Anatoxin-producing and non-toxic strains of Microcoleus sp. coexist in benthic cyanobacterial mats in the Wolastoq (Saint John River, 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 in New Brunswick, Canada, was attributed to anatoxin exposure after they ingested benthic microbial mats found along the shore. Four samples of the material ingested by the dogs and from the vicinity were collected. Then, 15 non-axenic cyanobacterial isolates were obtained from the same material. Total DNA of the 19 samples was sequenced using Illumina technology. Metagenomic assemblies recovered near-complete Microcoleus genomes from 12 of the sequenced samples. The high average genomic sequence similarity (>95% identity at the nucleotide level) suggests that the 12 genomes are representatives of the same “genomic” Microcoleus species. The genetic repertoire to produce anatoxin-a and dihydroanatoxin-a was identified in 9 of these genomes. The capacity for anatoxin production was confirmed by LC-MS. The overall comparison revealed that genomes of the 9 toxigenic Microcoleus isolates contain a higher number of accessory genes than their 3 non-toxigenic relatives. These differences suggest that toxigenic Microcoleus variants from the Wolastoq would be more responsive to changing environments, nutrient limitation and/or bacteriophage infection. Our results suggest that the two Microcoleus strains inhabited the original benthic mats in similar relative abundances.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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 | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| 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".