Table of ContentsImportance of ExtremophilesRole of Protein in ExtremophilesExtreme Cold - PsychrophilesExtreme Heat -ThermophilesExtra Salty - HalophilicPolyextremophilesExtremophiles are organisms that live in conditions that humans consider "extreme." “Extreme” environments include, but are not limited to, extreme pressure, extreme cold, extreme heat, highly acidic environments, and highly saline environments. It was once thought that these conditions were unsustainable. Say no to plagiarism. Get a tailor-made essay on “Why Violent Video Games Should Not Be Banned”? Get an original essay There are three domains of life: eukarya, bacteria, and archaea. Each of these domains shares functionality with the other while possessing its own set of characteristics, and none of these domains is ancestral to the others. The most notable extremophiles belong to the archaeal domain. Although penguins are classified as extremophiles, most known extremophiles are microorganisms; The main types of extremophiles studied by scientists belong to the archaeal and bacterial domain of life. Importance of Extremophiles The study of extremophiles can provide us with a solid understanding of the physiochemical limits defining life on our planet. It is assumed that early terrestrial environments were abundant in extreme conditions – most of these environments were extremely hot. This leads to the idea that extremophiles are remnants of ancient organisms and could help understand how life on Earth emerged. Role of Protein in Extremophiles Extremophiles owe most of their ability to survive in such harsh conditions to protein. Protein folding is an essential element for the survival of all living organisms: they are necessary for the growth, function and repair of all living cells. RNA translation is a necessary step in the process of making proteins: without translation, organisms would have no other way to make proteins and therefore function. There is no fundamental set of adaptations suited to every environment. Instead, archaea have evolved distinct protein functions to survive specific environments. By understanding how protein adaptations allow organisms to survive in extreme environments, we hope to be able to understand the limits of life not only on our planet Earth, but also in other places in our solar system. Extreme Cold – PsychrophilesA type of extremophile is called Psychrophiles. . These organisms are able to survive very low temperatures. These organisms are found in perpetually cold areas, for example seabeds, permafrost, glaciers, snowfields and polar regions. The deep waters of the oceans have a fairly stable temperature, at around 2°C. However, the salt content of the water in the colder regions of ocean water allows the water to reach temperatures as low as -12°C without freezing. In fact, microbial activity has been detected in frozen soils below -39°C. Genomics (from the study of genes), proteomics (from the study of proteins) and transcriptomics (from the study of the transcriptome or the expression of genes at specific locations). circumstances), studies suggest that psychrophiles possess various characteristics that allow them to translate RNA and carry out protein folding in cold conditions. InUnder normal conditions, proteins, especially enzymes, lose their activity when temperatures drop below 20°C, which is not a good situation for a psychrophile. cell if it needs to grow. Enzyme activity decreases at low temperatures because the average kinetic energy in the cell is low. Low kinetic energy means that conformational movements become slower and, therefore, less efficient. Psychrophilic proteins are more flexible and are therefore better able to move and change conformation. This means that psychrophilic proteins can maintain high activity even at low temperatures. Additionally, a psychrophilic enzyme generally has 10 times more activity than a mesophilic enzyme (at normal temperature). Extreme Heat-ThermophilesThermophiles are capable of growing between 50°C and 70°C, while hyperthermophiles can grow optimally up to 105°C, with a limit of 110°C to 121°C. These organisms can be found in geothermally heated terrestrial and marine habitats, including volcanic island sediments, hydrothermal vent systems, shallow terrestrial hot springs, and deep-sea hydrothermal vents. All cells have an outer membrane which regulates what enters and leaves the cell. The cell membrane also serves to protect the internal contents of the cell from the environment. A universal component of the cell membrane is the lipid bilayer, which constitutes the barrier in the membrane. Lipids being fats, they are insoluble in water. The most common class of lipid molecules found in the bilayer is phospholipids. In extremely hot conditions, the cell membranes of “normal” organisms will be more flexible – when the membrane is more flexible, this can lead to cell lysis – which causes the membrane to break down, and the cell will not be able to protect itself and she will die. Another fate that awaits “normal” proteins in extreme heat is that they can undergo irreversible unfolding, exposing hydroponic cores, which causes aggregation. When proteins form aggregates, they no longer function properly. In thermophiles, however, phospholipids exhibit certain adaptations. The fatty acids in phospholipids are longer, have more side chains and are saturated. The increased number of large hydrophobic residues, disulfide bonds, and ionic interactions promote thermostability. Better support of thermophiles would prevent water molecules from penetrating inside and destabilizing the protein core (water destabilizes proteins due to its effectiveness in hydrogen bonding with the macromolecule). This provides a rigid membrane, giving it a stable membrane in a hot environment. To prevent denaturation and aggregate formation, the thermophile can form heat shock proteins. When these proteins form, they can prevent the protein from forming aggregates, they can also fold the protein structure, which can allow the protein to function in the cell. Extra Salty – Halophile Halophiles are salt-loving organisms that thrive in saline environments. These organisms can be found in hypersaline environments all over the world, in underground salt mines, coastal areas and the open ocean, as well as in artificial salt flats. The Dead Sea and the Great Salt Lake, which are extremely salty environments, are notable examples of places where halophilic organisms can be found. Sodium chloride is capable of modifying the conformation, stability and solubility of a.