellular Respiration. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Metabolic Flux Analysis?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Metabolic Flux Analysis. To practise the whole of Metabolism & Bioenergetics, use the Metabolism & Bioenergetics quiz.
How is Metabolic Flux Analysis different from Systems Biology of Metabolism?
Metabolic Flux Analysis: Uses isotope tracers and models to measure reaction rates through metabolic networks. Systems Biology of Metabolism: Genome-scale models predict growth and pathway usage under constraints. Read both side by side and note what each one explains.
How should I study Metabolic Flux Analysis step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Systems Biology of Metabolism and explain the difference aloud. Finally, take the Metabolism & Bioenergetics quiz and come back to this page for any question you miss.