Expression systems are in widespread use for cloning specific genes, for synthesizing the encoded proteins for structural and functional analysis, and for large-scale preparation of current use with background information and advice on the merits of each, step-by-step practical protocols, troubleshooting, and details of the latest applications. These two books, the first of four volumes are thoroughly revised and up-dated versions of the original ones published in the Practical Approach series. Together they will offer a complete guide to the major techniques required by modern molecular biology laboratories.