identifier: METPO:1000691 label: irregular shaped definition: A cell shape lacking a consistent geometric form across individual cells of a population. definition_source: DOI:10.1146/annurev-cellbio-101011-155745 trait_category: MORPHOLOGY term_kind: CLASS mapping_status: REVIEWED parent_traits: - METPO:1000666 synonyms: - synonym_text: irregular synonym_type: RELATED_SYNONYM source: metpo.owl evidence: - reference: DOI:10.1146/annurev-cellbio-101011-155745 snippet: cell shape is genetically determined notes: Cell-shape review supports loss of cytoskeletal/wall-patterning control as the basis for irregular morphology. - reference: DOI:10.1111/j.1574-6976.2011.00298.x snippet: coryneform morphology notes: Corynebacterineae review supports irregular and coryneform morphologies associated with apical polar growth and reduced lateral wall patterning. causal_graphs: - graph_id: irregular_shaped_loss_of_patterning title: Irregular-shape loss of wall patterning description: DOI-backed graph linking reduced or stochastic cell-wall patterning to inconsistent, irregular cell geometry. nodes: - node_id: irregular_shaped_trait label: irregular shaped node_type: TRAIT grounding: METPO:1000691 description: Inconsistent cell geometry across a population. - node_id: reduced_wall_patterning label: reduced cell-wall patterning node_type: BIOLOGICAL_PROCESS description: Diminished spatial control of peptidoglycan synthesis. - node_id: stochastic_growth label: stochastic growth node_type: BIOLOGICAL_PROCESS description: Cell-by-cell variation in growth-zone placement and extent. - node_id: variable_geometry label: variable cell geometry node_type: BIOLOGICAL_PROCESS description: Population-level variability in cell shape. - node_id: mreb_cytoskeleton_function label: MreB cytoskeletal function node_type: BIOLOGICAL_PROCESS description: MreB-mediated curvature sensing and spatial direction of lateral peptidoglycan insertion that maintains regular cell shape. - node_id: mreb_loss label: loss of MreB function node_type: BIOLOGICAL_PROCESS description: Inhibition or depletion of MreB cytoskeletal activity removing localized wall-insertion control. - node_id: synthase_hydrolase_imbalance label: peptidoglycan synthase-hydrolase imbalance node_type: BIOLOGICAL_PROCESS description: Disrupted coordination between peptidoglycan synthases and hydrolases destabilizing the cell wall. - node_id: polar_growth_organization label: polarized growth organization node_type: BIOLOGICAL_PROCESS description: Apical tip-organizing machinery that focuses cell-wall synthesis for ordered polar growth. - node_id: polar_growth_perturbation label: perturbation of polar growth determinants node_type: BIOLOGICAL_PROCESS description: Disruption of apical polar growth determinants leading to mispatterned wall synthesis. - node_id: wall_less_state label: wall-less (L-form) state node_type: STATE description: Absence of a rigid peptidoglycan wall removing canonical cell-shape constraints. edges: - subject: reduced_wall_patterning predicate: enables object: stochastic_growth description: Reduced patterning permits stochastic growth-zone placement. evidence: - reference: DOI:10.1146/annurev-cellbio-101011-155745 snippet: cell shape is genetically determined notes: Supports patterning loss as a driver of inconsistent shapes. predicate_id: RO:0002327 - subject: stochastic_growth predicate: produces object: variable_geometry description: Stochastic growth produces variable cell geometry. evidence: - reference: DOI:10.1111/j.1574-6976.2011.00298.x snippet: coryneform morphology notes: Supports irregular coryneform-like morphology arising from polar/apical growth without strong lateral patterning. predicate_id: METPO:2000202 - subject: variable_geometry predicate: manifests as object: irregular_shaped_trait description: Variable geometry across cells manifests the irregular-shaped trait. evidence: - reference: DOI:10.1146/annurev-cellbio-101011-155745 snippet: cell shape is genetically determined notes: Supports the trait endpoint. predicate_id: