Total free energy of binding

When cooperativity is ignored, contributions of AG valnes to the total free energies of binding may be added together. Approaches based on functional group additives equation (21.7) or the additivity of free enthalpy components equation (21.8) have freqnently been applied to understand and predict protein-ligand interactions. Pioneering studies in this held were performed by Andrews et al. and Lau and Pettitt. ... 

Eq. 1 log Vmax, rate constant for CYP2E mediated metabolism AE,. E umo - EHomo-Eq. 2 AGbind, free energy of binding HB, total number of hydrogen bond acceptors and donors Mr, relative molecular mass Nm, number of active site hydrogen bonds formed between substrate and human CYP2E1. 

Total Available Binding Sites Average Binding Constant Free Energy of Binding... 

Enzyme inhibition data is most conveniently expressed as -log Ki or pKi. In this form, the binding values are directly proportional to the free energy of binding and, therefore, can be dissected into smaller, additive components. For example, as a first approximation, the total pKi of an inhibitor can be divided evenly among its lattice points. These lattice points are presumed to account for the binding of every part of the molecule. Such an equal distribution of partial pKi values is clearly simplistic, since it is likely that a molecule contains portions (typically functional groups) that bind more strongly than other portions. 

Figure 20 The relationship between amplification and free energy of binding for all of the hosts in two randomly generated DCLs that differ only in the way the binding constants are distributed over the various hosts. In both DCLs, the total concentration of the building blocks and the concentration of the template is 10 mM. values for the correlation between free energy and the logarithm of the amplification factor (taking only significantly amplified hosts into account) are 0.72 and 0.24, respectively. (Reproduced from Ref. 74. Wiley-VCH, 2004.)...

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