Astrobiology Science and Technology for Exploring Planets (ASTEP)

Seminar Detail

Pyrite-generated radicals and the destruction of nucleic acids

Presenter: Corey Cohn

May 10, 2004 01:00 PM Pacific

Generation of radical species (e.g., *OH) by silica is well documented and
it has also been shown these radicals can readily destroy biomolecules.
While silica has received considerable attention, pyrite (FeS2), the most
abundant iron sulfide, has received almost no attention in this context.
The origin and reactivity as well as effects of mineral pretreatment,
solution chemistry, and mineral bulk/surface chemistry on the formation of
oOH in pyrite-water systems are not well understood and are the goals of
this research. In this study, the reactivity of pyrite is studied by the
decomposition of RNA and DNA, representative biomolecules, which is also a
commonly used method for the detection of *OH. Batch experiments using a
number of different detection techniques show that pyrite induces ruptures
in the macromolecules. The formation of *OH by pyrite could have
fundamental implications for the stability of organics during the origin
and evolution of life.

Participation Instructions

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