Astronomers first discovered a chiral organic molecule in interstellar space.
The find can help clarify the origin of life on Earth.
Caltech-based astronomers first discovered a chiral organic matter molecule in interstellar space. This discovery may be important for understanding the origin of life on Earth (and possibly other planets in other star systems). The fact is that amino acids and other organic compounds exist in two forms, called optical isomers. These isomers are identical in composition, but their structure is a mirror opposite. It is possible to distinguish one isomer from another in a solution by passing light through it. Both chiral (mirrored in structure) forms will rotate the plane of polarization of the radiation passing through the solution, left or right. The important point is that all the amino acids that make up the proteins of living organisms (including both viruses and humans) are L-isomers, these are “left-sided” molecules.
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L-isomers have already been found in space, experts have found relatively simple organic compounds on the surface of comets (in particular, on the comet Churyumov-Gerasimenko). The find made now is propylene oxide. On Earth, this substance is well known, it is used in the production of certain types of plastic and as a fumigant in the process of growing almonds. Propylene is also used as a fuel additive. Scientists believe that the detected compound may be in large quantities in the clouds of gas surrounding the center of our galaxy. The chiral molecule discovered by scientists is 390 light years away from Earth. This is a large gas and dust cloud Sagittarius B2. The star formation process is actively going on here. Earlier in the cloud, astronomers discovered several young stars.
The discovery was made using the highly sensitive 100-meter radio telescope Green Bank . The mirror has dimensions of 100 Ă— 110 m. This radio telescope can be sent to any point in the sky with an accuracy exceeding one thousandth of a degree. The minimum working wavelength is 6 mm.
In mirror isomers, it is interesting that the properties of compounds with the same composition, but different in specularity / chirality, may also be different with respect to other chiral objects, such as biological systems. In the pharmaceutical industry, this phenomenon is well known. Ketamine, for example, has a mirror isomer called asketamine. This "twin" of ketamine is a stronger pharmacist than ketamine itself. Metorfan, its R-isomer, is a component of cough syrup. L-isomer is already a powerful opioid used as an anesthetic drug. Naproxen, in one of its incarnations, is an anesthetic drug. In the other - it is poison, literally destroying the liver. All this suggests that the L-isomerism of the amino acids that make up the proteins that form our bodies is not at all accidental. Moreover, only amino acids of the same orientation (either all left-side or all right-side) can form stable proteins.
So far we do not know why life consists of "left-handed" amino acids, but no one argues with this fact. Right-sided isomers of the "amino acids of life" are quite rare on Earth, and do not take part in biochemical reactions.
Complex organic compounds are constantly forming in interstellar space, mainly in dust and gas clouds. It is believed that simpler compounds can collide with each other, forming more and more complex organic substances. With the complication of the compound molecule, new conditions are already needed for the formation of even more complex organic compounds. In some cases, small fragments of water ice, on which individual molecules are deposited, can help. Over time, they become more, and they begin to interact with each other, forming already more complex structures. Complex organics have been found on some comets, including the comet Churyumov-Gerasimenko. Here carbohydrates, alcohols, hydrogen sulfide, hydrocyanic acid, glycine and phosphorus-containing compounds are found. According to experts, these substances can theoretically form even more complex compounds, including amino acids.
According to one theory, life on Earth originated due to the fall of organic comets rich on the surface of our planet in the distant past. Organic matter interacted with each other, gradually forming the "building blocks of life." But the first stage of such a synthesis took place just on comets. Now we can probably say that a similar synthesis takes place in interstellar space.
There is nothing sensational in the very fact of the discovery of a chiral molecule of organic matter in interstellar space. No one doubted that such isomers existed. The discovery of scientists simply confirmed the theory. Unfortunately, the type of chirality of the detected compound has not yet been established. The fact is that there are several types of chirality. These are central (center of chirality), axial (axis of chirality), planar (chirality plane), spiral (spiral), and topological chirality. Experts hope that it will be possible to find out the type of chirality of propylene oxide from interstellar clouds when studying the interaction with the molecules of this compound of polarized light.
