title: 16S rRNA and As-Related Functional Diversity: Contrasting Fingerprints in Arsenic-Rich Sediments from an Acid Mine Drainage.
abstract: To gain an in-depth insight into the diversity and the distribution of genes under the particular evolutionary pressure of an arsenic-rich acid mine drainage (AMD), the genes involved in bacterial arsenic detoxification (arsB, ACR3) and arsenite oxidation (aioA) were investigated in sediment from Carnoulès (France), in parallel to the diversity and global distribution of the metabolically active bacteria. The metabolically active bacteria were affiliated mainly to AMD specialists, i.e., organisms detected in or isolated from AMDs throughout the world. They included mainly Acidobacteria and the non-affiliated "Candidatus Fodinabacter communificans," as well as Thiomonas and Acidithiobacillus spp., Actinobacteria, and unclassified Gammaproteobacteria. The distribution range of these organisms suggested that they show niche conservatism. Sixteen types of deduced protein sequences of arsenite transporters (5 ArsB and 11 Acr3p) were detected, whereas a single type of arsenite oxidase (AioA) was found. Our data suggested that at Carnoulès, the aioA gene was more recent than those encoding arsenite transporters and subjected to a different molecular evolution. In contrast to the 16S ribosomal RNA (16S rRNA) genes associated with AMD environments worldwide, the functional genes aioA, ACR3, and to a lesser extent arsB, were either novel or specific to Carnoulès, raising the question as to whether these functional genes are specific to high concentrations of arsenic, AMD-specific, or site-specific.
authors.affiliation: Équipe Environnement et Microbiologie, EEM, UMR 5254 (IPREM, CNRS), Université de Pau et des Pays de l'Adour, IBEAS, BP 1155, 64013, Pau Cedex, France.
authors.forename: Anne
authors.initials: A
authors.lastname: Fahy
authors.forename: Ludovic
authors.initials: L
authors.lastname: Giloteaux
authors.forename: Philippe
authors.initials: P
authors.lastname: Bertin
authors.forename: Denis
authors.initials: D
authors.lastname: Le Paslier
authors.forename: Claudine
authors.initials: C
authors.lastname: Médigue
authors.forename: Jean
authors.initials: J
authors.lastname: Weissenbach
authors.forename: Robert
authors.initials: R
authors.lastname: Duran
authors.forename: Béatrice
authors.initials: B
authors.lastname: Lauga
mesh_terms: D061271:Acidobacteria / Q000235:genetics*; D001151:Arsenic / Q000032:analysis*; D053501:Arsenite Transporting ATPases / Q000235:genetics; D001483:Base Sequence; D044822:Biodiversity; D003001:Cloning, Molecular; D017931:DNA Primers / Q000235:genetics; D005602:France; D008906:Mining; D008969:Molecular Sequence Data; D010088:Oxidoreductases / Q000235:genetics; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000032:analysis*
chemical_list: D017931:DNA Primers; D012336:RNA, Ribosomal, 16S; D012989:Soil Pollutants; D010088:Oxidoreductases; C078179:arsenite oxidase; D053501:Arsenite Transporting ATPases; D001151:Arsenic