Gene expression of the arsenic resistance operon in<i>Chromobacterium violaceum</i>ATCC 12472
Bibliographic record
Abstract
Chromobacterium violaceum ATCC 12472 presents an arsRCB-type operon, which is involved in arsenic resistance. The regulating protein of this resistance system (ArsR) does not have the small conserved site (ELCVDCL) to link to the metalloid, as observed in Escherichia coli, and is thus considered to be an atypical ArsR protein, like that observed in Acidithiobacillus ferrooxidans. In the present study, the gene expression profile of the ars operon under induction at different concentrations of arsenite - As(III) - was obtained via real-time PCR (TaqMan), by correlating the threshold cycle (Ct) values of induced and uninduced (control) samples. Through linear regression analysis (R2 = 0.9926), the gene expression profile of the ars operon showed clearly that the 0.125 micromol/L concentration of As(III) was sufficient to provoke a 4-fold increase in the resistance system, and a further increase in concentration resulted in an increase of up to 53-fold in transcription rates. The relation between resistance and induction of the ars operon indicates that the increased resistance to As(III) is associated with the increase in the number of transcripts.
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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 | 0.001 |
| 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".