Subcellular location of phage infection protein (Pip) in <i>Lactococcus lactis</i>
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
The amino acid sequence of the phage infection protein (Pip) of Lactococcus lactis predicts a multiple-membrane-spanning region, suggesting that Pip may be anchored to the plasma membrane. However, a near-consensus sortase recognition site and a cell wall anchoring motif may also be present near the carboxy terminus. If functional, this recognition site could lead to covalent linkage of Pip to the cell wall. Pip was detected in both plasma membranes and envelopes (plasma membrane plus peptidoglycan) isolated from the wild-type Pip strain LM2301. Pip was firmly attached to membrane and envelope preparations and was solubilized only by treatment with detergent. Three mutant Pip proteins were separately made in which the multiple-membrane-spanning region was deleted (Pip-Deltammsr), the sortase recognition site was converted to the consensus (Pip-H841G), or the sortase recognition site was deleted (Pip-Delta6). All three mutant Pip proteins co-purified with membranes and could not be solubilized except with detergent. When membranes containing Pip-Deltammsr were sonicated and re-isolated by sucrose density gradient centrifugation, Pip-Deltammsr remained associated with the membranes. Strains that expressed Pip-H841G or Pip-Delta6 formed plaques with near unit efficiency, whereas the strain that expressed Pip-Deltammsr did not form plaques of phage c2. Both membranes and cell-free culture supernatant from the strain expressing Pip-Deltammsr inactivated phage c2. These results suggest that Pip is an integral membrane protein that is not anchored to the cell wall and that the multiple-membrane-spanning region is required for productive phage infection but not phage inactivation.
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.
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 it