While many people may find 50°C (roughly 120°F) to be quite past their comfort zone, many thermophiles thrive between 45 and 122°C, with the toleration for the higher end (< 75°C) being hyperthermophiles. Thermophiles are organisms that can withstand – and sometimes even require – high temperatures to survive, hence their meaning “heat-loving.”
Thermophiles are both prokaryotic and eukaryotic, though the microorganisms growing in the most extreme environments are archaea. Hot springs and deep-sea thermal vents can be found throughout the world, but a number of the studied thermophiles are concentrated in Yellowstone National Park, USA.
What makes thermophiles so interesting is their ability to survive under high temperatures without denaturing their proteins. Thermophiles have special enzymes called extremozymes that are more tightly bound than enzymes at normal temperatures. Additionally, thermophile enzymes tend to have less glycine. Since glycine is the smallest and simplest amino acid, it typically allows proteins to be more flexible. Having less glycine in their structures would allow extremozymes to be more rigid and more resistant against extreme temperatures.
Since extremozymes are able to function under extreme conditions, these enzymes have become well incorporated in biotechnological applications, such as PCR.
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