An international team of scientists has sequenced the genome of the yerba mate (Ilex paraguariensis), an economically important crop marketed for the elaboration of mate, the third-most widely consumed caffeine-containing infusion worldwide.
Vignale et al. report the first draft genome sequence for yerba mate and provide convincing evidence for the identity and characteristics of enzymes for caffeine biosynthesis. Image credit: Ilosuna / CC BY-SA 3.0.
The yerba mate is a caffeinated tree species endemic to the subtropical rainforests of South America.
The dried leaves and twigs of this dioecious evergreen are used to prepare a traditional infusion named mate, or chimarrão, widely consumed around the world.
Approximately 300,000 hectares are cultivated with this tree crop, with Argentina responsible for 80% of worldwide production.
The mate infusion has been shown to have numerous beneficial effects in humans including as an antioxidant, antidiabetic, as well as central nervous system stimulant, among others.
Although its stimulant properties are mostly related to caffeine content, little is known about the genetic and biochemical mechanisms of how yerba mate synthesizes this, or any, of its important metabolites.
“We discovered that an ancestor of yerba had duplicated its genome approximately 50 million years ago,” said Dr. Federico Vignale, a researcher at the European Molecular Biology Laboratory.
“This ancestral duplication may have been key in the evolution of its metabolic complexity, allowing it to synthesise a wide range of bioactive compounds, such as terpenes, flavonoids, phenols, and xanthines, known for their antioxidant, anti-diabetic, and nervous system stimulant properties.
“Of all these compounds, my interest focused on caffeine.”
The researchers found that the yerba mate genome has a total length of 1.06 billion base pairs and contains at least 53,390 protein-coding genes.
They also were able to determine the genes and biochemical pathway responsible for caffeine biosynthesis in this species.
“Caffeine is produced by several unrelated plant species, such as yerba mate and coffee, through similar metabolic pathways for its biosynthesis,” they said.
“Yet, we discovered that the genes involved in these pathways evolved independently.”
“We came to understand in detail that the genes do not have a common ancestor, but come from separate origins, and that both yerba mate and coffee came to have caffeine biosynthesis by evolving along convergent pathways,” said Dr. Adrián Turjanski, a researcher at the University of Buenos Aires.
The parallel evolution of caffeine synthesis in yerba mate and coffee led scientists to suspect it plays a crucial role in plant survival, potentially functioning as a defense mechanism.
“By reading the genome you would know how to intervene and modify the plant,” Dr. Turjanski said.
“One could propose making it richer in certain characteristics, for example, a decaffeinated yerba mate, or one that is better adapted to other lands, and thus expand its cultivation.”
The results were published online in the journal eLife.
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Federico A. Vignale et al. 2025. Yerba mate (Ilex paraguariensis) genome provides new insights into convergent evolution of caffeine biosynthesis. eLife 14: e104759; doi: 10.7554/eLife.104759