Overview

This book deals with the condensation of proteins from solution, including protein crystal nucleation and certain diseases related to undesirable protein condensation. We use the word condensation to describe a variety of possible states of matter, including dense, protein-rich fluids, amorphous aggregates, polymer fibers, gels, and crystals. Much of the book deals with understanding how to grow high quality protein crystals from aqueous solutions of protein molecules. This is of importance in structural biology, which deals with the study of the architecture and shape of biological macromolecules, and in particular with proteins and nucleic acids. Biologists are interested in knowing the structure of proteins, since structure determines function. To determine structure requires high quality protein crystals for use in X-ray crystallography. It is quite difficult to grow high quality protein crystals from solution, however; crystal nucleation is the major bottleneck in protein crystallography. Understanding the dependence of crystal nucleation on the initial conditions of the protein solution is a fundamental problem in statistical physics and is a major theme of this book. Understanding protein crystal nucleation is also important in biomedical research. For example, the sustained release of medications, such as insulin and interferon-α, depends on the slow dissolution rate of protein crystals [1–6].