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bioRxiv · 10.1101/866319

A Highly-ordered and Fail-safe Electrical Network in Cable Bacteria

Bonne, R.·Thiruvallur Eachambadi, R.·Cornelissen, R.·Hidalgo-Martinez, S.·Vangronsveld, J.·Meysman, F. J. R.·Valcke, R.·Cleuren, B.·Manca, J. V.
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Abstract

Cable Bacteria are an emerging class of electroactive organisms that sustain unprecedented long-range electron transport across centimeter-scale distances. The pathways of the electrical currents in these filamentous microorganisms remain unresolved. Here, the electrical circuitry in a single cable bacterium is visualized with nanoscopic resolution using Conductive Atomic Force Microscopy. Combined with perturbation experiments, it is demonstrated that electrical currents are conveyed through a parallel network of conductive fibers embedded in the cell envelope which are electrically interconnected between adjacent cells. This redundant structural organization of electrical pathways likely forms a crucial adaptive trait for organisms capable of long-distance electron transport. The observed electrical circuit architecture is unique in biology and could inspire future technological applications in bioelectronics.

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Bonne, R., Thiruvallur Eachambadi, R., Cornelissen, R., Hidalgo-Martinez, S., Vangronsveld, J., Meysman, F. J. R., Valcke, R., Cleuren, B., Manca, J. V.. 2019-12-10. A Highly-ordered and Fail-safe Electrical Network in Cable Bacteria. https://doi.org/10.1101/866319

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