(142a) Using Synthetic Biology to Engineer Epistasis to Deter Bacterial Adaptation
Here we present the use of deactivated CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) âCas9 constructs to selectively inhibit or activate sets of multiple genes in Escherichia coli. Simultaneous gene expression perturbations induced in this fashion demonstrate synthetic engineering of epigenetic epistatic interactions â the combined impact of changes in two or more genes on the overall fitness of the cell. We systematically investigate all possible combinations of gene perturbations within two sets of genes. We show strong evidence that as more genes are perturbed, the cellâs ability to adapt decreases as quantified by decreased fitness during antibiotic exposure and a slowed rate of increase in the Minimum Inhibitory Concentration of said antibiotic over time. This work demonstrates a novel approach to engineer control over the emergence of antibiotic resistance through synthetic induction of negative epigenetic epistatic interactions.