title: Bacterial Diversity in Microbial Mats and Sediments from the Atacama Desert.
abstract: The Atacama Desert has extreme environmental conditions that allow the development of unique microbial communities. The present paper reports the bacterial diversity of microbial mats and sediments and its mineralogical components. Some physicochemical conditions of the water surrounding these ecosystems have also been studied trying to determine their influence on the diversity of these communities. In that way, mats and sediments distributed among different hypersaline lakes located in salt flats of the Atacama Desert were subjected to massive parallel sequencing of the V4 region of the 16S rRNA genes of Bacteria. A higher diversity in sediment than in mat samples have been found. Lakes that harbor microbial mats have higher salinity than lakes where mats are absent. Proteobacteria and/or Bacteroidetes are the major phyla represented in all samples. An interesting item is the finding of a low proportion or absence of Cyanobacteria sequences in the ecosystems studied, suggesting the possibility that other groups may be playing an essential role as primary producers in these extreme environments. Additionally, the large proportion of 16S rRNA gene sequences that could not be classified at the level of phylum indicates potential new phyla present in these ecosystems.
authors.affiliation: Laboratorio de Investigaciones Microbiológicas de Lagunas Andinas (LIMLA), Planta Piloto de Procesos Industriales Microbiológicos (PROIMI), CCT, CONICET, Tucumán, Argentina.
authors.forename: Maria Cecilia
authors.initials: MC
authors.lastname: Rasuk
authors.affiliation: Laboratorio de Investigaciones Microbiológicas de Lagunas Andinas (LIMLA), Planta Piloto de Procesos Industriales Microbiológicos (PROIMI), CCT, CONICET, Tucumán, Argentina.
authors.forename: Ana Beatriz
authors.initials: AB
authors.lastname: Fernández
authors.affiliation: Laboratorio de Investigaciones Microbiológicas de Lagunas Andinas (LIMLA), Planta Piloto de Procesos Industriales Microbiológicos (PROIMI), CCT, CONICET, Tucumán, Argentina.
authors.forename: Daniel
authors.initials: D
authors.lastname: Kurth
authors.affiliation: Centro de Ecología Aplicada (CEA), Suecia 3304, Ñuñoa, Santiago, F 56-2-2741872, Chile.
authors.forename: Manuel
authors.initials: M
authors.lastname: Contreras
authors.affiliation: Centro de Ecología Aplicada (CEA), Suecia 3304, Ñuñoa, Santiago, F 56-2-2741872, Chile.
authors.forename: Fernando
authors.initials: F
authors.lastname: Novoa
authors.affiliation: Centro de Investigaciones Geológicas, Universidad Nacional de La Plata-Conicet, calle 1 no 644, 1900, La Plata, Argentina.
authors.forename: Daniel
authors.initials: D
authors.lastname: Poiré
authors.affiliation: Laboratorio de Investigaciones Microbiológicas de Lagunas Andinas (LIMLA), Planta Piloto de Procesos Industriales Microbiológicos (PROIMI), CCT, CONICET, Tucumán, Argentina. mefarias@proimi.org.ar.
authors.forename: María Eugenia
authors.initials: ME
authors.lastname: Farías
mesh_terms: D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification*; D044822:Biodiversity; D004269:DNA, Bacterial / Q000235:genetics; D003889:Desert Climate; D019015:Geologic Sediments / Q000382:microbiology*; D060106:Lakes / Q000032:analysis / Q000382:microbiology*; D008969:Molecular Sequence Data; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics
chemical_list: D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S
keywords: Atacama Desert; Hypersaline lakes; Mats; Microbial diversity; Sediments