identifier: METPO:1000624 label: non halophilic definition: A halophily preference in which an organism does not require or prefer elevated salt concentrations for growth. definition_source: DOI:10.1128/AEM.01934-12 trait_category: ENVIRONMENT term_kind: CLASS mapping_status: REVIEWED parent_traits: - METPO:1000629 synonyms: - synonym_text: non-halophilic synonym_type: RELATED_SYNONYM source: metpo.owl evidence: - reference: DOI:10.1128/AEM.01934-12 snippet: B. subtilis can attain cellular protection notes: Supports salt-stress protection mechanisms in a non-halophilic bacterial model. - reference: PMID:11583854 snippet: Vibrio cholerae non-O1, a non-halophilic bacterium notes: 'Organism example: Vibrio cholerae non-O1 is described as non-halophilic.' canonical_examples: - taxon_id: NCBITaxon:562 taxon_label: Escherichia coli note: "grows without added NaCl" reference: PMC8415458 - taxon_id: NCBITaxon:1423 taxon_label: Bacillus subtilis note: "non-halophilic soil bacterium" reference: PMID:9384377 causal_graphs: - graph_id: non_halophilic_salt_stress_response title: Non-halophilic salt-stress response mechanism description: Evidence-backed causal sketch linking non-halophily to lack of salt requirement, high-osmolarity stress, potassium uptake, and compatible-solute protection. nodes: - node_id: non_halophilic_trait label: non halophilic node_type: TRAIT grounding: METPO:1000624 description: Growth does not require or prefer elevated salt concentration. - node_id: low_to_moderate_salinity label: low-to-moderate salinity node_type: ENVIRONMENTAL_FACTOR description: Non-elevated salinity condition compatible with non-halophilic growth. - node_id: high_osmolarity label: high osmolarity node_type: ENVIRONMENTAL_FACTOR description: Hyperosmotic condition that can inhibit growth of non-halophiles. grounding: PATO:0001657 - node_id: water_flux label: water flux across cytoplasmic membrane node_type: BIOLOGICAL_PROCESS description: Osmotically driven water movement during osmotic upshift or downshift. - node_id: potassium_ion label: potassium ion node_type: CHEMICAL grounding: CHEBI:29103 description: Ion accumulated as an early osmotic-stress response. - node_id: proline label: proline node_type: CHEMICAL grounding: CHEBI:17203 description: Compatible solute synthesized by Bacillus subtilis during osmotic adaptation. - node_id: compatible_solute_uptake label: compatible-solute uptake systems node_type: GENE_OR_PROTEIN description: Transporters importing glycine betaine, proline, ectoine, or other osmoprotectants. - node_id: osmotic_upshift label: osmotic upshift node_type: ENVIRONMENTAL_FACTOR description: Hypertonic/NaCl upshift imposing increased external osmolarity. - node_id: water_efflux_volume_decrease label: water efflux and cytoplasmic volume decrease node_type: BIOLOGICAL_PROCESS description: Rapid loss of water and drop in cytoplasmic volume/turgor after hypertonic stress. - node_id: rapid_k_uptake label: rapid potassium uptake node_type: BIOLOGICAL_PROCESS description: Emergency K+ import as the primary early osmotic-upshift response. - node_id: glutamate label: L-glutamate node_type: CHEMICAL description: Counterion accumulated/synthesized to balance K+ and maintain electroneutrality. - node_id: compatible_solute_accumulation label: compatible solute accumulation node_type: BIOLOGICAL_PROCESS description: Accumulation/synthesis of neutral compatible solutes replacing K+ as a secondary osmoadaptive response. edges: - subject: low_to_moderate_salinity predicate: enables object: non_halophilic_trait description: Non-halophilic organisms do not require elevated salinity for growth. evidence: - reference: DOI:10.1128/AEM.01934-12 snippet: soil-dwelling bacterium Bacillus subtilis notes: Bacillus subtilis is used here as a non-halophilic model for salt stress responses rather than salt-requiring growth. predicate_id: RO:0002327 - subject: high_osmolarity predicate: regulates object: water_flux description: Hyperosmotic stress alters cellular water balance and can impair non-halophilic growth. evidence: - reference: DOI:10.1128/AEM.01934-12 snippet: outflow of water, drop in turgor, and the ensuing growth arrest notes: Supports high-osmolarity growth inhibition through water loss and turgor decrease. predicate_id: RO:0002211 - subject: potassium_ion predicate: mitigates object: water_flux description: Rapid potassium accumulation helps adjust cytoplasmic osmotic potential after osmotic upshift. evidence: - reference: DOI:10.1128/AEM.01934-12 snippet: initially importing substantial amounts of potassium ions notes: Supports potassium uptake as an initial osmotic response. predicate_id: METPO:2007407 - subject: proline predicate: mitigates object: water_flux description: Proline accumulation supports