Isolation ofSphaerotilus-Leptothrixstrains from iron bacteria communities in Tierra del Fuego wetlands

Abstract

Sheath-forming iron- and manganese-depositing bacteria belonging to the Sphaerotilus-Leptothrix group (SLG) are widespread in natural and artificial water systems. Known requirements for their growth include the presence of organic substrates and molecular oxygen. High concentrations of reduced iron or manganese, although not necessary for most species, make their growth a noticeable phenomenon. Such microbial communities have been studied mostly in the Northern Hemisphere. Here, we present descriptions of diverse ochre-depositing microbial communities in Tierra del Fuego, Argentina, using a combined approach of microscopical examination, clone library construction and cultivation focused on SLG bacteria. To date, only few SLG type strains are available. The present work increases the number and diversity of cultivated SLG bacteria by obtaining isolates from biofilms and sediment samples of wetlands in Tierra del Fuego. Thirty isolates were selected based on morphological features such as sheath formation and iron/manganese deposition. Five operational taxonomic units (OTUs) were deduced. Sequencing of 16S rRNA genes showed that one OTU is identical to the Leptothrix mobilis Feox-1(T) -sequence while the four remaining OTUs show similarity values related to previously described type strains. Similarity values ranged from 96.5% to 98.8%, indicating possible new species and subspecies.

Complete Genome Sequence of “ Candidatus Viadribacter manganicus” Isolated from a German Floodplain Area

“…After an incubation time of up to 2 weeks at room temperature, we selected dark brown colonies that formed on the agar surface. Iron- and manganese-deposition of the strain was confirmed using the methods of Schmidt et al (4). EDX mapping of colonies suggested that manganese and iron were predominantly concentrated outside the bacteria cells.…”

Draft Genome Sequence of Ideonella sp. Strain A 288, Isolated from an Iron-Precipitating Biofilm

“…Strain A 288, which originated from an iron and manganese-depositing biofilm of the Lower Oder Valley National Park, was isolated and cultivated as described elsewhere ( 8 ). The iron-depositing ability of the strain, which formed dark, brown-colored colonies on iron- and manganese-containing media, was confirmed according to Schmidt et al ( 8 ). Genomic DNA was extracted using the GeneMATRIX soil DNA purification kit (Roboklon, Berlin, Germany).…”

Draft Genome Sequence of Strain R_RK_3, an Iron-Depositing Isolate of the Genus Rhodomicrobium , Isolated from a Dewatering Well of an Opencast Mine

“…Sequential dilutions of sampled ochrous material were spread on modified Leptothrix medium ( 10 ) (deionized water was replaced by sterile well water), and reddish-brown colonies were selected after incubation for 17 to 21 days at room temperature. The iron- and manganese-depositing activity of the isolate was verified by dissolving the colonies with oxalic acid (10%) as previously described by Schmidt et al ( 11 ). Strain R_RK_3 is a small Gram-negative bacterium with a coccus shape of 2- to 4-µm length and a width of 1.0 µm.…”