The ecology, physiology, and diversity of aerobic anoxygenic phototrophs in Lake Winnipeg, Canada
Notice bibliographique
Résumé
Aerobic anoxygenic phototrophs (AAP) are a group of photoheterotrophic bacteria that use sunlight as a supplemental energy source, allowing them to be found in many illuminated environments. Here, we investigated their presence in Lake Winnipeg, Manitoba, Canada with spatial and temporal considerations to define the niche that they fill, and understand the biogeochemical pathways influenced or controlled by AAP. In addition, we explored their diversity and expanded upon the range of photosynthetic arrangements known, by looking into a variety of newly purified pigmented isolates to assess unique characteristics, all of which allowed us to better understand the AAP group as a whole. We described seasonal trends of microbial communities in Lake Winnipeg, where up to 1.49% of the sequenced community and 19.1% of the total culturable copiotrophic heterotrophs were AAP at littoral zones during their peak spring season, and they directly followed sunlight availability. Isolated and purified strains were capable of several metal transformations, including metal(loid) oxide reduction and production of siderophores or metallophores. This widespread physiology, particularly among lake isolates, suggested a potential ecological importance for AAP involving a metal(loid) collecting niche. AAP with elongated cells were established as both associated to, and possibly preyed upon by filter feeding mollusks Dreissena polymorpha, which provided insights into how these bacteria interact with the foodweb. Many pigmented and phylogenetically diverse strains were discovered from across the lakes euphotic zones. Representatives of each different species were physiologically, morphologically and phylogenetically compared and described, showing members of specific taxonomic families all shared heritable traits including pigments. This confirmed evolutionary age of photosynthesis in AAP, and suggested recent horizontal gene transfer events did not occur. Furthermore, unusual aerobic violet pigmented strains that came from under the frozen surface during winter were explored. Overall, the study of Lake Winnipeg microbial communities led to several important discoveries: Seasonal dynamics found that AAP followed daylight trends rather than any other environmental parameter; These phototrophs were likely preyed upon by filter feeding mollusks; Several new metal transformation capabilities were described; Unique pigmentation was found. All combined considerations confirmed the importance of AAP as regular members of this freshwater ecosystem, with high numbers and large diversity, likely contributing significantly to the foodweb.
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) | 0,001 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,002 | 0,003 |
| Études des sciences et des technologies | 0,003 | 0,001 |
| Communication savante | 0,001 | 0,000 |
| Science ouverte | 0,001 | 0,001 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,001 | 0,000 |
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 ».