Origin & Evolution of Life: November 2008

Miller-Urey Revisited

Members of NAI's Carnegie Institution of Washington, Indiana University, and NASA Goddard Space Flight Center Teams and their colleagues have revisited the Miller-Urey experiments, and found some surprising results.

A classic experiment proving amino acids are created when inorganic molecules are exposed to electricity isn't the whole story, it turns out. The 1953 Miller-Urey Synthesis had two sibling studies, neither of which was published. Vials containing the products from those experiments were recently recovered and reanalyzed using modern technology. The results are reported in Science.

Starting January 1, 2009, a new 4-year program will investigate hydrothermal systems on the Mid-Cayman Spreading Center (MCSC) under NASA's ASTEP program - a joint collaboration between Woods Hole Oceanographic Institution (WHOI), NASA's Jet Propulsion Laboratory (JPL), the Marine Biological Laboratory (MBL) and Duke University Marine Laboratory (DUML). The results of the work will be used to plan astrobiological exploration of any planetary body that can host hydrothermal circulation (for example, Europa).

Mirror-Image Clues to Life's Origins

According to an article published in the Washington Post, scientists studying the Murchison meteorite have found that it contains clues to the origin of chirality. Amino acids in nature have two forms, referred to as right- and left-handed, that are mirror images of each other. The proteins in living organisms, however, are only made from left-handed amino acids. The reason for this chirality is not understood, but this new research suggests it may stem from meteorites that rained down on the young Earth.

Source; NAI Newsletter

Life Without the Sun

An ecosystem discovered 2.8 kilometers underground in the Mponeng Gold Mine near Johannesburg, South Africa two years ago has now been shown to comprise only a single species of microbe, existing on energy from radioactivity, completely independently of the Sun. The community of rod-shaped bacteria of the species Desulforudis audaxviator was discovered in 2005-06 by members of the NAI's Indiana-Princeton-Tennessee Astrobiology Initiative (IPTAI) Team. Their current results are presented in the October 10th issue of Science.