Then he figured out what had gone haywire in the biochemical pathway that leads to the production of the UV-absorbing compound. It was F5H that his mutant plants lacked. Without F5H the plants couldn't create the UV-absorber. When F5H is missing or scarce, as it is in Chapple's UV-sensitive mutants, they mostly make guaiacyl lignin, the type that is hard to degrade. Chapple knew that no manufacturers would beat a path to his door for this discovery.
Nobody wants trees that are harder to process or plants that are harder to digest.
On the other hand, thought Chapple, maybe he could use what he had learned about F5H to increase, rather than decrease, the levels of the F5H enzyme. Plants with more of the F5H enzyme might produce more of the easily degradable syringyl lignin. They also found that plants rich in syringyl lignin grew and looked exactly like normal Arabidopsis . The genes responsible for the transformation worked similarly in tobacco plants, which led Chapple to believe they will work in trees, alfalfa, corn, grass and other plants and spurred him to pursue a patent. Patents didn't appear in even his wildest dreams when Chapple started working on UV-protection in Arabidopsis .