identifier: METPO:1000472 label: NaCl range high definition: A NaCl range phenotype in which the growth-supporting NaCl range extends above approximately 8% (w/v), characteristic of extreme-halophile organisms. definition_source: DOI:10.1093/femsre/fuy009 trait_category: ENVIRONMENT term_kind: CLASS mapping_status: REVIEWED parent_traits: - METPO:1000334 synonyms: - synonym_text: Extreme halophile synonym_type: EXACT_SYNONYM source: metpo.owl - synonym_text: NaR_>8 synonym_type: RELATED_SYNONYM source: metpo.owl evidence: - reference: DOI:10.1093/femsre/fuy009 snippet: extreme halophile notes: Osmoadaptation review supports growth ranges extending above 8% NaCl as the extreme-halophile category. - reference: DOI:10.1186/1746-1448-4-2 snippet: KCl accumulating Halobacterium salinarum notes: Saline-Systems review supports salt-in physiology underlying extended high-salt growth. causal_graphs: - graph_id: nacl_range_high_extreme_halophile title: NaCl-range-high extreme-halophile range description: DOI-backed graph linking salt-in physiology to NaCl growth ranges extending above 8% (w/v). nodes: - node_id: nacl_range_high_trait label: NaCl range high node_type: TRAIT grounding: METPO:1000472 description: NaCl growth-supporting range extending above ~8% w/v. - node_id: nacl_range label: NaCl range node_type: TRAIT grounding: METPO:1000334 description: Span of NaCl concentrations supporting growth. - node_id: salt_in_physiology label: salt-in physiology node_type: BIOLOGICAL_PROCESS description: Intracellular ion-accumulation strategy enabling growth at hypersaline NaCl. - node_id: high_external_nacl label: high external NaCl / hypersaline brine node_type: ENVIRONMENTAL_FACTOR description: High extracellular NaCl concentration characteristic of hypersaline brines. - node_id: intracellular_potassium label: intracellular K+ node_type: CHEMICAL description: High intracellular potassium(1+) accumulated by the salt-in strategy. - node_id: acidic_proteome label: acidic proteome node_type: QUALITY description: Proteome enriched in acidic amino acids (Glu/Asp) giving negatively charged surfaces. - node_id: acidic_amino_acid_enrichment label: acidic amino acid enrichment (Asp/Glu) node_type: BIOLOGICAL_PROCESS description: Enrichment of aspartate and glutamate residues in intracellular proteins. - node_id: protein_function_high_ionic label: protein function at very high ionic strength node_type: MOLECULAR_FUNCTION description: Maintenance of protein functionality under molar intracellular ionic strength. - node_id: compatible_solutes label: intracellular compatible solutes node_type: CHEMICAL description: Organic osmolytes accumulated intracellularly to balance osmotic stress. - node_id: protein_stabilization label: protein stabilization under salt stress node_type: BIOLOGICAL_PROCESS description: Stabilization of proteins/enzymes under salt/osmotic stress. edges: - subject: salt_in_physiology predicate: produces object: nacl_range_high_trait description: Salt-in physiology yields a growth range extending above 8% NaCl. evidence: - reference: DOI:10.1186/1746-1448-4-2 snippet: KCl accumulating Halobacterium salinarum notes: Supports salt-in physiology as the basis of extreme-halophile growth ranges. predicate_id: METPO:2000202 - subject: nacl_range_high_trait predicate: is a object: nacl_range description: NaCl range high is a quantitative bin of the NaCl-range phenotype. evidence: - reference: DOI:10.1093/femsre/fuy009 snippet: salinity range notes: Supports the >8% range as a value within the NaCl-range distribution. predicate_id: rdfs:subClassOf - subject: high_external_nacl predicate: induces object: intracellular_potassium description: High external NaCl induces molar intracellular K+ accumulation (salt-in strategy). evidence: - reference: DOI:10.1038/s41559-024-02505-6 notes: Canonical salt-in strategy accumulates molar cytoplasmic K+ (up to 4M) in hypersaline systems. - subject: salt_in_physiology predicate: results in object: acidic_proteome description: Salt-in physiology drives proteome acidification via enrichment in acidic amino acids. evidence: - reference: DOI:10.1038/s41559-024-02505-6 notes: K+ accumulation accompanied by proteome acidification through Glu/Asp enrichment. - subject: acidic_amino_acid_enrichment predicate: contributes to object: protein_function_high_ionic description: Asp/Glu enrichment produces negatively charged surfaces enabling protein function at high ionic strength. evidence: - reference: DOI:10.1093/femsre/fuy026 notes: Salt-in proteins more hydrophilic and enriched in acidic residues, enabling functionality at very high ionic strength. predicate_id: RO:0002326 - subject: salt_in_physiology predicate: depends on object: intracellular_potassium description: Salt-in extreme-halophile physiology depends on high intracellular K+ (proteins misfold below ~2.2 M). evidence: - reference: DOI:10.1093/femsre/fuy026 notes: Cellular vitality of salt-in organisms dependent on high intracellular K+; proteins misfold when K+ falls below ~2.2 M. predicate_id: RO:0002502 - subject: compatible_solutes predicate: stabilizes object: protein_stabilization description: Intracellular compatible solutes stabilize proteins/enzymes under salt stress. evidence: - reference: DOI:10.1007/978-3-030-18975-4_4 notes: Osmolytes act as protein stabilizers/chaperones under salt stress. curation_history: - timestamp: '2026-05-05T01:35:46.837512+00:00' curator: seed_from_metpo action: SEEDED_FROM_METPO changes: imported from data/raw/metpo.owl (CLASS) llm_assisted: false - timestamp: '2026-05-12T10:00:00-07:00' curator: claude action: CURATED_CAUSAL_GRAPH changes: Added DOI-backed definition and causal graph linking salt-in physiology to the extreme-halophile NaCl-range bin. llm_assisted: true - timestamp: '2026-05-20T03:35:30Z' curator: claude action: GROUND_CAUSAL_PREDICATES changes: Grounded 2 causal-edge predicate_id field(s) via mappings/predicate_grounding.tsv (METPO:2000202×1, rdfs:subClassOf×1). llm_assisted: true - timestamp: '2026-06-23T00:00:00Z' curator: claude action: ENRICH_CAUSAL_GRAPH changes: Added 5 evidence-backed generic edges (7 new nodes) from the deep-research report. llm_assisted: true - timestamp: '2026-06-24T17:21:10Z' curator: claude action: GROUND_CAUSAL_PREDICATES changes: Grounded 2 causal-edge predicate_id field(s) via mappings/predicate_grounding.tsv (RO:0002326×1, RO:0002502×1). llm_assisted: true