Directed evolution and rational design

While most enzymes are highly adapted to their natural role, few biocatalysts meet the requirements for industrial applications such as high activity, high stability and excellent selectivity. Modern methods of protein evolution allow the optimisation of enzymes by the alteration of the amino acid sequence and hence the modification of chemical and catalytic properties. This article gives an overview about the strategies rational protein design and directed evolution. The scope and limitations of both methods are outlined by the discussion of very recent examples on the optimisation of stability and selectivity and the creation of novel biocatalysts.