An international team has succeeded in cloning one of tea's genes for making caffeine—a step toward creating decaf tea and coffee plants.
The gene, TCS1, codes for caffeine synthase, the enzyme that controls the final two steps in the molecule's four-step synthesis, explain Misako Kato and Hiroshi Ashihara of Ochanomizu University in Tokyo and their colleagues in the Aug. 31 Nature. When the researchers finally cloned TCS1, they found it had little similarity to other genes.
Important as caffeine has been to humanity—inspiring cuisine, commerce, and poetry, not to mention preventing the collapse of the industrialized world on Monday mornings—biologists have only recently begun unraveling nature's own caffeine synthesis.
Some 40 species of plants make caffeine, but "no function is really known" for the chemical, notes coauthor Alan Crozier of the University of Glasgow in Scotland. He acknowledges the theories that caffei