LIFE may have begun as a weird molecular hybrid—half-protein, half-RNA,
suggest chemists in California and Texas.
Many biologists believe that RNA was the first self-replicating molecule
because, like DNA, it is composed of chemical bases that spell out the genetic
code, but like protein it’s also capable of a remarkable array of chemical
reactions.
But “the death knell for prebiotic RNA is its sugar,” says Matthew Levy of
the University of Texas, Austin. Under the conditions you might find on early
Earth, the phosphorylated sugar groups which make up RNA’s backbone are unstable
and don’t easily form chains.
But…
