Control of bioluminescence in <i>Vibrio fischeri</i> by the LuxO signal response regulator
Bibliographic record
Abstract
Bioluminescence in the marine bacterium Vibrio fischeri is controlled by the excretion of a N-acyl homoserine lactone (HSL) autoinducer which interacts with a regulator, LuxR, and activates transcription of the lux operon at high-cell density. This system has become the prototype for quorum sensing in many bacteria. Although light emission in Vibrio harveyi is also regulated by a N-acyl-HSL inducer, in sharp contrast, a completely different and more complex system is involved in quorum sensing which is mediated via LuxO, the response regulator of a phosphorelay signal transduction system. In the present work, luxO and the overlapping luxU gene, also involved in the phosphorelay system in V. harveyi, have been discovered in V. fischeri. By gene replacement technology, a V. fischeri luxO- mutant was generated whose phenotype was similar to that of V. harveyi luxO- showing that LuxO is involved in control of luminescence in V. fischeri. This mutant could be complemented with luxO from either V. fischeri or V. harveyi resulting in the restoration of the dependence of luminescence intensity on cell density. In contrast to V. harveyi luxO-, light emission of V. fischeri luxO- was stimulated by the N-acyl-HSL autoinducer indicating that luxO is part of a second signal transduction system controlling luminescence in this species. The presence of a luxO-based phosphorelay regulatory system as well as the luxR-based system in V. fischeri suggests that the former system, originally discovered in V. harveyi, may be a general regulatory mechanism in luminescent bacteria.
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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".