identifier: METPO:1000451 label: temperature range mid2 definition: A temperature range phenotype in which the growth-supporting ambient temperature range spans approximately 27–30 °C, characteristic of mesophilic physiology. definition_source: DOI:10.1146/annurev-micro-091313-103612 trait_category: ENVIRONMENT term_kind: CLASS mapping_status: REVIEWED parent_traits: - METPO:1000306 synonyms: - synonym_text: Mesophilie synonym_type: EXACT_SYNONYM source: metpo.owl - synonym_text: TR_27_to_30 synonym_type: RELATED_SYNONYM source: metpo.owl evidence: - reference: DOI:10.1146/annurev-micro-091313-103612 snippet: more unsaturated fatty acids notes: Membrane-adaptation review supports the 27–30 °C range as a typical mesophile growth range. causal_graphs: - graph_id: temperature_range_mid2_baseline_mesophile title: Temperature-range-mid2 baseline-mesophile range description: DOI-backed graph linking baseline mesophile adaptation to a temperature growth range of approximately 27–30 °C. nodes: - node_id: temperature_range_mid2_trait label: temperature range mid2 node_type: TRAIT grounding: METPO:1000451 description: Temperature growth-supporting range approximately 27–30 °C. - node_id: temperature_range label: temperature range node_type: TRAIT grounding: METPO:1000306 description: Span of ambient temperatures supporting growth. - node_id: baseline_mesophile_adaptation label: baseline mesophile adaptation node_type: BIOLOGICAL_PROCESS description: Standard mesophile membrane and enzyme repertoire supporting growth at moderate ambient temperatures. - node_id: homeoviscous_adaptation label: homeoviscous adaptation node_type: BIOLOGICAL_PROCESS description: Regulation of membrane lipid composition to maintain constant viscosity/fluidity across temperatures. - node_id: membrane_fluidity label: membrane fluidity node_type: QUALITY description: Fluid state of the lipid bilayer required for membrane function. grounding: METPO:1007505 - node_id: unsaturated_fatty_acid_fraction label: unsaturated fatty acid fraction node_type: CHEMICAL description: Proportion of unsaturated fatty acids in membrane phospholipids. - node_id: hopanoids_sterol_like label: hopanoids / sterol-like molecules node_type: CHEMICAL description: Membrane-embedded sterol-like regulators of bilayer fluidity. - node_id: elevated_temperature label: elevated temperature node_type: ENVIRONMENTAL_FACTOR description: Increase in ambient growth temperature. - node_id: rna_thermometer label: RNA thermometer 5′-UTR structure node_type: GENE_OR_PROTEIN description: Temperature-responsive mRNA 5′-UTR secondary structure controlling translation initiation. - node_id: temperature_shift label: temperature shift / heat shock node_type: ENVIRONMENTAL_FACTOR description: Abrupt change in ambient temperature, including heat shock. - node_id: heat_shock_proteins label: heat-shock proteins / chaperones node_type: GENE_OR_PROTEIN description: Molecular chaperones induced by thermal stress that maintain proteostasis. - node_id: protein_denaturation label: protein denaturation / aggregation node_type: BIOLOGICAL_PROCESS description: Loss of protein structure and aggregation under thermal stress. - node_id: mesophilic_organisms label: mesophilic organisms node_type: STATE description: Organisms growing at moderate temperatures (~20-45 °C). edges: - subject: baseline_mesophile_adaptation predicate: enables object: temperature_range_mid2_trait description: Baseline mesophile adaptation enables growth across 27–30 °C. evidence: - reference: DOI:10.1146/annurev-micro-091313-103612 snippet: more unsaturated fatty acids notes: Supports baseline mesophile homeoviscous adaptation as the range mechanism. predicate_id: RO:0002327 - subject: temperature_range_mid2_trait predicate: is a object: temperature_range description: Temperature range mid2 is a quantitative bin of the temperature-range phenotype. evidence: - reference: DOI:10.1016/s0300-9629(97)00003-0 snippet: adapted to environments of high temperature notes: Supports the 27–30 °C range as a value within the temperature-range distribution. predicate_id: rdfs:subClassOf - subject: homeoviscous_adaptation predicate: maintains object: membrane_fluidity description: Homeoviscous adaptation maintains membrane lipid viscosity/fluidity. evidence: - reference: DOI:10.1007/s42770-023-01057-4 notes: Homeoviscous adaptation regulates membrane lipid viscosity; generic background mechanism for mesophilic temperature tolerance. - subject: unsaturated_fatty_acid_fraction predicate: increases object: membrane_fluidity description: Increased unsaturated fatty acid fraction increases membrane fluidity. evidence: - reference: DOI:10.1007/s12275-023-00031-x notes: Higher unsaturated content increases fluidity; canonical general bacterial thermoadaptation mechanism. predicate_id: RO:0002213 - subject: hopanoids_sterol_like predicate: regulates object: membrane_fluidity description: Hopanoids / sterol-like molecules regulate membrane fluidity. evidence: - reference: DOI:10.1007/s42770-023-01057-4 notes: Hopanoids and sterol-like molecules act as regulators of membrane fluidity; broad membrane-modulator edge. predicate_id: RO:0002211 - subject: membrane_fluidity predicate: enables object: temperature_range_mid2_trait description: Maintained membrane fluidity enables growth across the mid2 temperature range. evidence: - reference: DOI:10.1146/annurev-micro-091313-103612 notes: Functional membrane fluidity underlies homeoviscous adaptation supporting the mesophile range. predicate_id: RO:0002327 - subject: elevated_temperature predicate: opens object: rna_thermometer description: Elevated temperature melts/opens RNA thermometer 5′-UTR secondary structure. evidence: - reference: DOI:10.1007/s12551-025-01290-1 notes: 5′-UTR secondary structures melt upon heat exposure, exposing ribosome binding sites; broad review-level support. - subject: temperature_shift predicate: induces object: heat_shock_proteins description: Temperature shift / heat shock induces heat-shock proteins and chaperones. evidence: - reference: DOI:10.1007/s12275-023-00031-x notes: Temperature shifts induce heat- and cold-shock proteins; high-confidence general stress-response edge. - subject: heat_shock_proteins predicate: counteracts object: protein_denaturation description: Heat-shock proteins / chaperones counteract protein denaturation and aggregation. evidence: - reference: DOI:10.1007/s12275-023-00031-x notes: Chaperones counteract denaturation and aid tolerance; strong general proteostasis edge. - subject: baseline_mesophile_adaptation predicate: characterizes object: mesophilic_organisms description: Mesophilic organisms grow between ~20 °C and ~45 °C, bracketing the mid2 range. evidence: - reference: DOI:10.1007/s42770-023-01057-4 notes: Mesophiles grow between room temperature (~20 °C) and ~45 °C; scope-defining edge placing 27-30 °C within mesophily. curation_history: - timestamp: '2026-05-05T01:35:46.824255+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 baseline mesophile adaptation to the temperature-range-mid2 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 8 evidence-backed generic edges (10 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:0002213×1, RO:0002211×1, RO:0002327×1). llm_assisted: true - timestamp: '2026-06-24T17:21:18Z' curator: claude action: GROUND_CAUSAL_NODES changes: Grounded 1 causal-node grounding field(s) via mappings/node_grounding.tsv (METPO:1007505×1). llm_assisted: true