Scheda di dettaglio – i prodotti della ricerca
| Dato | Valore |
|---|---|
| Title | Phylogenetic diversity of non-marine picocyanobacteria |
| Abstract | The most updated picture of the 16S rRNA phylogenetic tree of picocyanobacteria, including marine and freshwater strains, confirms the indication that Synechococcus 5.3 is not included in Synechococcus 5.1 but is its sister clade. The non-marine picocyanobacteria are considered as closely related to Cyanobium strains and proposed as monophyletic "Cyanobium-like" lineage. Nevertheless the relationships of these lineages to one another remain ambiguous. From this comes the need to enlarge the database with new sequences of isolated Synechococcus strains from a wider range of locations and environments to obtain a more realistic view of Synechococcus genus dispersal and evolution. In this study we aimed to resolve better the Synechococcus phylogenetic tree enlarging the sequence data set of non-marine picocyanobacteria including strains isolated from "extreme" lakes. Therefore we selected four high altitude athalassohaline maar crater-lakes in Mexico as a source for "non-marine halotolerant" Synechococcus, five glacial ultraoligotrophic North Patagonian lakes as extreme ecosystems, and six Italian lakes of glacial, volcanic and morenic origin, with different trophic conditions. Our objective was to create a new phylogenetic tree of non-marine Synechococcus upgraded adding 43 new sequences derived from isolated picocyanobacteria and to refine the taxonomic relationships between non-marine Synechococcus clades and Synechococcus 5.2 and 5.3. The new sequences fall into a number of both novel and previously described clades within the phylogenetic tree of 16S rRNA gene. The new cluster of Lake Nahuel Huapi (North Patagonia) forms a sister clade to the subalpine cluster II and the marine Synechococcus sub-cluster 5.2. Our finding of the novel clade of "Halotolerants" close to the marine sub-cluster 5.3 (Synechococcus RCC307) constitutes an important demonstration that euryhaline and marine strains affiliate closely. The intriguing results obtained shed new light on the importance of the non-marine halotolerants in the phylogenesis of picocyanobacteria. |
| Source | SAME13: EMBO Conference on Aquatic Microbial Ecology, Stresa (VB), 8-13 settembre 2013 |
| Keywords | Phylogenetic treeSynechococcusHalotolerant |
| Year | 2013 |
| Type | Poster |
| Authors | Cristiana Callieri; Manuela Coci; Gianluca Corno; Miroslav Macek; Beatriz Modenutti; Esteban Balseiro; Roberto Bertoni |
| Text | 282590 2013 Phylogenetic tree Synechococcus Halotolerant Phylogenetic diversity of non marine picocyanobacteria Cristiana Callieri; Manuela Coci; Gianluca Corno; Miroslav Macek; Beatriz Modenutti; Esteban Balseiro; Roberto Bertoni Cristiana Callieri; Manuela Coci; Gianluca Corno; Roberto Bertoni CNR ISE VB Miroslav Macek FES Iztacala, Department of Tropical Limnology, UNAM, Mexico Beatriz Modenutti; Esteban Balseiro UNC Laboratory of Limnology, CONICET, Bariloche, Argentina The most updated picture of the 16S rRNA phylogenetic tree of picocyanobacteria, including marine and freshwater strains, confirms the indication that Synechococcus 5.3 is not included in Synechococcus 5.1 but is its sister clade. The non marine picocyanobacteria are considered as closely related to Cyanobium strains and proposed as monophyletic Cyanobium like lineage. Nevertheless the relationships of these lineages to one another remain ambiguous. From this comes the need to enlarge the database with new sequences of isolated Synechococcus strains from a wider range of locations and environments to obtain a more realistic view of Synechococcus genus dispersal and evolution. In this study we aimed to resolve better the Synechococcus phylogenetic tree enlarging the sequence data set of non marine picocyanobacteria including strains isolated from extreme lakes. Therefore we selected four high altitude athalassohaline maar crater lakes in Mexico as a source for non marine halotolerant Synechococcus, five glacial ultraoligotrophic North Patagonian lakes as extreme ecosystems, and six Italian lakes of glacial, volcanic and morenic origin, with different trophic conditions. Our objective was to create a new phylogenetic tree of non marine Synechococcus upgraded adding 43 new sequences derived from isolated picocyanobacteria and to refine the taxonomic relationships between non marine Synechococcus clades and Synechococcus 5.2 and 5.3. The new sequences fall into a number of both novel and previously described clades within the phylogenetic tree of 16S rRNA gene. The new cluster of Lake Nahuel Huapi North Patagonia forms a sister clade to the subalpine cluster II and the marine Synechococcus sub cluster 5.2. Our finding of the novel clade of Halotolerants close to the marine sub cluster 5.3 Synechococcus RCC307 constitutes an important demonstration that euryhaline and marine strains affiliate closely. The intriguing results obtained shed new light on the importance of the non marine halotolerants in the phylogenesis of picocyanobacteria. Published version In SAME13 I EMBO Conference on Aquatic Microbial Ecology Stresa VB , 8 13 settembre 2013 . SAME13 EMBO Conference on Aquatic Microbial Ecology Stresa VB 8 13 settembre 2013 Internazionale Contributo Poster Poster_Same13.pdf Poster roberto.bertoni BERTONI ROBERTO manuela.coci COCI MANUELA cristiana.callieri CALLIERI CRISTIANA gianluca.corno CORNO GIANLUCA TA.P04.016.004 Ecologia teorica e applicata degli ecosistemi acquatici |