Dependence of protein crystal stability on residue charge states and ion content of crystal solvent.

摘要: Protein crystallization is frequently induced by the addition of various precipitants, which directly affect protein solubility. In to organic cosolvents and long-chain polymers, salts belong most widely used precipitants in crystallography. However, despite such widespread usage, their mode action at atomistic level still largely unknown. Here, we perform extensive molecular dynamics simulations villin headpiece crystal unit cell examine its stability different concentrations sodium sulfate. We show that inclusion ions solvent high concentration can prevent large rearrangements asymmetric units a loss symmetry without significantly affecting dynamics. Of importance, similar result be achieved neutralizing several specific charged residues suggesting they may play an active role destabilization due unfavorable electrostatic interactions. Our results provide microscopic picture behind salt-induced stabilization further suggest adequate modeling realistic conditions necessary for successful crystals.