This connection is provided by usage of common cofactors such as ATP, ADP, NADH and NADPH.
Existing metabolic networks control the movement of molecules through their enzymatic steps by regulating enzymes that catalyze irreversible reactions.
The movement of molecules through reversible steps is generally unregulated by enzymes, but rather regulated by the concentration of products and reactants.
A result that may seem at first counter intuitive, is that regulated steps tends to have small flux control coefficients.
Growing cells require synthesis of new nucleotides, membranes and protein components.
The enhanced flux observed in abnormally growing cells is brought about by high glucose uptake.
[6] Through studying these changes, it is possible to better understand the mechanisms of cell growth and where possible develop treatments to counter the effects of enhanced metabolism.
[5] This assumption means that for a given metabolic network the balances around each metabolite impose a number of constraints on the system.
In order to avoid the complexity of data analysis, a simpler method of estimating flux ratios has recently been developed which is based on cofeeding unlabelled and uniformly 13C labelled glucose.