Question

Give an equation or series of equations that can be used to determine the buried nonpolar surface area resulting from the formation of a macromolecular complex.

Your equation(s) should heat capacity change due to the hydrophobic effect.

Answer 1

The entropy changes from the hydrophobic effect S_HE is well correlated with changes in nonpolar surface area, and can be determined empirically from C_p (after correction for other effects).

The equation is given as:

S_HE = 1.35* C_p*ln(T_S / 386)                                                   (1)

The bulk thermodynamics of the interactions are more completely described with a measurement of the heat capacity change of binding (C_p), which defines the temperature dependence of H and S:

        H(T) = Cp(T?T_H)                                                   (2)

        S(T) = Cp*ln(T / T_S)                                               (3)

where T_H and T_S are the temperatures at which the net binding H and S are zero, respectively.