identifier: METPO:1000448 label: temperature range very low definition: A temperature range phenotype in which growth extends to ambient temperatures at or below approximately 10 °C, characteristic of psychrophilic growth ranges. definition_source: DOI:10.1038/sj.embor.7400662 trait_category: ENVIRONMENT term_kind: CLASS mapping_status: REVIEWED parent_traits: - METPO:1000306 synonyms: - synonym_text: Psychrophile synonym_type: EXACT_SYNONYM source: metpo.owl - synonym_text: TR_<=10 synonym_type: RELATED_SYNONYM source: metpo.owl evidence: - reference: DOI:10.1038/sj.embor.7400662 snippet: growing well at temperatures around the freezing point of water notes: Psychrophile review supports growth at very low temperatures as the psychrophilic range. causal_graphs: - graph_id: temperature_range_very_low_psychrophile title: Temperature-range-very-low psychrophile range description: DOI-backed graph linking psychrophile cold-adapted machinery to a temperature growth range reaching ≤ ~10 °C. nodes: - node_id: temperature_range_very_low_trait label: temperature range very low node_type: TRAIT grounding: METPO:1000448 description: Temperature growth-supporting range reaching ≤ ~10 °C. - node_id: temperature_range label: temperature range node_type: TRAIT grounding: METPO:1000306 description: Span of ambient temperatures supporting growth. - node_id: psychrophile_machinery label: psychrophile cold-adapted machinery node_type: BIOLOGICAL_PROCESS description: Cold-active enzymes and unsaturated-lipid membranes that sustain function near freezing. - node_id: low_temperature label: low temperature node_type: ENVIRONMENTAL_FACTOR description: Ambient temperature at or below ~10 C imposing cold stress. grounding: PATO:0001306 - node_id: membrane_fatty_acid_desaturation label: membrane fatty-acid desaturation node_type: BIOLOGICAL_PROCESS description: Introduction of double bonds into membrane lipids during cold adaptation. - node_id: membrane_fluidity label: membrane fluidity node_type: QUALITY description: Physical fluidity of the membrane bilayer required for function in the cold. grounding: METPO:1007505 - node_id: two_component_cold_signaling label: two-component cold signaling node_type: BIOLOGICAL_PROCESS description: Two-component regulatory systems triggered by cold-induced membrane state changes. - node_id: cold_shock_proteins label: cold-shock proteins (CspA-family) node_type: GENE_OR_PROTEIN description: CspA-family RNA chaperones that bind nucleic acids during cold acclimation. - node_id: rna_secondary_structure label: mRNA/RNA secondary structure node_type: CHEMICAL description: Cold-stabilized RNA secondary structures impeding translation. - node_id: molecular_chaperones label: molecular chaperones (DnaK/GroEL/GroES/Clp/TF) node_type: GENE_OR_PROTEIN description: Chaperone and protease systems maintaining proteostasis under cold. - node_id: proteostasis_cold label: protein folding and proteostasis in the cold node_type: BIOLOGICAL_PROCESS description: Maintenance of correct protein folding despite cold-slowed folding kinetics. - node_id: compatible_solutes label: compatible solutes (glycine betaine/trehalose/glycerol) node_type: CHEMICAL description: Osmolytes that lower freezing damage and stabilize macromolecules. - node_id: protein_membrane_stabilization label: protein and membrane stabilization node_type: BIOLOGICAL_PROCESS description: Stabilization of proteins and membranes against cold/freezing damage. - node_id: ice_binding_proteins label: ice-binding/antifreeze proteins node_type: GENE_OR_PROTEIN description: AFPs/IBPs that bind ice and inhibit ice-crystal growth. - node_id: ice_crystal_growth label: ice-crystal growth/recrystallization node_type: BIOLOGICAL_PROCESS description: Damaging ice-crystal growth and recrystallization around cells. edges: - subject: psychrophile_machinery predicate: enables object: temperature_range_very_low_trait description: Psychrophile cold-adapted machinery enables