Genomic characterization of coexisting anatoxin-producing and non-toxigenic Microcoleus subspecies in benthic mats from the Wolastoq, New Brunswick, Canada
Bibliographic record
Abstract
The presence of toxigenic benthic cyanobacteria in riverine ecosystems is an increasing concern around the world. In 2018, the death of three dogs along the Wolastoq (also known as the Saint John River) in New Brunswick, Canada, was attributed to anatoxin exposure after they ingested benthic microbial mats found along the shore. Here, we shotgun sequenced the DNA of 15 non-axenic cyanobacterial isolates derived from four anatoxin-containing benthic mat samples associated with the dog deaths. Anatoxins were produced by some of the isolates, but not all. We retrieved near-complete Microcoleus metagenome-assembled genomes (MAGs) from the isolates that are closely related to anatoxin-producing Microcoleus from the Cardrona River (New Zealand), although the Microcoleus MAGs from the Wolastoq varied in the presence/absence of the anatoxin-a biosynthesis cluster. Sequence similarity at the genomic level suggests that toxigenic and non-toxigenic Microcoleus MAGs from the Wolastoq belong to the same species but are separate subspecies. The toxigenic and nontoxic Wolastoq Microcoleus subspecies coexisted in the mat samples in similar relative abundance. Overall genomic comparisons revealed that toxigenic Microcoleus MAGs are longer and code for more accessory genes than their non-toxigenic relatives, suggesting a differential responsiveness to changing environments, stress conditions and nutrient availability.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".