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 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Andreas Pliickthun 5. High Pressure Effects on Protein Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Protein dynamics are critical to the structure and function of proteins. However, due to the complexity they inherently bring to the protein design problem, dynamics historically have not been considered in computational protein design (CPD). Herein, we present meta-MSD, a new CPD methodology for the design of protein dynamics. We applied our methodology to the design of a novel mode of conformational exchange in Streptococcal protein G domain B1, producing dynamic variants we termed DANCERs. Predictions were validated by NMR characterization of selected DANCERs, confirming that our meta-MSD framework is suitable for the computational design of protein dynamics. We then performed a thorough NMR characterization of the sequence determinants of dynamics in one DANCER, isolating two mutations responsible for the novel dynamics this protein exhibits. The first, A34F, is responsible for destabilizing the highly stable native G?1 conformation, allowing the protein to sample other conformational states. The second, V39L mediates subtle interactions that stabilize the designed conformational trajectory in the context of the A34F mutation. Together, these results highlight the role of protein plasticity in the development of dynamics and the need for highly accurate computational tools to approach similar design problems. Finally, we present an NMR-based characterization of structural dynamics in a family of related red fluorescent proteins (RFPs) and pinpoint regions of the RFP structure where dynamics correlate to RFP brightness. This overview of the RFP dynamics-function relationship will be used in future projects to perform a computation design of functional dynamics in RFPs.

This book discusses how biological molecules exert their function and regulate biological processes, with a clear focus on how conformational dynamics of proteins are critical in this respect. In the last decade, the advancements in computational biology, nuclear magnetic resonance including paramagnetic relaxation enhancement, and fluorescence-based ensemble/single-molecule techniques have shown that biological molecules (proteins, DNAs and RNAs) fluctuate under equilibrium conditions. The conformational and energetic spaces that these fluctuations explore likely contain active conformations that are critical for their function. More interestingly, these fluctuations can respond actively to external cues, which introduces layers of tight regulation on the biological processes that they dictate. A growing number of studies have suggested that conformational dynamics of proteins govern their role in regulating biological functions, examples of this regulation can be found in signal transduction, molecular recognition, apoptosis, protein / ion / other molecules translocation and gene expression. On the experimental side, the technical advances have offered deep insights into the conformational motions of a number of proteins. These studies greatly enrich our knowledge of the interplay between structure and function. On the theoretical side, novel approaches and detailed computational simulations have provided powerful tools in the study of enzyme catalysis, protein / drug design, protein / ion / other molecule translocation and protein folding/aggregation, to name but a few. This work contains detailed information, not only on the conformational motions of biological systems, but also on the potential governing forces of conformational dynamics (transient interactions, chemical and physical origins, thermodynamic properties). New developments in computational simulations will greatly enhance our understanding of how these molecules function in various biological events.

The aim this volume is to present the methods, challenges, software, and applications of this widespread and yet still evolving and maturing field. Computational Protein Design, the first book with this title, guides readers through computational protein design approaches, software and tailored solutions to specific case-study targets. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Authoritative and cutting-edge, Computational Protein Design aims to ensure successful results in the further study of this vital field.

Introduction to Proteins provides a comprehensive and state-of-the-art introduction to the structure, function, and motion of proteins for students, faculty, and researchers at all levels. The book covers proteins and enzymes across a wide range of contexts and applications, including medical disorders, drugs, toxins, chemical warfare, and animal behavior. Each chapter includes a Summary, Exercies, and References. New features in the thoroughly-updated second edition include: A brand-new chapter on enzymatic catalysis, describing enzyme biochemistry, classification, kinetics, thermodynamics, mechanisms, and applications in medicine and other industries. These are accompanied by multiple animations of biochemical reactions and mechanisms, accessible via embedded QR codes (which can be viewed by smartphones) An in-depth discussion of G-protein-coupled receptors (GPCRs) A wider-scale description of biochemical and biophysical methods for studying proteins, including fully accessible internet-based resources, such as databases and algorithms Animations of protein dynamics and conformational changes, accessible via embedded QR codes Additional features Extensive discussion of the energetics of protein folding, stability and interactions A comprehensive view of membrane proteins, with emphasis on structure-function relationship Coverage of intrinsically unstructured proteins, providing a complete, realistic view of the proteome and its underlying functions Exploration of industrial applications of protein engineering and rational drug design Each chapter includes a Summary, Exercies, and References Approximately 300 color images Downloadable solutions manual available at www.crcpress.com For more information, including all presentations, tables, animations, and exercises, as well as a complete teaching course on proteins' structure and function, please visit the author's website: http://ibis.tau.ac.il/wiki/nir_bental/index.php/Introduction_to_Proteins_Book. Praise for the first edition "This book captures, in a very accessible way, a growing body of literature on the structure, function and motion of proteins. This is a superb publication that would be very useful to undergraduates, graduate students, postdoctoral researchers, and instructors involved in structural biology or biophysics courses or in research on protein structure-function relationships." --David Sheehan, ChemBioChem, 2011 "Introduction to Proteins is an excellent, state-of-the-art choice for students, faculty, or researchers needing a monograph on protein structure. This is an immensely informative, thoroughly researched, up-to-date text, with broad coverage and remarkable depth. Introduction to Proteins would provide an excellent basis for an upper-level or graduate course on protein structure, and a valuable addition to the libraries of professionals interested in this centrally important field." --Eric Martz, Biochemistry and Molecular Biology Education, 2012

Misregulation of protein signaling pathways is the basis for many human diseases, and thus 95% of Food and Drug Administration approved drugs target proteins. Proteins are dynamic entities which can undergo transitions to reach different conformational states. The conformational state of a protein, or its three-dimensional shape, is intricately linked to functions, such as association with endogenous or exogenous binding partners, or catalysis. Thus, it is of interest to the pharmacological community to understand the mechanisms of protein conformational state transitions in order to better target and control protein functions. In two case studies, I show the importance of understanding protein dynamics in protein function and drug design. In the case of human immunodeficiency virus-1 (HIV-1) protease, a tremendous "open-and-closed" conformational transition is revealed by Molecular Dynamics Simulations (MDS). Through observing the dramatic difference in effectiveness of two Darunavir inhibitor derivatives differentiated by a single atom at locking the protease in the closed conformation, we discovered the residues and mechanism that lead to the protease's conformational transition. This mechanism also explained the significant difference in the binding conformation and binding affinity of these two inhibitors. This study provides insight on how to improve the potency and anti-viral capacity of these compounds. In the second case study, MDS enabled us to observe the conformational transitions of a family of seven isoforms known as the 14-3-3 proteins. Many vital cellular processes involve all or select 14-3-3 isoforms, making this family very difficult to target. Through MDS, I discovered different conformational samplings among these 14-3-3 isoforms which were then validated by SAXS. Subsequently, a FRET-based ligand binding assay was developed which can screen for preferential 14-3-3 isoform binding of endogenous ligands, giving hope that using conformations unique to a 14-3-3 isoform of interest can provide a method for selective drug design