Microorganism: Difference between revisions

[[Extremophiles]] are microorganisms that have adapted so that they can survive and even thrive in [[extreme environment]]s that are normally fatal to most life-forms. [[Thermophile]]s and [[hyperthermophiles]] thrive in high [[temperature]]s. [[Psychrophile]]s thrive in extremely low temperatures. – Temperatures as high as {{convert|130|°C|°F}},<ref>[[Strain 121]], a [[Hyperthermophile|hyperthermophilic]] [[archaea]], has been shown to reproduce at {{convert|121|°C|°F}}, and survive at {{convert|130|°C|°F}}.[https://www.nsf.gov/od/lpa/news/03/pr0384.htm]</ref> as low as {{convert|-17|°C|°F}}<ref>Some [[Psychrophiles|Psychrophilic]] bacteria can grow at {{convert|-17|°C|°F}}),[http://news.bbc.co.uk/1/hi/sci/tech/827063.stm] and can survive near [[absolute zero]]).{{cite web |title=Earth microbes on the Moon |url=https://science.nasa.gov/newhome/headlines/ast01sep98_1.htm |url-status=dead |archive-url=https://web.archive.org/web/20100323224432/http://science.nasa.gov/newhome/headlines/ast01sep98_1.htm |archive-date=23 March 2010 |access-date=2009-07-20}}</ref> [[Halophile]]s such as ''[[Halobacterium salinarum]]'' (an archaean) thrive in high [[Salinity|salt conditions]], up to saturation.<ref>Dyall-Smith, Mike, [http://www.microbiol.unimelb.edu.au/people/dyallsmith/ ''HALOARCHAEA''], University of Melbourne. See also [[Haloarchaea]].</ref> [[Alkaliphile]]s thrive in an [[alkaline]] [[pH]] of about 8.5–11.<ref>{{Cite journal|url=http://jb.asm.org/cgi/reprint/185/2/461.pdf|title=''Bacillus alcalophilus'' can grow at up to pH 11.5|journal=Journal of Bacteriology|date=15 January 2003|volume=185|issue=2|pages=461–465|doi=10.1128/JB.185.2.461-465.2003|last1=Olsson|first1=Karen|last2=Keis|first2=Stefanie|last3=Morgan|first3=Hugh W.|last4=Dimroth|first4=Peter|last5=Cook|first5=Gregory M.|pmid=12511491|pmc=145327}}</ref> [[Acidophile]]s can thrive in a pH of 2.0 or less.<ref>[[Picrophilus]] can grow at pH −0.06.[http://www.rcn.montana.edu/resources/organisms/organisminfo.aspx?nav=11&tid=1298&did=1&nid=82076&lid=9] {{Webarchive|url=https://web.archive.org/web/20100622184325/http://www.rcn.montana.edu/resources/organisms/organisminfo.aspx?nav=11&tid=1298&did=1&nid=82076&lid=9|date=22 June 2010}}</ref> [[Piezophile]]s thrive at very [[high pressure]]s: up to 1,000–2,000 [[Atmosphere (unit)|atm]], down to 0 atm as in a [[vacuum]] of [[Outer space|space]].{{efn|The [[Piezophile|piezophilic]] bacteria [[Halomonas salaria]] requires a pressure of 1,000 atm; [[nanobes]], a speculative organism, have been reportedly found in the earth's crust at 2,000 atm.<ref>{{cite web | url=http://www.microscopy-uk.org.uk/index.html?http://www.microscopy-uk.org.uk/nanobes/nanopaper.html | title=Microscopy-UK Home (Resources for the microscopy enthusiast and amateur, including free monthly e-zine, Micscape.) }}</ref>}} A few extremophiles such as ''[[Deinococcus radiodurans]]'' are [[radioresistance|radioresistant]],<ref>{{cite journal | volume=10 | issue=1 | pages=575–577 | last=Anderson | first=A. W. |author2=Nordan, H. C. |author3=Cain, R. F. |author4=Parrish, G. |author5=Duggan, D. | title=Studies on a radio-resistant micrococcus. I. Isolation, morphology, cultural characteristics, and resistance to gamma radiation | journal=Food Technol. | year=1956}}</ref> resisting [[Ionizing radiation|radiation]] exposure of up to 5k [[Gray (unit)|Gy]]. Extremophiles are significant in different ways. They extend terrestrial life into much of the Earth's [[hydrosphere]], [[Crust (geology)|crust]] and [[atmosphere]], their specific evolutionary adaptation mechanisms to their extreme environment can be exploited in [[biotechnology]], and their very existence under such extreme conditions increases the potential for [[extraterrestrial life]].<ref>{{cite journal |author=Cavicchioli, R. |title=Extremophiles and the search for extraterrestrial life |journal=Astrobiology |volume=2 |issue=3 |pages=281–292 |year=2002 |pmid=12530238 |doi=10.1089/153110702762027862 |bibcode=2002AsBio...2..281C |url=http://somosbacteriasyvirus.com/extremophiles.pdf |citeseerx=10.1.1.472.3179 |access-date=26 October 2017 |archive-date=26 April 2022 |archive-url=https://web.archive.org/web/20220426071811/https://somosbacteriasyvirus.com/extremophiles.pdf |url-status=dead }}</ref>

 

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