Dresden 2017 – wissenschaftliches Programm
CPP 18.6: Poster
Montag, 20. März 2017, 18:30–21:00, P1C
Binding probability model for protein cluster formation in aqueous solution — •Michal K. Braun1, Marco Grimaldo2, Felix Roosen-Runge2, Tilo Seydel2, Fajun Zhang1, and Frank Schreiber1 — 1Institut für Angewandte Physik, Universität Tübingen, 72076 Tübingen — 2ILL, Grenoble, France
Due to the specific nature of the interactions, in certain cases protein crystallization can be described by a model of globular particles with attractive patches . Clusters of proteins are possible precursors for crystals. We have investigated self-diffusion  and collective diffusion  of clusters of the model protein bovine serum albumin (BSA) that form in the presence of a trivalent salt (YCl3). The self- and collective diffusion coefficients are obtained from neutron and dynamic light scattering (DLS) data, respectively. We present new DLS data on BSA in the presence of another trivalent salt, namely LaCl3. Our data can be analyzed based on simple Brownian diffusion . The total scattering function S(q, ω) is linked to the model of patchy particles. In this way, the dependence of the binding probability pb on the salt concentration is obtained. The measured self- and collective diffusion coefficients fall onto separate master curves [2,3], which only depend on the ratio of salt and protein. In the case of self-diffusion a master curve was also found for pb. From the new collective diffusion data pb will be extrated analogously and will be compared to pb from the self-diffusion data.
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Grimaldo et al., JPCL, 6, 2577, 2015
Soraruf et al., Soft Matter, 10, 894, 2014