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bioRxiv · 10.1101/2024.07.19.604230

Disentangling the regulatory response of Agrobacterium tumefaciens CHLDO to glyphosate for engineering whole-cell phosphonate biosensors

Masotti, F.·Krink, N.·Lencina, N.·Gottig, N.·Ottado, J.·Nikel, P. I.
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Abstract

AO_SCPLOWBSTRACTC_SCPLOWPhosphonates (PHTs), organic compounds with a stable C--P bond, are widely distributed in nature. Glyphosate (GP), a synthetic PHT, is extensively used in agriculture and has been linked to various human health issues and environmental damage. Given the prevalence of GP, developing cost-effective, on-site methods for GP detection is key for assessing pollution and reducing exposure risks. We adopted Agrobacterium tumefaciens CHLDO, a natural GP degrader, as the source of genetic parts for constructing PHT biosensors. In this species, the phn gene cluster, encoding the C--P lyase pathway, is regulated by the PhnF transcriptional repressor and is part of the Pho regulon. We selected the phnG promoter, which displays a dose-dependent response to GP, to build a set of whole-cell biosensors. Through stepwise optimization of the transcriptional cascade, we created a biosensor capable of detecting GP in the 0.25-50 M range in various samples, including soil and water.

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Masotti, F., Krink, N., Lencina, N., Gottig, N., Ottado, J., Nikel, P. I.. 2024-07-19. Disentangling the regulatory response of Agrobacterium tumefaciens CHLDO to glyphosate for engineering whole-cell phosphonate biosensors. https://doi.org/10.1101/2024.07.19.604230

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