报告人：Dr.Fajun Zhang
Institut für Angewandte Physik, Universität Tübingen, Germany
题目：Tuning Interactions in Protein Solutions towards Controlled Protein Crystallization
时间：09:30 am, Sep. 17th （Thursday）
地点：Conference Room B, BLDG 909-1F
摘要：
Non-specific protein-protein interactions in aqueous solution play a crucial role on protein crystallization and protein-aggregation related diseases, such as cataracts, and sickle cell anemia [1]. A comprehensive understanding of interactions in protein solutions is still a challenge. In this talk, I will first show an efficient way to tune interactions and phase behavior in protein solutions using salts, in particular with trivalent salts. For example, negatively charged globular proteins at neutral pH in the presence of multivalent metal ions undergo a “reentrant condensation (RC)” phase behavior [2,3]. Small angle X-ray and neutron scattering (SAXS/SANS) have been used to characterize the effective interactions under various conditions. In the second part, I will discuss the nonclassical mechanisms of protein crystallization based on our recent work. We show that crystallization near phase boundaries follows different mechanisms [4,5]. Real-time SAXS studies provide the direct evidence for a two-step nucleation process, the role and the structural signature of the metastable intermediate phases in the nonclassical process of protein crystallization [5].
[1] Gunton, J. D.; Shiryayev, A.; Pagan, D. L. Protein Condensation-kinetic pathways to crystallization and disease; Cambridge University Press: New York, 2007.
[2] Zhang, F. et al. Phys. Rev. Lett. 2008, 101, 148101 and Proteins 2010, 78, 3450-3457.
[3] Roosen-Runge, F. et al. J. Phys. Chem. B 2013, 117, 5777. Sci. Rep. 2014, 4, 7016
[4] Zhang, F. et al. J. Appl. Cryst. 2011, 44, 755; Soft Matter 2012, 8, 1313 and Faraday Discuss. 2012, 159, 313.
[5] Sauter, A. et al. J. Am. Chem. Soc. 2015, 137, 1485 and Faraday Discuss. 2015, 179, 41.
简介：
http://www.physik.uni-tuebingen.de/institute/institut-fuer-angewandte-physik/forschung/physik-der-molekularen-und-biologischen-materie/biophysics-and-nanoscience.html
联系人： Prof. Steffen Duhm