A common pathway for <i><scp>O</scp></i>‐linked protein‐glycosylation and synthesis of capsule in <i><scp>A</scp>cinetobacter baumannii</i>
Bibliographic record
Abstract
Multi-drug resistant strains of Acinetobacter baumannii are increasingly being isolated in hospitals worldwide. Among the virulence factors identified in this bacterium there is a general O-glycosylation system that appears to be important for biofilm formation and virulence, and the capsular polysaccharide, which is essential for resistance to complement killing. In this work, we identified a locus that is responsible for the synthesis of the O-pentasaccharide found on the glycoproteins. Besides the enzymes required for the assembly of the glycan, additional proteins typically involved in polymerization and transport of capsule were identified within or adjacently to the locus. Mutagenesis of PglC, the initiating glycosyltransferase prevented the synthesis of both glycoproteins and capsule, resulting in abnormal biofilm structures and attenuated virulence in mice. These results, together with the structural analysis of A. baumannii 17978 capsular polysaccharide via NMR, demonstrated that the pentasaccharides that decorate the glycoproteins are also the building blocks for capsule biosynthesis. Two linked subunits, but not longer glycan chains, were detected on proteins via MS. The discovery of a bifurcated pathway for O-glycosylation and capsule synthesis not only provides insight into the biology of A. baumannii but also identifies potential novel candidates for intervention against this emerging pathogen.
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 | 0.001 | 0.001 |
| 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".