Using neutron backscattering spectroscopy and complementary NSE, SAXS, and DLS experiments, we have very systematically explored the model protein Bovine Serum Albumin (BSA) in aqueous solutions. From these studies, we have derived the necessary experimental and analytical frameworks to obtain the translational diffusion of the dissolved proteins [F.Roosen-Runge et al., PNAS 108, 11815 (2011); M.Hennig et al., Soft Matter 8, 1628 (2012); M. Heinen et al., Soft Matter 8, 1404 (2012)]. We have also developed models for the influence of charge screening on the diffusion in BSA protein solutions [M. Hennig, PhD thesis, University of Tuebingen 2011]. These models point towards possible transient or dynamic clusters at suitable trivalent salt concentrations in the protein solutions. However, to fully develop and test our models, we have to carry out a comparative study on a different protein model system. We therefore propose to extend our study of the dependence of the diffusion on the ionic strength of the solutions to the new protein Ovalbumin (OVA). OVA differs in shape, size, and charge pattern from BSA. These differences can be expected to influence cluster formation.