osmoadaptation under sustained high-osmolarity conditions. evidence: - reference: DOI:10.1128/JB.00778-11 snippet: proline production is required notes: Supports de novo proline synthesis in Bacillus subtilis osmotic defense. predicate_id: METPO:2007407 - subject: compatible_solute_uptake predicate: imports object: proline description: Uptake systems can import osmoprotectants that relieve high osmolarity. evidence: - reference: DOI:10.1128/AEM.01934-12 snippet: osmotically controlled uptake systems notes: Supports uptake systems for compatible solutes in Bacillus subtilis. predicate_id: METPO:2000208 - subject: proline predicate: enables tolerance of object: high_osmolarity description: Proline acts as an osmoprotectant enabling survival or growth under salt stress without making salt a growth requirement. evidence: - reference: DOI:10.1128/AEM.01934-12 snippet: proline as an osmoprotectant notes: Supports proline-mediated protection in a non-halophilic bacterial model. - subject: osmotic_upshift predicate: causes object: water_efflux_volume_decrease description: Hypertonic stress drives rapid water efflux and cytoplasmic volume/turgor decrease. evidence: - reference: DOI:10.1128/mmbr.00181-23 notes: Under hypertonic stress water exits cells within milliseconds, causing cytoplasmic volume decreases up to ~50%, a rapid fall in turgor and increased ionic strength. predicate_id: biolink:causes - subject: osmotic_upshift predicate: induces object: rapid_k_uptake description: Cells import large amounts of K+ as the primary emergency response to osmotic upshift. evidence: - reference: DOI:10.1128/mmbr.00181-23 notes: Cells commonly import large amounts of K+ during osmotic upshift; generic across non-halophilic bacteria. - subject: rapid_k_uptake predicate: requires counterion balancing by object: glutamate description: Glutamate is imported or synthesized as the counterion to balance accumulated K+ and maintain electroneutrality. evidence: - reference: DOI:10.1128/mmbr.00181-23 notes: Glutamate commonly imported or synthesized as the counterion to maintain electroneutrality during K+ accumulation. - subject: rapid_k_uptake predicate: promotes replacement by object: compatible_solute_accumulation description: High intracellular K+/ionic strength is mitigated by secondary accumulation of neutral compatible solutes that replace K+. evidence: - reference: DOI:10.1128/mmbr.00181-23 notes: Bacteria such as E. coli and B. subtilis accumulate/synthesize neutral compatible solutes to replace K+; compatible-solute accumulation is a secondary response following primary K+ accumulation. curation_history: - timestamp: '2026-05-05T01:35:46.863044+00:00' curator: seed_from_metpo action: SEEDED_FROM_METPO changes: imported from data/raw/metpo.owl (CLASS) llm_assisted: false - timestamp: '2026-05-06T14:15:44-07:00' curator: codex action: CURATED_WITH_ORGANISM_EXAMPLE changes: Added Vibrio cholerae non-O1 organism example with PMID-backed evidence. llm_assisted: true - timestamp: '2026-05-11T00:00:00-07:00' curator: codex action: CURATED_WITH_LITERATURE changes: Added DOI-backed non-halophilic causal graph for salt-stress response in a non-halophilic Bacillus model, including K+ uptake, proline, and compatible-solute uptake systems. llm_assisted: true - timestamp: '2026-05-23T21:30:06Z' curator: claude action: GROUND_CAUSAL_PREDICATES changes: Grounded 2 causal-edge predicate_id field(s) via mappings/predicate_grounding.tsv (METPO:2007407×2). llm_assisted: true - timestamp: '2026-05-24T04:13:18Z' curator: claude action: RENAME_PREDICATE_LABELS changes: 'Renamed 2 causal-edge predicate label(s) to align with existing groundings: supports → enables ×1; drives → regulates ×1.' llm_assisted: true - timestamp: '2026-05-24T04:13:21Z' curator: claude action: GROUND_CAUSAL_PREDICATES changes: Grounded 2 causal-edge predicate_id field(s) via mappings/predicate_grounding.tsv (RO:0002327×1, RO:0002211×1). llm_assisted: true - timestamp: '2026-06-14T05:51:45Z' curator: claude action: GROUND_CAUSAL_NODES changes: Grounded 1 causal-node grounding field(s) via mappings/node_grounding.tsv (PATO:0001657×1). llm_assisted: true - timestamp: '2026-06-16T06:30:55Z' curator: claude action: GROUND_CAUSAL_PREDICATES changes: Grounded 1 causal-edge predicate_id field(s) via mappings/predicate_grounding.tsv (METPO:2000208×1). llm_assisted: true - timestamp: '2026-06-23T00:00:00Z' curator: claude action: ENRICH_CAUSAL_GRAPH changes: Added 4 evidence-backed generic edges (5 new nodes) from the deep-research report. llm_assisted: true - timestamp: '2026-06-24T17:21:10Z' curator: claude action: GROUND_CAUSAL_PREDICATES changes: Grounded 1 causal-edge predicate_id field(s) via mappings/predicate_grounding.tsv (biolink:causes×1). llm_assisted: true