Retracted: Isocratic Method for Affinity Enrichment of Covalently‐linked Peptides in Cyanogen Bromide Cleavage of Proteins
Post-publication record
Source: Retraction Watch, joined by DOI. OpenAlex records retraction as is_retracted, a boolean over a state space with at least four values, so it cannot express an expression of concern, a correction or a reinstatement; it reports them as false, which reads as “fine”.
Bibliographic record
Abstract
The low resolution three-dimensional structure of a protein can be inferred from existing disulfide bridges or experimentally introduced chemical crosslinks. The general procedure involves enzymatic digestion of a protein followed by mass spectrometry-based identification of covalently-linked peptides, native disulfide-linked peptides and chemically cross-linked peptides. To facilitate unambiguous identification of these peptides, an isocratic purification method was developed for selective enrichment of covalently-linked cyanogen bromide (CNBr) fragments. This method capitalizes on the ability of homoserine lactone moieties at the C-termini of CNBr cleavage products for selective conjugation of primary-amine containing affinity tag. The availability of two C-termini within covalently-linked peptides allows for the conjugation of two affinity tags, whereas the other peptides have only one affinity tag at the C-terminus, which enables selective enrichment of covalently-linked peptides by utilization of affinity tag with moderate dissociation constant. Here we demonstrate successful implementation of this method with tetrahistidine as the affinity tag for enrichment of covalently-linked CNBr fragments of test peptides and proteins.
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 | 0.002 | 0.002 |
| Meta-epidemiology (narrow) | 0.002 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.002 | 0.001 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.004 | 0.001 |
| Research integrity | 0.002 | 0.004 |
| Insufficient payload (model declined to judge) | 0.007 | 0.011 |
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".