A syntrophic, obligate two-member anaerobic consortium consisting of Syntrophobacter fumaroxidans, which oxidizes propionate to acetate, and Methanobacterium formicicum, a hydrogen and formate-utilizing methanogen. S. fumaroxidans degrades propionate via the methylmalonyl-CoA pathway only in coculture with H2/formate-using archaea, as it uses protons as the electron acceptor with H2 and formate as electron sink products. The removal of H2 and formate by M. formicicum is thermodynamically essential for continued propionate oxidation by S. fumaroxidans. This syntrophic relationship is fundamental to understanding methane production from propionate in anaerobic environments such as digesters, sediments, and wastewater treatment systems, playing a critical role in biogeochemical cycling.
Taxonomy
| Taxon | Ontology ID | Functional Roles | Abundance |
|---|---|---|---|
| Syntrophobacter fumaroxidans | NCBITaxon:119484 |
PRIMARY_DEGRADER
SYNTROPHIC_PARTNER
|
N/A |
| Methanobacterium formicicum | NCBITaxon:2162 |
SYNTROPHIC_PARTNER
|
N/A |
Ecological Interactions
Propionate Oxidation and H2/Formate Production
SYNTROPHYSource Taxon: Syntrophobacter fumaroxidans
Metabolites: propionate (CHEBI:17272), acetate (CHEBI:30089), dihydrogen (CHEBI:18276), formate (CHEBI:15740)
Biological Processes:
- propionate metabolic process (GO:0019541)
- propionate catabolic process (GO:0019543)
Evidence
-
doi:10.1099/00207713-48-4-1383 - SUPPORT (IN_VITRO)"It oxidized propionate syntrophically in co-culture with the hydrogen- and formate-utilizing Methanospirillum hungateii, and was able to oxidize propionate and other organic compounds in pure culture with sulfate or fumarate as the electron acceptor"
-
PMID:29611893 - SUPPORT (IN_VITRO)"Formate dehydrogenase Fdh1 and hydrogenase Hox were the main confurcating enzymes used for energy conservation"
Interspecies Electron Transfer and Methanogenesis
SYNTROPHYSource Taxon: Methanobacterium formicicum
Metabolites: dihydrogen (CHEBI:18276), formate (CHEBI:15740), methane (CHEBI:16183)
Biological Processes:
- methanogenesis (GO:0015948)
Evidence
-
doi:10.1099/00207713-48-4-1383 - SUPPORT (IN_VITRO)"It oxidized propionate syntrophically in co-culture with the hydrogen- and formate-utilizing Methanospirillum hungateii, and was able to oxidize propionate and other organic compounds in pure culture with sulfate or fumarate as the electron acceptor"
-
PMID:29611893 - SUPPORT (IN_VITRO)"fumaroxidans mainly used formate for electron release and that different confurcating mechanisms were used in its sulfidogenic metabolism"
Environmental Factors
| Factor | Value | Unit |
|---|---|---|
| Anaerobic Conditions | Strict anaerobic | N/A |
| Hydrogen and Formate Partial Pressure | Must be maintained at low levels | N/A |
| Ecological Relevance | Biogeochemical cycling | N/A |