Efficient long-range conduction in cable bacteria through nickel protein wires
![Loading Loading](https://www.biorxiv.org/sites/all/modules/contrib/panels_ajax_tab/images/loading.gif)
Abstract
Filamentous cable bacteria display unrivalled long-range electron transport, generating electrical currents over centimeter distances through a highly ordered network of fibers embedded in their cell envelope. The conductivity of these periplasmic wires is exceptionally high for a biological material, but their chemical structure and underlying electron transport mechanism remain unresolved. Here, we combine high-resolution microscopy, spectroscopy, and chemical imaging on individual cable bacterium filaments to demonstrate that the periplasmic wires consist of a conductive protein core surrounded by an insulating shell layer. The core proteins contain a sulfur-ligated nickel cofactor, and conductivity decreases when nickel is oxidized or selectively removed. The involvement of nickel as the active metal in biological conduction is remarkable, and suggests a hitherto unknown form of electron transport that enables efficient conduction in centimeter-long protein structures.
Competing Interest Statement
The authors have declared no competing interest.
Subject Area
- Biochemistry (11740)
- Bioengineering (8750)
- Bioinformatics (29189)
- Biophysics (14967)
- Cancer Biology (12093)
- Cell Biology (17410)
- Clinical Trials (138)
- Developmental Biology (9420)
- Ecology (14178)
- Epidemiology (2067)
- Evolutionary Biology (18301)
- Genetics (12239)
- Genomics (16797)
- Immunology (11865)
- Microbiology (28070)
- Molecular Biology (11583)
- Neuroscience (60953)
- Paleontology (451)
- Pathology (1870)
- Pharmacology and Toxicology (3238)
- Physiology (4957)
- Plant Biology (10425)
- Synthetic Biology (2884)
- Systems Biology (7338)
- Zoology (1651)