A synthetic biology approach to integrated circuits for the directed evolution and selection of new protein specificity in vivo

Ben P. Mackrow, Marko Storch, Tom Adie, Geoff S. Baldwin*

â? These authors contributed equally to this work

Department of Life Sciences, Imperial College, South Kensington Campus, London, SW7 2AZ, UK
*To whom correspondence should be addressed:
g.baldwin@imperial.ac.uk

ABSTRACT

Synthetic biology seeks to engineer new and more complex biological systems that can detect and respond to external stimuli. This will lead to an increased requirement for new biological specificity that goes beyond what is available in nature. To this end we have developed a new method for the accelerated evolution and selection of novel biological function in vivo. Current methods for directed evolution typically rely on in vitro methods to introduce genetic variation, followed by in vivo screening, which is both time consuming and limiting in terms of genetic space that can be explored. We here demonstrate a method to target mutation to a specific gene within E. coli, thus opening up the possibility for combined mutation and selection within a single chassis. This is currently being deployed with gene circuitry for the integrated direct evolution and selection of new bacterial signalling systems.