Together, they’ve created a new breed of petunia that can change from white to red, and back again, whenever you want. The science behind it is actually fairly straightforward, too. Here’s how Braun and Havens describe it on their website:
“Most flower color is the result of anthocyanins, small molecules naturally produced in large quantities by a biosynthetic pathway. In white flowers, this pathway is often broken – an enzyme doesn’t work as expected and the flower cannot produce anthocyanins. If we know what enzyme isn’t working, we can use biotechnology to fix the broken pathway by expressing the enzyme.”
“Each section of the flower has a specific set of instructions in its DNA on which genes to use. We can use these instructions to re-introduce the enzyme in a pretty pattern – across the whole flower, in a star shape, around the edge of the flower, and more. We can also express genes under certain conditions in what is known as ‘regulated gene expression’. One example is temperature: at low temperatures, the enzyme is not expressed; at high temperatures, it is.
We have given the plant the following set of instructions: If a small molecule is present, fix the pathway. With these instructions in place, you can change the flower color according to your mood.”
In the case of the white-to-red petunia, Braun and Havens chose to use ethanol as the trigger molecule. Therefore, all you need to do is water the plant with a diluted ethanol solution (they recommend old beer), and it will change from white to red in 24 hours. When you get tired of red, just give the plant regular water, and it’ll transition back to white.
And that’s not all. The white-to-red petunia is just one of the company’s many flower-hacking projects. They’re also working on a flower that continuously changes from red to purple to blue throughout the day, as well as one that smells like vanilla.
To raise money needed for further development, the duo have launched an Indiegogo campaign, where they’re currently offering some of their amazing flowers to backers. For a pledge of 99 bucks, Revolution Bio will send you three color-changing petunias you can plant in your garden.
