Stinky Origins to Life? New Analysis Yields Clues

A new NASA-funded study demonstrates how a chemical that smells like rotten eggs -- hydrogen sulfide -- may have played a role in the formation of life on Earth. The study authors, including Andrew Aubrey of NASA's Jet Propulsion Laboratory, re-examined old test tubes from classic experiments performed in the 1950s by Stanley Miller, who was a graduate student at the University of Chicago.

The team analyzed samples from another variant of the experiment performed in 1958 in which Miller used carbon dioxide and hydrogen sulfide gas in the mixture. It was "lost" for decades because, for unknown reasons, Miller never reported his analysis of the results. "Stanley mentioned to several of us that he hated working with hydrogen sulfide because it smelled so bad and tended to make him sick," said Jeffrey Bada of the Scripps Institution of Oceanography, University of California at San Diego, who was a graduate student of Miller's and is the corresponding author on the new study.

"Given that some of the compounds he made in the experiment smell pretty bad, this experiment may be the basis for his reluctance to deal with hydrogen sulfide in experiments," he said.

The team discovered that the experiment created amino acids containing sulfur, the first such synthesis from a simulated prebiotic environment, according to team members, and the one that produced them in the greatest diversity and highest abundance.

The results provide clues about the roles that volcanic plumes -- which are a natural source of hydrogen sulfide -- may have played in producing the Earth's first organic compounds.

For more information visit http://www.jpl.nasa.gov/news/news.cfm?release=2011-093