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Characterizing Electron Transport through Living Biofilms
Published on: June 1, 2018
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Millimeter scale electron conduction through exoelectrogenic mixed species biofilms
Cheng Li1, Keaton Larson Lesnik1, Yanzhen Fan1
1Department of Biological and Ecological Engineering, Oregon State University, 116 Gilmore Hall, Corvallis, OR 97333, USA.
FEMS Microbiology Letters
|June 10, 2016
Summary
Microbial biofilms can transfer electrons via electrical currents over 1 mm, ten times further than previously known. This discovery advances understanding of electron transfer in exoelectrogenic biofilms for microbial electrochemical systems.
Area of Science:
- Microbiology
- Electrochemistry
- Environmental Science
Background:
- Long-distance electron transfer is crucial for natural and engineered systems.
- Exoelectrogenic biofilms were previously thought to transfer electrons only up to 100 μm.
Purpose of the Study:
- To investigate the maximum electron transfer distance in exoelectrogenic biofilms.
- To explore the potential for microbial biofilms to mediate electrical currents over centimeter scales.
Main Methods:
- Developing exoelectrogenic mixed-species biofilms on electrodes with non-conductive gaps ranging from 50 μm to 1 mm.
- Evaluating the in situ conductance of these biofilms over time.
Main Results:
- Exoelectrogenic mixed-species biofilms transferred electrons via electrical currents up to 1 mm.
- This distance is 10 times greater than previously documented for single-species biofilms.
- Interspecies interactions may facilitate spatial development and conductivity in biofilms.
Conclusions:
- Microbial biofilms can conduct electricity over significantly longer distances than previously demonstrated.
- This enhanced conductivity has implications for optimizing microbial electrochemical systems.
- Further research into interspecies interactions is warranted to understand biofilm conductivity.
Keywords:
biofilmconductivityexoelectrogenic bacteriaextracellular electron transfermicrobial fuel cellMore Related Videos
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