The prebiotic synthesis of pyrimidines in frozen solution.
Most prebiotic syntheses depend on the reaction of concentrated precursor compounds to produce bio-organic molecules. It is now believed that the early Earth's atmosphere was not reducing enough to have permitted copious synthesis of precursor molecules. Freezing allows reaction to occur even from dilute solution. This reaction has been demonstrated for the purines but not for the pyrimidines. It is shown here that dilute solutions of simple prebiotic molecules produce the biological pyrimidines cytosine and uracil upon freezing. Cold environments may have allowed synthesis of all of the RNA bases even from low organic yielding atmospheres, such as those of the early Earth, Mars, Titan and Europa.
Geosciences Research Division, The Scripps Institution of Oceanography, 9500 Gilman Drive, La Jolla, CA 92093-0212, USA. hcleaves@ucsd.edu
H James
HJ
Cleaves
Kevin E
KE
Nelson
Stanley L
SL
Miller
D018534:Earth, Planet; D019418:Evolution, Chemical; D005615:Freezing; D018538:Jupiter; D018535:Mars; D000069497:Origin of Life; D011743:Pyrimidines / Q000138:chemical synthesis*; D012313:RNA / Q000138:chemical synthesis; D018539:Saturn; D012996:Solutions
D011743:Pyrimidines; D012996:Solutions; D012313:RNA