Amino acids created in deep-space-like environment
NASA NEWS RELEASE
Posted: March 28, 2002

NASA scientists announced Wednesday the creation of amino acids, critical for life, in an environment that mimics deep space. The research will be published in the March 28 issue of the journal Nature.

In a laboratory at NASA Ames Research Center in California's Silicon Valley, the team of astrobiologists shone ultraviolet light on deep-space-like "ices," simulating conditions that are commonplace in interstellar space. Deep-space ice is common water ice laced with simple molecules. The team subsequently discovered amino acids, molecules present in, and essential for, life on Earth.

"This finding may shed light on the origin of life itself," said Dr. Max Bernstein, the first author and chemist at NASA Ames and the SETI Institute. "We found that amino acids can be made in the dense interstellar clouds where planetary systems and stars are made. Our experiments suggest that amino acids should be everywhere, wherever there are stars and planets."

Art
Illustration shows the connection between interstellar ices via comets and asteroids to life on Earth. See terms of use note. Credit: NASA-Ames
 
The amino acids they detected (glycine, alanine and serine) are the basic parts of proteins from which all life is made. Proteins provide the structure for, and do all the work in, living things.

The amino acids produced in the NASA Ames lab are similar to those found previously in carbon-rich meteorites. Meteorites are pieces of asteroids or comets that have fallen to Earth. The chemical similarities may indicate that amino acids in meteorites were made in deep space, before the solar system formed, the scientists say.

"This finding suggests that Earth may have been seeded with amino acids from space in its earliest days," said Jason Dworkin of Ames and the SETI Institute. "And, since new stars and planets are formed within the same clouds in which new amino acids are being created, this increases the odds that life also evolved in places other than Earth."

"Taken in combination, these results suggest that interstellar chemistry may have played a significant part in supplying the Earth with some of the organic materials needed to jump-start life," Dworkin concluded.

To conduct their experiments, the research team simulated space-like conditions by freezing mixtures of molecules (such as wood alcohol and ammonia) that are abundant in interstellar clouds. They then exposed the resulting ice to ultraviolet light.

Previously, the team demonstrated that irradiating interstellar ice 'look-alikes' generated compounds called amphiphiles that can organize themselves to form membranes; and molecules called quinones that play important roles in the metabolism of all living organisms on Earth. The next step, they say, will be to tackle the issue of left- and right-handed amino acids. Both forms exist in space, but only the left-handed forms are used by life on Earth.

In addition to the principals, other scientists on the team included Drs. Louis Allamandola, George Cooper and Scott Sandford, all of Ames.

Astrobiology is the multidisciplinary study of the origin, evolution, distribution and future of life in the universe. NASA Ames Research Center is the location of the central offices of the NASA Astrobiology Institute and serves as the agency's lead center for astrobiology.