Overproduction in <i>Escherichia coli </i>of the pectin methylesterase A from <i>Erwinia chrysanthemi</i> 3937: One-step purification, biochemical characterization, and production of polyclonal antibodies
Bibliographic record
Abstract
Pectin methylesterase A (EC 3.1.1.11), one of the pathogenicity factors of Erwinia chrysanthemi strain 3937, was purified to homogeneity using one-step chromatography on cross-linked pectate. The purified protein showed maximum activity at pH 8-9, 50 degrees C, 50-100 mM monovalent cations or 5-10 mM divalent cations, and on a 50% esterified pectin. A particular effect of Ca2+ and Zn2+ on PMEA activity, due to the formation of a pectin gel, was observed. A Km value of 0.03% and 0.051% was determined at pH 6 and 7.6, respectively, using the same substrate. Polyclonal antibodies raised against the PMEA from E. chrysanthemi strain 3937 were produced. It recognized PMEs from Erwinia species, but did not cross-react with PME of fungal or plant origin, and will therefore be a useful tool to immunolocalize the protein during plant-pathogen interactions.
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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".