Biophysical Society Thematic Meeting - November 16-20, 2015

Biophysics in the Understanding, Diagnosis, and Treatment of Infectious Diseases Speaker Abstracts

Use of Supercomputational Simulation of Dynamic Protein Interaction to Generate Knowledge-Driven Targeted Fusion Proteins for Treatment of Infectious Diseases Paolo Carloni 1 , Johan Van Weyenbergh 2 , Rolf Fendel 3 , Theo Thepen 3 , Stefan Barth 4 . 1 Forschungszentrum Juelich, Juelich, NRW, Germany, 2 Oswaldo Cruz Foundation (FIOCRUZ), Salvador, Bahia, Brazil, 3 Fraunhofer IME, Aachen, NRW, Germany, 4 University of Cape Town, Cape Town, Western Cape, South Africa. Human granzyme B (hGB) is a serine protease involved in immune-mediated apoptosis. Its cytotoxicity makes it potentially applicable in for novel targeted therapies. However, the effectiveness of hGB can be hampered by the cytosolic expression of a natural protein inhibitor, human Serpin B9 (hSB9). Thus, we used computational approaches to identify hGB mutations that can affect its binding to hSB9 without significantly decreasing its catalytic efficiency. Alanine-scanning calculations allowed us to identify residues of hGB important for the interaction with hSB9. Some variants were selected, and molecular dynamic simulations on the mutated hGB in complex with hSB9 in aqueous solution were carried out to investigate the effect of these variants on the stability of the complex. The point mutation R201K demonstrated strongly reduced sensitivity towards hSB9. By fusing this rationally designed human enzyme to disease-specific antibodies, we generated recombinant therapeutics e.g. targeting CD64 for treatment of Leishmaniasis and MSP4 for Malaria treatment. Further details on the activity of corresponding fusion proteins will be presented.

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