Prevention of Peptide Fibril Formation in an Aqueous Environment by Mutation of a Single Residue to Aib
Bibliographic record
Abstract
The behavior of a number of 16 residue polypeptides with a sequence Acetyl-EACARXZAACEAAARQ-amide, where X = V or A and Z = A or Aib, is studied under aqueous conditions. It is shown that the substitution of a single alanine residue by alpha-aminoisobutyric acid (Aib) completely alters both the conformation and the aggregation properties of the peptides. The Ala-Ala (X,Z = A,A) peptide is shown by circular dichroism and FTIR methods to adopt a predominately beta-sheet conformation. Furthermore, the peptide has limited solubility and is shown to form fibrils by electron microscopy and thioflavin T binding assays. In contrast, a single substitution at the center of peptide of alanine to Aib (X,Z = A,Aib) completely abolishes fibril formation and alters the conformation to a mixture of random coil and alpha-helix. The results show that Aib is a strong beta-sheet disrupter that is also able to adopt a helical conformation. This is linked to its role in peptaibol antibiotics. Aib provides an attractive alternative to proline and other substitutions in producing peptide variants with a lower tendency to produce fibril aggregates.
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".