June 26, 2014
Classic Groundbreaking Experiment On Early Earth Peptides Replicated
Brett Smith for redOrbit.com - Your Universe Online
[ Watch the Video: Stanley Miller’s Forgotten Experiments, Analyzed ]
In a tribute to his old mentor and colleague, a marine chemistry professor at the University of California, San Diego was able to successfully replicate a mysterious and groundbreaking experiment by the “Father of Pre-biotic Chemistry.”
In 1953, chemist Stanley Miller published a report on a landmark experiment that showed how peptides, basic building blocks of life, could have formed in the oceans of the early Earth. The experiment was unusual in that Miller made the head-scratching decision to use the chemical cyanamide, which may or may not have been available on the early Earth.
According to a newly published report in the journal Angewandte Chemie, Miller’s old student and colleague Jeffrey Bada, along with a team of American researchers, were able to replicate the old experiment using modern technology. The team was also able to show that the reaction could have taken place under basic conditions, not solely under acidic conditions as was previously thought.
After Miller suffered a major stroke in 1999, Bada inherited numerous boxes containing samples from his mentor’s old experiments.
"I opened it up and inside were all these other little boxes," Bada said. "I started looking at them, and realized they were from all his original experiments; the ones he did in 1953 that he wrote the famous paper in Science on, plus a whole assortment of others related to that. It's something that should rightfully end up in the Smithsonian."
The famous experiment conducted by Miller, referred to as the electric discharge experiment, involves the replication of the primordial ocean and a tiny electrical charge to spark the development of peptides. The charge represents lighting, which was probably quite prevalent on Earth at the time.
Using modern liquid chromatography and mass spectrometry techniques, the researchers in the new study discovered that the reaction samples from 1958 did indeed contain peptides. The team then set out to replicate the experiment using modern equipment. They were able to verify that the reaction did create peptides.
"What we found were some of the same products of polymerization that we found in the original samples," Parker said. "This corroborated the data that we collected from analyzing the original samples."
The new study also showed that this reaction could take place under basic conditions.
"What we've done is shown that you don't need acid conditions; you just need to have the intermediates involved in amino acid synthesis there, which is very reasonable," Bada said.
One of the biggest mysteries surrounding Miller’s experiments is the use of cyanamide – a chemical used in the production of pharmaceuticals. The study team said they could only speculate as to the reason why Miller chose to include this essential chemical in his experiment.
"Everybody who would have been there and could verify this is gone, so we're just left to scratch our heads and say 'how'd he get this idea before anyone else,'" Bada said.
Like tribute bands putting their own twist on a classic hit, researchers have been regularly delving into Miller’s past work and replicating his greatest experiment in different ways. In 2008, researchers were able to show a much more robust peptide synthesis than the one Miller published in Science in 1953.