The year 2024 sees Electriconema, a miniature organism renowned for its electrical conductivity, crowned as the "Microbe of the Year." These microorganisms form intricate chains, reminiscent of cables, capable of reaching five centimeters in length. The Association for General and Applied Microbiology (VAAM) in Frankfurt announced this discovery, revealing that these chains are linked together via electrically conductive protein fibers within their cell envelope.
The structure of the Electronema allows for a specialized division of labor. Thousands of cells reside in the bottom sediment of water bodies, converting sulfide into sulfate. This process generates negatively charged electrons that flow through the protein fibers, ultimately reaching the surface of the sediment, where they combine with oxygen.
This unique bacteria has only been known for a dozen years, but it holds an edge over competing microorganisms in oxygen-free zones due to its ability to consume sulfide. It has been discovered at the bottom of both seas and lakes and has shown potential in reducing methane formation in flooded rice fields, thereby mitigating climate damage.
The developers at VAAM point out that the conductance in the protein fibers of these bacteria resembles that of a metal cable. This makes them an exciting prospect for future advancements in electronics based on biomaterials. While the conductive structures of these bacteria have already been patented, the path to commercial implementation is still underway.
With countless Electronema forming chains, it's no wonder they've captured the attention of microbiologists. Research continues to uncover their incredible capabilities, potentially paving the way for revolutionary developments in technology and environmental science.
Enrichment Insights: The specific electromagnetic properties of Electronema, namely Electriconema aureum GS, have been the subject of intense research. The periplasmic conductive fibers (PCFs) of these bacteria show electrical conductivity exceeding 10 S/cm, comparable to organic semiconductors. These PCFs are made up of multiple strands, which contain iron, sulfur, and nickel that contribute to the fiber's electric conductance.
Further investigation into these fibers has revealed the presence of lamellae-like structures, and vesicle-like inner membrane invaginations below the PCFs. Additionally, these bacteria exhibit an interesting ultrastructure that suggests a potential role for cytochrome proteins in extra/intercellular electron conduction, which could pave the way for novel electronic devices.
Lastly, Electronema's ability to oxidize sulfides, coupled with its oxygen reduction, makes it a promising candidate for water pollution mitigation efforts in certain aquatic ecosystems. By destroying toxic sulfide compounds, these bacteria contribute to a healthier environment.
