Karl Stetter

Last updated
Karl Stetter
Karl Stetter.jpg
Stetter in 2010
Born
Karl Otto Stetter

16 July 1941
Alma mater Technical University of Munich
Known forDiscovering new archaea
Awards Leeuwenhoek Medal

Karl Otto Stetter (born 16 July 1941) is a German microbiologist and authority on astrobiology. Stetter is an expert on microbial life at high temperatures.

Contents

Career

Stetter was born in Munich and studied biology at the Technical University of Munich. Stetter wrote Stetter's doctoral dissertation on lactobacilli. From 1980 to 2002 Stetter was professor at, and head of, the department of microbiology and of the Archaea center of the University of Regensburg.

The majority of Stetter's research has focused on sampling, isolating and characterizing archaeal organisms which comprise the third domain of life, particularly undiscovered extremely heat-loving ( hyperthermophilic ) bacteria and Archaea, also called extremophiles, growing optimally between 80 and 113 °C.

Major discovery

In 1992, Stetter, along with Robert Huber, discovered a new species of thermophilic bacteria near Kolbeinsey Ridge and named the species Aquifex pyrophilous . [1]

Nanoarchaeum equitans, an archaeal microorganism containing the world's smallest known genome, was discovered by Stetter in 2002 in a hydrothermal vent off the coast of Iceland. This archaebacterium was described in the scientific journal Nature in May 2002. [2]

Discoveries

Among the other extremophiles discovered by Stetter has been Pyrococcus furiosus , [3] which was found on the Italian island of Vulcano in 1981. This extremophile was the source of Pfu DNA polymerase. Stetter also discovered Aquifex aeolicus and Aquifex pyrophilus .

Awards and memberships

In 2003, Stetter was honored with the Leeuwenhoek Medal by the Royal Netherlands Academy of Arts and Sciences, an award given every 10 years to the scientist who has made the most outstanding contributions to the advancement of microbiology.

Stetter is a member of the:

See also

Related Research Articles

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<span class="mw-page-title-main">Nanoarchaeota</span> Phylum of archaea

Nanoarchaeota is a proposed phylum in the domain Archaea that currently has only one representative, Nanoarchaeum equitans, which was discovered in a submarine hydrothermal vent and first described in 2002.

The Aquificota phylum is a diverse collection of bacteria that live in harsh environmental settings. The name Aquificota was given to this phylum based on an early genus identified within this group, Aquifex, which is able to produce water by oxidizing hydrogen. They have been found in springs, pools, and oceans. They are autotrophs, and are the primary carbon fixers in their environments. These bacteria are Gram-negative, non-spore-forming rods. They are true bacteria as opposed to the other inhabitants of extreme environments, the Archaea.

A hyperthermophile is an organism that thrives in extremely hot environments—from 60 °C (140 °F) upwards. An optimal temperature for the existence of hyperthermophiles is often above 80 °C (176 °F). Hyperthermophiles are often within the domain Archaea, although some bacteria are also able to tolerate extreme temperatures. Some of these bacteria are able to live at temperatures greater than 100 °C, deep in the ocean where high pressures increase the boiling point of water. Many hyperthermophiles are also able to withstand other environmental extremes, such as high acidity or high radiation levels. Hyperthermophiles are a subset of extremophiles. Their existence may support the possibility of extraterrestrial life, showing that life can thrive in environmental extremes.

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"Aquifex aeolicus" is a chemolithoautotrophic, Gram-negative, motile, hyperthermophilic bacterium. "A. aeolicus" is generally rod-shaped with an approximate length of 2.0-6.0μm and a diameter of 0.4-0.5μm. "A. aeolicus" is neither validly nor effectively published and, having no standing in nomenclature, should be styled in quotation marks. It is one of a handful of species in the Aquificota phylum, an unusual group of thermophilic bacteria that are thought to be some of the oldest species of bacteria, related to filamentous bacteria first observed at the turn of the century. "A. aeolicus" is also believed to be one of the earliest diverging species of thermophilic bacteria. "A. aeolicus" grows best in water between 85 °C and 95 °C, and can be found near underwater volcanoes or hot springs. It requires oxygen to survive but has been found to grow optimally under microaerophilic conditions. Due to its high stability against high temperature and lack of oxygen, "A. aeolicus" is a good candidate for biotechnological applications as it is believed to have potential to be used as hydrogenases in an attractive H2/O2 biofuel cell, replacing chemical catalysts. This can be useful for improving industrial processes.

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<span class="mw-page-title-main">Archaea</span> Domain of single-celled organisms

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The Kolbeinsey Ridge is a segment of the Mid-Atlantic Ridge located to the north of Iceland in the Arctic Ocean. It is bounded to the south by the Tjörnes Fracture Zone, which connects the submarine ridge to the on-shore Northern Volcanic Zone rifting center in eastern Iceland. The volcanic islands Kolbeinsey and Grímsey lie along the Kolbeinsey Ridge.

References

  1. O., Huber, Robert. Stetter, Karl (1992). Aquifex pyrophilus gen. nov. sp. nov., represents a novel group of marine hyperthermophilic hydrogen-oxidizing bacteria. Fischer. OCLC   750884111.{{cite book}}: CS1 maint: multiple names: authors list (link)
  2. Huber, H; Hohn, MJ; Rachel, R; Fuchs, T; Wimmer, VC; Stetter, KO (2 May 2002). "A new phylum of Archaea represented by a nanosized hyperthermophilic symbiont". Nature. 417 (6884): 63–7. Bibcode:2002Natur.417...63H. doi:10.1038/417063a. PMID   11986665. S2CID   4395094.
  3. Fiala, Gerhard; Stetter, Karl O. (June 1986). "Pyrococcus furiosus sp. nov. represents a novel genus of marine heterotrophic archaebacteria growing optimally at 100°C". Archives of Microbiology. 145 (1): 56–61. doi:10.1007/BF00413027. S2CID   41589578.
  4. "K.O. Stetter". Royal Netherlands Academy of Arts and Sciences . Retrieved 17 July 2015.