Dataset Information

Microbial analysis of Zetaproteobacteria and co-colonizers of iron mats in the Troll Wall Vent Field, Arctic Mid-Ocean Ridge.

ABSTRACT: Over the last decade it has become increasingly clear that Zetaproteobacteria are widespread in hydrothermal systems and that they contribute to the biogeochemical cycling of iron in these environments. However, how chemical factors control the distribution of Zetaproteobacteria and their co-occurring taxa remains elusive. Here we analysed iron mats from the Troll Wall Vent Field (TWVF) located at the Arctic Mid-Ocean Ridge (AMOR) in the Norwegian-Greenland Sea. The samples were taken at increasing distances from high-temperature venting chimneys towards areas with ultraslow low-temperature venting, encompassing a large variety in geochemical settings. Electron microscopy revealed the presence of biogenic iron stalks in all samples. Using 16S rRNA gene sequence profiling we found that relative abundances of Zetaproteobacteria in the iron mats varied from 0.2 to 37.9%. Biogeographic analyses of Zetaproteobacteria, using the ZetaHunter software, revealed the presence of ZetaOtus 1, 2 and 9, supporting the view that they are cosmopolitan. Relative abundances of co-occurring taxa, including Thaumarchaeota, Euryarchaeota and Proteobacteria, also varied substantially. From our results, combined with results from previous microbiological and geochemical analyses of the TWVF, we infer that the distribution of Zetaproteobacteria is connected to fluid-flow patterns and, ultimately, variations in chemical energy landscapes. Moreover, we provide evidence for iron-oxidizing members of Gallionellaceae being widespread in TWVF iron mats, albeit at low relative abundances.

SUBMITTER: Vander Roost J

PROVIDER: S-EPMC5607188 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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Microbial analysis of Zetaproteobacteria and co-colonizers of iron mats in the Troll Wall Vent Field, Arctic Mid-Ocean Ridge.

Vander Roost Jan J Thorseth Ingunn Hindenes IH Dahle Håkon H

PloS one 20170920 9

Over the last decade it has become increasingly clear that Zetaproteobacteria are widespread in hydrothermal systems and that they contribute to the biogeochemical cycling of iron in these environments. However, how chemical factors control the distribution of Zetaproteobacteria and their co-occurring taxa remains elusive. Here we analysed iron mats from the Troll Wall Vent Field (TWVF) located at the Arctic Mid-Ocean Ridge (AMOR) in the Norwegian-Greenland Sea. The samples were taken at increas ...[more]

PMID: 28931087

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Dataset Information

Microbial analysis of Zetaproteobacteria and co-colonizers of iron mats in the Troll Wall Vent Field, Arctic Mid-Ocean Ridge.

Publications

Microbial analysis of Zetaproteobacteria and co-colonizers of iron mats in the Troll Wall Vent Field, Arctic Mid-Ocean Ridge.

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