title: Amino acid racemization on Mars:  implications for the preservation of biomolecules from an extinct martian biota.
abstract: Using kinetic data, we have estimated the racemization half-lives and times for total racemization of amino acids under conditions relevant to the surface of Mars. Amino acids from an extinct martian biota maintained in a dry, cold (<250 K) environment would not have racemized significantly over the lifetime of the planet. Racemization would have taken place in environments where liquid water was present even for time periods of only a few million years following biotic extinction. The best preservation of both amino acid homochirality and nucleic acid genetic information associated with extinct martian life would be in the polar regions.
authors.affiliation: Scripps Institution of Oceanography, University of California, San Diego, La Jolla 92093-0212, USA. jbada@ucsd.edu
authors.forename: J L
authors.initials: JL
authors.lastname: Bada
authors.forename: G D
authors.initials: GD
authors.lastname: McDonald
mesh_terms: D000596:Amino Acids / Q000737:chemistry; D001224:Aspartic Acid / Q000737:chemistry*; D003080:Cold Temperature; D019418:Evolution, Chemical; D006358:Hot Temperature; D007532:Isoleucine / Q000737:chemistry*; D007536:Isomerism; D018535:Mars; D000069497:Origin of Life
chemical_list: D000596:Amino Acids; D007532:Isoleucine; D001224:Aspartic Acid