On a Robust, Sensitive Cell – Free Method for Pseudomonas Sensing and Quantification

Cell – free lysates have found a utility in performing cellular functions and providing biologically-relevant metabolic products without the optimal biological conditions for growth and proliferation. By teasing out the biological components and constructing artificial conditions that enable for biological transcription and translation processes to occur, specific cell - like functions can be reconstituted in vitro without requiring the entire cell and milieu of cellular organelles. This enables for optimization of biological circuits, either by concentration or on/off switches, simply through the addition or removal of genetic components (plasmids, inducers, or repressors) of regulatory elements. Here, we demonstrate an application of cell – free process that is robust and portable, independent of a substrate, to apply for sensing and reporting functions of a quorum sensing molecule N-3-oxododecanoyl homoserine lactone (3OC12HSL) found crucial for pathological Pseudomonas infections. Using droplet microfluidics to integrate cell – free related functions into hydrogel scaffolds, we show that these cell - free circuits can be encapsulated, delivered, and activated in most environments—even in conditions with very little hydration.