growth at ≤ 10 °C. evidence: - reference: DOI:10.1038/sj.embor.7400662 snippet: decreased membrane fluidity notes: Supports cold-adapted membranes and enzymes as enablers of growth at very low temperatures. predicate_id: RO:0002327 - subject: temperature_range_very_low_trait predicate: is a object: temperature_range description: Temperature range very low is a quantitative bin of the temperature-range phenotype. evidence: - reference: DOI:10.1038/sj.embor.7400662 snippet: growing well at temperatures around the freezing point of water notes: Supports a ≤10 °C range as a value within the temperature-range distribution. predicate_id: rdfs:subClassOf - subject: membrane_fatty_acid_desaturation predicate: increases object: membrane_fluidity description: Homeoviscous adaptation via lipid desaturation maintains membrane fluidity in the cold. evidence: - reference: DOI:10.1007/s42770-023-01057-4 notes: Cells adapt membrane composition (increasing double bonds in lipids) to maintain fluidity and function. predicate_id: RO:0002213 - subject: low_temperature predicate: activates object: two_component_cold_signaling description: Cold-induced membrane state changes activate two-component cold signaling. evidence: - reference: DOI:10.1007/s42770-023-01057-4 notes: Cold sensing occurs via changes in the liquid-crystalline state of membranes that activate two-component signaling systems. predicate_id: RO:0002213 - subject: cold_shock_proteins predicate: acts on object: rna_secondary_structure description: CspA-family RNA chaperones resolve cold-stabilized RNA structures to sustain translation. evidence: - reference: DOI:10.1007/s42770-023-01057-4 notes: Cold-shock proteins (CSPs) act on mRNAs; increased levels of nucleic-acid-binding CspA-related proteins. - subject: molecular_chaperones predicate: preserves object: proteostasis_cold description: Chaperone/protease systems counter cold-slowed folding and misfolding risk. evidence: - reference: DOI:10.3389/fmicb.2023.1197797 notes: Psychrophiles constitutively synthesize molecular chaperones; Clp/GroEL/DnaK/GroES/TF upregulated during cold shock. - subject: compatible_solutes predicate: stabilizes object: protein_membrane_stabilization description: Osmolytes lower freezing damage and stabilize proteins and membranes. evidence: - reference: DOI:10.3389/fmicb.2023.1197797 notes: Accumulation of compatible osmolytes prevents cell shrinkage, lowers cytoplasmic freezing point, and stabilizes proteins and membranes. - subject: ice_binding_proteins predicate: inhibits object: ice_crystal_growth description: AFPs/IBPs bind ice and inhibit ice-crystal growth and recrystallization. evidence: - reference: DOI:10.3389/fmicb.2023.1197797 notes: AFPs bind ice, inhibit ice-crystal growth, produce thermal hysteresis, and show IRI activity. predicate_id: RO:0002212 curation_history: - timestamp: '2026-05-05T01:35:46.822647+00:00' curator: seed_from_metpo action: SEEDED_FROM_METPO changes: imported from data/raw/metpo.owl (CLASS) llm_assisted: false - timestamp: '2026-05-13T11:00:00-07:00' curator: claude action: CURATED_CAUSAL_GRAPH changes: Added DOI-backed definition and causal graph linking psychrophile cold-adapted machinery to the temperature-range-very-low 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 (RO:0002327×1, rdfs:subClassOf×1). llm_assisted: true - timestamp: '2026-06-23T00:00:00Z' curator: claude action: ENRICH_CAUSAL_GRAPH changes: Added 6 evidence-backed generic edges (12 new nodes) from the deep-research report. llm_assisted: true - timestamp: '2026-06-24T17:21:11Z' curator: claude action: GROUND_CAUSAL_PREDICATES changes: Grounded 3 causal-edge predicate_id field(s) via mappings/predicate_grounding.tsv (RO:0002213×2, RO:0002212×1). llm_assisted: true - timestamp: '2026-06-24T17:21:18Z' curator: claude action: GROUND_CAUSAL_NODES changes: Grounded 2 causal-node grounding field(s) via mappings/node_grounding.tsv (PATO:0001306×1, METPO:1007505×1). llm_assisted: true