The Use of a Magnetic Field and Magnetic Force as a Means to Improve the Quality of Protein Crystals - Molecules: Nucleation, Aggregation and Crystallization - page 203

Applied Physics), and his supervisor Prof. Koji Okano thought of apply-
ing a static magnetic field during protein crystal growth. They asked the
present author how to grow protein crystals and learned about the condi-
tions for growing hen egg-white lysozyme crystals, a protein biosynthe-
sized by chickens. The protein's function is to catalyze the hydrolysis of
polysaccharides comprising the cell walls of a number of bacteria. The
egg-white contains a considerable amount of lysozyme; when bacteria
invade the egg, the lysozyme can kill them by attacking the outer cell wall
and protect the yolk. The crystallization conditions taught to Kuroda were
basically the same as reported by Alderton et al . (1945): 30-50 mg/ml
protein, 3-5% (w/w) NaCl as a crystallizing agent, bringing the pH to
about 4.5, and keeping the temperature of the batch at around 15 C.

Tetragonal crystals grow under these conditions. An electromagnet was

°

Fig. 1. A photomicrograph of hen egg-white lysozyme crystals grown without a mag-
netic field. A control to be compared with Fig. 2.