Design and implementation of a transmitter-receiver genetic circuit
Notice bibliographique
Résumé
Summary form only given. A prototype of a transmitter-receiver genetic circuit was designed and constructed. This design allows the transmission of signals between Gram-positive bacteria (Streptococcus mutans) and Gram-negative bacteria (Vibrio harveyi). AutoInducer-2 (AI-2) is used as the signaling molecule. For the transmitter circuit, we created a plasmid that contained a luxS gene (responsible for AI-2 synthesis) and an inducible promoter. This plasmid was inserted into S. mutans to form the transmitter cells. The transmitter activity can be modulated. Glucose lowers luxS gene expression, thus reducing AI-2 production. Raffinose activates the promoter, leading to an increase in AI-2 production. The receiver detects the signal produced by the transmitter. Vibrio harveyi BB170 was used as the receiver. This strain of bacteria lacks the gene to produce AI-2, but it has the receptor for AI-2 detection. When the bacteria detect AI-2, they produce luciferase, leading to light production. The circuit was tested by examining the luxS gene expression in the transmitter cells and the luminescence level of the receiver cells. First, the luxS gene expression of the transmitter was investigated. The transmitter cells were cultured with a supplement of either glucose (i.e. transmitter "off") or raffinose ("on") until they reached mid-log phase. The luxS expression levels in the activated cells were 10-fold higher than those in the repressed cells. The impact of different sugars (glucose and raffinose) on cell growth was examined. The measured doubling time for the cells in each of raffinose and glucose was 63.76plusmn0.30 and 67.59plusmn0.34 minutes, respectively. The similarity of the doubling times suggested that the sugars had no effect on normal cell growth. The behaviour of the receiver was then investigated. The receiver cells were exposed to the supernatant of the transmitter cells to test their AI-2 detection capability. The supernatant of mid-log phase transmitter cells was collected by removing the cells through centrifugation followed by filtration. The luminescence level of the receivers was measured hourly for five hours. A five-fold luminescence signal increase was observed after four hours of incubation with the supernatant. The underlying mechanism of this delay in the receiver response time is unclear. A computational approach was used to investigate the cause of the delay. A stochastic model of the receiver cells was developed based on Gillespie's algorithm. Our simulation yielded a receiver response time of just less than two hours. This is the first study on synthetic interspecies communication. The ability to communicate between species will be a valuable tool for the creation of larger engineered systems
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,001 | 0,000 |
| Science ouverte | 0,001 | 0,000 |
| Intégrité de la recherche | 0,001 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,004 | 0,001 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».