Natural selection created optimal catalysts. However, optimal performance of enzyme catalysis does not necessarily refer to maximum reaction rate. Rather, it may be a compromise between specificity, rate, stability, and other chemical constraints that makes enzymes capable of catalyzing reactions under mild conditions and with high substrate specificity, accompanied by high regio- and enantioselectivity. The book presented here focuses on the directed evolution of proteins, which has established itself as a powerful method for designing enzymes showing new substrate specificities. It includes a comprehensive repertoire of techniques for producing combinatorial enzyme libraries, while the functional gene expression in a suitable host helps in selecting the appropriate structure, making fast screening a necessity. This book illustrates both the theoretical background as well as the potential of this interesting method in practice - which is becoming ever more important even in classical organic synthesis!
Susanne Brakmann is head of the junior research group "Applied Molecular Evolution" at the University of Leipzig (Germany) and a Member of the Biotechnological--Biomedical Center of Leipzig. She studied Chemistry at the Technical University of Braunschweig where she received her diploma in 1988, moving afterwards to the University of Karlsruhe to work on her thesis under the supervision of Reinhold Tacke (Ph. D. 1991). She was postdoctoral fellow at the Max--Planck--Institute for Biophysical Chemistry in Gottingen where she worked with Manfred Eigen before she moved to Leipzig in 2001. She is interested in directed evolution as a tool for understanding and optimizing enzyme functions, focusing on nucleic acid polymerases and their biotechnological applications. Kai Johnsson is assistant professor for Bioorganic Chemistry at the Swiss Federal Institute for Technology (EPFL) where he heads the laboratory for protein engineering. Prior to joining EPFL, he was a junior group leader at Ruhr--University Bochum in Germany, after spending three and a half years in the laboratory of Prof. Peter G. Schultz (University of California, Berkeley) as a postdoctoral research fellow. Kai Johnsson studied chemistry and did his PhD with Prof. Steven Benner at ETH Zurich. Since the start of his PhD thesis, Kai Johnsson's research interests focus on biological chemistry and in particular enzyme mechanisms and protein chemistry. Prof. Johnsson is the inventor of the Covalys technology.