identifier: traitmech:000105
label: dissimilatory sulfate reduction
definition: An anaerobic respiratory metabolism in which an organism uses sulfate
  as the terminal electron acceptor, reducing it to hydrogen sulfide while oxidizing
  organic matter or hydrogen for energy.
definition_source: DOI:10.1038/nrmicro1892
trait_category: METABOLISM
term_kind: CLASS
mapping_status: REVIEWED
parent_traits:
- METPO:1000802
synonyms:
- synonym_text: sulfate respiration
  synonym_type: RELATED_SYNONYM
  source: DOI:10.1038/nrmicro1892
evidence:
- reference: DOI:10.1038/nrmicro1892
  notes: Muyzer & Stams review sulfate-reducing bacteria, which respire sulfate to
    sulfide in anoxic habitats.
- reference: DOI:10.3389/fmicb.2011.00081
  notes: Plugge et al. review the metabolic flexibility of sulfate-reducing bacteria.
canonical_examples:
- taxon_id: NCBITaxon:882
  taxon_label: Nitratidesulfovibrio vulgaris str. Hildenborough
  note: "Model dissimilatory sulfate reducer (formerly Desulfovibrio vulgaris Hildenborough)."
  reference: PMID:15077118
causal_graphs:
- graph_id: sulfate_reduction_to_sulfide
  title: Dissimilatory sulfate reduction respires sulfate to sulfide
  description: Evidence-backed causal sketch linking sulfate as terminal electron
    acceptor to sulfide production in anoxic anaerobic respiration.
  nodes:
  - node_id: sulfate_reduction_trait
    label: dissimilatory sulfate reduction
    node_type: TRAIT
    grounding: traitmech:000105
    description: Anaerobic respiration on sulfate as terminal electron acceptor.
  - node_id: sulfate
    label: sulfate
    node_type: CHEMICAL
    grounding: CHEBI:16189
    description: Terminal electron acceptor reduced in this respiration.
  - node_id: sulfide
    label: sulfide
    node_type: CHEMICAL
    grounding: CHEBI:15138
    description: Final reduction product released to anoxic habitats.
  - node_id: anaerobic_respiration
    label: anaerobic respiration
    node_type: BIOLOGICAL_PROCESS
    grounding: GO:0009061
    description: Energy-conserving respiration with non-O2 acceptor.
  - node_id: sat_enzyme
    label: ATP sulfurylase (Sat)
    node_type: GENE_OR_PROTEIN
    description: Sulfate adenylyltransferase that activates sulfate to APS.
  - node_id: aps
    label: adenosine-5′-phosphosulfate (APS)
    node_type: CHEMICAL
    description: Activated sulfate intermediate reduced to sulfite.
  - node_id: sulfite
    label: sulfite
    node_type: CHEMICAL
    description: Intermediate produced from APS, substrate of the Dsr cascade.
  - node_id: aprab_complex
    label: APS reductase AprAB
    node_type: GENE_OR_PROTEIN
    description: Reduces APS to sulfite.
  - node_id: dsrab_dsrc
    label: DsrAB with DsrC
    node_type: GENE_OR_PROTEIN
    description: Dissimilatory sulfite reductase DsrAB acting with DsrC protein.
  - node_id: dsrc_trisulfide
    label: DsrC-trisulfide
    node_type: CHEMICAL
    description: Protein-bound trisulfide intermediate from sulfite reduction.
  - node_id: dsrmkjop_complex
    label: DsrMK(JOP) membrane complex
    node_type: GENE_OR_PROTEIN
    description: Reduces DsrC-trisulfide to sulfide, recycling DsrC and conserving
      energy.
  - node_id: srm
    label: sulfate/sulfite-reducing microorganisms
    node_type: STATE
    description: Microorganisms capable of dissimilatory sulfate/sulfite reduction.
  edges:
  - subject: sulfate
    predicate: oxidized to
    object: sulfide
    description: Sulfate is reduced stepwise to sulfide.
    evidence:
    - reference: DOI:10.1038/nrmicro1892
      notes: Muyzer & Stams review sulfate-reducing bacteria respiring sulfate to
        sulfide.
    predicate_id: METPO:2007405
  - subject: sulfate_reduction_trait
    predicate: participates in
    object: anaerobic_respiration
    description: Sulfate respiration is a major form of anaerobic respiration.
    evidence:
    - reference: DOI:10.3389/fmicb.2011.00081
      notes: Plugge et al. review the metabolic flexibility of sulfate-reducing bacteria
        within anaerobic respiration.
    predicate_id: biolink:participates_in
  - subject: sulfate
    predicate: activated by
    object: sat_enzyme
    description: Sulfate is activated by ATP sulfurylase (Sat).
    evidence:
    - reference: DOI:10.3390/antiox12030767
      notes: Sulfate is taken up and activated by the enzyme ATP sulfurylase (Sat)
        to form APS.
