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Abstract Redox is a unique, programmable modality capable of bridging communication between biology and electronics. Previous studies have shown that theE. coliredox-responsive OxyRS regulon can be re-wired to accept electrochemically generated hydrogen peroxide (H2O2) as an inducer of gene expression. Here we report that the redox-active phenolic plant signaling molecule acetosyringone (AS) can also induce gene expression from the OxyRS regulon. AS must be oxidized, however, as the reduced state present under normal conditions cannot induce gene expression. Thus, AS serves as a “pro-signaling molecule” that can be activated by its oxidation—in our case by application of oxidizing potential to an electrode. We show that the OxyRS regulon is not induced electrochemically if the imposed electrode potential is in the mid-physiological range. Electronically sliding the applied potential to either oxidative or reductive extremes induces this regulon but through different mechanisms: reduction of O2to form H2O2or oxidation of AS. Fundamentally, this work reinforces the emerging concept that redox signaling depends more on molecular activities than molecular structure. From an applications perspective, the creation of an electronically programmed “pro-signal” dramatically expands the toolbox for electronic control of biological responses in microbes, including in complex environments, cell-based materials, and biomanufacturing.
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3D Printed Spectroelectrochemical Platform for Redox‐Based Bioelectronics
Abstract Redox provides unique opportunities for interconverting molecular/biological information into electronic signals. Here, the fabrication of a 3D‐printed multiwell device that can be interfaced into existing laboratory instruments (e.g., well‐plate readers and microscopes) to enable advanced redox‐based spectral and electrochemical capabilities is reported. In the first application, mediated probing is used as a soft sensing method for biomanufacturing: it is shown that electrochemical signal metrics can discern intact mAbs from partially reduced mAb variants (fragmentation), and that these near‐real‐time electrical measurements correlate to off‐line chemical analysis. In the second application,operandospectroelectrochemical measurements are used to characterize a redox‐active catechol‐based hydrogel film: it is shown that electron transfer into/from the film correlates to the molecular switching of the film's redox state with the film's absorbance increasing upon oxidation and the film's fluorescence increasing upon reduction. In the final example, a synthetic biofilm containing redox‐responsiveE. coliis electro‐assembled: it is shown that gene expression can be induced under reducing conditions (via reductive H2O2generation) or oxidative conditions (via oxidation of a phenolic redox‐signaling molecule). Overall, this work demonstrates that 3D printing allows the fabrication of bespoke electrochemical devices that can accelerate the understanding of redox‐based phenomena in biology and enable the detection/characterization redox activities in technology.
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- PAR ID:
- 10569214
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Small Methods
- Volume:
- 9
- Issue:
- 8
- ISSN:
- 2366-9608
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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