The Mystery of Gardenia's Fragrance: A Tiny Change Makes a Big Difference

Did you know that plants make special chemicals called terpenoids to help them survive tough conditions? Gardenia, famous for its sweet smell, is full of these volatile terpenoids. Scientists recently figured out how Gardenia makes its unique scent. They found six key enzymes called terpene synthases (TPS) that help produce these smelly compounds. Two of these enzymes, GjTPS1 and GjTPS2, are almost identical, but they pick different starting materials. How do they do it? Scientists used smart computers and made tiny changes in these enzymes to find out. They discovered that a single tiny part of the enzyme, way outside where the action happens, acts like a switch. This little switch changes what the enzyme likes to work with! By comparing these enzymes with others from coffee plants and other plants, scientists learned that Gardenia's TPS genes have grown in number through a process called duplication. This means Gardenia has more of these enzymes than other plants. This new finding is exciting because it shows that even tiny, seemingly useless parts of enzymes can have big effects. Understanding this could help make even better Gardenia plants or design new enzymes to make specific smells.