CRYSTALLIZING PROTEINS - A RATIONAL APPROACH

The advances in recombinant DNA technology in recent years have had a dramatic effect on the area of protein crystallization. Large amounts of pure protem produced in various expression systems have made it pos sible to conduct experiments that would have been impossible with mate rial from natural sources. With many more laboratories becoming involv ed in crystallizing proteins a great deal of new information has been generated on techniques to eliminate the so called 'bottleneck of crys tallization' in determining a three-dimensional protein structure. Mor e and more new and interesting proteins are being submitted to this la boratory for crystallization. Certain criteria may be set before cryst allization trials are started, such as solubility, purity and aggregat ion tendencies. The introduction of robots now facilitates the screeni ng of crystallization conditions. In cases where no crystals have been obtained after initial screening it can now be decided which possible modifications can be made to the protein itself to improve the chance s of obtaining crystals.