Methods for the directed evolution of proteins

Directed evolution has proved to be an effective strategy for improving or altering the activity of biomolecules for industrial, research and therapeutic applications. The evolution of proteins in the laboratory requires methods for generating genetic diversity and for identifying protein variants with desired properties. This Review describes some of the tools used to diversify genes, as well as informative examples of screening and selection methods that identify or isolate evolved proteins. We highlight recent cases in which directed evolution generated enzymatic activities and substrate specificities not known to exist in nature.

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Acknowledgements

This work was supported by the US Defense Advanced Research Projects Agency grants DARPA HR0011-11-2-0003 and DARPA N66001-12-C-4207, the US National Institutes of Health (NIH)/National Institute of General Medical Sciences (NIGMS) (grant R01 GM095501) and the Howard Hughes Medical Institute (HHMI).