Solution Characterization and Initial Crystallization Studies of TrbB from the F Plasmi
Bibliographic record
Abstract
Secretion systems, found across gram-negative and gram-positive bacteria, are large multi-protein complexes responsible for the transport of genetic material and proteins across phospholipid membranes, with dedicated systems in place for the secretion of virulence factors into host cells or the environment. One such pathway can be found in Gram-negative bacteria bearing conjugative F-like plasmids is known as the Type IV Secretion System (T4SSF). This system comprises multiple proteins responsible for cell proliferation, transport of virulence factors and antibiotic resistance genes through bacterial conjugation. Bacterial conjugation involves the assembly of a transmembrane conjugative pili for Gram negative bacteria bearing F-like plasmids, that is responsible for plasmid DNA transfer. TrbB is a periplasmic protein encoded by the F- plasmid transfer region (tra), with disulfide isomerase and reductase activity. TrbB is proposed to be involved in the assembly of the F-pilus and aid in protein folding for other T4SSF proteins. Previous studies of full-length TrbB indicated a dynamic N-terminal domain likely responsible for protein-protein interactions. In the current study, we present recent SEC-MALS-SAXS data and initial high-throughput crystallization trials of an N- terminally truncated TrbB construct (TrbB37-161). SAXS data indicates several species in solution (monomer, dimer, tetramer), and crystallization trials identify several promising leads for further optimization. Noting the important role of conjugation in the the spread of antibiotic resistance genes and TrbB’s role in assembly of the conjugative F-pilus, further structural investigation may lead to improved strategies for curtailing the spread of antibiotic resistant pathogens with multidrug resistance
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) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 0.001 |
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".