If you have an ACS member number, please enter it here so we can link this account to your membership. (optional)

ACS values your privacy. By submitting your information, you are gaining access to C&EN and subscribing to our weekly newsletter. We use the information you provide to make your reading experience better, and we will never sell your data to third party members.


Biological Chemistry

How An Origin-of-Life Idea Stacks Up

Paired strands of nucleotides lend support to an idea first proposed by Francis Crick

by Carmen Drahl
December 24, 2012 | A version of this story appeared in Volume 90, Issue 52

The question of how nucleic acids assembled into DNA and RNA polymers, without enzymes, still roils researchers who think about life’s origins on Earth. Some think a clue lies in a 40-year-old idea from Francis Crick—that Watson-Crick base pairs, made with one purine and one pyrimidine base, might have evolved from purine-purine pairs. Evidence exists to support that idea: Purines are products of model prebiotic reactions, and purine-purine pairs can be as stable as Watson-Crick pairs. Now, a study with small paired strands of nucleotides throws more support Crick’s way (ChemBioChem, DOI: 10.1002/cbic.201200601). With polyacrylamide gels and a chemical activating agent, Elizabeth Kuruvilla, Gary B. Schuster, and Nicholas V. Hud of Georgia Institute of Technology measured how well different strands polymerized. Sure enough, all-purine strands performed better than counterparts containing both purines and pyrimidines. Chemists know that stacking interactions between bases help nucleotide polymerizations along and that purines’ bigger surface area makes them better stackers. The team thinks these concepts explain their results. They propose that a primitive information polymer, perhaps an ancestor of RNA, would have had optimal base-stacking properties.


This article has been sent to the following recipient:

Chemistry matters. Join us to get the news you need.