Growing lysozyme crystals under various physicochemical conditions: Computer modelling

A computer model of the growth of lysozyme crystals under a variety of physicochemical conditions is proposed. The growth unit was composed of the protein in its HP (hydrophobic–hydrophilic) coarsegrained cubic representation. The growth of the crystal was driven by hydrophobic structural interactions between incoming growth units and the surface of the crystal. The energies of HH, HP and PP interactions were taken from the well-known HP model and modified within the limits of the Miyazawa–Jernigan matrix describing interactions between amino acids in proteins. Suitably chosen energy values of HH, HP and PP interactions can mimic various physicochemical conditions of the system in which the crystal can grow. Some combinations of energy values have produced different crystal forms: a physical fact confirmed by experiment.