Nitrogen Fixation at 92°C by a Hydrothermal Vent Archaeon

  title={Nitrogen Fixation at 92°C by a Hydrothermal Vent Archaeon},
  author={Mausmi P. Mehta and John A. Baross},
  pages={1783 - 1786}
A methanogenic archaeon isolated from deep-sea hydrothermal vent fluid was found to reduce N2 to NH3 at up to 92°C, which is 28°C higher than the current upper temperature limit of biological nitrogen fixation. The 16S ribosomal RNA gene of the hyperthermophilic nitrogen fixer, designated FS406-22, was 99% similar to that of non–nitrogen fixing Methanocaldococcus jannaschii DSM 2661. At its optimal growth temperature of 90°C, FS406-22 incorporated 15N2 and expressed nifH messenger RNA. This… 
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  • Environmental Science
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Temporal Changes in Archaeal Diversity and Chemistry in a Mid-Ocean Ridge Subseafloor Habitat
The temperature and chemical indicators of the degree of subseafloor mixing appear to be the most important environmental parameters affecting community diversity, and it is apparent that decreasing fluid temperatures correlated with increased entrainment of seaw water, decreased concentrations of hydrothermal chemical species, and increased incidence of seawater archaeal sequences.
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    Proceedings of the National Academy of Sciences of the United States of America
  • 2001
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