Feb. 17, 2009 The genome of a marine bacterium living 2,500
meters below the ocean's surface is providing clues to how life
adapts in extreme thermal and chemical gradients, according to
an article published Feb. 6 in the journal PLoS Genetics. The
research focused on the bacterium Nautilia profundicola, a
microbe that survives near deep-sea hydrothermal vents.
Microorganisms that thrive at these geysers on the sea floor
must adapt to fluctuations in temperature and oxygen levels,
ranging from the hot, sulfide- and heavy metal-laden plume at
the vents' outlets to cold seawater in the surrounding region.
The study combined genome analysis with physiological and
ecological observations to investigate the importance of one
gene in N. profundicola. That gene, called rgy, allows the
bacterium to manufacture a protein called reverse gyrase when it
encounters extremely hot fluids from the Earth's interior.
Previous studies found the gene only in microorganisms growing
in temperatures greater than 80°C, but N. profun