A defined mesophilic anaerobic coculture pairing the butyrate-oxidizing syntroph Syntrophomonas wolfei with the hydrogenotrophic methanogen Methanococcus maripaludis. The system is used to study how a fatty acid-oxidizing bacterium and a methanogen synchronize growth, form syntrophic aggregates, and maintain cell-to-cell attraction during methanogenic butyrate conversion. It is relevant to DOE interests in anaerobic carbon cycling, methane production, syntrophic energy sharing, and engineered bioreactor microbiology.
Taxonomy
| Taxon | Ontology ID | Functional Roles | Abundance |
|---|---|---|---|
| Syntrophomonas wolfei | NCBITaxon:863 |
PRIMARY_DEGRADER
SYNTROPHIC_PARTNER
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N/A |
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| Methanococcus maripaludis | NCBITaxon:39152 |
SYNTROPHIC_PARTNER
CROSS_FEEDER
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N/A |
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Ecological Interactions
Syntrophic Butyrate Oxidation and Methanogenesis
SYNTROPHYSource Taxon: Syntrophomonas wolfei
Target Taxon: Methanococcus maripaludis
Metabolites: butyrate (CHEBI:17968), methane (CHEBI:16183)
Biological Processes:
- fatty acid beta-oxidation (GO:0006635)
- methanogenesis (GO:0015948)
Evidence
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PMID:34603271 - SUPPORT (IN_VITRO)"thermodynamically required mutualistic cooperation between fatty acid-oxidizing bacteria and methanogens"
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PMID:34603271 - SUPPORT (IN_VITRO)"butyrate-oxidizing bacteria and methanogens"
Population Ratio Convergence During Growth
MUTUALISMSource Taxon: Syntrophomonas wolfei
Target Taxon: Methanococcus maripaludis
Biological Processes:
- interspecies interaction between organisms (GO:0044419)
Evidence
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PMID:34603271 - SUPPORT (IN_VITRO)"syntrophs and methanogens were inoculated at different initial cell ratios"
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PMID:34603271 - SUPPORT (IN_VITRO)"the cell ratio converged over time to relative constant values"
Syntrophic Aggregation and Cell-to-Cell Attraction
COLONIZATION_FACILITATIONSource Taxon: Syntrophomonas wolfei
Target Taxon: Methanococcus maripaludis
Biological Processes:
- interspecies interaction between organisms (GO:0044419)
Evidence
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PMID:34603271 - SUPPORT (IN_VITRO)"tendency of syntrophic aggregation was not affected by the physical disturbances"
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PMID:34603271 - SUPPORT (IN_VITRO)"suggesting the cell-to-cell attraction between Syntrophomonas and Methanococcus"
Knowledge gaps & discussions (1)
KNOWLEDGE_GAP OPEN Does syntrophic aggregation / cell-to-cell attraction causally enhance butyrate oxidation or methanogenesis in this coculture, and is direct interspecies electron transfer (e.g. the reported carbon-nanotube methane stimulation) involved rather than only H2/formate transfer?
Aggregation and disturbance-resistant cell-to-cell attraction are observed, but no experiment demonstrates that aggregation increases butyrate oxidation or methane production in this exact coculture, so no aggregation→enhancement `downstream` edge was added. Likewise, carbon-nanotube acceleration of methane production is reported, but DIET "does not always explain the enhancement of methane production" and was not directly proven here, so a DIET mechanism is not asserted.
Attaches to: ecological_interactions#Syntrophic Aggregation and Cell-to-Cell Attraction
1 evidence item(s)
suggesting the cell-to-cell attraction between Syntrophomonas and Methanococcus
Attraction/aggregation is observed, but its causal contribution to metabolic performance is untested — the basis for the knowledge gap.
External Resources
| Name | Repository | Resource ID |
|---|---|---|
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Exact-system primary publication - S. wolfei and M. maripaludis growth coordination
Primary publication reporting growth synchronization, aggregation, and cell-to-cell attraction in the S. wolfei and M. maripaludis coculture. |
OTHER | PMID:34603271 |
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Exact-system publication - conductive nanomaterial stimulation
Additional exact-composition publication reporting a defined S. wolfei and M. maripaludis coculture used to test carbon nanotubes and reduced graphene oxide during syntrophic butyrate oxidation. |
OTHER | doi:10.1038/s41598-018-30745-7 |
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DOI landing page - growth coordination publication
DOI landing page for the growth coordination publication. |
OTHER | doi:10.3389/fmicb.2021.742531 |
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NCBI Taxonomy - Syntrophomonas wolfei
NCBI Taxonomy record for Syntrophomonas wolfei. |
OTHER | NCBITaxon:863 |
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NCBI Taxonomy - Methanococcus maripaludis
NCBI Taxonomy record for Methanococcus maripaludis. |
OTHER | NCBITaxon:39152 |
Environmental Factors
| Factor | Value | Unit |
|---|---|---|
| Anoxic methanogenic context | anoxic environments | N/A |
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| Initial partner ratio | variable syntroph-to-methanogen starting ratios | N/A |
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| Physical disturbance | intermittent ultrasound and constant shaking | N/A |
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