Inorganic carbon acquisition and its energization in eustigmatophyte algae
Bibliographic record
Abstract
The eustigmatophyceans are primitive unicellular algae that represent the most basal group of ochrophytes. They are believed to be obligate photoautotrophs, occurring mainly in freshwater and soil but with some marine representatives. The freshwater eustigmatophytes Monodus subterraneus and Vischeria stellata , and the marine eustigmatophyte Nannochloropsis gaditana , have been studied by mass spectrometry with respect to their characteristics for inorganic carbon (Ci) uptake. A CO2 concentrating mechanism was found in all three, but an external carbonic anhydrase (CA) was not detected. The acquisition of Ci from the external medium was based on the active transport of HCO3–, CO2, or both. In particular, N. gaditana was able to use HCO3– exclusively as an exogenous carbon source for photosynthesis, with this HCO3– being subsequently converted to CO2 by an intracellular CA for photosynthetic fixation. A unique characteristic of this species was its capacity to transport HCO3– during prolonged periods of time in the dark. In contrast, M. subterraneus utilized CO2 alone through an active transport process, whereas V. stellata exhibited the capacity to transport both HCO3– and CO2. The uptake of CO2 also continued in the dark in V. stellata cells. Regardless of the Ci species taken up, transport was abolished by anoxia and by inhibitors of mitochondrial respiration. These results indicate that that the supply of Ci for photosynthetic CO2 fixation is partly dependent upon mitochondrial activity in these primitive eukaryotes.
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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) | 0.001 | 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".