Increased glucose utilization and cell growth of <i>Corynebacterium glutamicum</i> by modifying the glucose-specific phosphotransferase system (PTS<sup>Glc</sup>) genes
Bibliographic record
Abstract
The phosphoenolpyruvate:glucose phosphotransferase system (PTS Glc ) is the major pathway of glucose uptake in Corynebacterium glutamicum. This study investigated glucose consumption rate, cell growth, and metabolite changes resulting from modification of PTS Glc . The classical l-lysine producer C. glutamicum XQ-8 exhibited low glucose consumption, cell growth, and l-lysine production rates, whereas these parameters were significantly increased during cultivating on glucose plus maltose, through inactivation of SugR, or by overexpression of PTS Glc genes. XQ-8sugR::cat/pDXW-8-ptsI exhibited the highest increase in glucose consumption, growth rate, and l-lysine production, followed by XQ-8sugR::cat/pDXW-8-ptsG. However, overexpression of ptsH had little effect on the above-mentioned factors. Although co-overexpression of ptsGHI led to the highest glucose consumption, growth rate, and final l-lysine production; the l-lysine production rate was lower than that of XQ-8sugR::cat/pDXW-8-ptsIH. In fed-batch fermentation, XQ-8sugR::cat/pDXW-8-ptsIH had a higher growth rate of 0.54 h −1 to a dry cell mass of 66 g·L −1 after 16 h, and had a higher l-lysine production rate of 159.2 g·L −1 after 36 h. These results indicate that modification of the sugar transport systems improves amino acid production, especially for mutants obtained by repeated physical and (or) chemical mutagenesis. However, modification of these systems needs to be performed on a case-by-case basis.
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 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".