The Primordial Lab for the Origin of Life
Exploring the role of RNA, DNA, nucleic acids, proteins and other elements that inform our understanding of the origins of life.
Published April 1, 2002
By Henry Moss, PhD
Academy Contributor

When Thomas Cech and Sidney Altman showed that the ribozyme, a form of RNA, could act in the same manner as a protein catalyst, i.e. enzyme, origin-of-life theorists believed the central piece of the puzzle of life had been found.
Enzyme creation normally requires RNA- or DNA-type templates, but these nucleotides themselves need enzymes to function. If RNA could be cut and spliced without the aid of proteins, however, there was a basis for self-replication: RNA molecules assisting each other, and eventually evolving into life as we know it.
The concept of a primordial replicator is at the center of most origin theories. So it seemed only a matter of time before researchers would show how the components of RNA became available under prebiotic conditions, and how they connected up.
But it has proven far from easy, and most researchers now agree that RNA itself is too complex and fragile to have formed entirely from abiotic processes. They are now looking for a simpler replicator, a pre-RNA, with RNA coming on the scene later.
Nonetheless, some scientists, including nucleic acid chemist Robert Shapiro of New York University, are convinced that this whole approach is misguided. Making his case before audience at The New York Academy of Sciences (the Academy) in February, Shapiro pointed to a growing number of skeptics who wonder if life started with a replicator at all.
At Least 3.5 Billion Years Old
It’s too difficult to conceive, Shapiro said, of all these sensitive organic ingredients coming together, hanging together and creating a replicator complex enough to build proteins –– and eventually cells –– under the earth’s early conditions. And, given the evidence that cellular life on earth is at least 3.5 billion years old, less time was available than once was imagined.
If one were to put pre-RNA ingredients together in a laboratory, without the helping hand of a chemist, and cook them with the other chemicals that were likely present on the early earth, Shapiro said, the outcome would be “a tarry mess.” It would be a near-miracle for these components to come together spontaneously to form a functioning replicator.
Shapiro prefers the work of a growing number of researchers looking at the possibility that small organic and inorganic molecules could organize themselves into self-catalyzing metabolic webs. These webs could recruit components into an increasingly complex organic matrix of reactions, and the simple compartments that held them could reproduce by the simple act of splitting. If a suitable energy source were available to drive the process, such systems could have multiplied and evolved. Accurate residue-by-residue replication would be an advance that was introduced later in evolution.
Primordial Laboratories
Günter Wächtershäuser has formulated scenarios involving molecular adhesion on the surface of iron pyrite, drawing chemicals such as iron, nickel and sulfur, and energy from deep sea vents. David Deamer, Doron Lancet and others have proposed that the chemistry of lipid vesicles –– growing and splitting and carrying around water and small molecules –– could have been the environment. These “little bags of dirty water” might have been primordial laboratories for the emergence of early life.
Shapiro urged support for these new ideas, many testable in the laboratory. He also urged support for space missions that might find environments that harbor, or once harbored, primordial life. We might glimpse this process at work, he suggested, or find evidence of primitive life forms. Most important, says Shapiro, we might prove that the emergence of life from non-living conditions is natural and common, that self-organizing principles exist in prebiotic chemistry.
Dr. Shapiro has written acclaimed books on this topic for the general reader, including, most recently, Planetary Dreams: The Quest to Discover Life Beyond Earth.
Also read: Cosmic Chemistry and the Origin of Life