Theoretical origin of life; more on hydrothermal vents (Introduction)

by David Turell , Tuesday, February 26, 2019, 20:06 (2097 days ago) @ David Turell

A lab mimics the vents and gets some proteins:

https://phys.org/news/2019-02-nasa-life-ocean-floor.html

"Scientists have reproduced in the lab how the ingredients for life could have formed deep in the ocean 4 billion years ago. The results of the new study offer clues to how life started on Earth and where else in the cosmos we might find it.

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" Found around cracks in the seafloor, hydrothermal vents are places where natural chimneys form, releasing fluid heated below Earth's crust. When these chimneys interact with the seawater around them, they create an environment that is in constant flux, which is necessary for life to evolve and change. This dark, warm environment fed by chemical energy from Earth may be the key to how life could form on worlds farther out in our solar system, far from the heat of the Sun.

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"Barge and Flores used ingredients commonly found in early Earth's ocean in their experiments. They combined water, minerals and the "precursor" molecules pyruvate and ammonia, which are needed to start the formation of amino acids. They tested their hypothesis by heating the solution to 158 degrees Fahrenheit (70 degrees Celsius)—the same temperature found near a hydrothermal vent—and adjusting the pH to mimic the alkaline environment. They also removed the oxygen from the mixture because, unlike today, early Earth had very little oxygen in its ocean. The team additionally used the mineral iron hydroxide, or "green rust," which was abundant on early Earth.

"The green rust reacted with small amounts of oxygen that the team injected into the solution, producing the amino acid alanine and the alpha hydroxy acid lactate. Alpha hydroxy acids are byproducts of amino acid reactions, but some scientists theorize they too could combine to form more complex organic molecules that could lead to life.

"'We've shown that in geological conditions similar to early Earth, and maybe to other planets, we can form amino acids and alpha hydroxy acids from a simple reaction under mild conditions that would have existed on the seafloor," said Barge.

"Barge's creation of amino acids and alpha hydroxy acids in the lab is the culmination of nine years of research into the origins of life. Past studies looked at whether the right ingredients for life are found in hydrothermal vents, and how much energy those vents can generate (enough to power a light bulb). But this new study is the first time her team has watched an environment very similar to a hydrothermal vent drive an organic reaction. Barge and her team will continue to study these reactions in anticipation of finding more ingredients for life and creating more complex molecules. Step by step, she's slowly inching her way up the chain of life."

Comment: It takes very much more than two amino acids to get to RNA. As usual lots of hope in this research.