An engineered lactate responding promoter system operating in glucose-rich and anaerobic environments.

Zuniga, A.; Chang, H.-J.; Fristot, E.; Bonnet, J.

doi:10.1101/2021.01.06.425364

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bioRxiv · 10.1101/2021.01.06.425364

An engineered lactate responding promoter system operating in glucose-rich and anaerobic environments.

Zuniga, A.·Chang, H.-J.·Fristot, E.·Bonnet, J.

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Abstract

Bacteria equipped with genetically-encoded lactate biosensors would support several applications in biopharmaceutical production, diagnosis, or therapeutics. However, many applications involve glucose-rich and anaerobic environments, in which current whole-cell lactate biosensors have low performance. Here we engineered a synthetic lactate biosensor system by repurposing the natural LldPRD promoter regulated by the LldR transcriptional regulator. We removed glucose catabolite repression by designing a hybrid promoter, containing LldR operators and tuned both regulator and reporter gene expression to optimize biosensor signal-to-noise ratio. The resulting lactate biosensor, termed ALPaGA (A Lactate Promoter Operating in Glucose and Anaerobia) can operate in glucose rich, aerobic and anaerobic conditions. Our work provides a versatile lactate biosensing platform suitable for many environmental conditions.

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Zuniga, A., Chang, H.-J., Fristot, E., Bonnet, J.. 2021-01-06. An engineered lactate responding promoter system operating in glucose-rich and anaerobic environments.. https://doi.org/10.1101/2021.01.06.425364

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