Structure of pteridine reductase (PTR1) from<i>Leishmania tarentolae</i>
Bibliographic record
Abstract
The protozoan parasites Leishmania utilize a pteridine-reducing enzyme, pteridine reductase (PTR1), to bypass antifolate inhibition. The crystal structure of PTR1 from L. tarentolae has been solved as a binary complex with NADPH at 2.8 A resolution. The structure was solved by molecular-replacement techniques using the recently reported L. major PTR1 structure as a search model. Comparisons of the present structure with the L. major PTR1 allowed us to identify regions of flexibility in the molecule. PTR1 is a member of the growing family of short-chain dehydrogenases (SDR) which share the characteristic Tyr(Xaa)(3)Lys motif in the vicinity of the active site. The functional enzyme is a tetramer and the crystallographic asymmetric unit contains a tetramer with 222 point-group symmetry.
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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 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.001 | 0.003 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.002 | 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".