Chemical structure of DNA, with a colored label identifying the four bases as well as the phosphate and deoxyribose components of the backbone. Credit: Madprime

New research provides insight into how early life could have begun on Earth.

A team of Czech scientists has managed to produce some of the molecules essential for all life on Earth. These molecules are vital parts of our genetic makeup.

The scientists have tested how the molecules known as nucleotides can be formed naturally. These are made up of nitrogenous bases which provide the structure for DNA and RNA. Often shortened by the letters A, G, and C.

When Extremes Characterized Earth

The Czech team aimed to recreate the conditions on Earth around four billion years ago when the Earth was continually bombarded by space rocks and constant volcanic activity.

The hypothesis is that these extreme conditions with constant electrical reactions and temperature changes allowed for more complex nitrogen molecules to be formed. That the formamide molecules started to break down into the nuclei bases these make up both DNA and RNA.

A LASER Makes Extremes Again

To recreate these conditions the researchers used a powerful laser (The Prague Asterix Laser System) which simulated shock rises in temperature up to 4,500 Kelvin. They also simulated shock waves, multiple radiation sources in the form of ultraviolet (UV), vacuum, extreme UV, and X-ray light.

The team was indeed able to create some very important molecules. As they successfully created five nucleobases from formamide containing plasma. In these conditions, stable but highly reactive CN and NH radicals attack the formamide molecule forming other molecules. And eventually leading to the creation of all the canonical nucleic bases: adenine, guanine, cytosine, thymine, and uracil.

These findings address a central problem in the origin-of-life theory, as it provides insight how life on Earth once appeared. And how it can appear in other places in the universe and what we are to look for when our search for extraterrestrial life continues.

The paper “High-energy Chemistry of formamide: A Unified Mechanism of nucleobase formation” has been published in the scientific journal The Proceedings of the National Academy of Sciences of the United States of America.

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“High-energy Chemistry of formamide: A Unified Mechanism of nucleobase formation”

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