identifier: METPO:1000706
label: gliding
definition: A motile in which an organism moves smoothly along solid surfaces without
  flagella or pili.
definition_source: DOI:10.1146/annurev.micro.55.1.49
trait_category: MORPHOLOGY
term_kind: CLASS
mapping_status: REVIEWED
parent_traits:
- METPO:1000702
evidence:
- reference: DOI:10.1146/annurev.micro.55.1.49
  snippet: move actively over surfaces
  notes: Supports gliding as active surface movement without flagella.
canonical_examples:
- taxon_id: NCBITaxon:34
  taxon_label: Myxococcus xanthus
  note: "Primary model for bacterial gliding motility and multicellular development. Flavobacterium johnsoniae is a secondary model."
  reference: https://pmc.ncbi.nlm.nih.gov/articles/PMC103748/
causal_graphs:
- graph_id: gliding_surface_motility
  title: Gliding surface motility mechanism
  description: Evidence-backed causal sketch linking gliding to solid surfaces, cell-envelope
    motors, surface adhesins, and type IX secretion/gliding systems.
  nodes:
  - node_id: gliding_trait
    label: gliding
    node_type: TRAIT
    grounding: METPO:1000706
    description: Smooth movement along solid surfaces without flagella or pili.
  - node_id: solid_surface
    label: solid surface
    node_type: ENVIRONMENTAL_FACTOR
    description: Surface substrate on which gliding movement occurs.
  - node_id: gliding_motility_machinery
    label: gliding motility machinery
    node_type: GENE_OR_PROTEIN
    description: Molecular machinery that produces surface translocation without flagella.
  - node_id: surface_adhesins
    label: surface adhesins
    node_type: GENE_OR_PROTEIN
    description: Cell-surface proteins moved or engaged during gliding.
  - node_id: type_ix_secretion_system
    label: type IX secretion system
    node_type: GENE_OR_PROTEIN
    description: Secretion-associated machinery linked to Flavobacterium gliding.
  - node_id: proton_motive_force
    label: proton motive force
    node_type: STATE
    description: Electrochemical gradient powering some gliding motors.
    grounding: METPO:1007500
  - node_id: helical_track
    label: helical conveyor track
    node_type: CELLULAR_LOCALIZATION
    description: Filamentous/multirail track structure in the cell envelope along
      which surface adhesins are translocated during gliding.
  - node_id: substratum_coupling
    label: substratum coupling and traction
    node_type: BIOLOGICAL_PROCESS
    description: Engagement of surface adhesins with the solid substratum to generate
      the traction that drives cell movement.
  - node_id: cell_propulsion
    label: cell propulsion
    node_type: BIOLOGICAL_PROCESS
    description: Forward, often screw-like, translocation of the cell body resulting
      from gliding machinery activity.
  - node_id: gliding_gene_complement
    label: gliding machinery gene complement
    node_type: EXPERIMENTAL_FACTOR
    description: Presence of the core gliding/secretion machinery gene set in a genome,
      used to predict gliding capacity.
  edges:
  - subject: solid_surface
    predicate: enables context for
    object: gliding_trait
    description: Gliding is a mode of active bacterial movement over surfaces.
    evidence:
    - reference: DOI:10.1146/annurev.micro.55.1.49
      snippet: move actively over surfaces
      notes: Supports surface movement as defining context for gliding.
  - subject: gliding_motility_machinery
    predicate: enables
    object: gliding_trait
    description: Specialized machinery drives bacterial surface movement without flagella.
    evidence:
    - reference: DOI:10.1016/j.cub.2016.12.035
      snippet: without using flagella, pili, or other external appendages
      notes: Supports gliding as a distinct motility mode.
    predicate_id: RO:0002327
  - subject: surface_adhesins
    predicate: transmit force for
    object: gliding_trait
    description: Surface adhesins couple internal motors to external substrates.
    evidence:
    - reference: DOI:10.1038/s41579-021-00626-4
      snippet: moves adhesins along the cell surface
      notes: Review summarizes gliding models using moving surface adhesins.
  - subject: type_ix_secretion_system
    predicate: contributes to
    object: gliding_motility_machinery
    description: Type IX secretion-associated components contribute to some gliding
      systems.
    evidence:
    - reference: DOI:10.1038/s41579-021-00626-4
      snippet: type 9 secretion and gliding motility
      notes: Supports linkage between type IX secretion and gliding machinery.
    predicate_id: RO:0002326
  - subject: proton_motive_force
    predicate: enables
    object: gliding_motility_machinery
    description: Proton motive force can power gliding motility motors.
    evidence:
    - reference: DOI:10.1038/s41579-021-00626-4
      snippet: proton-driven motor that powers type 9 secretion and gliding motility
      notes: Supports proton-driven gliding machinery in reviewed systems.
    predicate_id: RO:0002327
  - subject: helical_track
    predicate: guides
    object: surface_adhesins
    description: Adhesins are translocated along an envelope-associated filamentous
      track during gliding.
    evidence:
    - reference: DOI:10.1038/s42003-023-04472-3
      notes: Filamentous multirail structures in the cell envelope are associated
        with the gliding machinery and SprB adhesin translocation.
