Role of anisotropic interactions in protein crystallization.

We have studied a simple model colloidal fluid to assess the role of anisotropic interactions in crystallization process when the interaction potential is short ranged compared with the size of the molecule, which is the case for the effective interaction between protein molecules in aqueous solutions. Using Monte Carlo simulations we have calculated the phase diagrams of soft dumbbell systems with different anisotropic interactions. It is shown that the anisotropic interactions change the phase behavior not only quantitatively but also qualitatively. By exploiting the anisotropic interactions in the crystallization process additional avenues for the search of optimal crystallization conditions are discussed.