Pseudomonas aeruginosa glutamyl-tRNA synthetase (GluRS) was overexpressed in Escherichia coli. Sequence analysis indicated that P. aeruginosa GluRS is a discriminating GluRS and, similar to other GluRS proteins, requires the presence of tRNAGlu to produce a glutamyl-AMP intermediate. Kinetic parameters for interaction with tRNA were determined and the kcat and KM were 0.8 s−1 and 0.68 µM, respectively, resulting in a kcat/KM of 1.18 s−1 µM−1. A robust aminoacylation-based scintillation proximity assay (SPA) assay was developed and 800 natural products and 890 synthetic compounds were screened for inhibitory activity against P. aeruginosa GluRS. Fourteen compounds with inhibitory activity were identified. IC50s were in the low micromolar range. The minimum inhibitory concentration (MIC) was determined for each of the compounds against a panel of pathogenic bacteria. Two compounds, BT_03F04 and BT_04B09, inhibited GluRS with IC50s of 21.9 and 24.9 µM, respectively, and both exhibited promising MICs against Gram-positive bacteria. Time-kill studies indicated that one compound was bactericidal and one was bacteriostatic against Gram-positive bacteria. BT_03F04 was found to be noncompetitive with both ATP and glutamic acid, and BT_04B09 was competitive with glutamic acid but noncompetitive with ATP. The compounds were not observed to be toxic to mammalian cells in MTT assays.

Implementing stable electronic components on smart, soft materials can facilitate increasingly complex functionality in body‐worn and implanted devices for biomedical applications. The fabrication and characterization of indium–gallium–zinc oxide (IGZO)‐based Schottky diodes on a thiol–ene/acrylate shape memory polymer (SMP) that softens in response to physiological stimuli, including temperature and moisture, are presented. A platinum–IGZO Schottky junction is formed on the softening polymer assisted by ultraviolet‐ozone (UV‐O3) surface treatment. The effects of the UV‐O3 treatment conditions on the Schottky barrier properties are examined. The diode operation is evaluated in dry and wet conditions with varying temperatures up to 75 °C, revealing that the fabricated diodes preserve their performance even after the softening effect (i.e., an orders‐of‐magnitude modulus change) is induced in the polymer substrate. Additionally, high‐frequency diode operation up to 1 GHz is demonstrated for devices with an active area of 10 000 µm2 at 0 V bias. These devices can serve as building blocks for high‐frequency rectifying circuits and in more sophisticated arrangements toward applications in, for example, wireless bioelectronic implants.

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