Research
Evolutionary approach to protein analysis and engineering. Random mutagenesis of a starting gene, possibly targeted to a specific segment using available 3D structural information, results in large pools of different mutants. Introduction of such gene libraries into bacteria and exposure of so obtained transformants to harsh environmental conditions allows for selection of beneficial mutants that provide a survival advantage. Enrichment (amplification) and analysis of winner clones after a single evolutionary cycle gives insights into structure-function relationships of the studied macromolecular system. Application of iterative cycles of mutagenesis, selection, and amplification can rapidly evolve variants of functional biological molecules towards better catalytic function or optimized thermal or chemical stability. An increase in selection pressure is usually necessary to augment beneficial traits from round to round as indicated here by the color gradient in the “Selection" segment.
(Directed evolution principle, adapted from Curr. Opin. Struct. Biol. 1997, 7, 470-479 / illustrated by K. Würth & P. Kast, ETH Zurich).
See our research projects that make use of the principle of directed evolution: