Isolation of a strain of <i>Agrobacterium tumefaciens</i> (<i>Rhizobium radiobacter</i>) utilizing methylene urea (ureaformaldehyde) as nitrogen source
Bibliographic record
Abstract
Methylene ureas (MU) are slow-release nitrogen fertilizers degraded in soil by microbial enzymatic activity. Improved utilization of MU in agricultural production requires more knowledge about the organisms and enzymes responsible for its degradation. A Gram-negative, MU-degrading organism was isolated from a soil in Sacramento Valley, California. The bacterium was identified as Agrobacterium tumefaciens (recently also known as Rhizobium radiobacter) using both genotypic and phenotypic characterization. The pathogenic nature of the organism was confirmed by a bioassay on carrot disks. The MU-hydrolyzing enzyme (MUase) was intracellular and was induced by using MU as a sole source of nitrogen. The bacterial growth was optimized in NH4Cl, urea, or peptone, whereas the production and specific activity of MUase were maximized with either NH4Cl or urea as a nitrogen source. The result has a practical significance, demonstrating a potential to select for this plant pathogen in soils fertilized with MU.
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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) | 0.001 | 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 | 0.001 |
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".