Real-time environmental monitoring of contaminants using living electronic sensors

Atkinson, J. T.; Su, L.; Zhang, X.; Bennett, G. N.; Silberg, J.; Ajo-Franklin, C.

doi:10.1101/2021.06.04.447163

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bioRxiv · 10.1101/2021.06.04.447163

Real-time environmental monitoring of contaminants using living electronic sensors

Atkinson, J. T.·Su, L.·Zhang, X.·Bennett, G. N.·Silberg, J.·Ajo-Franklin, C.

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Abstract

Real-time chemical sensing is needed to counter the global threats posed by pollution. We combine synthetic biology and materials engineering to develop a living bioelectronic sensor platform with minute detection times. Escherichia coli was programmed to reduce an electrode in a chemical-dependent manner using a modular, eight-component, synthetic electron transport chain. This strain produced significantly more current upon exposure to thiosulfate, an anion that causes microbial blooms. Incorporating a protein switch into the synthetic pathway and encapsulation of microbes with electrodes and conductive nanomaterials yielded a living bioelectronic sensor that could detect an endocrine disruptor within two minutes in riverine water, implicating the signal as mass transfer limited. These findings provide a new platform for miniature, low-power sensors that safeguard ecological and human health. One Sentence SummaryChemicals are detected electrically using an allosterically-regulated electron transfer pathway in designer microbes.

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Atkinson, J. T., Su, L., Zhang, X., Bennett, G. N., Silberg, J., Ajo-Franklin, C.. 2021-06-04. Real-time environmental monitoring of contaminants using living electronic sensors. https://doi.org/10.1101/2021.06.04.447163

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