Microbial communities in the subglacial waters of the Vatnajokull ice cap, Iceland Journal Article

Authors: Marteinsson, Viggo Thor; Runarsson, Arni; Stefansson, Andri; Thorsteinsson, Thorsteinn; Johannesson, Tomas; Magnusson, Sveinn H.; Reynisson, Eyjolfur; Einarsson, Bergur; Wade, Nicole; Morrison, Hilary G.; Gaidos, Eric
Article Title: Microbial communities in the subglacial waters of the Vatnajokull ice cap, Iceland
Abstract: Subglacial lakes beneath the Vatnajokull ice cap in Iceland host endemic communities of microorganisms adapted to cold, dark and nutrient-poor waters, but the mechanisms by which these microbes disseminate under the ice and colonize these lakes are unknown. We present new data on this subglacial microbiome generated from samples of two subglacial lakes, a subglacial flood and a lake that was formerly subglacial but now partly exposed to the atmosphere. These data include parallel 16S rRNA gene amplicon libraries constructed using novel primers that span the v3-v5 and v4-v6 hypervariable regions. Archaea were not detected in either subglacial lake, and the communities are dominated by only five bacterial taxa. Our paired libraries are highly concordant for the most abundant taxa, but estimates of diversity (abundance-based coverage estimator) in the v4-v6 libraries are 3-8 times higher than in corresponding v3-v5 libraries. The dominant taxa are closely related to cultivated anaerobes and microaerobes, and may occupy unique metabolic niches in a chemoautolithotrophic ecosystem. The populations of the major taxa in the subglacial lakes are indistinguishable (gt;99% sequence identity), despite separation by 6 km and an ice divide; one taxon is ubiquitous in our Vatnajokull samples. We propose that the glacial bed is connected through an aquifer in the underlying permeable basalt, and these subglacial lakes are colonized from a deeper, subterranean microbiome. The ISME Journal (2013) 7, 427-437; doi:10.1038/ismej.2012.97; published online 13 September 2012
Keywords: DIVERSITY; SEQUENCE; GEN. NOV.; LAKE; Deep-sea; SP-NOV.; RARE BIOSPHERE; SUBSURFACE; astrobiology; subglacial lakes; SULFATE-REDUCING BACTERIUM; Pyrosequencing; acetogenesis; extreme environments; psychrophiles; OIL STORAGE CAVITY
Journal Title: ISME Journal
Volume: 7
Issue: 2
ISSN: 1751-7362
Publisher: Nature Publishing Group  
Date Published: 2013
Start Page: 427
End Page: 437
Notes: PT: J; TC: 0; UT: WOS:000316723300019