The meteorite that fell to Earth has all the components of DNA, RNA

Discovered 2 more components of DNA, RNA

The researchers said on April 26 that they had identified the last two of the five that are needed to form DNA, the molecule that carries genetic instructions in living organisms, and RNA, the key molecule. important for controlling gene activity after fine-tuning the analysis of meteorite. Previously, scientists had identified these meteorites as having three of the five chemical components needed to form DNA and RNA.

Unlike previous meteorite studies, the method used this time is more sensitive and does not use strong acids or hot liquids to extract five components, called nucleobases, according to astrochemist Yasuhiro Oba of Hokkaido University’s Institute of Low Temperature Science in Japan, lead author of the study published in the journal Nature Communications.

Nucleobases are nitrogenous compounds that are important in the formation of the characteristic double helix structure of DNA.

Study co-author Danny Glavin, an astrobiologist at NASA’s Goddard Space Flight Center in Maryland, confirmed the extraterrestrial origin of a complete set of nucleobases found in DNA and RNA. supports the hypothesis that meteorites may have been an important source of organic compounds necessary for the emergence of the first living organisms on Earth.

Scientists are trying to better understand the events that took place on Earth The earth leads to different chemical compounds combining in warm water to form a living organism that can reproduce on its own. The formation of DNA and RNA will be an important milestone because these molecules essentially contain the instructions for building and operating living organisms.

“There is still much to learn about the chemical steps that led to the origin of life on Earth – the first self-regenerating system. This study certainly adds to the list of chemical compounds found in the “primordial soup” (which existed before life appeared) of the early Earth,” Glavin said.

3 meteorites fell to Earth in the US, Canada, Australia

The researchers examined three meteorites – one that fell in 1950 near the town of Murray in the US state of Kentucky, a meteorite that fell in 1969 near the town of Murchison in the Australian state of Victoria, and one Meteor falls in 2000 near Lake Tagish in British Columbia, Canada.

All three meteorites in the study are classified as carbonaceous chondrites, which are made of rocky material believed to have formed early in the history of the Solar System. This group of meteorites is rich in carbon, with the Murchison and Murray meteorites containing about 2% organic carbon by weight and the Lake Tagish meteorites containing about 4% organic carbon. Carbon is the main component of organisms on Earth.

“All three meteorites contain a very complex mixture of organic molecules, most of which have yet to be identified,” Glavin said.

Earth formed about 4.5 billion years ago. During its infancy, Earth was heavily bombarded by meteors, comets, and other matter from space. The first creatures of this planet were primitive microorganisms in the primordial seas. The earliest known fossils on Earth are samples of marine microorganisms dating to about 3.5 billion years ago, although there are signs of life in the fossils. fossil older.

The researchers inform the researchers that the two nucleobases, called cytosine and thymine, newly identified in meteorites may not have been detected in previous tests because they are structurally more sophisticated than the three emitters. present before.

In addition to the 5 nucleobases necessary for life, other essential chemical compounds are amino acids – components of proteins and enzymes; sugar – is a component of the DNA and RNA backbones; and fatty acids – structural components of cell membranes.

“Current results may not directly shed light Origin of life on Earth but I believe they can increase our understanding of the inventory of organic molecules on the early Earth before life began,” said astrophysicist Yasuhiro Oba.