Production of green fluorescent protein by the methylotrophic bacterium Methylobacterium extorquens
Bibliographic record
Abstract
The production of green fluorescent protein (GFP) in Methylobacterium extorquens was studied by creating four different constructs using pJB3KmD, pRK310 and pVK101 vectors, as well as pLac and soluble methane monooxygenase (sMMO) promoters. Plasmids were introduced into the cells by electroporation. Expression of GFP by selected clones was evaluated by growing cells in complex or defined media. The use of pRK310 as an expression vector containing the lacZ promoter resulted in a 100-fold increase of GFP production when compared to cells containing the pLac-GFP-pJB3KmD construct. Higher production of GFP was observed also in cells containing pLac-GFP-pRK310 and pmmoX-GFP-pVK101 constructs. While the transcriptional regulation of the smmo gene in Methylosinus trichosporium OB3b is known to be copper-dependent, expression of GFP by M. extorquens clones harboring pmmoX-promoters was not strongly controlled by the presence of copper in the medium. The production of GFP was generally constant throughout the growth of M. extorquens carrying the pLac-GFP-pRK310 construct. GFP yields varied between 850 and 1000 μg of GFP g biomass−1. However, the yield of GFP in cells carrying pmmoX-GFP-pVK101 was somewhat reduced after the mid-exponential phase of growth.
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 | 0.000 | 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 | 0.001 |
| Research integrity | 0.001 | 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".