Single enzyme molecule assay with time resolution using capillary electrophoresis
Bibliographic record
Abstract
Abstract The continuous flow assay is a capillary electrophoresis-based methodology for the simultaneous measurement of the catalytic rate and electrophoretic mobility of individual molecules of the enzyme β-galactosidase. The method also provides time resolution. This method was used to measure the distribution of single-molecule activities and mobilities of a population of the wild-type Escherichia coli β-galactosidase. The catalytic rate was found to vary over time at an elevated temperature, suggesting a switching between different conformations. The successive incubation of individual molecules at 27°C, 45°C, and again at 27°C was found to convert molecules from one form with a stable catalytic rate to a different form with a different stable catalytic rate. Incubation at higher temperatures was found to cause a sudden and catastrophic loss in activity, which was consistent with denaturation. Increasing the incubation temperature over time was used to generate an Arrhenius plot for a single enzyme molecule. Finally, assaying the enzyme as the slow-release inhibitor d -galactal dissociated allowed for the measurement of the activity of individual subunits within a single molecule.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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 | 0.002 | 0.002 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.002 | 0.002 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.002 | 0.001 |
| Open science | 0.002 | 0.001 |
| Research integrity | 0.002 | 0.003 |
| Insufficient payload (model declined to judge) | 0.002 | 0.002 |
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".