This is the first high-quality, comprehensive overview of the field of evolutionary protein design. Topics include new protein design strategies, the structures of laboratory-evolved proteins, the evolution of non-natural enzyme functions, and the theory of laboratory evolution.

This new volume of Methods in Enzymology continues the legacy of this premier serial by containing quality chapters authored by leaders in the field. This volume covers methods in protein design and it has chapters on such topics as protein switch engineering by domain insertion, evolution based design of proteins, and computationally designed proteins. - Continues the legacy of this premier serial with quality chapters authored by leaders in the field - Covers methods in protein design - Contains chapters with such topics as protein switch engineering by domain insertion, evolution-based design of proteins, and computationally designed proteins

Protein engineering is a fascinating mixture of molecular biology, protein structure analysis, computation, and biochemistry, with the goal of developing useful or valuable proteins. Protein Engineering Protocols will consider the two general, but not mutually exclusive, strategies for protein engineering. The first is known as rational design, in which the scientist uses detailed knowledge of the structure and function of the protein to make desired changes. The s- ond strategy is known as directed evolution. In this case, random mutagenesis is applied to a protein, and selection or screening is used to pick out variants that have the desired qualities. By several rounds of mutation and selection, this method mimics natural evolution. An additional technique known as DNA shuffling mixes and matches pieces of successful variants to produce better results. This process mimics recombination that occurs naturally during sexual reproduction. The first section of Protein Engineering Protocols describes rational p- tein design strategies, including computational methods, the use of non-natural amino acids to expand the biological alphabet, as well as impressive examples for the generation of proteins with novel characteristics. Although procedures for the introduction of mutations have become routine, predicting and und- standing the effects of these mutations can be very challenging and requires profound knowledge of the system as well as protein structures in general.

The de novo design of protein receptors and catalysts requires the development of new and functional polypeptides. As one approach, minimized protein receptors may be abstracted from larger, natural contexts. To explore the utility of employing computational methods for this approach, we experimentally evaluated the previously reported design of a minimal NAD+-binding domain based on the structure of Squalus acanthias lactate dehydrogenase. Synthesis of an appropriate gene and characterization of the resulting protein revealed little secondary structure and no discernible tertiary structure. Evaluation and redesign of the protein using inverse folding methods resulted in only modest improvements. We have attempted to direct the in vitro evolution of artificial antibodies based on alternative protein scaffolds. Diverse libraries of potential receptors were prepared by randomizing two loops in the nucleotide binding site of flavodoxin from Desulfovibrio vulgaris. Selection for novel binding function was then pursued using phage display technology, which mimics the immune system in vitro. The inability to obtain functional receptors by this approach is discussed and future directions are proposed. As an alternative to building new function into existing protein domains, we have also exploited pre-existing function to analyze the determinants of protein structure and to redesign protein architecture. Genetic selection provides a potentially general means of obtaining active catalysts from a diverse population of variants. We show how this tool can be employed for the rapid and sensitive evaluation of protein structure. Through combinatorial mutagenesis and selection, we explored sequence constraints on an interhelical turn in the enzyme chorismate mutase from Escherichia coli. We were able to uncover subtle amino acid preferences not observed in previous studies. In addition, we found that long-range tertiary interactions between residues in a turn and residues elsewhere in the protein can impose a severe constraint on the number of acceptable amino acids at these locations. We exploited genetic selection for the purposes of protein design by transforming the intimately entwined, dimeric chorismate mutase from Methanococcus jannaschii into a monomeric, four-helix-bundle protein with high catalytic activity. The success of this endeavor can be attributed to the choice of a thermostable starting protein, the introduction of point mutations that preferentially destabilize the dimeric structure, and the use of directed evolution to optimize the sequence of an inserted interhelical turn. We found that less than 0.05% of turn sequences yielded well-behaved, monomeric, and highly active proteins. (Abstract shortened by UMI.)

