Nucleation and growth of lysozyme crystals under external electric field

Preferred orientation along c-axis of hen-egg-white lysozyme (HEWL) crystals has been observed in an external electric field. This fact was explained on the basis of a working hypothesis for specific spatial distribution of the positive electric charges on the individual HEWL molecules, and thus attributed to the (preferred) orientation of individual HEWL molecules in the solution, under these conditions. Besides, the HEWL crystals grew predominantly on the cathode side of the glass cell. Due to the electric field the crystals grew faster. These observations have been explained on the basis of recently reported measurements of Aubry and co-workers, which show an increased HEWL concentration in the solution near the cathode, and lower one near the anode. (C) 2002 Elsevier Science B.V. All rights reserved.