NEW STUDY ANALYZES UNKNOWN SAMPLES FROM FAMOUS CHEMIST, STANLEY MILLER
Chemist Stanley Miller, whose landmark experiment published in 1953 showed how some of the molecules of life could have formed on a young Earth, left behind boxes of samples, some of which he never analyzed, from his 1950s experiments. The first-ever analysis of some of these old samples has revealed another way that important molecules could have formed on early Earth.
The study discovered a path from simple to complex compounds amid Earth’s prebiotic soup. More than 4 billion years ago, amino acids could have been attached together, forming peptides. These peptides ultimately may have led to the proteins and enzymes necessary for life’s biochemistry.
In the new study, scientists analyzed samples from an experiment Miller performed in 1958. To the reaction flask, Miller added the chemical cyanimide, which at the time wasn’t widely thought to have been available on early Earth. The new study found that the 56-year-old reaction had successfully formed peptides.
“It was clear that the results from this old experiment weren’t some sort of artifact. They were real,” said Jeffrey Bada, distinguished professor of marine chemistry at the Scripps Institution of Oceanography at UC San Diego. Bada was a former student and colleague of Miller’s.
The study was supported by the Center for Chemical Evolution at Georgia Tech, which is jointly supported by the National Science Foundation and the NASA Astrobiology Program. The study was published in the journal Angewandte Chemie International Edition and resulted from collaboration spearheaded by UC San Diego and Georgia Tech. Scientists from NASA’s Johnson Space Center and Goddard Space Flight Center were also involved in the analysis. Eric Parker, the study’s lead author, was an undergraduate student in Bada’s laboratory and is now a graduate student at Georgia Tech.
The 1958 reaction samples were analyzed by Parker and his current mentor, Facundo M. Fernández, a professor in the Georgia Tech School of Chemistry and Biochemistry. Liquid chromatography and mass spectrometry showed that the reaction samples from 1958 contained peptides.
In addition to analyzing the 1958 samples, Parker designed a way to conduct the experiment using modern equipment and confirmed that the reaction created peptides.
“We found some of the same products of polymerization that we found in the original samples,” Parker said. “This corroborated the data we collected from analyzing the original samples.”