Experimental protein engineering and computational protein design are broad but complementary strategies for developing proteins with altered or novel structural properties and biological functions. By describing cutting-edge advances in both of these fields, Protein Engineering and Design aims to cultivate a synergistic approach to protein science

Biological systems are very special substrates for engineering—uniquely the products of evolution, they are easily redesigned by similar approaches. A simple algorithm of iterative cycles of diversification and selection, evolution works at all scales, from single molecules to whole ecosystems. In the little more than a decade since the first reported applications of evolutionary design to enzyme engineering, directed evolution has matured to the point where it now represents the centerpiece of industrial biocatalyst development and is being practiced by thousands of academic and industrial scientists in com- nies and universities around the world. The appeal of directed evolution is easy to understand: it is conceptually straightforward, it can be practiced without any special instrumentation and, most important, it frequently yields useful solutions, many of which are totally unanticipated. Directed evolution has r- dered protein engineering readily accessible to a broad audience of scientists and engineers who wish to tailor a myriad of protein properties, including th- mal and solvent stability, enzyme selectivity, specific activity, protease s- ceptibility, allosteric control of protein function, ligand binding, transcriptional activation, and solubility. Furthermore, the range of applications has expanded to the engineering of more complex functions such as those performed by m- tiple proteins acting in concert (in biosynthetic pathways) or as part of mac- molecular complexes and biological networks.

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.

Directed evolution comprises two distinct steps that are typically applied in an iterative fashion: (1) generating molecular diversity and (2) finding among the ensemble of mutant sequences those proteins that perform the desired fu- tion according to the specified criteria. In many ways, the second step is the most challenging. No matter how cleverly designed or diverse the starting library, without an effective screening strategy the ability to isolate useful clones is severely diminished. The best screens are (1) high throughput, to increase the likelihood that useful clones will be found; (2) sufficiently sen- tive (i. e. , good signal to noise) to allow the isolation of lower activity clones early in evolution; (3) sufficiently reproducible to allow one to find small improvements; (4) robust, which means that the signal afforded by active clones is not dependent on difficult-to-control environmental variables; and, most importantly, (5) sensitive to the desired function. Regarding this last point, almost anyone who has attempted a directed evolution experiment has learned firsthand the truth of the dictum “you get what you screen for. ” The protocols in Directed Enzyme Evolution describe a series of detailed p- cedures of proven utility for directed evolution purposes. The volume begins with several selection strategies for enzyme evolution and continues with assay methods that can be used to screen enzyme libraries. Genetic selections offer the advantage that functional proteins can be isolated from very large libraries s- ply by growing a population of cells under selective conditions.

A one-stop reference that reviews protein design strategies to applications in industrial and medical biotechnology Protein Engineering: Tools and Applications is a comprehensive resource that offers a systematic and comprehensive review of the most recent advances in the field, and contains detailed information on the methodologies and strategies behind these approaches. The authors—noted experts on the topic—explore the distinctive advantages and disadvantages of the presented methodologies and strategies in a targeted and focused manner that allows for the adaptation and implementation of the strategies for new applications. The book contains information on the directed evolution, rational design, and semi-rational design of proteins and offers a review of the most recent applications in industrial and medical biotechnology. This important book: Covers technologies and methodologies used in protein engineering Includes the strategies behind the approaches, designed to help with the adaptation and implementation of these strategies for new applications Offers a comprehensive and thorough treatment of protein engineering from primary strategies to applications in industrial and medical biotechnology Presents cutting edge advances in the continuously evolving field of protein engineering Written for students and professionals of bioengineering, biotechnology, biochemistry, Protein Engineering: Tools and Applications offers an essential resource to the design strategies in protein engineering and reviews recent applications.

This volume presents a diverse collection of methodologies used to study various problems at the protein sequence and structure level. The chapters in this book look at issues ranging from broad concepts like protein space to specifics like antibody modeling. Topics include point mutations, gene duplication, de novo emergence of new genes, pairwise correlated mutations, ancestral protein reconstruction, homology modelling, protein stability and dynamics, and protein-protein interactions. The book also covers a wide range of computational approaches, including sequence and structure alignments, phylogenies, physics-based and mathematical approaches, machine learning, and more. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and prerequisites, step-by-step, readily reproducible computational protocols (using command line or graphical user interfaces, sometimes including computer code), and tips on troubleshooting and avoiding known pitfalls. Cutting-edge and authoritative, Computational Methods in Protein Evolution is a valuable resource that offers useful workflows and techniques that will help both novice and expert researchers working with proteins computationally.