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Extremeophiles and Extreme Environments: January 2011


Geomicrobiologist Felisa Wolfe-Simon, collecting lake-bottom sediments in the shallow waters of Mono Lake in California. Wolfe-Simon cultured the arsenic-utilizing organisms from this hypersaline and highly alkaline environment. Credit: (c)2010 Henry Bortman

One of the basic assumptions about life on Earth may be due for a revision thanks to research supported by NASA's Astrobiology Program. Geomicrobiologist Felisa Wolfe-Simon has discovered a bacterium in California's Mono Lake that uses arsenic instead of phosphorus in its DNA. Up until now, it was believed that all life required phosphorus as a fundamental piece of the 'backbone' that holds DNA together. The discovery of an organism that thrives on otherwise poisonous arsenic broadens our thinking about the possibility of life on other planets, and begs a rewrite of biology textbooks by changing our understanding of how life is formed from its most basic elemental building blocks.

Wolfe-Simon's research is supported by NASA's Exobiology and Evolutionary Biology (Exo/Evo) Program and the NASA Astrobiology Institute. Among the goals of these programs is determining the evolution of genes, metabolic pathways, and microbial species on Earth in order to understand the potential for life on other worlds. Wolfe-Simon's discovery represents the first time in the history of biology that an organism has been found to use a different element to build one of its most basic structures. The paper appeared in the December 2nd, 2010 issue of "Science Express" and subsequently published in the journal Science. [Source: NAI Newsletter]

Researchers from the NASA Astrobiology Program have discovered amino acids in a meteorite where none were expected. "This meteorite formed when two asteroids collided," said Dr. Daniel Glavin of NASA's Goddard Space Flight Center, Greenbelt, Md. "The shock of the collision heated it to more than 2,000 degrees Fahrenheit, hot enough that all complex organic molecules like amino acids should have been destroyed, but we found them anyway." Glavin is lead author of a paper on this discovery appearing December 13 in Meteoritics and Planetary Science. "Finding them in this type of meteorite suggests that there is more than one way to make amino acids in space, which increases the chance for finding life elsewhere in the Universe."

A new online guidebook helps people understand how astrobiology research ties to Yellowstone National Park. The guidebook, entitled "Secrets of the Springs: Astrobiology in Yellowstone National Park," features an outline of astrobiology and its three fundamental questions; a map of astrobiology-related sites in Yellowstone; and an overview of "extreme environments" and their connection to the search for extra-terrestrial life.

The book was created by astrobiology researchers at Montana State University with support from the NASA Astrobiology Institute.

The book can be downloaded in PDF format at http://abrc.montana.edu/outreach/scienceofthesprings.html or viewed online at http://bit.ly/h82DDO

Printed copies of the guidebook are free for teachers to use as a classroom resource. Museums and science centers may also have free print copies. Contact Suzi Taylor with MSU Extended University at taylor@montana.edu

Montana State University's Extended University offers workforce training and professional development, science education and public outreach, educational technologies and distance learning courses, degrees and certificates via Montana State Online.