Mechanism of Hydrogen Peroxide Production by Copper-Bound Amyloid Beta Peptide: A Theoretical Study
Bibliographic record
Abstract
The amyloid beta peptide (Abeta) of Alzheimer's disease evolves hydrogen peroxide in vitro in the presence of Cu(II), external reducing agents, and molecular oxygen, without producing detectable amounts of the one-electron reduced intermediate, superoxide, O(2)(-*). The mechanism of this process was examined by ab initio computational chemistry techniques in systems that model the binding of Cu(II) to the His13His14 fragment of Abeta. The catalytic cycle begins with the reduction of the most stable Cu(II) complex to the most stable Cu(I) complex. This Cu(I) complex forms a Cu(II)-like adduct with (3)O(2) that cannot dissociate in water to yield O(2)(-*). However, it can be reduced by proton-coupled electron transfer to an adduct between HOO(-) and the Cu(II)-like complex, which in turn can be protonated. The protonated complex decomposes to yield H(2)O(2) by an associative-dissociative mechanism, thus completing the cycle.
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 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.002 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.005 | 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".