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bioRxiv · 10.1101/2021.10.21.465235

Engineering transcription factor BmoR mutants for constructing multifunctional alcohol biosensors

Wu, T.·Chen, Z.·Zhang, C.·Huo, Y.-X.
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Abstract

Native transcription factor-based biosensors (TFBs) have the potential for in situ detection of value-added chemicals or byproducts. However, their industrial application is limited by their ligand promiscuity, low sensitivity, and narrow detection range. Alcohols exhibit similar structures, and no reported TFB can distinguish a specific alcohol from its analogs. Here, we engineered an alcohol-regulated transcription factor, BmoR, and obtained various mutants with remarkable properties. For example, the generated signal-molecule-specific BmoRs could distinguish the constitutional isomers n-butanol and isobutanol, with insensitivity up to an ethanol concentration of 800 mM (36.9 g/L). Linear detection of 0-60 mM of a specific higher alcohol could be achieved in the presence of up to 500 mM (23.0 g/L) ethanol as background noise. Notably, two mutants with raised outputs and over 1.0 x 107-fold higher sensitivity, and one mutant with an increased upper detection limit (14.8 g/L n-butanol or isobutanol) were screened out. Using BmoR as an example, this study systematically explored the ultimate detection limit of a TFB towards its small-molecule ligands, paving the way for in situ detection in the biofuel and wine industries.

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Wu, T., Chen, Z., Zhang, C., Huo, Y.-X.. 2021-10-21. Engineering transcription factor BmoR mutants for constructing multifunctional alcohol biosensors. https://doi.org/10.1101/2021.10.21.465235

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