identifier: traitmech:000586
label: chemokinesis
definition: A motile phenotype in which swimming speed changes in response to chemical
  concentration, without requiring directional bias along a chemical gradient.
definition_source: DOI:10.1038/ismej.2013.210
trait_category: PHYSIOLOGY
term_kind: CLASS
mapping_status: PROPOSED
parent_traits:
- METPO:1000702
evidence:
- reference: DOI:10.1038/ismej.2013.210
  snippet: chemokinesis is the ability to change swimming speed in response to a change
    in chemical concentration.
  notes: Discussion, page 1005, visually checked in the author-hosted published PDF
    at https://stockerlab.ethz.ch/wp-content/uploads/2015/03/49.-Garren_etal_ISME_2014.pdf.
    This bacterial usage defines chemokinesis by speed, in contrast to chemotactic
    directional bias. The two responses can coexist. This citation supports identity;
    no independent reanalysis of its supplementary assays is claimed.
- reference: DOI:10.1073/pnas.1602307113
  snippet: Chemokinesis was also observed in the absence of a chemical gradient
  notes: SI Text, Chemokinesis, page 3 of 9; full article and SI inspected at https://pmc.ncbi.nlm.nih.gov/articles/PMC4978249/.
    Figure S5 and its caption were visually checked in the author PDF at https://stockerlab.ethz.ch/wp-content/uploads/2017/05/89._Son_atall.pdf
    (SI page 7 of 9). The uniform-serine assay supports a speed response without a
    gradient. Model block removals are in silico mutants, not biological gene deletions.
    YM4 cells were harvested in late exponential phase and resuspended in TMN motility
    medium, pH 7.5; Figure S5 uses uniform 5 micromolar serine at 600 mM sodium. YM4
    is a laboratory mutant deficient in lateral flagella, as documented separately
    by DOI:10.7717/peerj.17126; it is retained as qualified experimental evidence,
    not a natural canonical example.
- reference: DOI:10.1038/s41396-021-01024-7
  snippet: Thus, we hypothesize that the metabolism of mucus substrate stimulates
    Na+-NQR activity, which in turn enables sustained chemokinesis.
  notes: Discussion, page 3677, visually checked at https://stockerlab.ethz.ch/wp-content/uploads/2022/03/141.-Cherry-Gao_Coral-Muscus.pdf.
    The plus is superscript in the typeset sodium notation and plain text in extraction.
    The following sentence requires experimental testing of this hypothesis. Transcript
    associations do not establish a causal protein pathway; no supplementary gene-level
    result is curated here.
- reference: DOI:10.7717/peerj.17126
  snippet: two strains showing defects in the lateral flagellum (VIO5 and YM4)
  notes: 'Abstract, PMID:38515459. This primary genomic study identifies YM4 as a
    laboratory strain with defective lateral flagellation. It supplies strain provenance,
    not a chemokinesis measurement. The Son observation must not be generalized to
    unperturbed Vibrio alginolyticus. Canonical examples are deferred pending separate
    verification of a natural exemplar (issue #1653).'
discussions:
- discussion_id: chemokinesis-speed-and-taxis-boundaries
  prompt: Preserve the source-defined speed response and its distinction from taxis.
  kind: CURATION_TODO
  status: OPEN
  rationale: This record follows the swimming-speed usage in Garren, Son and Gao.
    Chemotaxis (traitmech:000086) concerns directional bias. No equivalence, disjointness
    or parent-child relation between them is asserted. A speed response can occur
    with or without chemotaxis and need not always be an increase. Existing research
    also uses chemokinesis more broadly for changes in turning frequency. Reconcile
    that broader usage, orthokinesis and klinokinesis before adding synonyms, narrower
    terms or xrefs; do not equate a turning-only response with this speed definition.
  posed_by: codex
  posed_date: '2026-10-04'
- discussion_id: chemokinesis-mechanism-grounding
  prompt: Distinguish observed behavior from model ablations and molecular hypotheses.
  kind: CURATION_TODO
  status: OPEN
  rationale: Son's computational removal of functional blocks is not a gene-knockout
    experiment. Gao's Na+-NQR explanation is explicitly hypothetical, with further
    experimental work requested. A mechanistic graph is deferred pending source-backed
    causal edges and eligible taxon-paired protein examples. Do not borrow the enterobacterial
    Che pathway from chemotaxis, infer causality from transcript changes, or use NONMECHANISTIC
    to bypass the protein-coverage requirement. No universal receptor is asserted.
  posed_by: codex
  posed_date: '2026-10-04'
curation_history:
- timestamp: '2026-10-04T04:08:00Z'
  curator: codex
  action: MINTED_TRAITMECH_ID
  changes: Added chemokinesis with three primary DOI citations, contiguous snippets
    and a uniform-serine YM4 example at verified species taxon 663. Ignored-and-hidden
    searches found only a chemotaxis boundary mention, not an exact record or METPO
    class. Reserved METPO:1054000 in proposal v463. Kept speed, directional bias,
    computational ablations and molecular hypotheses separate.
  llm_assisted: true
- timestamp: '2026-10-04T04:09:00Z'
  curator: codex
  action: QUALIFY_EXPERIMENTAL_STRAIN
  changes: 'Addressed adversarial review #1653: added primary YM4 strain provenance,
    removed the laboratory-mutant canonical example, and retained its uniform-serine
    speed response in qualified evidence. Natural canonical exemplars remain deferred.'
  llm_assisted: true