title: Bacterial diversity in dry modern freshwater stromatolites from Ruidera Pools Natural Park, Spain.
abstract: Ruidera Pools Natural Park, Spain, constitutes one of the most representative systems of carbonate precipitation in Europe. The prokaryotic community of a dry modern stromatolite recovered from the park has been analyzed by molecular techniques that included denaturing gradient gel electrophoresis (DGGE) and 16S rRNA gene clone library analysis, together with microscopic observations from the sample and cultures. Ribosomal RNA was directly extracted to study the putatively active part of the microbial community present in the sample. A total of 295 16S rRNA gene sequences were analyzed. Libraries were dominated by sequences related to Cyanobacteria, most frequently to the genus Leptolyngbya. A diverse and abundant assemblage of non-cyanobacterial sequences was also found, including members of Firmicutes, Bacteroidetes, Proteobacteria, Actinobacteria, Acidobacteria,Planctomycetes and Chloroflexi groups. No amplification was obtained when using archaeal primers. The results showed that at the time of sampling, when the pool was dry, the bacterial community of the stromatolites was dominated by groups of highly related Cyanobacteria, including new groups that had not been previously reported, although a high diversity outside this phylogenetic group was also found. The results indicated that part of the Cyanobacteria assemblage was metabolically active and could thus play a role in the mineralization processes inside the stromatolites.
authors.affiliation: División de Microbiología, Departamento de Fisiología, Genética y Microbiología, Universidad de Alicante, 03080 Alicante, Spain.
authors.forename: Fernando
authors.initials: F
authors.lastname: Santos
authors.forename: Arantxa
authors.initials: A
authors.lastname: Peña
authors.forename: Balbina
authors.initials: B
authors.lastname: Nogales
authors.forename: Elena
authors.initials: E
authors.lastname: Soria-Soria
authors.forename: M Angeles García
authors.initials: MA
authors.lastname: Del Cura
authors.forename: Juan Antonio
authors.initials: JA
authors.lastname: González-Martín
authors.forename: Josefa
authors.initials: J
authors.lastname: Antón
mesh_terms: D001419:Bacteria / Q000145:classification* / Q000254:growth & development*; D044822:Biodiversity; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel; D054892:Metagenome; D008853:Microscopy; D008969:Molecular Sequence Data; D009691:Nucleic Acid Denaturation; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology; D013030:Spain
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S