This volume is a collection of articles from the proceedings of the International School of Structural Biology and Magnetic Resonance 3rd Course: Protein Dynamics, Function, and Design. This NATO Advance Study Institute was held in Erice at the Ettore Majorana Centre for Scientific Culture on April 16-28, 1997. The aim of the Institute was to bring together experts applyipg different physical methods to problems of macro molecular dynamics-notably x-ray diffraction, NMR and other forms of spectroscopy, and molecular dynamics simulations. Emphasis was placed on those systems and types of problems-such as mechanisms of allosteric control, signal transmission, induced fit to different ligands with its implications for drug design, and the effects of dynamics on structure determination-where a correlation of findings obtained by different methods could shed the most light on the mechanisms involved and stimulate the search for new approaches. The individual articles represent the state of the art in each of the areas cov ered and provide a guide to the original literature in this rapidly developing field. v CONTENTS 1. Determining Structures of ProteinlDN A Complexes by NMR Angela M. Gronenbom and G. Marius Clore 2. Fitting Protein Structures to Experimental Data: Lessons from before Your Mother Was Born . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Jeffrey C. Hoch, Alan S. Stem, and Peter J. Connolly 3. Multisubunit Allosteric Proteins. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 William N. Lipscomb 4. Studying Protein Structure and Function by Directed Evolution: Examples with Engineered Antibodies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37Andreas Pliickthun 5. High Pressure Effects on Protein Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . .