Article | Published:

Tunable thermal bioswitches for in vivo control of microbial therapeutics

Nature Chemical Biology volume 13, pages 7580 (2017) | Download Citation

Abstract

Temperature is a unique input signal that could be used by engineered microbial therapeutics to sense and respond to host conditions or spatially targeted external triggers such as focused ultrasound. To enable these possibilities, we present two families of tunable, orthogonal, temperature-dependent transcriptional repressors providing switch-like control of bacterial gene expression at thresholds spanning the biomedically relevant range of 32–46 °C. We integrate these molecular bioswitches into thermal logic circuits and demonstrate their utility in three in vivo microbial therapy scenarios, including spatially precise activation using focused ultrasound, modulation of activity in response to a host fever, and self-destruction after fecal elimination to prevent environmental escape. This technology provides a critical capability for coupling endogenous or applied thermal signals to cellular function in basic research, biomedical and industrial applications.

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Acknowledgements

The authors thank J. Szablowski for assistance with focused ultrasound, A. Mukherjee, J. Bois and A. Gluhovsky for helpful discussions, and S. Zemsky, R. Rezvani, Y. Jiang and G. Ha for experimental assistance. D.I.P. was supported by the NIH fellowship for Predoctoral Training in Biology and Chemistry (T32GM007616). M.H.A. was supported by an NSF graduate research fellowship and the Paul and Daisy Soros Fellowship for New Americans. This work was supported by a DARPA Young Faculty Award (D14AP00050), the Weston Havens Foundation, a Burroughs Wellcome Career Award at the Scientific Interface and the Heritage Medical Research Institute (M.G.S.).

Author information

Author notes

    • Dan I Piraner
    •  & Mohamad H Abedi

    These authors contributed equally to this work.

Affiliations

  1. Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California, USA.

    • Dan I Piraner
    • , Mohamad H Abedi
    • , Brittany A Moser
    • , Audrey Lee-Gosselin
    •  & Mikhail G Shapiro
  2. Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California, USA.

    • Dan I Piraner
    •  & Mohamad H Abedi

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Contributions

D.I.P. co-conceived and planned the study, generated genetic constructs, evaluated their performance in vitro and in vivo, and co-wrote the manuscript. M.H.A. co-conceived and planned the study, generated genetic constructs, evaluated their performance in vitro and in vivo, and co-wrote the manuscript. B.A.M. generated genetic constructs and evaluated their performance in vitro. A.L.-G. conducted in vivo experiments. M.G.S. co-conceived and supervised the study and co-wrote the manuscript. All authors provided input on the final manuscript.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Mikhail G Shapiro.

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    Supplementary Text and Figures

    Supplementary Results, Supplementary Tables 1–3 and Supplementary Figures 1–7.

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DOI

https://doi.org/10.1038/nchembio.2233

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