Researchers at the Massachusetts Institute of Technology (MIT) have
engineered plants that give off dim light. The MIT team used luciferase, the
enzyme that gives fireflies their glowing light. Luciferase acts on the
molecule luciferin, causing it to emit light. Another molecule called
co-enzyme A helps the process by removing a reaction byproduct that can
inhibit luciferase activity.
These three components were packed into a different type of nanoparticle
carrier. The nanoparticles help each component to get to the specific part
of the plant, and also prevent the components from reaching concentrations
that could be toxic to plants.
The researchers used silica nanoparticles to carry luciferase, and used
slightly larger particles of the polymers PLGA and chitosan to carry
luciferin and coenzyme A, respectively. The plants were immersed in the
solution and then exposed to high pressure, allowing the particles to enter
the leaves through the stomata. Early efforts at the start of the project
yielded plants that could glow for about 45 minutes, which has since
improved to 3.5 hours.