Caltech-based astronomers first discovered a chiral organic matter molecule in interstellar space. This discovery may be important for understanding the origin of life on Earth (and possibly other planets in other star systems). The fact is that amino acids and other organic compounds exist in two forms, called optical isomers. These isomers are identical in composition, but their structure is a mirror opposite. It is possible to distinguish one isomer from another in a solution by passing light through it. Both chiral (mirrored in structure) forms will rotate the plane of polarization of the radiation passing through the solution, left or right. The important point is that all the amino acids that make up the proteins of living organisms (including both viruses and humans) are L-isomers, these are “left-sided” molecules.
')
L-isomers have already been found in space, experts have found relatively simple organic compounds on the surface of comets (in particular, on the comet Churyumov-Gerasimenko). The find made now is propylene oxide. On Earth, this substance is well known, it is used in the production of certain types of plastic and as a fumigant in the process of growing almonds. Propylene is also used as a fuel additive. Scientists believe that the detected compound may be in large quantities in the clouds of gas surrounding the center of our galaxy. The chiral molecule discovered by scientists is 390 light years away from Earth. This is a large gas and dust cloud Sagittarius B2. The star formation process is actively going on here. Earlier in the cloud, astronomers discovered several young stars.
The discovery was made using the highly sensitive 100-meter radio telescope Green Bank . The mirror has dimensions of 100 Ă— 110 m. This radio telescope can be sent to any point in the sky with an accuracy exceeding one thousandth of a degree. The minimum working wavelength is 6 mm.
In mirror isomers, it is interesting that the properties of compounds with the same composition, but different in specularity / chirality, may also be different with respect to other chiral objects, such as biological systems. In the pharmaceutical industry, this phenomenon is well known. Ketamine, for example, has a mirror isomer called asketamine. This "twin" of ketamine is a stronger pharmacist than ketamine itself. Metorfan, its R-isomer, is a component of cough syrup. L-isomer is already a powerful opioid used as an anesthetic drug. Naproxen, in one of its incarnations, is an anesthetic drug. In the other - it is poison, literally destroying the liver. All this suggests that the L-isomerism of the amino acids that make up the proteins that form our bodies is not at all accidental. Moreover, only amino acids of the same orientation (either all left-side or all right-side) can form stable proteins.
So far we do not know why life consists of "left-handed" amino acids, but no one argues with this fact. Right-sided isomers of the "amino acids of life" are quite rare on Earth, and do not take part in biochemical reactions.
Complex organic compounds are constantly forming in interstellar space, mainly in dust and gas clouds. It is believed that simpler compounds can collide with each other, forming more and more complex organic substances. With the complication of the compound molecule, new conditions are already needed for the formation of even more complex organic compounds. In some cases, small fragments of water ice, on which individual molecules are deposited, can help. Over time, they become more, and they begin to interact with each other, forming already more complex structures. Complex organics have been found on some comets, including the comet Churyumov-Gerasimenko. Here carbohydrates, alcohols, hydrogen sulfide, hydrocyanic acid, glycine and phosphorus-containing compounds are found. According to experts, these substances can theoretically form even more complex compounds, including amino acids.
According to one theory, life on Earth originated due to the fall of organic comets rich on the surface of our planet in the distant past. Organic matter interacted with each other, gradually forming the "building blocks of life." But the first stage of such a synthesis took place just on comets. Now we can probably say that a similar synthesis takes place in interstellar space.
There is nothing sensational in the very fact of the discovery of a chiral molecule of organic matter in interstellar space. No one doubted that such isomers existed. The discovery of scientists simply confirmed the theory. Unfortunately, the type of chirality of the detected compound has not yet been established. The fact is that there are several types of chirality. These are central (center of chirality), axial (axis of chirality), planar (chirality plane), spiral (spiral), and topological chirality. Experts hope that it will be possible to find out the type of chirality of propylene oxide from interstellar clouds when studying the interaction with the molecules of this compound of polarized light.
Source: https://habr.com/ru/post/395321/
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