Structure of peptide solutions: A light scattering and numerical study
School of Physics, The University of Edinburgh, EH9 3JZ, Edinburgh, UK
2 Physics Department, University of Fribourg, 1700, Perolles, Fribourg, Switzerland
3 Department of Applied BioSciences, ETH Zürich, 8057, Zürich, Switzerland
* e-mail: S.U.Egelhaaf@ed.ac.uk
We investigated the interactions between protein molecules in solution, in particular for low salt concentrations and thus strong electrostatic interactions where a treatment based on the second virial coefficient is not sufficient. Static and dynamic light scattering experiments on solutions containing the peptide human calcitonin (hCT) were combined with calculations based on the Ornstein-Zernike equation with the hypernetted chain (HNC) closure and computer simulations within the primitive electrolyte model. The simulation illustrates the distribution of proteins in solution and the formation of (transient) protein aggregates. It furthermore allows us to predict the physical stability of hCT solutions in dependence of ionic strength, pH and hCT concentration.
© EDP Sciences, Società Italiana di Fisica, and Springer-Verlag, 2004