title: Phylogenetic Profiling and Diversity of Bacterial Communities in the Death Valley, an Extreme Habitat in the Atacama Desert.
abstract: The Atacama Desert, one of the driest deserts in the world, represents a unique extreme environmental ecosystem to explore the bacterial diversity as it is considered to be at the dry limit for life. A 16S rRNA gene (spanning the hyper variable V3 region) library was constructed from an alkaline sample of unvegetated soil at the hyperarid margin in the Atacama Desert. A total of 244 clone sequences were used for MOTHUR analysis, which revealed 20 unique phylotypes or operational taxonomic units (OTUs). V3 region amplicons of the 16S rRNA were suitable for distinguishing the bacterial community to the genus and specie level. We found that all OTUs were affiliated with taxa representative of the Firmicutes phylum. The extremely high abundance of Firmicutes indicated that most bacteria in the soil were spore-forming survivors. In this study we detected a narrower diversity as compared to other ecological studies performed in other areas of the Atacama Desert. The reported genera were Oceanobacillus (representing the 69.5 % of the clones sequenced), Bacillus, Thalassobacillus and Virgibacillus. The present work shows physical and chemical parameters have a prominent impact on the microbial community structure. It constitutes an example of the communities adapted to live in extreme conditions caused by dryness and metal concentrations .
authors.affiliation: Department of Genetics and Evolution (DGE), UFSCar, Via Washington Luis, Km. 235, São Carlos, SP Brazil ; Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Seville, C/Profesor García González, 2, 41012 Seville, Spain.
authors.forename: Francine
authors.initials: F
authors.lastname: Piubeli
authors.affiliation: Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Seville, C/Profesor García González, 2, 41012 Seville, Spain.
authors.forename: María
authors.initials: M
authors.lastname: de Lourdes Moreno
authors.affiliation: Department of Genetics and Evolution (DGE), UFSCar, Via Washington Luis, Km. 235, São Carlos, SP Brazil.
authors.forename: Luciano Takeshi
authors.initials: LT
authors.lastname: Kishi
authors.affiliation: Department of Genetics and Evolution (DGE), UFSCar, Via Washington Luis, Km. 235, São Carlos, SP Brazil.
authors.forename: Flavio
authors.initials: F
authors.lastname: Henrique-Silva
authors.affiliation: Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Seville, C/Profesor García González, 2, 41012 Seville, Spain.
authors.forename: María Teresa
authors.initials: MT
authors.lastname: García
authors.affiliation: Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Seville, C/Profesor García González, 2, 41012 Seville, Spain.
authors.forename: Encarnación
authors.initials: E
authors.lastname: Mellado
keywords: 16S rDNA; Atacama Desert; Bacteria; Extreme habitat; Extremophiles