METPO:2007400 - subject: mreb_loss predicate: disrupts object: mreb_cytoskeleton_function description: Inhibition or depletion of MreB removes curvature sensing and localized cell-wall insertion control. evidence: - reference: DOI:10.1101/2024.11.22.624946 notes: MreB filaments sense curvature and direct localized cell-wall insertion; A22 inhibition of MreB polymerization alters width and causes rounding/loss of rod shape. - subject: mreb_loss predicate: causes object: irregular_shaped_trait description: Loss of MreB-mediated localized PG insertion removes rod-shape maintenance, yielding rounding and heterogeneous morphologies. evidence: - reference: DOI:10.1101/2024.11.22.624946 notes: Inhibition of MreB polymerization causes rounding/loss of rod shape across model bacteria; a broadly conserved shape-maintenance module. predicate_id: biolink:causes - subject: synthase_hydrolase_imbalance predicate: contributes to object: reduced_wall_patterning description: Loss of coordination between peptidoglycan synthases and hydrolases degrades spatial control of wall synthesis. evidence: - reference: DOI:10.1038/s41467-023-41082-3 notes: Coordinated peptidoglycan synthases and hydrolases stabilize the bacterial cell wall; uncoupling them (e.g. excess hydrolase activity) accelerates loss of regular shape as a general loss-of-patterning mechanism. predicate_id: RO:0002326 - subject: polar_growth_perturbation predicate: disrupts object: polar_growth_organization description: Disruption of apical polar growth determinants disorganizes the tip-organizing center and wall-synthesis focusing. evidence: - reference: DOI:10.21203/rs.3.rs-3811693/v1 notes: Apical determinants stabilize the tip-organizing center; their perturbation is associated with abnormal branching and mispatterned wall synthesis in filamentous bacteria. - subject: polar_growth_perturbation predicate: produces object: variable_geometry description: Mispatterned apical wall synthesis from disrupted polar growth produces irregular, branched/bulged geometry. evidence: - reference: DOI:10.21203/rs.3.rs-3811693/v1 notes: Partial depletion of the polar scaffold DivIVA causes hyphal bulging and irregular branching, an irregular-shape outcome of disorganized polar growth. predicate_id: METPO:2000202 - subject: wall_less_state predicate: manifests as object: irregular_shaped_trait description: Absence of a cylindrical wall removes canonical shape constraints, yielding irregular, amoeboid morphology. evidence: - reference: DOI:10.1038/s42003-024-07279-y notes: Wall-less L-form cells have heterogeneous, amoeboid morphology; loss of the rigid wall removes shape constraints, a general consequence of wall absence. predicate_id: METPO:2007400 curation_history: - timestamp: '2026-05-05T01:35:46.898746+00:00' curator: seed_from_metpo action: SEEDED_FROM_METPO changes: imported from data/raw/metpo.owl (CLASS) llm_assisted: false - timestamp: '2026-05-11T22:45:00-07:00' curator: claude action: CURATED_CAUSAL_GRAPH changes: Added DOI-backed definition and causal graph linking reduced cell-wall patterning and stochastic growth to irregular morphology. llm_assisted: true - timestamp: '2026-05-20T03:35:31Z' curator: claude action: GROUND_CAUSAL_PREDICATES changes: Grounded 2 causal-edge predicate_id field(s) via mappings/predicate_grounding.tsv (RO:0002327×1, METPO:2000202×1). llm_assisted: true - timestamp: '2026-05-23T21:30:07Z' curator: claude action: GROUND_CAUSAL_PREDICATES changes: Grounded 1 causal-edge predicate_id field(s) via mappings/predicate_grounding.tsv (METPO:2007400×1). llm_assisted: true - timestamp: '2026-06-23T00:00:00Z' curator: claude action: ENRICH_CAUSAL_GRAPH changes: Added 6 evidence-backed generic edges (6 new nodes) from the deep-research report. llm_assisted: true - timestamp: '2026-06-24T17:21:13Z' curator: claude action: GROUND_CAUSAL_PREDICATES changes: Grounded 4 causal-edge predicate_id field(s) via mappings/predicate_grounding.tsv (biolink:causes×1, RO:0002326×1, METPO:2000202×1, METPO:2007400×1). llm_assisted: true