identifier: traitmech:000703 label: expansion-driven sliding motility definition: A phenotype in which a microbial population spreads across a supporting surface through passive displacement of cells by expansive forces generated within the colony, without active locomotory propulsion of the displaced cells. definition_source: DOI:10.1111/1758-2229.70214 trait_category: MORPHOLOGY term_kind: CLASS mapping_status: PROPOSED parent_traits: - METPO:1000059 evidence: - reference: DOI:10.1111/1758-2229.70214 snippet: Passive sliding motility allows Mycobacterium smegmatis to spread over soft agar surfaces. notes: Pollitt et al. 2025, PMID:41152213, PMC12568390; scientific abstract, not graphical abstract. Full text, Figure 1 and the actual DOCX supplement were inspected. Results 2.8-2.9 interpret digitate-colony expansion as hydraulic displacement, not a direct force measurement; unobserved division does not establish absent growth. Supplementary Methods identify mc2 155. The Figure 1 comparison varies both gel material and concentration, not material alone. The qualified definition includes this interpretation without making cell-division pressure universal. Raw movies were not reanalyzed. Qualified MED, Crossref and the retrieved publisher page exposed no linked correction or retraction at the 2026-10-11 check. - reference: DOI:10.1186/1471-2180-6-31 snippet: sliding motility is a passive mode of translocation for spreading over surfaces. notes: Fall et al. 2006, PMID:16545127, PMC1501027; Background's source-attributed terminology, not an abstract quote. Results and Methods directly describe surface expansion of constructed B. subtilis DS64 hag-replacement material. Growth-associated, surfactin-dependent spreading supports the conventional case, not a universal transporter or surfactant requirement. Actual Figure 1 says 24 hours, whereas its caption and Results say 18 hours; retain this unresolved discrepancy. Proposed plant-root benefit is not observed natural colonization. Qualified MED, Crossref and the retrieved publisher page exposed no linked correction or retraction at the 2026-10-11 check. discussions: - discussion_id: expansion-sliding-scope-and-naming prompt: Retain the qualified expansion-driven scope without settling broader sliding terminology. kind: CONTROVERSY status: OPEN rationale: 'The label is deliberately qualified: Kovacs et al. include gravity-assisted droplet surfing under sliding, whereas Hennes et al. distinguish it by driving force. Neither unqualified sliding nor surfing is asserted as an exact synonym here. Translation of an entire droplet under gravity alone is outside this expansion-driven definition. Fall''s Background uses motility as a broader umbrella than current METPO:1000701 independent movement and METPO:1000702 energy-dependent independent movement; phenotype is therefore the conservative parent. This is not swimming, active gliding, swarming or twitching, and does not require absence of locomotory appendages from the organism. Different modes can coexist; no organism-level disjointness is asserted. Colony diameter, wetting, bulk advection or a sequence feature alone is insufficient. The letters document terminology, not additional experimental replication.' evidence: - reference: DOI:10.1073/pnas.1710371114 evidence_source: full_text snippet: we therefore propose considering the finding of Hennes et al. (1) as a novel example of sliding motility notes: Kovacs et al. 2017 letter, E8802, penultimate paragraph; publisher PDF at the authors' DTU repository. A proposed broader naming convention, not an independent experiment. - reference: DOI:10.1073/pnas.1712278114 evidence_source: full_text snippet: gravity is the driving force of surfing notes: Hennes et al. 2017 reply, first bullet; author-hosted PDF. Contrasting physical classification, not experimental replication. posed_by: codex posed_date: '2026-10-11' - discussion_id: expansion-sliding-historical-metpo-identity prompt: Resolve upstream identity without reviving deprecated sliding identifiers. kind: CURATION_TODO status: OPEN rationale: Pinned and current METPO contain deprecated METPO:0000096, METPO:000097 and METPO:1000388, without replacement annotations. Their reason codes were assigned by ID era in generator commit 38fbfb82c6cc962009582eb7f8652e48ede0f9c2, not by a sliding-specific biological assessment. https://github.com/berkeleybop/metpo/issues/521 still disputes this metadata; issue 271 requests motility coverage. Neither authorizes reactivation or resolves equivalence to this qualified class. Independent primary evidence supports the present scope, and no active exact replacement was found in the inspected ontology and pending proposals. Keep historical IDs out of xrefs and replaces; the new v579 proposal is not an upstream acceptance. posed_by: codex posed_date: '2026-10-11' - discussion_id: expansion-sliding-examples-and-mechanisms prompt: Ground taxon-specific examples and causal branches before adding a graph. kind: KNOWLEDGE_GAP status: OPEN rationale: DS64 is engineered hag-replacement material. For mc2 155, the first-person provenance account DOI:10.1128/microbiolspec.MGM2-0037-2013 describes a laboratory-selected, plasmid-cured mutant derivative. Neither is presented as an unqualified natural canonical example. These qualifications do not invalidate the observed phenotype. No exact taxon-paired protein branch is established here, and the hydraulic molecular mechanism remains unresolved. Defer the graph rather than impose one lineage's mechanism or use NONMECHANISTIC to bypass grounding. Gene presence, appendage absence and predicted motility annotations cannot establish observed passive surface expansion. External equivalences remain unasserted. posed_by: codex posed_date: '2026-10-11' curation_history: - timestamp: '2026-10-11T21:19:38Z' curator: codex action: MINTED_TRAITMECH_ID changes: Added qualified expansion-driven sliding with two primary DOI-backed studies and directly checked snippets. Reserved 000703, v579 and 1065600-1065699 after ignored/hidden worktree and pending-PR checks. Historical deprecated identities are not reused. Naming controversy, strain provenance and mechanism gaps remain explicit. Existing traits unchanged; timestamp is the observed UTC curation decision. llm_assisted: true