The study was published in the journal Joule.
Professor Ardemis Boghossian of EPFL stated that “we engineered E. coli bacteria, the most extensively studied microbe, to generate electricity.”
“Although there are rare bacteria that can generate electricity on their own, they require a specific chemical combination to do so. We have been able to create power in a number of scenarios, including ones involving wastewater because E. coli can thrive on a range of substrates.”
The paper described a revolutionary strategy that has the potential to revolutionise both waste management and energy production.
E. coli bacteria, which are commonly used in biological research, have been used to generate electricity via a mechanism known as extracellular electron transfer (EET). EPFL researchers altered E. coli bacteria to have increased EET, resulting in highly efficient “electric microbes.”Unlike prior approaches, which required specific chemicals to generate energy, the bioengineered E. coli can generate electricity while metabolising a wide range of organic substrates.One of the study’s significant advances is the development of a complete EET pathway within E. coli, which has never been done previously. The researchers successfully developed an optimised pathway that bridges the cell’s inner and outer membranes by merging components from Shewanella oneidensis MR-1, a bacteria known for producing electricity.
When compared to conventional procedures, this innovative pathway outperformed earlier partial approaches, resulting in a threefold increase in electrical current generation.
Importantly, the modified E. coli performed admirably in a variety of conditions, including wastewater collected from a brewery. While other unusual electric bacteria failed, the modified E. coli flourished, demonstrating its potential for large-scale waste treatment and energy generation.
“Instead of putting energy into the system to process organic waste, we are producing electricity while processing organic waste at the same time – hitting two birds with one stone!” said Boghossian.
“We even tested our technology directly on wastewater that we collected from Les Brasseurs, a local brewery in Lausanne. The exotic electric microbes weren’t even able to survive, whereas our bioengineered electric bacteria were able to flourish exponentially by feeding off this waste.”
The implications of the study extend beyond waste treatment. Being abile to generate electricity from a wide range of sources, the engineered E. coli can be utilized in microbial fuel cells, electrosynthesis, and biosensing – to name a few applications. In addition, the bacterium’s genetic flexibility means that it can be tailored to adapt to specific environments and feedstocks, making it a versatile tool for sustainable technology development.
“Our work is quite timely, as engineered bioelectric microbes are pushing the boundaries in more and more real-world applications” said Mouhib, the lead author of the manuscript.
“We have set a new record compared to the previous state-of-the-art, which relied only on a partial pathway, and compared to the microbe that was used in one of the biggest papers recently published in the field. With all the current research efforts in the field, we are excited about the future of bioelectric bacteria, and can’t wait for us and others to push this technology into new scales.”