Indefinite isoenthalpic self-association of solute molecules

Consideration is given to the indefinite self-association of biological molecules assuming that each step-wise addition of monomer is characterized by the same enthalpy change, and that the second virial coefficients adequately describe the thermodynamic nonideality. Statistical thermodynamic models are used to calculate translational and rotational entropy changes accompanying the addition of each monomer to the aggregate. Three polymerization schemes are explored in which the solute species are modeled as right circular cylinders of various length/radius ratios. The analysis is applied to published data on the self-association of bovine liver glutamate dehydrogenase.