Understanding protein crystallization: the role of biomolecular solvation

Department of Mechanical Engineering & Materials Science Seminar

"Understanding protein crystallization: the role of biomolecular solvation"

Irem Altan
PhD. Candidate
Duke University, Durham, NC

Proteins self-assemble into a wide variety of structures such as virus capsids, amyloid fibers, and protein crystals. The latter typically requires extreme chemical conditions and substantial trial and error, as proteins have evolved to be recalcitrant to crystallization. Because diffraction methods are still the most common tool for obtaining protein structures, however, understanding the physicochemical processes that underlie protein crystallization is critical. Using both all-atom and coarse-grained simulations and soft matter theory, we studied the effect of biomolecular solvation in (i) extracting structural information from protein X-ray diffraction data and (ii) the inverted solubility of a γD-crystallin mutant. For (i), we find that classical MD water models fall short of recapitulating experimental water density within a protein crystal, but do capture information complementary to that contained in diffraction data. For (ii), while we find that the hydrophobic effect could thermodynamically be responsible for inverted solubility, microscopic evidence for protein surface hydrophobicity remains elusive.

Friday, October 18, 2019
3:00-4:00 pm
Location – Mason 107
Host: Professor Corey O'Hern