Herbicide Project
From WikidChem
Atrazine is the most popularly used herbicide in the U.S. In 2003, 77 million pounds of atrazine were used in the U.S. Several European countries have banned its use; currently the EPA says that atrazine is safe for humans. However, this is hotly debated.
Herbicides have traditionally been discovered via a trial and error process. In fact, when atrazine and DCMU were first discovered, their mode of action was unknown. It was only known that they were effective at killing plants. Later reasearch would show that both atrazine and DCMU work by competeively binding to the Qb bining pocket in Photosystem II. This prevents electron transfer from Qa to Qb and effectively stalls photosynthesis, eventually leading to death of the plant. Many other herbicides follow this same mode of action. Currently, definitive information on how these herbicides bind is unaviailble. The goal of this project is to elucidate the mechanism by which these herbicides bind; this will hopefully provide insight for future research of novel herbicides with less toxic effects than the ones currently available.
This shows atrazine binding in the Qb pocket of bacterial photosystem II. This interaction was calculated with the Induced Fit Docking that is provided by Schrodinger. In the figure, three hydrogen bonds between the herbicide and the protein can be seen as dotted yellow lines.
