Translating Extracellular Electron Transfer Activities with Organic Electrochemical Transistors.

Area of Science:

• Microbiology
• Bioelectronics
• Synthetic Biology

Background:

• Extracellular electron transfer (EET) links microbial metabolism to the environment, with key research models including Geobacter and Shewanella.
• EET-active species are increasingly recognized in fermentation and the human gut microbiome.
• Bridging biological and electronic systems offers potential for novel applications.

Purpose of the Study:

• To develop a protocol for translating microbial EET activity into detectable electrical signals using organic electrochemical transistors (OECTs).
• To demonstrate the biosensing and biocomputing capabilities of a hybrid OECT-microbial system.
• To establish a novel interface between biological systems and electronics.

Main Methods:

• Utilized organic electrochemical transistors (OECTs) with a poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT: PSS) channel.
• Demonstrated EET-driven de-doping of the OECT channel by Shewanella oneidensis.
• Employed transcriptional control of EET flux via genetic circuits for biosensing.
• Integrated plasmid-based Boolean logic gates within microbial cells for signal processing.

Main Results:

• Successfully translated microbial EET activity into measurable electrical signals via OECTs.
• Showcased biosensing of chemical stimuli by controlling EET flux with genetic circuits.
• Demonstrated biocomputing potential through cellular processing of environmental signals using logic gates.
• Established a functional interface between microbial EET and electronic devices.

Conclusions:

• The developed OECT-based system effectively translates microbial EET into electrical signals.
• This hybrid system possesses significant potential for high-throughput screening, biosensing, and biocomputing.
• This work opens new avenues for interfacing biological systems with electronic components.