Science Daily – Mar. 6, 2013 — University of Georgia researchers discovered important genetic clues about the history of microorganisms called archaea and the origins of life itself in the first ever study of its kind. Results of their study shed light on one of Earth’s oldest life forms.

Science Daily reports:
Feb. 20, 2013 — The base pairs that hold together two pieces of RNA, the older cousin of DNA, are some of the most important molecular interactions in living cells. Many scientists believe that these base pairs were part of life from the very beginning and that RNA was one of the first polymers of life. But there is a problem. The RNA bases don’t form base pairs in water unless they are connected to a polymer backbone, a trait that has baffled origin-of-life scientists for decades. If the bases don’t pair before they are part of polymers, how would the bases have been selected out from the many molecules in the “prebiotic soup” so that RNA polymers could be formed?

Dec. 20, 2012 — A coherent pathway — which starts from no more than rocks, water and carbon dioxide and leads to the emergence of the strange bio-energetic properties of living cells — has been traced for the first time in a major hypothesis paper in Cellthis week.

At the origin of life the first protocells must have needed a vast amount of energy to drive their metabolism and replication, as enzymes that catalyse very specific reactions were yet to evolve. Most energy flux must have simply dissipated without use.

The question of how life began on a molecular level has been a longstanding problem in science. However, recent mathematical research sheds light on a possible mechanism by which life may have gotten a foothold in the chemical soup that existed on the early Earth.
Researchers have proposed several competing theories for how life on Earth could have gotten its start, even before the first genes or living cells came to be. Despite differences between various proposed scenarios, one theme they all have in common is a network of molecules that have the ability to work together to jumpstart and speed up their own replication — two necessary ingredients for life. However, many researchers find it hard to imagine how such a molecular network could have formed spontaneously — with no precursors — from the chemical environment of early Earth.

Scientists believe that prior to the advent of DNA as Earth’s primary genetic material, early forms of life used RNA to encode genetic instructions. What sort of genetic molecules did life rely on before RNA?