Multiple Campylobacter jejuni proteins affecting the peptidoglycan structure and the degree of helical cell curvature
Bibliographic record
Abstract
Campylobacter jejuni is a Gram-negative helical bacterium. Its helical morphology, maintained by the peptidoglycan (PG) layer, plays a key role in its transmission in the environment, colonization, and pathogenic properties. The previously characterized PG hydrolases Pgp1 and Pgp2 are important for generating C. jejuni helical morphology, with deletion mutants being rod-shaped and showing alterations in their PG muropeptide profiles in comparison to the wild type. Homology searches and bioinformatics were used to identify additional gene products involved in C. jejuni morphogenesis: the putative bactofilin 1104 and the M23 peptidase domain-containing proteins 0166, 1105, and 1228. Deletions in the corresponding genes resulted in varying curved rod morphologies with changes in their PG muropeptide profiles. All changes in the mutants complemented except 1104. Overexpression of 1104 and 1105 also resulted in changes in the morphology and in the muropeptide profiles, suggesting that the dose of these two gene products influences these characteristics. The related helical ε-Proteobacterium Helicobacter pylori has characterized homologs of C. jejuni 1104, 1105, and 1228 proteins, yet deletion of the homologous genes in H. pylori had differing effects on H. pylori PG muropeptide profiles and/or morphology compared to the C. jejuni deletion mutants. It is therefore apparent that even related organisms with similar morphologies and homologous proteins can have diverse PG biosynthetic pathways, highlighting the importance of studying PG biosynthesis in related organisms.
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 | 0.000 |
| 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 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".