Pyrolobus fumarii Amy McCann
Thermophilic microorganisms are unique cells that are endowed with the capability of growth at elevated temperatures. Although the upper temperature limit for life may not yet have been ascertained, we do know that certain hyperthermophilic archaebacteria can proliferate at 110°C in ocean depths where water remains liquid at this temperature. Thermophilic representatives are found among the algae, fungi, protozoa, cyanobacteria, eubacteria, and archaebacteria. These organisms inhabit a variety of ecological niches including thermal soils, desert sands, hot springs, solfataric fields, submarine hydrotherrnal systems, waters surrounding boiling outflows from geothermal power plants, and smoldering coal refuse piles.
Pyrolobus fumarii, or "fire lobe of the chimney," was named for its lobed shape and for where it was discovered - in the walls of a hydrothermal vent known as a "black smoker". He grows at temperatures between 90 and 113°C (the hottest temperature yet associated with any living creature) with 106°C being optimal. . P. fumarii is also quite resistant to temperatures above this range. He can survive autoclaving for one hour! While that exceeds the boiling point of water at sea level, it is far below boiling in the intense pressures exerted at its home depth of 3600 meters. The organism requires no organic matter - it grows on a substrate of hydrogen (a liquid at deep-sea pressures) and is nourished by nitrate, small amounts of oxygen, or sulfate. This microbe adds to evidence that the ingredients for life can be pretty simple. Along with water, as long as you have some kind of energy source like hydrogen that can be produced geochemically, you have all the elements necessary for life. Also, the new microbe expands the possibility of life on other planets.
Morphology: lobed coccus
Metabolism: chemolithotrophic H2 oxidation coupled to reduction of N03-to NH4+
Oxygen needs: Facultative
GC content: 53 mol %
Temp. range: 90 - 113°C
Optimum pH: 5.5
*Disclaimer - This report was written by a student participaring in a microbiology course at the Missouri University of Science and Technology. The accuracy of the contents of this report is not guaranteed and it is recommended that you seek additional sources of information to verify the contents.
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