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Electrochemical Detection of Deuterium Kinetic Isotope Effect on Extracellular Electron Transport in Shewanella oneidensis MR-1
Published on: April 16, 2018
Multistep hopping and extracellular charge transfer in microbial redox chains
Sahand Pirbadian1, Mohamed Y El-Naggar
1Department of Physics and Astronomy, University of Southern California, 920 Bloom Walk, Seaver Science Center 215C, Los Angeles, CA 90089-0484, USA.
Physical Chemistry Chemical Physics : PCCP
|July 17, 2012
Summary
Dissimilatory metal-reducing bacteria use microbial nanowires for extracellular electron transfer. A new model explains charge transfer in these microbial redox chains, matching experimental data.
Area of Science:
- Microbiology
- Bioelectrochemistry
- Biophysics
Background:
- Dissimilatory metal-reducing bacteria (DMRB) are crucial in biogeochemical cycles and bioelectrochemical systems.
- Extracellular electron transfer (EET) in DMRB is vital for energy conversion and microbial fuel production.
- Microbial nanowires facilitate conductive pathways for EET in biofilms.
Purpose of the Study:
- To model extracellular charge transfer in microbial redox chains.
- To investigate the role of multistep hopping in microbial nanowires.
- To compare model predictions with experimental current-voltage (I-V) data.
Main Methods:
- Developed a model for charge transfer based on incoherent hopping between redox sites.
- Incorporated an interfacial treatment for electrochemical interactions with electrodes.
- Measured I-V characteristics across and along individual microbial nanowires of Shewanella oneidensis MR-1.
Main Results:
- The model accurately predicted I-V characteristics of microbial nanowires.
- Calculated I-V data showed good agreement with experimental measurements.
- Demonstrated the viability of multistep hopping for efficient charge transfer.
Conclusions:
- Multistep hopping in redox chains is a feasible mechanism for EET in microbial biofilms.
- The developed model provides insights into the biophysics of microbial electron transport.
- This research advances understanding of microbial energy conversion in bioelectrochemical systems.
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