The molecule that corresponds to the "D" in DNA could exist in space


New research suggests that the sugar molecule that places the "D" in DNA, 2-deoxyribose, could exist in the confines of space. A team of NASA astrophysicists was able to create DNA from sugar under laboratory conditions that mimic interstellar space. The results represent the first solid evidence of sugar formation in DNA in an astrophysical environment.

The researchers believe that their results, published in Communications of the natureshow that another of the critical chemical components of life could be diffused in the universe and potentially plant other planets as well.

"We still do not know if life is common in the universe, but we are sure that the presence of the basic components of life is not a limiting factor "he said Michel New, a researcher at NASA's Ames Research Center, the lead author of the paper.

The vast, frigid low-density regions between the stars are not as empty as they seem. The interstellar medium contains dust and gases, and these are bombarded by photons and high-energy particles. Chemical reactions occur, although they are extremely slow at temperatures around -226 degrees Celsius.

These were the conditions that Nuevo and his team simulated in the "cosmic camera" at Ames Astrophysics and Astrochemistry Laboratory. The team used a vacuum chamber that contained an almost zero absolute cooled aluminum substance and added a gaseous mixture of common water vapor and methanol composed of carbon.

At such a low temperature, an icy layer formed on the surface of the substance. After irradiating the chamber with ultraviolet light and heating the substance, the researchers examined the resulting material and found that a variety of sugar derivatives were created, as well as the 2-deoxyribose sugar complex.

In 2016, another team of researchers in France similar discovery in the laboratory of ribose, the sugar RNA used by the body to produce proteins and considered a possible precursor of DNA in the early life forms on primitive Earth.

"For more than two decades we wondered if the chemistry we found in space could make the kinds of compounds essential to life, so far we have not chosen a large set of molecules that can not be produced," he said. Scott Sandford, lead scientist at the Ames Astrochemistry Laboratory and author of the new article.

These complex sugars add increasing list of organic compounds found in meteorites and under laboratory conditions of the cosmic type. These include amino acids, the building blocks of proteins; nucleobases, the basic units of the genetic code; and amphiphiles, the class of molecules used by life to produce membranes around the cells.

"The universe is an organic chemical," Sandford said in a statement. "It has large vessels and a lot of time, and the result is a lot of organic material, some of which they are useful for life"

As the rotating remnants of the interstellar medium condense into new stars and planetary systems, how do the organic molecules created in space reach the surface of newly formed planets?

Early Earth was probably bathed by materials such as meteoroids and comets that hit its surface. Sugar derivatives such as sugar acids and sugar alcohols were found in these samples. These sugar derivatives can evolve into the sugars used in DNA and RNA in the presence of water, which gives researchers new ways to explore the chemistry of early life.


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