  - subject: surface_adhesins
    predicate: enables
    object: substratum_coupling
    description: Surface adhesins engage the substratum to generate traction.
    evidence:
    - reference: DOI:10.1126/sciadv.abq0619
      notes: Surface adhesin at bacterial focal adhesions immobilizes motility complexes
        against the substratum to generate traction.
    predicate_id: RO:0002327
  - subject: substratum_coupling
    predicate: causes
    object: cell_propulsion
    description: Traction at substratum-coupled adhesins drives forward movement of
      the cell body.
    evidence:
    - reference: DOI:10.1371/journal.pbio.3001443
      notes: Proton-dependent motors power adhesin surface translocation that propels
        the cell during gliding.
    predicate_id: biolink:causes
  - subject: cell_propulsion
    predicate: realizes
    object: gliding_trait
    description: Propulsion of the cell body along a surface constitutes the gliding
      phenotype.
    evidence:
    - reference: DOI:10.1371/journal.pbio.3001443
      notes: Adhesin surface translocation produces the smooth surface movement characteristic
        of gliding.
  - subject: gliding_gene_complement
    predicate: predicts
    object: gliding_trait
    description: Presence of the core gliding/secretion machinery gene set predicts
      gliding capacity from genomes.
    evidence:
    - reference: DOI:10.1021/acsomega.3c05155
      notes: T9GPred predicts gliding motility from an 11-protein mandatory component
        set across Bacteroidetes genomes.
curation_history:
- timestamp: '2026-05-05T01:35:46.907644+00:00'
  curator: seed_from_metpo
  action: SEEDED_FROM_METPO
  changes: imported from data/raw/metpo.owl (CLASS)
  llm_assisted: false
- timestamp: '2026-05-11T00:00:00-07:00'
  curator: codex
  action: CURATED_WITH_LITERATURE
  changes: Reviewed gliding trait and added DOI-backed causal graph for surface gliding
    machinery, adhesins, type IX secretion, and proton motive force.
  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, RO:0002326×1).
  llm_assisted: true
- timestamp: '2026-05-24T04:41:04Z'
  curator: claude
  action: GROUND_CAUSAL_NODES
  changes: Grounded 1 causal-node grounding field(s) via mappings/node_grounding.tsv
    (METPO:1007500×1).
  llm_assisted: true
- timestamp: '2026-05-26T02:30:13Z'
  curator: claude
  action: RETYPE_CAUSAL_NODES
  changes: 'Re-typed 1 causal-node node_type field(s) to align with CausalNodeTypeEnum
    semantics: proton motive force: BIOLOGICAL_PROCESS → STATE ×1.'
  llm_assisted: true
- timestamp: '2026-05-26T05:00:48Z'
  curator: claude
  action: RENAME_PREDICATE_LABELS
  changes: 'Renamed 1 causal-edge predicate label(s) to align with existing groundings:
    powers → enables ×1.'
  llm_assisted: true
- timestamp: '2026-05-26T05:00:50Z'
  curator: claude
  action: GROUND_CAUSAL_PREDICATES
  changes: Grounded 1 causal-edge predicate_id field(s) via mappings/predicate_grounding.tsv
    (RO:0002327×1).
  llm_assisted: true
- timestamp: '2026-06-17T04:09:44Z'
  curator: claude
  action: REMOVE_REDUNDANT_SYNONYM
  changes: Removed 1 synonym(s) whose text duplicated the label (seeder redundancy;
    no information lost).
  llm_assisted: true
- timestamp: '2026-06-23T00:00:00Z'
  curator: claude
  action: ENRICH_CAUSAL_GRAPH
  changes: Added 5 evidence-backed generic edges (4 new nodes) from the deep-research
    report.
  llm_assisted: true
- timestamp: '2026-06-24T17:21:13Z'
  curator: claude
  action: GROUND_CAUSAL_PREDICATES
  changes: Grounded 2 causal-edge predicate_id field(s) via mappings/predicate_grounding.tsv
    (RO:0002327×1, biolink:causes×1).
  llm_assisted: true