DNA from lake sediments reveals the long-term dynamics and diversity of Synechococcus assemblages

Autor: Domaizon, Isabelle, Savichtcheva, O., Debroas, D., Arnaud, F., VILLARD, Claude, Pignol, C., Alric, Benjamin, Perga, Marie-Elodie
Přispěvatelé: Centre Alpin de Recherche sur les Réseaux Trophiques et Ecosystèmes Limniques (CARRTEL), Institut National de la Recherche Agronomique (INRA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), Laboratoire Microorganismes : Génome et Environnement (LMGE), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Université d'Auvergne - Clermont-Ferrand I (UdA)-Centre National de la Recherche Scientifique (CNRS), Environnements, Dynamiques et Territoires de Montagne (EDYTEM), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), French National Research Agency (France) [ANR VULNS-005], INEE (CNRS France), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de la Recherche Agronomique (INRA), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Centre National de la Recherche Scientifique (CNRS)-Université d'Auvergne - Clermont-Ferrand I (UdA), Environnements, Dynamiques et Territoires de la Montagne (EDYTEM)
Jazyk: angličtina
Rok vydání: 2013
Předmět:
Zdroj: Biogeosciences
Biogeosciences, 2013, 10 (10), p. 3817-3838. ⟨10.5194/bg-10-3817-2013⟩
Biogeosciences, Vol 10, Iss 6, Pp 3817-3838 (2013)
Biogeosciences, European Geosciences Union, 2013, p. 3817-3838. ⟨10.5194/bg-10-3817-2013⟩
Biogeosciences, European Geosciences Union, 2013, 10 (10), p. 3817-3838. ⟨10.5194/bg-10-3817-2013⟩
Biogeosciences 6 (10), 3817-3838. (2013)
ISSN: 1726-4170
1726-4189
DOI: 10.5194/bg-10-3817-2013⟩
Popis: While picocyanobacteria (PC) are important actors in carbon and nutrient cycles in aquatic systems, factors controlling their interannual dynamics and diversity are poorly known due to the general lack of long-term monitoring surveys. This study intended to fill this gap by applying a DNA-based paleolimnological approach to sediment records from a deep subalpine lake that has experienced dramatic changes in environmental conditions during the last century (eutrophication, re-oligotrophication and large-scale climate changes). In particular, we investigated the long-term (100 yr) diversity and dynamics of Synechococcus,, PC that have presumably been affected by both the lake trophic status changes and global warming. The lake's morphological and environmental conditions provided the ideal conditions for DNA preservation in the sediment archives. Generalised additive models applied to quantitative PCR (qPCR; quantitative Polymerase Chain Reaction) results highlighted that an increase in summer temperature could have a significant positive impact on the relative abundance of Synechococcus, (fraction of Synechococcus, in total cyanobacteria). The diversity of Synechococcus, in Lake Bourget was studied by phylogenetic analyses of the 16S rRNA gene and the following internally transcribed spacer (ITS). Up to 23 different OTUs (based on 16S rRNA), which fell into various cosmopolitan or endemic clusters, were identified in samples from the past 100 yr. Moreover, the study of ITS revealed a higher diversity within the major 16S rRNA-defined OTUs. Changes in PC diversity were related to the lake's trophic status. Overall, qPCR and sequencing results showed that environmental changes (in temperature and phosphorus concentration) affected Synechococcus, community dynamics and structure, translating into changes in genotype composition. These results also helped to re-evaluate the geographical distribution of some Synechococcus, clusters. Providing such novel insights into the long-term history of an important group of primary producers, this study illustrates the promising approach that consists in coupling molecular tools and paleolimnology to reconstruct a lake's biodiversity history.
Databáze: OpenAIRE
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