A multidomain hydrolase from the thermophile <i>Thermanaeromonas toyohensis</i> degrades high molecular mass forms of polyhydroxybutyrate
Bibliographic record
Abstract
The use of polyhydroxybutyrate (PHB) bioplastics has the potential to create a circular and sustainable recycling plastic system. Here, we focus on PHB degradation and characterize the multidomain PHB hydrolyzing enzyme from the extremophile Thermanaeromonas tohohensis. The catalytic domain fold is conserved across a diverse taxonomic range, but the C-terminal domains are unique amongst PHBases and instead share similarities with carbohydrate degrading enzymes from human gut microbiota. The enzyme has a preference for higher molecular weight PHB. Hydrolysis of PHB films correlates with the ability of the enzyme to bind those films, most likely driven by its C-terminal substrate binding domain. The enzyme denatures in a highly cooperative manner over a short temperature range, and the kinetics of folding/unfolding are well described by Eyring theory. Finally, the study of this enzyme has been incorporated into an undergraduate biochemistry teaching laboratory that focuses on "real life" research problems with relevance to industry.
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) | 0.000 | 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 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".