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Updated: Jun 24, 2026
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Characterizing Mediated Extracellular Electron Transfer in Lactic Acid Bacteria with a Three-Electrode, Two-Chamber Bioelectrochemical System
Published on: August 23, 2024
Lactobacillus plantarum WCFS1 electron transport chains.
R J W Brooijmans1, W M de Vos, J Hugenholtz
1TI Food and Nutrition, Kluyver Centre for Genomics of Industrial Fermentation, BA Ede, The Netherlands.
Applied and Environmental Microbiology
|April 7, 2009
Summary
Lactobacillus plantarum WCFS1 uses heme and menaquinone for aerobic respiration. These compounds enable nitrate reduction, but high glucose inhibits this process, unlike mannitol.
Area of Science:
- Microbiology
- Bacterial Physiology
Background:
- Lactobacillus plantarum WCFS1 respiration is poorly understood.
- Aerobic respiration requires specific cofactors like heme and menaquinone.
Purpose of the Study:
- To investigate the role of heme and menaquinone in L. plantarum WCFS1 aerobic respiration.
- To identify genes involved in respiration and nitrate reduction.
- To explore the effect of growth substrates on nitrate metabolism.
Main Methods:
- Supplementation of growth media with heme and menaquinone.
- Measurement of biomass production and oxygen consumption.
- Analysis of nitrate reduction activity under different substrate conditions.
- Identification and characterization of relevant genes (cydABCD, narGHJI, ndh1) using isogenic mutants.
Main Results:
- Heme and menaquinone addition enhanced L. plantarum WCFS1 biomass and oxygen consumption.
- Both compounds enabled nitrate reduction, producing nitrite and ammonia.
- High glucose concentrations inhibited nitrate reduction, while mannitol did not.
- Genes cydA, ndh1, and narG were essential for respiration-like behavior and nitrate reduction, respectively.
Conclusions:
- L. plantarum WCFS1 possesses a branched electron transport chain for aerobic respiration and nitrate reduction.
- Heme and menaquinone are crucial for this respiratory activity.
- Substrate availability, particularly glucose levels, significantly impacts nitrate metabolism.
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