The organo-metal-like nature of long-range conduction in cable bacteria

Bioelectrochemistry. 2024 Feb 25;157:108675. doi: 10.1016/j.bioelechem.2024.108675. Online ahead of print.ABSTRACTCable bacteria are filamentous, multicellular microorganisms that display an exceptional form of biological electron transport across centimeter-scale distances. Currents are guided through a network of nickel-containing protein fibers within the cell envelope. Still, the mechanism of long-range conduction remains unresolved. Here, we characterize the conductance of the fiber network under dry and wet, physiologically relevant, conditions. Our data reveal that the fiber conductivity is high (median value: 27 S cm-1; range: 2 to 564 S cm-1), does not show any redox signature, has a low thermal activation energy (Ea = 69 ± 23 meV), and is not affected by humidity or the presence of ions. These features set the nickel-based conduction mechanism in cable bacteria apart from other known forms of biological electron transport. As such, conduction resembles that of an organic semi-metal with a high charge carrier density. Our observation that biochemistry can synthesize an organo-metal-like structure opens the way for novel bio-based electronic technologies.PMID:38422765 | DOI:10.1016/j.bioelechem.2024.108675

Source: Bioelectrochemistry - February 29, 2024 Category: Biochemistry Authors: Dmitrii Pankratov Silvia Hidalgo Martinez Cheryl Karman Anastasia Gerzhik Gabriel Gomila Stanislav Trashin Henricus T S Boschker Jeanine S Geelhoed Dirk Mayer Karolien De Wael Filip J R Meysman Source Type: research