Extremophile
Channel: 宇宙のすべての知識 プリンシピア
Date: 04/02/2019

Extremophile, by Wikipedia https://en.wikipedia.org/wiki?curid=9619 / CC BY SA 3.0

#Extremophiles
#Environmental_microbiology
#Astrobiology
#Bacteria
#Ecology
#Geomicrobiology
#Microbial_growth_and_nutrition
Extremophile

An extremophile (from Latin ' meaning "extreme" and Greek ' () meaning "love") is an organism that thrives in physically or geochemically extreme conditions that are detrimental to most life on Earth. In contrast, organisms that live in more moderate environments may be termed mesophiles or neutrophiles.

In the 1980s and 1990s, biologists found that microbial life has great flexibility for surviving in extreme environments—niches that are acidic or extraordinarily hot, for example—that would be completely inhospitable to complex organisms. Some scientists even concluded that life may have begun on Earth in hydrothermal vents far under the ocean's surface.

According to astrophysicist Steinn Sigurdsson, "There are viable bacterial spores that have been found that are 40 million years old on Earth—and we know they're very hardened to radiation." Some bacteria were found living in the cold and dark in a lake buried a half-mile deep under the ice in Antarctica, and in the Marianas Trench, the deepest place in Earth's oceans. Some microorganisms have been found thriving inside rocks up to below the sea floor under of ocean off the coast of the northwestern United States. According to one of the researchers, "You can find microbes everywhere—they're extremely adaptable to conditions, and survive wherever they are." A key to extremophile adaptation is their amino acid composition, affecting their protein folding ability under particular conditions.

There are many classes of extremophiles that range all around the globe; each corresponding to the way its environmental niche differs from mesophilic conditions. These classifications are not exclusive. Many extremophiles fall under multiple categories and are classified as polyextremophiles. For example, o...