Identification and characterization of the regulatory elements of the inducible acetamidase operon from Mycobacterium smegmatis
Bibliographic record
Abstract
The highly inducible acetamidase promoter from Mycobacterium smegmatis has been used as a tool in the study of mycobacterial genetics. The 4.2 kb acetamidase operon contains four putative open reading frames (ORFs) (amiC, amiA, amiD, and amiS) upstream of the 1.2 kb acetamidase ORF (amiE). In this article, using electrophoretic mobility shift assay and promoter probe analyses with a lacZ reporter system, we show the position of three putative operators within the acetamidase operon in M. smegmatis. Results from these studies reinforce previous findings about the involvement of multiple promoters in the regulation of acetamidase gene expression. Each of the identified operators are positioned upstream of the respective promoter reported in previous studies. We also found that the crude cell lysate of M. smegmatis containing potential regulators, obtained from bacteria grown under inducing or noninducing conditions, binds to specific operators. The binding affinity of each operator with its cognate regulator is significantly different from the other. This supports not only the previous model of acetamidase gene regulation in M. smegmatis but also explains the role of these operators in controlling the expression of respective promoters under different growth conditions.
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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 | 0.001 |
| 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) | 0.000 | 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 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".