Extremophiles are fascinating organisms capable of surviving in extreme conditions where most life forms could not.
These are primarily microorganisms, which can survive and thrive in extreme environmental conditions that would be lethal or highly inhibitory to most forms of life on Earth.
Types of Extremophiles
Extremophiles are generally classified according to the type of extreme conditions in which they can live:
- Thermophiles and hyperthermophiles: Organisms that thrive at very high temperatures, from 45 °C to over 100 °C, such as in hot springs and hydrothermal vents.
- Psychrophilic: Organisms that live in extremely cold conditions, even below 0 °C, as in the ice of Antarctica.
- Halophiles: Organisms that thrive in environments with high salt concentrations, such as saline lakes or the Dead Sea.
- Acidophilic and alkalophilic: Organisms that live in environments with extremely high or low pH levels, respectively.
- Piezophiles (or barophiles): Organisms that can survive high pressures, as found in the deep ocean.
- Xerophytes: Organisms that can survive in very dry environments, such as deserts.
- Radiophiles: Organisms that resist high levels of ionizing radiation.
Importance of extremophiles
The study of extremophiles has important implications in several fields:
- Biotechnology: Extremophiles are a source of enzymes that can function under extreme industrial conditions, making them useful in processes such as the manufacture of biofuels, bioplastics, and in the pharmaceutical and food industries.
- Astrobiology: Extremophiles expand our understanding of the limits of life and help scientists predict and search for life in extreme extraterrestrial environments, such as Mars or the icy moons of Jupiter and Saturn.
- Ecology and evolution: The study of extremophiles can provide insights into how life may have arisen on Earth and how organisms adapt to extreme conditions.
Applicability of extremophiles in genetics
For DNA analysis, a technique called PCR (polymerase chain reaction) is used to multiply the amount of DNA available for study. Think of PCR as a specialized DNA duplication printer, using an enzyme called Taq polymerase. This enzyme withstands the high temperatures needed to separate DNA strands, focusing on specific segments. Primers", short fragments of DNA, mark the beginning and end of the section to be copied, and under the action of Taq polymerase, multiple copies of this specific section are generated in a few hours.
Taq polymerase comes from Thermus aquaticus, an extremophile capable of withstanding high temperatures found in the hot springs of Yellowstone National Park, USA. Its ability to function between 75-80°C, withstanding up to 95°C, is crucial to the effectiveness of PCR, significantly impacting molecular biology, genetics, forensics and disease diagnosis by simplifying various scientific and medical procedures.
In the field of research, PCR is used to analyze plant or animal genes. A relevant practical case is its use to detect viruses, such as COVID-19, in our organism, improving the diagnosis of diseases. It is also used in DNA tests offered by companies such as ADNTRO to identify genetic predispositions to various characteristics and health conditions.
