MICRO DIFFUSION CELLS FOR GROWTH OF SINGLE PROTEIN CRYSTALS BY MEANS OF EQUILIBRIUM DIALYSIS

Microdiffusion cells are described for crystallization of small volumes of protein solutions by equilibrium dialysis against a precipitant. The cells which may contain down to 10 microliters of protein solution are made either from capillaries of glass or transparent polymer sealed with cellophane membranes or from X-ray capillaries sealed with semipermeable diaphragms of polyacrylamide. The use of these microdiffusion cells has been explored both for growing large protein crystals and for chemical treatment of one or a few single crystals in their mother liquor. The methods have been applied to lysozyme, an extracellular proteinase from a strain of Arthrobacter and to rabbit muscle aldolase. The factors influencing the growth of protein crystals are discussed and other methods for protein crystallization are briefly reviewed. © 1968.