title: Unique communities of anoxygenic phototrophic bacteria in saline lakes of Salar de Atacama (Chile): evidence for a new phylogenetic lineage of phototrophic Gammaproteobacteria from pufLM gene analyses.
abstract: Phototrophic bacteria are important primary producers of salt lakes in the Salar de Atacama and at times form visible mass developments within and on top of the lake sediments. The communities of phototrophic bacteria from two of these lakes were characterized by molecular genetic approaches using key genes for the biosynthesis of the photosynthetic apparatus in phototrophic purple bacteria (pufLM) and in green sulfur bacteria (fmoA). Terminal restriction fragment length polymorphism of the pufLM genes indicated high variability of the community composition between the two lakes and subsamples thereof. The communities were characterized by the dominance of a novel, so far undescribed lineage of pufLM containing bacteria and the presence of representatives related to known halophilic Chromatiaceae and Ectothiorhodospiraceae. In addition, the presence of BChl b-containing anoxygenic phototrophic bacteria and of aerobic anoxygenic bacteria was indicated. Green sulfur bacteria were not detected in the environmental samples, although a bacterium related to Prosthecochloris indicum was identified in an enrichment culture. This is the first comprehensive description of phototrophic bacterial communities in a salt lake of South America made possible only due to the application of the functional pufLM genes.
authors.affiliation: Leibniz-Institut für Meereswissenschaften (IFM-GEOMAR), Kiel, Germany.
authors.forename: Vera
authors.initials: V
authors.lastname: Thiel
authors.forename: Marcus
authors.initials: M
authors.lastname: Tank
authors.forename: Sven C
authors.initials: SC
authors.lastname: Neulinger
authors.forename: Linda
authors.initials: L
authors.lastname: Gehrmann
authors.forename: Cristina
authors.initials: C
authors.lastname: Dorador
authors.forename: Johannes F
authors.initials: JF
authors.lastname: Imhoff
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics; D002677:Chile; D002841:Chromatiaceae / Q000145:classification / Q000235:genetics; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000235:genetics; D042001:Ectothiorhodospiraceae / Q000145:classification / Q000235:genetics; D020563:Gammaproteobacteria / Q000145:classification / Q000235:genetics*; D005798:Genes, Bacterial; D045342:Light-Harvesting Protein Complexes / Q000235:genetics; D010788:Photosynthesis; D045322:Photosynthetic Reaction Center Complex Proteins / Q000235:genetics; D052817:Phototrophic Processes; D010802:Phylogeny; D012150:Polymorphism, Restriction Fragment Length; D054712:Salinity; D014871:Water Microbiology
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D045342:Light-Harvesting Protein Complexes; D045322:Photosynthetic Reaction Center Complex Proteins; C096433:PufL protein, Bacteria; C098543:PufM protein, Bacteria