AGha hydrophobic association

Equation (5.9) provides an initial insight into the relationship between moving the T,-divide and changes in free energy of hydrophobic association it is of use when the value of AS,(x), or AH,(x) from which it is derived, is not available. Nonetheless, the limitations of Equation (5.9) become apparent when both AS,(x) and AS,(ref) are known, because reversal of roles of the reference and altered state should simply reverse the sign of AGha(X)> and this is not the case due to the approximation of Equations (5.3) and (5.4). 

Energy Resources of the Consilient Mechanism Changing the Free Energy (AGha) for Hydrophobic Association... 

Different Estimates of Transition Temperature Used in Calculating the Gibbs Free Energy for Hydrophobic Association, AGha, by Equation (5.10a)... 

Figure 5.10. An embodiment of the comprehensive hydrophobic effect in terms of a plot of the temperature for the onset of phase separation for hydrophobic association, Tb, versus AGha. the Gibbs free energy of hydrophobic association for the amino acid residues, calculated by means of Equation (5.10b) using the heats of the phase (inverse temperature) transition (AH,). Values were taken from Table 5.3. Tb and T, were determined from the onset of the phase separation as defined in Figure 5.1C,B, respectively. The estimates of AGha utilized the AH, data listed in Table 5.1 for fx = 0.2 but extrapolated to fx = 1, and the Gly (G) residue was taken as the...

Table 5.3. Hydrophobicity Scale in terms of AGha, the change in Gibbs free energy for hydrophobic association, for amino acid residue (X) of chemically synthesized poly[fv(GVGVP), fx(GXGVP)], 40m ml, mw = 100 kDa in 0.15 N NaCl, 0.01 M phosphate, using the net heat of the inverse temperature transition, AGha = [AH,(GGGVP) - AH.(GXGVP)] for the fx = 0.2 data extrapolated to f = 1.

Table 5.4. AGha(x) for hydrophobic association of a given composition of model protein per mole for the steepest slope of AT, per change in salt concentration.

Coupling of Functional Groups by Means of the Consilient Mechanism and by Means of Their Common Dependence on the Gibbs Free Energy of Hydrophobic Association, AGha... 

Protein-based molecular machines of the first kind directly use the change in free energy of hydrophobic association, AGha, as a contraction for the performance of mechanical work. 

Figure 5.33. Representation of lowering the onset temperature, Tt(b), of the inverse temperature (phase) transition for hydrophobic association from the dissociated state at 37°C to 25°C, that is, to a temperature just sufficient to achieve essentially complete hydrophobic association. Hydrophobic association results from the summation of all of the variables (-(- and -) that contribute to AGha, i.e.. 2iAG HA. This summation represents the AG a additivity principle.

The change in Gibbs free energy for hydrophobic association, AGha, affects and is affected by the forms of energy utilized by living organ-... 

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