Editing Extremophile (section)

===Definitions===
[[File:Microorganisms from the hypersaline Lake Tyrrell.jpg|thumb|upright=1.5| Microscopic image from the hypersaline [[Lake Tyrrell]] (salinity> 20% w/v), in which the eukaryotic [[chlorophyte]], ''[[Dunaliella salina]]'', can be tentatively identified. ''Dunaliella salina'' is grown commercially for the carotenoid, [[β-carotene]], which is widely used as a natural food colorant as well as a precursor to vitamin A. Alongside is the haloarchaeon, ''[[Haloquadratum walsbyi]]'', which has flat square-shaped cells with gas vesicles that allow flotation to the surface, most likely to acquire oxygen.]]

*[[Acidophile (organisms)|Acidophile]]: an organism with optimal growth at [[pH]] levels of 3.0 or below.

*[[Alkaliphile]]: an organism with optimal growth at [[pH]] levels of 9.0 or above.

*[[Capnophile]]: an organism with optimal growth conditions in high concentrations of carbon dioxide. An example would be ''[[Mannheimia succiniciproducens]],'' a bacterium that inhabits a ruminant animal's digestive system.<ref>{{Cite journal |last1=Hong |first1=Soon Ho |last2=Kim |first2=Jin Sik |last3=Lee |first3=Sang Yup |last4=In |first4=Yong Ho |last5=Choi |first5=Sun Shim |last6=Rih |first6=Jeong-Keun |last7=Kim |first7=Chang Hoon |last8=Jeong |first8=Haeyoung |last9=Hur |first9=Cheol Goo |last10=Kim |first10=Jae Jong |date=2004-09-19 |title=The genome sequence of the capnophilic rumen bacterium Mannheimia succiniciproducens |journal=Nature Biotechnology |volume=22 |issue=10 |pages=1275–81 |doi=10.1038/nbt1010 |issn=1087-0156 |pmid=15378067 |doi-access=free |s2cid=35247112}}</ref>

*[[Halophile]]: an organism with optimal growth at a concentration of dissolved salts of 50&nbsp;g/L (= 5% m/v) or above (for comparison, the [[ocean salinity]] is about 35&nbsp;g/L (= 3.5% m/v)).

*[[Piezophile|Hyperpiezophile]]: an organism with optimal growth at [[hydrostatic pressure]]s above 50&nbsp;MPa (= 493&nbsp;atm = 7,252&nbsp;psi).

*[[Hyperthermophile]]: an organism with optimal growth at temperatures above {{Convert|80|C||abbr=on}}.

*[[Metallotolerant]]: an organism capable of tolerating high levels of dissolved heavy metals in solution, such as [[copper]], [[cadmium]], [[arsenic]], and [[zinc]]. Examples include ''[[Ferroplasma]] sp.'', ''[[Cupriavidus metallidurans]]'' and [[GFAJ-1]].<ref name="refute">{{Cite news |date=9 July 2012 |title=Studies refute arsenic bug claim |work=BBC News |url=https://www.bbc.co.uk/news/science-environment-18770964 |access-date=10 July 2012}}</ref><ref>{{Cite journal |author-link5=Julia Vorholt |vauthors=Erb TJ, Kiefer P, Hattendorf B, Günther D, Vorholt JA |date=July 2012 |title=GFAJ-1 is an arsenate-resistant, phosphate-dependent organism |journal=Science |volume=337 |issue=6093 |pages=467–70 |bibcode=2012Sci...337..467E |doi=10.1126/science.1218455 |pmid=22773139 |s2cid=20229329|doi-access=free }}</ref><ref>{{Cite journal |vauthors=Reaves ML, Sinha S, Rabinowitz JD, Kruglyak L, Redfield RJ |date=July 2012 |title=Absence of detectable arsenate in DNA from arsenate-grown GFAJ-1 cells |journal=Science |volume=337 |issue=6093 |pages=470–73 |arxiv=1201.6643 |bibcode=2012Sci...337..470R |doi=10.1126/science.1219861 |pmc=3845625 |pmid=22773140}}</ref>

*[[Oligotroph]]: an organism with optimal growth in nutritionally limited environments.

*[[Osmophile]]: an organism with optimal growth in environments with a high sugar concentration.

*[[Piezophile]] or barophile: an organism with optimal growth in [[hydrostatic pressure]]s above 10&nbsp;MPa (= 99&nbsp;atm = 1,450&nbsp;psi).

*Polyextremophile (mixed Latin/Greek compound for ''affection for many extremes''): not a well-defined category itself – an organism that qualifies as an extremophile under more than one category.

*[[Psychrophile]] or cryophile: an organism with optimal growth at temperatures of {{Convert|15|C||abbr=}} or lower.

*[[Radioresistant]]: organisms resistant to high levels of [[ionizing radiation]], most commonly [[ultraviolet radiation]]. This category also includes organisms capable of resisting [[nuclear radiation]], notably [[gamma ray]]s.

*Sulphophile: an organism with optimal growth conditions in high concentrations of [[sulfur]]. An example would be ''[[Sulfurovum epsilonproteobacteria]]'', a sulfur-oxidizing bacteria that inhabits deep-water sulfur vents.<ref>{{Cite journal |last1=Meier |first1=Dimitri V |last2=Pjevac |first2=Petra |last3=Bach |first3=Wolfgang |last4=Hourdez |first4=Stephane |author5-link=Peter Girguis|last5=Girguis |first5=Peter R |last6=Vidoudez |first6=Charles |last7=Amann |first7=Rudolf |last8=Meyerdierks |first8=Anke |date=2017-04-04 |title=Niche partitioning of diverse sulfur-oxidizing bacteria at hydrothermal vents |journal=The ISME Journal |volume=11 |issue=7 |pages=1545–58 |doi=10.1038/ismej.2017.37 |issn=1751-7362 |pmc=5520155 |pmid=28375213|bibcode=2017ISMEJ..11.1545M }}</ref>

*[[Thermophile]]: an organism with optimal growth at temperatures above {{Convert|45|C||abbr=on}}.

*[[Xerophile]]: an organism with optimal growth at [[water activity]] below 0.8.