Chapter 1 Introduction to the Crystallization of Biological Macromolecules

Publisher Summary Crystallization has emerged as the rate-limiting step in macromolecular crystallography and has become a major barrier to advances in structural biology. Biological macromolecules—which include proteins, nucleic acids, and their complexes—can be crystallized by a wide variety of techniques involving a broad range of reagents. The objective in all cases is to produce supersaturated mother liquors. The crystallization trials may in turn be carried out under different physical conditions, such as temperature. The chapter summarizes the most commonly employed approaches for discovering successful crystallization conditions for specific macromolecules and the factors that influence them. In addition, the chapter describes and discusses some of the classical ideas from crystallization science and protein science—such as solubility in salts as a function of pH—in terms of their practical application and addresses many of the difficulties that are commonly encountered. While the methodologies have been developed principally for protein crystallization, they are equally applicable to large biological assemblies, such as viruses and ribosomal particles.