Fig. 5.

Toward the deployment of two-component sensors for real-world sensing. (A) The cell-free expressed NarX-L system can be encapsulated into giant unilamellar vesicles. (B) Signaling and subsequent mEGFP expression can be visualized on the microscope (Top). Rhodamine-labeled membranes are colored in red, and mEGFP are colored in green. (Scale bars are 10 µm.) Expression of luciferase inside giant unilamellar vesicles can be detected in bulk solution (Bottom). (C) Lyophilized reactions remain active, following rehydration with nonideal media. (D) NarX-L enables higher expression in the presence of 100 µM nitrate compared to the absence of nitrate when rehydrated in Milli-Q water, lake water, and 50% FBS following lyophilization. Fold change in luminescence in response to nitrate relative to water is indicated above each condition. All error bars represent the SEM for n = 3 independent replicates.