TraitMech

TraitMech › ENVIRONMENT

mercury tolerant

traitmech:000016 · CLASS · REVIEWED

A metal tolerance in which an organism grows in the presence of toxic inorganic or organic mercury compounds, typically via the mer operon, whose mercuric reductase (MerA) reduces reactive Hg(II) to volatile Hg(0).

Mercury tolerance via mer-operon MerA reductase

Evidence-backed causal sketch linking mer-operon mercuric reductase to volatilization of Hg(II) into Hg(0).

Mercury tolerance via mer-operon MerA reductase Interactive directed graph showing evidence-backed causal relationships for mercury tolerant.

Edge evidence

  • mercury(2+) ion challenges mercury tolerant METPO:2007406

    Reactive Hg(II) is the toxic challenge the trait counters.

    • PMID:12829273 Mercury detoxification sits within the broader prokaryotic metal-resistance machinery.
  • mer operon (MerA reductase) enables mercury(II) reduction RO:0002327

    MerA reduces Hg(II) to volatile, inert Hg(0) vapour.

    • DOI:10.1016/S0168-6445(03)00046-9 MerA reduces reactive ionic Hg(II) to volatile, relatively inert, monoatomic Hg(0) vapor.
  • mercury(II) reduction mitigates mercury(2+) ion METPO:2007407

    Reduction to Hg(0) depletes the reactive Hg(II) pool.

    • DOI:10.1016/S0168-6445(03)00046-9 Mercury reduction is the basis of mer-mediated resistance.
  • mer operon (MerA reductase) produces mercury(0) METPO:2000202

    MerA reduction of Hg(II) yields volatile elemental Hg(0).

    • DOI:10.1186/s12866-024-03391-5 MerA reduces Hg2+ to volatile Hg0, relieving intracellular Hg(II) toxicity.
  • MerB (organomercurial lyase) cleaves organomercurial compound

    MerB lyase cleaves C-Hg bonds of organomercurials to release Hg(II) for MerA reduction.

    • DOI:10.21203/rs.3.rs-3854515/v1 MerB is an organomercury lyase that cleaves methylmercury to Hg2+ and methane.
  • MerB (organomercurial lyase) produces mercury(2+) ion METPO:2000202

    Organomercurial cleavage yields Hg(II), the substrate for MerA reduction.

    • DOI:10.21203/rs.3.rs-3854515/v1 C-Hg bond cleavage produces Hg(II) for subsequent MerA reduction.
  • MerR (Hg-responsive regulator) senses mercury(2+) ion

    MerR senses Hg(II), acting as a mercury-responsive transcriptional regulator.

    • DOI:10.21203/rs.3.rs-3854515/v1 MerR functions as a repressor/activator responsive to Hg2+.
  • MerR (Hg-responsive regulator) activates mer operon transcription RO:0002213

    Hg(II)-bound MerR activates transcription of the mer detoxification genes from Pmer.

    • DOI:10.3389/fbioe.2023.1178680 MerR-mediated activation of Pmer drives mer operon transcription when Hg(II) is present.

Provenance

Source
METPO (2025-11-25)
Definition source
DOI:10.1016/S0168-6445(03)00046-9

Parent traits (1)

Synonyms (1)

  • mercury resistant RELATED_SYNONYM · DOI:10.1016/S0168-6445(03)00046-9

kg-microbe context

Matched 1 kg-microbe node via parent_proxy.

  • METPO:1000059 [-2.682, -2.070, -3.656, -0.652, …]

512-dim DeepWalkSkipGramEnsmallen embedding from kg-microbe (2026-04-25).

Nearest neighbors in embedding space

Top-8 cosine-similar METPO traits from the 2026-04-25 deepwalk (512-D).

Curation history

  1. · PROPOSED_FROM_RESEARCH · claude

    Proposed candidate ENVIRONMENT trait (mercury tolerance) from literature research; metal-specific sub-variant of metal tolerant.

  2. · CURATED_CAUSAL_GRAPH · claude

    Added evidence-backed causal graph (mer-operon Hg(II) reduction) with CHEBI node grounding and RO/METPO predicate groundings; promoted PROPOSED to REVIEWED.

  3. · ENRICH_CAUSAL_GRAPH · claude

    Added 5 evidence-backed generic edges (5 new nodes) from the deep-research report.

  4. · GROUND_CAUSAL_PREDICATES · claude

    Grounded 3 causal-edge predicate_id field(s) via mappings/predicate_grounding.tsv (METPO:2000202×2, RO:0002213×1).

  5. · GROUND_CAUSAL_NODES · claude

    Grounded 1 causal-node grounding field(s) via mappings/node_grounding.tsv (CHEBI:16170×1).