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bioRxiv · 10.1101/786533

Light-Inducible Recombinases for Bacterial Optogenetics

Sheets, M. B.·Wong, W.·Dunlop, M. J.
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Abstract

Optogenetic tools can provide direct and programmable control of gene expression. Light-inducible recombinases, in particular, offer a powerful method for achieving precise spatiotemporal control of DNA modification. However, to-date this technology has been largely limited to eukaryotic systems. Here, we develop optogenetic recombinases for Escherichia coli which activate in response to blue light. Our approach uses a split recombinase coupled with photodimers, where blue light brings the split protein together to form a functional recombinase. We tested both Cre and Flp recombinases, Vivid and Magnet photodimers, and alternative protein split sites in our analysis. The optimal configuration, Opto-Cre-Vvd, exhibits strong blue light-responsive excision and low ambient light sensitivity. For this system we characterize the effect of light intensity and the temporal dynamics of light-induced recombination. These tools expand the microbial optogenetic toolbox, offering the potential for precise control of DNA excision with light-inducible recombinases in bacteria.

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Sheets, M. B., Wong, W., Dunlop, M. J.. 2019-09-30. Light-Inducible Recombinases for Bacterial Optogenetics. https://doi.org/10.1101/786533

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