Multiple Energy Varieties

The list of energy varieties in Table 2.1 is not exhaustive for several reasons. A first reason is the existence of homothetic varieties, that is, varieties in which the container is a multiple of another one. This can be merely a question of the unit used for quantifying the container. An example is the corpuscular energy and the physical chemical energy that are related by the Avogadro constant. 

This system is tackled again in Chapter 13 in case study K5 Rotating Bodies as an example of multiple couplings between energy varieties. 

Energetic coefficients Connections Energy coupling Multiplicity (stoichiometry) A (scalar, vector) V (scalar, vector) Association of energy varieties Association of Formal Objects... 

A state variable converted into the state variable in the same family but belonging to another energy variety, by multiplication by a coupling factor. 

A translated variable results from the multiplication of a state variable by a coupling factor, thus producing a variable in another energy variety. It amounts to expressing the state variable in the units of the other energy variety (e.g., a translated electrical potential into physical chemical energy, by multiplication with the Faraday constant, has the Joule per mole as a unit) (cf. Chapter 12). 

So far, as in Equation (3.33), the hydrolyses of ATP and other high-energy phosphates have been portrayed as simple processes. The situation in a real biological system is far more complex, owing to the operation of several ionic equilibria. First, ATP, ADP, and the other species in Table 3.3 can exist in several different ionization states that must be accounted for in any quantitative analysis. Second, phosphate compounds bind a variety of divalent and monovalent cations with substantial affinity, and the various metal complexes must also be considered in such analyses. Consideration of these special cases makes the quantitative analysis far more realistic. The importance of these multiple equilibria in group transfer reactions is illustrated for the hydrolysis of ATP, but the principles and methods presented are general and can be applied to any similar hydrolysis reaction. 

MM methods, originally developed for organic compounds, have been modified to describe metal complexes [13-17] where polarization interactions must be considered and where a variety of geometrical configuration is observed. This structural diversity reflecting the existence of multiple local energy minima is due to ligand-dependent effects observed in complexes of... 

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