Inspenet, September 14, 2023.
One of the most significant advances has occurred in energy production, specifically from a clean and sustainable source: the generation of electricity through bacteria.
A team of researchers from the Federal Polytechnic School of Lausanne, located in Switzerland, has managed to improve the ability of the Escherichia coli bacteria to generate electricity. This innovative approach not only offers an environmentally friendly solution for organic waste treatment, but also outperforms leading technologies in the field.
“We modified E. coli, the most studied microbe, to generate electricity,” says study leader Ardemis Boghossian. “Although there are exotic microbes that produce electricity naturally, they can only do so in the presence of specific chemicals. It can grow in a wide range of sources, which allowed us to produce electricity in different environments, including from wastewater.”
A powerful bacteria for generating electricity
The aforementioned bacteria have been used to generate electricity through a process called extracellular electron transfer (EET). The team led by Boghossian made modifications to improve its EET capacity, transforming it into highly effective microorganisms in the production of electrical energy. Unlike previous approaches that relied on specific chemicals to generate electricity, genetically engineered E. coli can generate energy while metabolizing various organic substrates.
A key innovative aspect of this study lies in the creation of a complete EET pathway within E. coli, an achievement that had not been previously achieved. By incorporating elements from Shewanella oneidensis MR-1 (a bacteria renowned for its ability to generate electricity), the researchers successfully built an optimized pathway that spans both the inner and outer membranes of the cell.
It is relevant to highlight that the modified E. coli demonstrated outstanding performance in different conditions, even when wastewater from a brewery was used. While other rare electric bacteria faced difficulties, this one thrived, highlighting its ability to be effective in treating waste and generating energy on a considerable scale.
“Instead of putting energy into the system to process organic waste, we are producing electricity while processing organic waste at the same time, killing two birds with one stone,” Boghossian said. “We even tested our technology directly on wastewater we collected from Les Brasseurs, a local brewery in Lausanne. The electric microbes couldn’t even survive, while our bioengineered electric bacteria were able to flourish exponentially by feeding on this waste.”
The consequences of this research transcend the field of waste treatment . Given its potential to generate electricity from various sources, this modified organism can be applied in a variety of fields, including microbial fuel cells, electrosynthesis, and biological sensing, among other applications. Furthermore, its ability to genetically adapt to specific environments and raw materials makes it a versatile tool for the advancement of sustainable technologies.