In:
Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences, Vol. 97, No. 3 ( 2000-02), p. 1247-1251
Abstract:
Microbes, some of which may be viable, have been found in ice cores
drilled at Vostok Station at depths down to ≈3,600 m, close to the surface of the huge subglacial Lake Vostok. Two types of ice have been
found. The upper 3,500 m comprises glacial ice containing traces of nutrients of aeolian origin including sulfuric acid, nitric acid,
methanosulfonic acid (MSA), formic acid, sea salts, and mineral grains. Ice below ≈3,500 m comprises refrozen water from Lake Vostok,
accreted to the bottom of the glacial ice. Nutrients in the accretion ice include salts and dissolved organic carbon. There is great interest
in searching for living microbes and especially for new species in deepest Antarctic ice. I propose a habitat consisting of interconnected
liquid veins along three-grain boundaries in ice in which psychrophilic bacteria can move and obtain energy and carbon from ions in solution.
In the accretion ice, with an age of a few 10 4 years and a
temperature a few degrees below freezing, the carbon and energy sources in the veins can maintain significant numbers of cells per cubic
centimeter that are metabolizing but not multiplying. In the 4 × 10 5 -year-old colder glacial ice, at least 1 cell per
cm 3 in acid veins can be maintained. With fluorescence
microscopy tuned to detect NADH in live organisms, motile bacteria could be detected by direct scanning of the veins in ice samples.
Type of Medium:
Online Resource
ISSN:
0027-8424
,
1091-6490
DOI:
10.1073/pnas.97.3.1247
Language:
English
Publisher:
Proceedings of the National Academy of Sciences
Publication Date:
2000
detail.hit.zdb_id:
209104-5
detail.hit.zdb_id:
1461794-8
SSG:
11
SSG:
12
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