Undecompressed microbial populations from the deep sea

Retrieval of concentrated and undecompressed microbial populations from the deep sea.

A device for sampling at depths of up to 6,000 m is described in which 3 liters of seawater is concentrated over a Nucleopore filter to about 13 ml and retrieved under in situ pressure and temperature. Subsamples can be withdrawn into transfer units that are equipped with individual gas accumulators for preventing loss of pressure during prolonged periods of storage. Transfer of samples or samp...

Microbial activities in undecompressed and decompressed deep-seawater samples.

Microbial transformations of C-labeled substrates (sodium glutamate, Casamino Acids, glucose, and sodium acetate) were measured in undecompressed seawater samples collected from depths of 1,800 to 6,000 m, during 14- to 21-day incubation periods at in situ temperature (3 degrees C). Each substrate was tested at two concentrations (ca. 0.5 and 5.0 mug/ml) and two in situ pressures. The data were...

Comparison of Thaumarchaeotal populations from four deep sea basins

The nitrogen cycle in the marine environment is strongly affected by ammonia-oxidizing Thaumarchaeota. In some marine settings, Thaumarchaeotes can comprise a large percentage of the prokaryotic population. To better understand the biogeographic patterns of Thaumarchaeotes, we sought to investigate differences in their abundance and phylogenetic diversity between geographically distinct basins....

Climate Influence on Deep Sea Populations

Dynamics of biological processes on the deep-sea floor are traditionally thought to be controlled by vertical sinking of particles from the euphotic zone at a seasonal scale. However, little is known about the influence of lateral particle transport from continental margins to deep-sea ecosystems. To address this question, we report here how the formation of dense shelf waters and their subsequ...

Piezophiles: Microbial Adaptation to the Deep-sea Environment