Dark Anaerobic Hydrogen Production in the Mutants of Synechocystis sp. Strain PCC6803-GT Defective in Lactate Dehydrogenase Activity and/or Alcohol Dehydrogenase Activity, Incubated in Buffer Solutions With or Without Glucose
Bibliographic record
Abstract
To redirect NAD(P)H consumed by dehydrogenases to NiFe-hydrogenase, the genes encoding for lactate dehydrogenase (ddh) and alcohol dehydrogenase (adh) were disrupted in a glucose tolerant mutant of unicellular cyanobacterium Synechocystis sp. strain PCC6803 (GT strain). The cells of GT strain, ddh deficient (Dddh) mutant and both adh and ddh deficient (DadhDddh) mutant were harvested at the late-logarithmic growth phase of photoautotrophic culture in antibiotic-free BG-11 medium. Dark anaerobic hydrogen production in GT strain, Dddh mutant and DadhDddh mutant in nitrate-free HEPES buffer solution without or with glucose has been studied by following the time courses of the number of moles of hydrogen, endogenous and exogenous glucose, lactate, acetate and ethanol per culture volume and the dry cell weight concentration. Dark incubation of cells of Dddh mutant and DadhDddh mutant in HEPES buffer solution without glucose resulted 1.16-fold and 1.15-fold increases in the initial hydrogen production rates over GT strain, respectively, while 1.1-fold and 0.85-fold increases in the number of moles of hydrogen per culture volume at 96 h over GT strain, respectively. When hydrogen production experiments were performed in the glucose-added HEPES buffer solution, dark incubation of cells of Dddh mutant and DadhDddh mutant resulted 1.4-fold and 1.6-fold increases in the initial hydrogen production rates over GT strain without glucose run, respectively, while 1.5-fold and 1.3-fold increases in the number of moles of hydrogen per culture volume at 96 h over GT strain without glucose run, respectively.
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 | 0.000 |
| 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 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".