Legendre transforms composition calculations

Since concentrations of ATP, ADP, NADox, and NADred may be in steady states, it is of interest to calculate equilibrium compositions that correspond with these steady state concentrations. These calculations are referred to as level 3 equilibrium calculations because they are based on the introduction of [ATP], [ADP], and the like, as natural variables by use of a Legendre transform. 

The equilibrium composition for an enzyme-catalyzed reaction or a series of enzyme-catalyzed reactions can be calculated by using equcalcc or equcalccrx. The first of these programs requires a conservation matrix. The second requires a stoichiometric matrix. The second program is recommended, especially when water is involved as a reactant, because the convention that when dilute aqueous solutions are considered, the activity of water is taken to be unity, means that a second Legendre transform is necessary. 

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