Sequencing Of Coffee Genome Reveals Secrets Of Caffeine Development

Chuck Bednar for – Your Universe Online
By sequencing the genome of the coffee plant, an international team of researchers has discovered genetic secrets that could enable them to create new varieties of coffee that taste better, have varied levels or caffeine, or are better able to survive drought conditions and diseases.
In addition, Philippe Lashermes, a researcher at the French Institute of Research for Development (IRD), and his colleagues discovered that the coffee plant developed caffeine-linked genes independently and did not inherit them from a common ancestor. Their findings are detailed in Thursday’s online edition of the journal Science.
According to the researchers, they decided to sequence the coffee genome because it is “one of the most important crops on Earth,” with 8.7 million tons of coffee produced last year and over 2.25 billion cups of the beverage consumed on a daily basis. They selected the species Coffea canephora as it displayed a conserved chromosomal gene order among asterid angiosperms, and because they were able to generate a high-quality draft genome of the plant.
“Coffee is as important to everyday early risers as it is to the global economy. Accordingly, a genome sequence could be a significant step toward improving coffee,” Lashermes, one of the principal authors of the study, said in a statement. “By looking at the coffee genome and genes specific to coffee, we were able to draw some conclusions about what makes coffee special.”
After sequencing the Coffea canephora genome, the study authors examined how its genetic composition differed from other types of plants. In comparison to several other species, including grapes and tomatoes, they discovered larger families of genes associated with the production of alkaloid and flavonoid compounds in coffee plants – compounds with contribute to traits such as the aroma of the coffee and the bitterness of the beans.
Furthermore, they discovered that coffee has an expanded group of enzymes known as N-methyltransferases, which are involved in caffeine production. After examining these enzymes more closely, the researchers learned that they were more closely related to other genes in the coffee plant than to caffeine enzymes found in tea and chocolate – a discovery which suggests caffeine production developed independently in coffee plants, since the enzymes would have been more similar between species if they had been inherited from a common ancestor.
“The coffee genome helps us understand what’s exciting about coffee – other than that it wakes me up in the morning,” said Victor Albert, professor of biological sciences at the University at Buffalo and co-principle author. “By looking at which families of genes expanded in the plant, and the relationship between the genome structure of coffee and other species, we were able to learn about coffee’s independent pathway in evolution.”
Albert told Reuters reporter Will Dunham that the coffee genome was about as large as the average plant genome, and had approximately 25,500 genes responsible for various proteins. He also suggested that coffee plants might have started producing caffeine in order to entice pollinators to return, or to prevent herbivorous insects from eating their leaves.
The study was funded by the French National Research Agency; the Australian Research Council; the Natural Sciences and Engineering Research Council of Canada; the CNR-ENEA Agrifood Project of Italy; the Funding Authority for Studies and Projects (FINEP Qualicafe) of Brazil; the National Institutes of Science and Technology (INCT Cafe) of Brazil; the US National Science Foundation (NSF); the College of Arts and Science at the University at Buffalo; and in-kind support by scientists at Nestle’s research and development center in France.
Keurig K130/B130 Brewing System