Engineering Sensors to Facilitate Multiplex Tuning of Biosynthetic Pathways
Metabolic pathways comprise several enzymes that progressively modify precursor molecules, resulting in a final product. Varying the expression level of each component enzyme results in tradeoffs of metabolic load, enzymatic flux, and buildup of intermediates. Therefore, in order to maximize the yield of a pathway, the optimal level of each enzyme must be determined. In this work we present a novel method for rapid exploration of such an expression landscape. Each component gene is placed under the control of a different, orthogonal small-molecule inducible system. Adjusting the concentration of each inducer alters the expression of each gene, and the entire expression landscape can be probed using a single genetic construct. In order to facilitate this approach, we continue to expand the number of inducible systems with the orthogonality and dynamic range necessary for such a system to function.