Mammalian central energy metabolism.

<p>Glucose metabolism, including the pentose phosphate pathway, glycolysis, and the TCA cycle, was modeled as a network using a stoichiometric matrix. Each colored square represents a biochemical reaction, and each line represents a metabolite. Reversible reactions shown in blue, and irreversible reactions shown in red. Arrows indicate the direction of irreversible reactions. Anaplerotic reactions that replenish TCA reactants are represented by hashed squares. The curved arrow indicates the direction of normal flux in the TCA cycle. Selected metabolites (<i>i</i>.<i>e</i>.glucose, lactate, and glutamine) shown explicitly.