The attenuated virulence of a Burkholderia cenocepacia K56-2 paaABCDE mutant is due to inhibition of quorum sensing by release of phenylacetic acid
Bibliographic record
Abstract
The phenylacetic acid degradation pathway of Burkholderia cenocepacia is necessary for full pathogenicity of B. cenocepacia in nematode; however, the reasons of such requirements are unknown. Unlike wild type B. cenocepacia, a deletion mutant of the phenylacetyl-CoA monooxygenase complex (ΔpaaABCDE) released phenylacetic acid extracellularly in conditions that allow infection in Caenorhabditis elegans. Addition of phenylacetic acid further decreased the pathogenicity of the ΔpaaABCDE, which cannot metabolize phenylacetic acid, but did not affect the wild type, due to phenylacetic acid consumption. Detection of acyl-homoserine lactones was reduced in spent medium from ΔpaaABCDE compared to that of the wild type strain. Phenotypes repressed in ΔpaaABCDE, protease activity and pathogenicity against C. elegans, increased with the addition of exogenous N-octanoyl-L-homoserine lactone. Thus, it was demonstrated that the attenuated phenotype of B. cenocepacia ΔpaaABCDE is due to quorum sensing inhibition by release of phenylacetic acid, affecting N-octanoyl-L-homoserine lactone signaling.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| 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) | 0.001 | 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 source (direct Gemma or distilled Codex), 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".