For next weeks #microtwjc session (8pm BST 23rd July) I thought we would cool things down a little and discuss sequencing bacteria and eukarya in ice taken from a lake in Antarctica. The paper was recently published in PLOS one and is available from the following link http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0067221

Abstract:
Lake Vostok, the 7th largest (by volume) and 4th deepest lake on Earth, is covered by more than 3,700 m of ice, making it the
largest subglacial lake known. The combination of cold, heat (from possible hydrothermal activity), pressure (from the
overriding glacier), limited nutrients and complete darkness presents extreme challenges to life. Here, we report
metagenomic/metatranscriptomic sequence analyses from four accretion ice sections from the Vostok 5G ice core. Two
sections accreted in the vicinity of an embayment on the southwestern end of the lake, and the other two represented part
of the southern main basin. We obtained 3,507 unique gene sequences from concentrates of 500 ml of 0.22 mm-filtered
accretion ice meltwater. Taxonomic classifications (to genus and/or species) were possible for 1,623 of the sequences.
Species determinations in combination with mRNA gene sequence results allowed deduction of the metabolic pathways
represented in the accretion ice and, by extension, in the lake. Approximately 94% of the sequences were from Bacteria and
6% were from Eukarya. Only two sequences were from Archaea. In general, the taxa were similar to organisms previously
described from lakes, brackish water, marine environments, soil, glaciers, ice, lake sediments, deep-sea sediments, deep-sea
thermal vents, animals and plants. Sequences from aerobic, anaerobic, psychrophilic, thermophilic, halophilic, alkaliphilic,
acidophilic, desiccation-resistant, autotrophic and heterotrophic organisms were present, including a number from
multicellular eukaryotes.

Discussion points:

1. Was the paper well written, easy to understand/follow and the data presented well?

2. Were the methods appropriate? Anything else you would have liked the authors to do?

3. Are the results useful? Do they help us to understand microbial communities?

4. What next?

Advertisements