Genetic Adaptations Are Key To Microbe's Survival In Challenging Environment

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 February 6 in the open-access journal PLoS Genetics.



The research focused on the bacterium Nautilia profundicola, a microbe that survives near deep-sea hydrothermal vents. Photosynthesis cannot occur in
this dark environment, where hot, toxic fluids oozing from below the seafloor combine with cold seawater at very high pressures.



The study, involving scientists at the University of Delaware, the Davis and Riverside campuses of the University of California, the Universities of
Louisville, KY, and Waikato, New Zealand, and the J. Craig Venter Institute, combined genome analysis with physiological and ecological observations
to investigate the importance of one gene in N. profundicola. Previous studies found the gene only in microorganisms growing in temperatures greater
than 80oC, but N. profundicola thrives best at much lower temperatures. The gene's presence in N. profundicola suggests that it might play a role in
the bacterium's ability to survive rapid and frequent temperature fluctuations in its environment.



The researchers also uncovered further adaptations to the vent environment, including genes necessary for growth and sensing environmental conditions,
and a new route for nitrate assimilation related to how other bacteria use ammonia as an energy source.



These results help to explain how microbes survive near deep-sea hydrothermal vents, where conditions are thought to resemble those found on early
Earth, as described in the study. Improved understanding of microbes living in these conditions may aid our understanding of how life evolved here.



CITATION: "Adaptations to Submarine Hydrothermal Environments Exemplified by the
Genome of Nautilia profundicola."
Campbell BJ, Smith JL, Hanson TE, Klotz MG, Stein LY, et al. (2009)
PLoS Genet 5(2): e1000362. doi:10.1371/journal.pgen.1000362

Click here to view article online.




About PLoS Genetics



PLoS Genetics reflects the full breadth and interdisciplinary nature of genetics and genomics research by publishing
outstanding original contributions in all areas of biology. All works published in PLoS Genetics are open access. Everything is immediately and freely
available online throughout the world subject only to the condition that the original authorship and source are properly attributed. Copyright is
retained by the authors. The Public Library of Science uses the Creative Commons Attribution License.

PLoS Genetics



About the Public Library of Science



The Public Library of Science (PLoS) is a non-profit organization of scientists and physicians committed to making the world's scientific and medical
literature a freely available public resource.

Public Library of Science