Biophysical Society Thematic Meeting

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

, Johan Van Weyenbergh

, Rolf Fendel

, Theo Thepen

Stefan Barth

Forschungszentrum Juelich, Juelich, NRW, Germany,

Oswaldo Cruz Foundation (FIOCRUZ),

Salvador, Bahia, Brazil,

Fraunhofer IME, Aachen, NRW, Germany,

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.