RT Journal Article SR Electronic T1 Diversity and Distribution of Sulfate-Reducing Bacteria in Permanently Frozen Lake Fryxell, McMurdo Dry Valleys, Antarctica JF Applied and Environmental Microbiology JO Appl. Environ. Microbiol. FD American Society for Microbiology SP 6353 OP 6359 DO 10.1128/AEM.71.10.6353-6359.2005 VO 71 IS 10 A1 Karr, Elizabeth A. A1 Sattley, W. Matthew A1 Rice, Melissa R. A1 Jung, Deborah O. A1 Madigan, Michael T. A1 Achenbach, Laurie A. YR 2005 UL http://aem.asm.org/content/71/10/6353.abstract AB The permanently frozen freshwater Lake Fryxell, located in the Dry Valleys of Antarctica, exhibits an ideal geochemistry for microbial sulfate reduction. To investigate the population of sulfate-reducing bacteria in Lake Fryxell, both 16S rRNA gene and metabolic primer sets targeting the dsrA gene for the dissimilatory sulfite reductase alpha subunit were employed to analyze environmental DNA obtained from the water column and sediments of Lake Fryxell. In addition, enrichment cultures of sulfate-reducing bacteria established at 4°C from Lake Fryxell water were also screened using the dsrA primer set. The sequence information obtained showed that a diverse group of sulfate-reducing prokaryotes of the domain Bacteria inhabit Lake Fryxell. With one exception, the enrichment culture sequences were not represented within the environmental sequences. Sequence data were compared with the geochemical profile of Lake Fryxell to identify possible connections between the diversity of sulfate-reducing bacteria and limnological conditions. Several clone groups were highly localized with respect to lake depth and, therefore, experienced specific physiochemical conditions. However, all sulfate-reducing bacteria inhabiting Lake Fryxell must function under the constantly cold conditions characteristic of this extreme environment.