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This dataset contains measurements of microbial mat thickness and number of laminae from Lake Fryxell, McMurdo Dry Valleys, Antarctica. Holes were melted through the ice cover of Lake Fryxell, which allowed tethered divers to collect benthic microbial mats (non-liftoff and liftoff) and microbial mats at the ice-water interface (float mats). Benthic non-liftoff and liftoff mat samples were collected from 4.3 m (n=4), 6.1 m (n=4), and 7.9 m (n=4) depths. Float mats were collected from the ice-water interface above 4.3 m (n=4), 6.1 m (n=4), and 7.9 m (n=5) depths. The mats were dissected along vertical cross sections in the field to measure mat thickness and number of laminae. Additional funding for this work was provided by the NASA Solar System Workings Program (Award #80NSSC22K0709).
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Antibiotic resistance genes and taxa analysis from mat and planktonic microbiomes of Antarctic perennial ice-covered Lake Fryxell and Lake Bonney
Abstract The perennial ice-covered lakes of the Antarctic McMurdo Dry Valleys harbour oligotrophic microbial communities that are separated geographically from other aquatic systems. Their microbiomes include planktonic microbes as well as lift-off mat communities that emerge from the ice. We used the ShortBRED protein family profiler to quantify the antibiotic resistance genes (ARGs) from metagenomes of lift-off mats emerging from ice and from filtered water samples of Lake Fryxell and Lake Bonney. The overall proportion of ARG hits was similar to that found in temperate-zone rural ponds with moderate human inputs. Specific ARGs showed distinct distributions for the two lakes and for mat vs planktonic sources. Metagenomic taxa distributions showed that mat phototrophs consisted mainly of cyanobacteria or Betaproteobacteria, whereas the water column phototrophs were mainly protists. An enrichment culture of the Betaproteobacterium Rhodoferax antarcticus from a Lake Fryxell mat sample showed an unusual mat-forming phenotype not previously reported for this species. Its genome showed no ARGs associated with Betaproteobacteria but had ARGs consistent with a minor Pseudomonas component. The Antarctic lake mats and water showed specific ARGs distinctive to the mat and water sources, but overall ARG levels were similar to those of temperate water bodies with moderate human inputs.
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- Award ID(s):
- 1923077
- PAR ID:
- 10425685
- Date Published:
- Journal Name:
- Antarctic Science
- Volume:
- 34
- Issue:
- 6
- ISSN:
- 0954-1020
- Page Range / eLocation ID:
- 408 to 422
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1017/S0954102022000360
