Toxoflavin secreted by <i>Pseudomonas alcaliphila</i> inhibits growth of <i>Legionella pneumophila</i> and its host <i>Vermamoeba vermiformis</i>
Bibliographic record
Abstract
ABSTRACT Legionella pneumophila is a natural inhabitant of water systems. From there, it can be transmitted to humans by aerosolization resulting in severe pneumonia. Most large outbreaks are caused by cooling towers contaminated with L. pneumophila . The resident microbiota of the cooling tower is a key determinant for the colonization and growth of L. pneumophila . The genus Pseudomonas correlates negatively with the presence of L. pneumophila , but it is not clear which species is responsible. Therefore, we identified the Pseudomonas species inhabiting 14 cooling towers using a Pseudomonas -specific 16S rRNA amplicon sequencing strategy. Cooling towers free of L. pneumophila contained a high relative abundance of members from the Pseudomonas alcaliphila/oleovorans phylogenetic cluster. In vitro , P. alcaliphila JCM 10630 inhibited the growth of L. pneumophila on agar plates. Analysis of the P. alcaliphila genome revealed the presence of a genes cluster predicted to produce toxoflavin. L. pneumophila growth was inhibited by pure toxoflavin and by extract from P. alcaliphila culture found to contain toxoflavin by LC-ESI-MS. In addition, toxoflavin inhibits growth of Vermameoba vermiformis , a host cell of L. pneumophila . Our study indicates that P. alcaliphila may be important to restrict growth of L. pneumophila in water systems through the production of toxoflavin. A sufficiently high concentration is likely not achieved in the bulk water but might have a local inhibitory effect such as in biofilm.
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) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.003 |
| Research integrity | 0.001 | 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".