THE KINETICS OF MULTIPLE ENZYME INHIBITION.

The adaptive fermentation of galactose by yeast is inhibited by fluoride and azide. At sufficiently low concentrations, however, it is stimulated. From a mathematical analysis, using the known fact that fluoride inhibits the enzymes enolase and adenosinetriphosphatase, it is possible to infer the existence of such stimulation. Conditions for this effect are derived which relate the sensitivities of the enzymes to the poison with the rate constants of the various reactions in the fermentation chain.