Preface

P roteins are like people: they are highly diverse, with very few traits shared by the entire population. Even close relatives often have very different structural (physical) characteristics and behave quite differently. This heterogeneity presents challenges for scientists interested in studying protein structure and function. The need for a readily accessible, updatable reference for protein methods has grown in tandem with the ongoing protein science renaissance driven by advances in molecular biology, genetics, structural biology, and related disciplines. Using recombinant methods, it is now practical to overexpress both normal and reengineered forms of a protein and to create chimeric proteins with unique new properties. The ability to express proteins usually found in low abundance at high levels and to manipulate their amino acid sequences provides unprecedented opportunities to study a vast array of proteins and their associated biological processes (both in vitro and in vivo). The combination of biochemical, biophysical, and high-resolution structural analyses of proteins with manipulation of the associated genes (in cultured cells or an entire mammalian organism) has already led to spectacular advances in many areas of biotechnology and molecular medicine.