Investigation of microbial long-distance electron transport via spectroscopy and electrochemistry.

Recently, long filamentous bacteria have been discovered in marine sediments, which are capable of generating and mediating electricity over centimeter-scale distances. These so-called "cable bacteria" have evolved a new mechanism for mediating electrical currents, which extends the known length scale of microbial electron transmission by two orders of magnitude. Cable bacteria are multi-cellular and possess a unique energy metabolism, in which electrons are passed on from cell to cell along a chain of 10.000 cells. This biological innovation equips them with a competitive advantage for survival within the seafloor environment. Microbial long-distance electron transport is a disruptive finding, both in terms of new biology as well as potential new technology. The capability of cable bacteria to transport electrons over centimeter distances implies that biological evolution must have somehow developed a highly conductive, organic structure. If these conductive structures inside cable bacteria could be somehow harnessed in an engineered way, this could pave the way for entirely new materials and applications in bio-electronics. To better grasp the wide reaching implications of long-distance electron transport, we need to better understand how the phenomenon works. Here, science is faced with an important challenge: it remains a conundrum how electrons are transported through a cable bacterium. Therefore, the prime objectives of this project are (1) to resolve the conductive structures and mechanism responsible for microbial long-distance transport and (2) to characterize their physical structure, chemical composition and electrical properties. The foundational pillar of this project are recently acquired data demonstrating that cable bacteria can be connected to electrodes and revealing that the cell envelope of cable bacteria contains highly conductive structures.

Keywords:MICROBIAL ECOLOGY

Disciplines:Microbiology not elsewhere classified, Biomaterials