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toxicyst discharge

traitmech:000685 · CLASS · PROPOSED

A physiological phenotype in which a microbial cell releases material from toxicysts, its offensive extrusomes, to the cell exterior.

Trait evidence (3)

  • DOI:10.1111/jeu.12106
    we isolated the discharge of the toxicysts from living cells

    PMID:24512001. Scientific Abstract read directly in PubMed and Europe PMC (EXT_ID:24512001 AND SRC:MED); source, title and DOI agree. Coleps hirtus discharge was collected and tested against other ciliates. This supports extracellular release from living cells, not merely possession of an organelle or toxicity of a whole-cell extract. Abstract-only access: full Methods and figures were not inspected; the institutional postprint at https://hdl.handle.net/11393/192287 is access-restricted. The reported chemical mixture is not a universal toxicyst cargo.

  • DOI:10.1007/BF01279249
    Injection of Ca2+ evoked discharge of toxicysts, if the site of the injection was the periphery region of the proboscis.

    Scientific Summary read directly on the publisher page; Ca2+ represents its rendered superscript charge. Methods, Results and captions also read in the author-upload full-text transcript at https://www.researchgate.net/publication/227062328_Ca2_triggers_toxicyst_discharge_in_Didinium_nasutum. Figures were not visually inspected. Didinium nasutum pressure injection near the proboscis periphery produced discharge in 8/11 cells versus 1/11 calcium-free controls; cell-body and central-proboscis injections did not. Iontophoretic injection caused damage and cytoplasm outflow, motivating pressure injection. These are assay-specific observations, not a universal calcium requirement or proof of a particular fusion protein. No PMID was resolved by the exact DOI query.

  • DOI:10.1186/s12915-024-01904-2
    However, our understanding of the genetic processes and specific toxins involved in toxicyst formation and discharge is still limited.

    PMID:38715037, PMC11077807. Scientific Abstract, Background, morphology Results, Discussion and collection/TEM Methods read in primary HTML/fullTextXML. Figure 1 was visually inspected: A-C are drawings, whereas D-F are TEM images of fixed Litonotus. The drawing of discharge is not direct imaging of release. Sequence and expression associations motivate toxin/transport hypotheses, not experimentally resolved discharge mechanisms. Genomics supplements were not inspected and are not used for accessions, prevalence or functional assignments.

Provenance

Identifier source
TraitMech local identifier
Definition source
DOI:10.1111/jeu.12106

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.

Resolve the exocytosis hierarchy without equating all extrusome types.

CURATION TODO OPEN toxicyst-discharge-scope-and-parent · raised by codex · 2026-10-08

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.

Parent phenotype METPO:1000059 is conservative. The 2024 Background describes telescopic discharge and/or membrane fusion; its Discussion reports fusion observations. These statements do not establish that every toxicyst-discharge phenotype satisfies the fusion-pore definition of exocytosis traitmech:000637. That placement remains unresolved, not excluded. Mere toxicyst possession, docking, predation, prey injury or cell lysis does not alone establish this trait. Preserve the organelle-specific scope rather than equating mucocyst discharge traitmech:000684, trichocyst discharge traitmech:000683, pexicysts or haptocysts. Historical type-I/II terminology needs reconciliation before synonym or hierarchy expansion. No exact synonyms, xrefs or organism-level disjointness are asserted. Prey killing and complete emptying are not universal defining requirements.

Resolve experimental culture provenance and protein-level mechanisms.

KNOWLEDGE GAP OPEN toxicyst-discharge-provenance-and-mechanism · raised by codex · 2026-10-08

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.

Natural provenance and strain-level taxonomy of the positive experimental cultures remain unchecked; no canonical examples are assigned. Wild-collected genomic material is not by itself a positive discharge assay for that isolate. Gene-family expansion, expression and predicted toxin annotations alone do not establish toxicyst discharge or a causal protein. A future graph needs source-specific perturbations and taxon-paired accessions, distinguishing assembly, triggering, extrusion and toxin action. Mechanism is deferred, not claimed absent. Do not transfer a calcium threshold, cargo chemistry or ecological function between species without evidence.

Curation history

  1. · MINTED_TRAITMECH_ID · codex

    Added toxicyst discharge with three primary DOI sources and directly checked abstract/Summary snippets. Ignored-and-hidden main/worktree/open-PR checks support 000685 and v561 block 1063800-1063899. Retained phenotype parent while making the exocytosis placement explicit and unresolved. Distinguished discharge from damage, organelle possession and sequence-based predictions. Existing records unchanged. Timestamp is observed UTC.

Recorded curation sessions

  • · codex
    • CREATE — Add source-bounded toxicyst discharge

      Created traitmech:000685 with DOI:10.1111/jeu.12106, DOI:10.1007/BF01279249 and DOI:10.1186/s12915-024-01904-2; directly checked scientific Abstract/Summary snippets. Reserved v561 and METPO:1063800-1063899 after ignored-and-hidden worktree and open-head checks. Retained phenotype parent with explicit unresolved exocytosis classification. Distinguished discharge from injury, organelle possession and sequence predictions. No canonical examples, xrefs or protein graph without verified provenance and mechanism. Existing records unchanged.

    Read this curation session