Advances in the directed evolution of proteins

• Advances in directed protein evolution during previous biennium are reviewed.
• Technology innovations enable evolution of previously inaccessible properties.
• Rapid selections or protein modifications expand engineering opportunities.
• Combining evolutionary with rational strategies benefits protein engineering.

Natural evolution has produced a great diversity of proteins that can be harnessed for numerous applications in biotechnology and pharmaceutical science. Commonly, specific applications require proteins to be tailored by protein engineering. Directed evolution is a type of protein engineering that yields proteins with the desired properties under well-defined conditions and in a practical time frame. While directed evolution has been employed for decades, recent creative developments enable the generation of proteins with previously inaccessible properties. Novel selection strategies, faster techniques, the inclusion of unnatural amino acids or modifications, and the symbiosis of rational design approaches and directed evolution continue to advance protein engineering.