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bioRxiv · 10.64898/2026.06.19.733485

Orthogonal Acoustic Control of Gene Expression Using a Synthetic T7RNAP Rapa-Inducible Dimerization System

Zhang, H.·Schroeder, A.·Xu, P.
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Abstract

Precise spatiotemporal regulation of engineered microbes remains a critical bottleneck in synthetic biology. While ultrasound is extensively utilized for imaging and drug delivery, its translation into bacterial chassis is hindered by the lack of stringent biochemical triggers. Here, we present a rationally designed, ultrasound-responsive hybrid molecular switch based on a strict acoustic-biochemical "AND-gate". We engineered a highly sensitive split-T7 RNA polymerase system, which the dimerization and subsequent gene transcription can only be triggered in the presence of both ultrasound and a PEG-modified rapamycin. By systematically optimizing the acoustic parameters, we deployed this spatiotemporal switch to dynamically regulate a microbial consortium. With lysisE suicide protein as the output module, we achieved precise and programmable tuning of bacterial population in a co-culture system. This acoustic gating strategy may provide a robust and versatile toolkit for complex microbiome engineering and dynamic biomanufacturing. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=158 SRC="FIGDIR/small/733485v1_ufig1.gif" ALT="Figure 1"> View larger version (41K): org.highwire.dtl.DTLVardef@6d229corg.highwire.dtl.DTLVardef@fb5d1eorg.highwire.dtl.DTLVardef@9e905dorg.highwire.dtl.DTLVardef@17e3a1_HPS_FORMAT_FIGEXP M_FIG Graphic Abstract C_FIG

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Zhang, H., Schroeder, A., Xu, P.. 2026-06-22. Orthogonal Acoustic Control of Gene Expression Using a Synthetic T7RNAP Rapa-Inducible Dimerization System. https://doi.org/10.64898/2026.06.19.733485

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