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bioRxiv · 10.1101/2020.10.30.362871

Inducible Directed Evolution of Complex Phenotypes in Bacteria

Al'Abri, I. S.·Haller, D.·Crook, N. C.
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Abstract

Directed evolution is a powerful method for engineering biology in the absence of detailed sequence-function relationships. To enable directed evolution of complex phenotypes encoded by multigene pathways, we require large library sizes for DNA sequences >5-10kb in length, elimination of genomic hitchhiker mutations, and decoupling of diversification and screening steps. To meet these challenges, we developed Inducible Directed Evolution (IDE), which uses a temperate bacteriophage to package large plasmids and transfer them to naive cells after intracellular mutagenesis. To demonstrate IDE, we evolved a 5-gene pathway from Bacillus licheniformis that accelerates tagatose catabolism in Escherichia coli, resulting in clones with 65% shorter lag times during growth on tagatose after only two rounds of evolution.

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Al'Abri, I. S., Haller, D., Crook, N. C.. 2020-10-31. Inducible Directed Evolution of Complex Phenotypes in Bacteria. https://doi.org/10.1101/2020.10.30.362871

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