Application of metabolic control analysis to the pathways of carbohydrate breakdown in Hymenolepis diminuta.

The application of metabolic control theory to carbohydrate breakdown in the tapeworm Hymenolepis diminuta shows that it is not necessary for both phosphoenolpyruvate carboxykinase and pyruvate kinase to be modulated in order to control the relative fluxes through the two arms of the phosphoenolpyruvate branchpoint. Changes in activity of enzymes outside of the two branches also influence the flux ratio. Control coefficients of individual enzymes for the fluxes through phosphoenolpyruvate carboxykinase and pyruvate kinase are not fixed, but vary as the flux ratio between the two arms of the branchpoint changes. The metabolic model can also be used to evaluate the role of the fructose-1,6-bisphosphate loop and to calculate metabolite transition time control coefficients.