Meteoric Review Hints At Molecular Diversity

In a find that could open new avenues of inquiry in origin-of-life research, further chemical review of the Murchison meteorite—one of the world’s most studied—suggests it contains millions of organic compounds (Proc. Natl. Acad. Sci. USA, DOI: 10.1073/pnas.0912157107). The Murchison meteorite plummeted to Earth in 1969, and its minimal exposure to earthly contaminants appeals to scientists seeking clues about how molecules delivered by meteorites could have sparked early life. Previous investigations of the meteorite have been targeted to specific compounds, such as amino acids. A team led by Philippe Schmitt-Kopplin of the Helmholtz Center’s Institute of Ecological Chemistry, in Germany, used its metabolomics expertise to conduct a nontargeted molecular search. With ultra-high-resolution mass spectrometry and nuclear magnetic resonance spectroscopy, the team identified signals representing some 14,000 elemental compositions, which they estimate equates to millions of compounds. The discovery shows there’s no shortage of molecules on the meteorite that origin-of-life researchers could investigate, says Jeffrey L. Bada, a cosmogeochemist at Scripps Institution of Oceanography. “The challenge now is to fish out ones that may have some important early biochemical role,” he says.