  - subject: sat_enzyme
    predicate: produces
    object: aps
    description: Sat activates sulfate to form APS.
    evidence:
    - reference: DOI:10.3390/antiox12030767
      notes: Activated by ATP sulfurylase (Sat) to form adenosine-5′-phosphosulfate
        (APS).
    predicate_id: METPO:2000202
  - subject: aprab_complex
    predicate: reduces
    object: aps
    description: APS reductase AprAB reduces APS to sulfite.
    evidence:
    - reference: DOI:10.1038/s41396-023-01477-y
      notes: The APS reductase AprAB reduces APS to sulfite, serving as substrate
        of the Dsr cascade.
    predicate_id: METPO:2000017
  - subject: aprab_complex
    predicate: produces
    object: sulfite
    description: AprAB reduction of APS yields sulfite.
    evidence:
    - reference: DOI:10.1038/s41396-023-01477-y
      notes: APS is reduced to sulfite serving as substrate of the Dsr cascade.
    predicate_id: METPO:2000202
  - subject: dsrab_dsrc
    predicate: produces
    object: dsrc_trisulfide
    description: DsrAB produces a DsrC-trisulfide from sulfite and DsrC.
    evidence:
    - reference: DOI:10.1038/s41396-023-01477-y
      notes: DsrAB produces a DsrC-trisulfide from sulfite and the DsrC protein.
    predicate_id: METPO:2000202
  - subject: dsrmkjop_complex
    predicate: reduces
    object: dsrc_trisulfide
    description: DsrMK(JOP) reduces the DsrC-trisulfide, recycling DsrC and releasing
      sulfide with energy conservation.
    evidence:
    - reference: DOI:10.1038/s41396-023-01477-y
      notes: DsrC-trisulfide is reduced by the DsrMK(JOP) membrane complex recycling
        DsrC and releasing sulfide while coupling to energy conservation.
    predicate_id: METPO:2000017
  - subject: dsrmkjop_complex
    predicate: produces
    object: sulfide
    description: Terminal reduction of the DsrC-trisulfide releases sulfide.
    evidence:
    - reference: DOI:10.1038/s41396-023-01477-y
      notes: DsrMK(JOP) reduction releases sulfide while coupling this reduction to
        energy conservation.
    predicate_id: METPO:2000202
  - subject: dsrab_dsrc
    predicate: marker for
    object: srm
    description: The dissimilatory sulfite reductase encoded by dsrAB is a hallmark
      of sulfate/sulfite-reducing microorganisms.
    evidence:
    - reference: DOI:10.1093/femsre/fuad058
      notes: A hallmark of SRM is the dissimilatory sulfite reductase encoded by the
        genes dsrAB.
curation_history:
- timestamp: '2026-06-08T00:00:00Z'
  curator: claude
  action: PROPOSED_FROM_RESEARCH
  changes: Proposed candidate METABOLISM trait (dissimilatory sulfate reduction);
    round 2, parented to anaerobic respiration (METPO:1000802).
  llm_assisted: true
- timestamp: '2026-06-10T14:00:00Z'
  curator: claude
  action: CURATED_CAUSAL_GRAPH
  changes: Added evidence-backed causal graph (sulfate → sulfide respiration) with
    CHEBI/GO node groundings and METPO/biolink predicate groundings; promoted PROPOSED
    to REVIEWED.
  llm_assisted: true
- timestamp: '2026-06-23T00:00:00Z'
  curator: claude
  action: ENRICH_CAUSAL_GRAPH
  changes: Added 8 evidence-backed generic edges (8 new nodes) from the deep-research
    report.
  llm_assisted: true
- timestamp: '2026-06-24T17:21:12Z'
  curator: claude
  action: GROUND_CAUSAL_PREDICATES
  changes: Grounded 6 causal-edge predicate_id field(s) via mappings/predicate_grounding.tsv
    (METPO:2000202×4, METPO:2000017×2).
  llm_assisted: true