|Title||Redox-based synthetic biology enables electrochemical detection of the herbicides dicamba and RoundupTM via rewired Escherichia coli.|
|Publication Type||Journal Article|
|Year of Publication||2019|
|Authors||VanArsdale, E, Tsao, C-Y, Liu, Y, Chen, C-Y, Payne, GF, Bentley, WE|
|Date Published||2019 Apr 16|
Synthetic biology is typically exploited to endow bacterial cells with new biosynthetic capabilities. It can also serve to create "smart" bacteria such as probiotics that detect and treat disease. Here, we show how minimally rewiring the genetic regulation of bacterial cells can enable their ability to recognize and report on chemical herbicides, including those routinely used to clear weeds from gardens and crops. In so doing, we demonstrate how constructs of synthetic biology, in this case redox-based synthetic biology, can serve as a vector for information flow mediating molecular communication between biochemical systems and microelectronics. We coupled the common genetic reporter, β-galactosidase, with the E. coli superoxide response regulon promoter pSoxS, for detection of the herbicides dicamba and Roundup. Both herbicides activated our genetic construct in a concentration dependent manner. Results indicate robust detection using spectrophotometry, via the Miller assay, and electrochemistry using the enzymatic cleavage of 4-aminophenyl β-D-galactopyranoside into the redox active molecule p-aminophenol. We found that environmental components, in particular the availability of glucose, are important factors for the cellular detection of dicamba. Importantly, both herbicides were detected at concentrations relevant for aquatic toxicity.
|Alternate Journal||ACS Sens|