Fig. 5: Cell-free biosensor for detection of naltrexone and quinine.
From: Highly multiplexed design of an allosteric transcription factor to sense new ligands
a Cell-free expression system consisting of a sensor plasmid and an sfGFP reporter plasmid whose expression is mediated by ligand binding by the sensor. b The plasmid encoding 3A7 TtgR (sensor plasmid) was titrated against 5 nM of the plasmid encoding sfGFP regulated by 3A7 TtgR (reporter plasmid) in cell-free gene expression reactions. c 6 nM of the 3A7 sensor plasmid and 2 nM reporter plasmid were added to cell-free gene expression reactions and incubated with naltrexone at log-fold increments. d 2F9 TtgR sensor plasmid was titrated against 5 nM reporter plasmid in cell-free gene expression reactions. e 4 nM 2F9 TtgR sensor plasmid and 2 nM reporter plasmid were added to cell-free gene expression reactions and incubated with indicated concentrations of quinine. Reported are the sfGFP concentrations normalized to a FITC standard over 18-h experiment at 30 °C, continuously monitored every 10 min. Data for (b–e) are presented as mean values ± SD of three independent replicates. Source data are provided as a Source Data file.
