TraitMech

TraitMech › PHYSIOLOGY

osmotaxis

traitmech:000592 · CLASS · PROPOSED

A motile phenotype in which active locomotion produces net migration in response to a spatial gradient in external osmotic conditions.

Trait evidence (3)

  • DOI:10.1016/s0014-4894(03)00031-6
    We find that promastigotes move towards concentrations of all substances tested and that this taxis requires the presence of an osmotic gradient.

    Abstract, exact-matched at Europe PMC (PMID:12706748); full text not inspected. The study concerns Leishmania mexicana promastigotes and supports migration requiring an osmotic gradient under the tested conditions. The authors reinterpret those responses as osmotaxis; this is not evidence that all chemical-gradient responses in Leishmania are osmotic, or that every substance or life stage elicits this behavior. No universal preferred osmolarity or natural-strain example is inferred from the abstract.

  • DOI:10.1016/j.exppara.2005.10.005
    These were able to respond to chemotaxic as well as to osmotaxic stimuli.

    Abstract, exact-matched at Europe PMC (PMID:16313904); full text not inspected. The antecedent is Leishmania promastigotes; the article identifies Leishmania amazonensis. The authors report distinguishing chemical from osmotic responses, supporting osmotaxis without collapsing all chemotaxis into it. Their receptor model and possible vector-development role are not established as universal mechanisms or required trait consequences.

  • DOI:10.1073/pnas.1620945114
    We discuss how the speed changes we observe can lead to steady-state bacterial accumulation.

    Abstract, exact-matched at Europe PMC (PMID:28874571); full text and supplement not systematically inspected. Escherichia coli motor and population-swimming measurements concern stepwise osmotic changes. The snippet states a proposed link from measured speed changes to accumulation, not a direct spatial-gradient migration result from those measurements. Osmokinesis and motor bias may contribute to osmotaxis but are not exact synonyms or sufficient evidence of net migration on their own; no molecular causal edge is inferred.

Provenance

Identifier source
TraitMech local identifier
Definition source
DOI:10.1016/s0014-4894(03)00031-6

Parent traits (1)

kg-microbe context

No kg-microbe node embedding matched this record in the 2026-04-25 deepwalk.

Discussions and Knowledge Gaps (2)

Open questions attached to this trait. Seeded by just knowledge-gap-scan and curated; see the corpus-wide index.

Separate osmotic migration from tolerance, kinesis and chemical specificity.

CURATION TODO OPEN osmotaxis-spatial-and-chemical-boundaries · raised by codex · 2026-10-04

Not yet attached to a section of this record — a curator sets attaches_to (e.g. causal_graphs#some_edge) so the gap shows beside the mechanism it concerns.

Osmotic stress survival, growth salinity preference, water balance, and speed or tumbling changes after a uniform shock do not alone establish net migration through a spatial gradient. Exclude passive transport, osmotic water movement and differential growth as sole evidence. Osmokinesis is not an exact synonym, even when it contributes to spatial redistribution. Solute-specific chemotaxis can coexist with osmotaxis, as the Barros study reports; the Leslie result does not negate it universally. The local chemotaxis record imposes flagellar motor switching, so motile is used as the verified broader parent. External equivalents remain unasserted pending authority and organismal-scope checks.

Verify strain and life-stage provenance before adding examples or mechanisms.

CURATION TODO OPEN osmotaxis-mechanism-and-canonical-strains · raised by codex · 2026-10-04

Not yet attached to a section of this record — a curator sets attaches_to (e.g. causal_graphs#some_edge) so the gap shows beside the mechanism it concerns.

The studies support a microbial osmotic-gradient response without identifying one universal receptor or movement apparatus. Inspect full studies and relevant supplements, distinguish spatial observations from temporal-shock measurements and model interpretations, and resolve taxon-paired protein accessions before adding molecular causal graphs. Verify unperturbed natural strain provenance and NCBI identity before adding canonical examples; promastigote observations must retain their life-stage restriction. A NONMECHANISTIC graph must not bypass those requirements.

Curation history

  1. · MINTED_TRAITMECH_ID · codex

    Added osmotaxis with three primary DOI citations and exact abstract snippets. Ignored-and-hidden searches and structured OWL review found no exact live record or METPO term. Reserved METPO:1054600 in v469. Distinguished spatial migration from uniform-shock motility measurements, retained coexistence with solute-specific chemotaxis, and deferred unverified strain examples, molecular mechanisms and external equivalents.