title: Acidicapsa ferrireducens sp. nov., Acidicapsa acidiphila sp. nov., and Granulicella acidiphila sp. nov.: novel acidobacteria isolated from metal-rich acidic waters.
abstract: Four novel strains of Acidobacteria were isolated from water samples taken from pit lakes at two abandoned metal mines in the Iberian Pyrite Belt mining district, south-west Spain. Three of the isolates belong to the genus Acidicapsa (MCF9T, MCF10T, and MCF14) and one of them to the genus Granulicella (MCF40T). All isolates are moderately acidophilic (pH growth optimum 3.8-4.1) and mesophilic (temperature growth optima 30-32 °C). Isolates MCF10Tand MCF40Tgrew at pH lower (<3.0) than previously reported for all other acidobacteria. All four strains are obligate heterotrophs and metabolised a wide range of sugars. While all four isolates are obligate aerobes, MCF9T, MCF10T, and MCF14 catalysed the reductive dissolution of the ferric iron mineral schwertmannite when incubated under micro-aerobic conditions. Isolates MCF9Tand MCF14 shared 99.5% similarity of their 16 S rRNA genes, and were considered to be strains of the same species. The major quinone of strains MCF10T, MCF9T, and MCF40Tis MK-8, and their DNA G + C contents are 60.0, 59.7, and 62.1 mol%, respectively. Based on phylogenetic and phenotypic data, three novel species, Acidicapsa ferrireducens strain MCF9T(=DSM 28997T= NCCB 100575T), Acidicapsa acidiphila strain MCF10T(=DSM 29819T= NCCB 100576T), and Granulicella acidiphila strain MCF40T(DSM 28996T= NCCB 100577T), are proposed.
authors.affiliation: College of Natural Sciences, Bangor University, Deiniol Road, Bangor, LL57 2UW, UK. c.falagan@bangor.ac.uk.
authors.forename: Carmen
authors.initials: C
authors.lastname: Falagán
authors.affiliation: Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Inhoffenstrasse 7B, 38124, Brunswick, Germany.
authors.forename: Bärbel
authors.initials: B
authors.lastname: Foesel
authors.affiliation: College of Natural Sciences, Bangor University, Deiniol Road, Bangor, LL57 2UW, UK.
authors.forename: Barrie
authors.initials: B
authors.lastname: Johnson
mesh_terms: D061271:Acidobacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D001482:Base Composition; D007501:Iron / Q000032:analysis / Q000378:metabolism*; D060106:Lakes / Q000737:chemistry / Q000382:microbiology; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D014871:Water Microbiology
chemical_list: D012336:RNA, Ribosomal, 16S; D007501:Iron
keywords: Acidobacteria; Acidophile; Iron reduction; Metal-tolerance; Pit lakes