A single RNA strand folded on itself with nucleobases (green) and a ribose-phosphate backbone (blue)WIKIMEDIA, VOSSMANRNA consists of a phosphate backbone, sugar, and four bases (A, U, C, G), and has long seemed a promising candidate for early life’s precursor, because of its information-storing capacity and potential to act as a catalyst for certain chemical reactions. But it has been unclear how RNA’s two larger, purine bases (A and G) might have assembled in the conditions present on early Earth. Now, researchers in Germany provide the first demonstration of these bases’ formation from simple media. The team’s findings were published on Wednesday (May 12) in Science.
“We now have a pathway that would allow us to use simple molecules that were likely present on the early Earth,” study coauthor Thomas Carell of Ludwig-Maximilians-Universität München told New Scientist, adding that the next step will be to join those bases into an RNA strand.
Researchers at the University of Manchester in the U.K. demonstrated in 2009 that RNA’s two smaller pyrimidine bases (C and U) could emerge from relatively simple chemicals. In the current study, the Munich-based team revealed a series of chemical reactions leading from similarly simple compounds that readily react in water, such as amines and acids, to large quantities of purine bases. “It’s like a domino cascade,” Carell told Science.
Origins-of-life researcher Gerald Joyce of the Scripps Research Institute in ...
