Chemical Reactions, CR 4: Driving Reactions (HS), HE 1: Earth's History (MS), HE 2: Early Earth (HS), History of Earth, Physical Science, S&P 4: Molecule Traits (HS), Structure & Properties of Matter

Beaming Pyrimidines Part 5

Mechanisms for the formation of thymine under astrophysical conditions and implications for the origin of life

SUMMARY: This article talks about different ways thymine can form under the conditions given in Part 4 of the Beaming Pyrimidines series. By adding hydroxyl and methyl groups to pyrimidine and beaming the mixture, thymine can form. The role of water in these mixes both promotes and restricts the production of thymine. If some of these molecules did originate from asteroids in space, this series of experiments supports the RNA world hypothesis in that uracil was easier to form and was more abundant in these asteroid-like conditions simulated in the lab.

LESSON COMMENTS: This article is quite dense on the organic chemistry so I would focus on the conclusion for younger students. Feel free to take a stab at the different routes of thymine formation with your more advanced students though!
An interesting topic from this series is the RNA world and the formation of replicating macromolecules. What came first, the enzyme or the nucleic acid?

Bera, P. P., Nuevo, M., Materese, C. K., Sandford, S. A., & Lee, T. J. (2016). Mechanisms for the formation of thymine under astrophysical conditions and implications for the origin of life. The Journal of chemical physics, 144(14), 144308.