Scientific research has always had the ability to amaze us, bringing unexpected phenomena to light. The latest is a virus, genetically manipulated, which turns out to be a promising source of electricity. The team of Seung Wuk Lee, bioengineer at the University of California at Berkeley, showed how M13 bacteriophages, viruses that infect bacteria, can be induced to become small “power plants.”
Origins of biological electric currents
The concept of bioelectricity is not new. Already in the 18th century Italian Luigi galvani demonstrated how electrical impulses could induce muscle contractions in frogs, laying the foundations of electrophysiology. However, detailed understanding of these phenomena at the molecular level has remained a mystery until now.
The M13 bacteriophage has a unique structure, “adorned” by a protein sheath composed of almost 3.000 copies of a helical protein. This arrangement creates a polarity, with positive charges on the inside and negative charges on the outside. Lee's team previously found that applying pressure on these proteins generated them piezoelectricity, or the ability to transform mechanical force into electrical energy.
Generation of electric currents using heat
By genetically modifying viruses to include a specific protein sequence, the researchers got them to bind to thin nickel-coated plates. By exposing these structures to heat (either through fire or a laser), the proteins melt and fold, unbalancing the charges and generating electrical voltages.
This process, known as pyroelectricity, was further enhanced by the insertion of glutamate, a negatively charged amino acid, on the outer surface of the proteins. You can find here more information on the study done.
Practical applications
The research paves the way for several practical applications. One of these is the use of bacteriophages as biosensors to detect harmful gases. By exploiting their ability to generate specific electrical signatures in the presence of certain chemicals, such as xylene, viruses can prove to be effective tools in the detection of dangerous substances.
Although the tension generated by viruses is still modest, researchers are optimistic about the possibility of amplifying it. M13 viruses have the ability to self-replicate, increasing their number and, consequently, the intensity of the electrical energy produced.
We'll see. This research not only highlights the importance of bioengineering in sustainable energy production, but also opens new perspectives on understanding and using biological electricity. The work of Lee and his team reminds us (if any were still needed) that the most innovative solutions can come from the most unexpected sources.
