Interaction of the Herbicide Glyphosate with Its Target Enzyme 5-Enolpyruvylshikimate 3-Phosphate Synthase in Atomic Detail

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 98; no. 4; pp. 1376 - 1380
• Main Authors: Schönbrunn, Ernst, Eschenburg, Susanne, Shuttleworth, Wendy A., Schloss, John V., Amrhein, Nikolaus, Jeremy N. S. Evans, Kabsch, Wolfgang
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences 13.02.2001; National Acad Sciences; The National Academy of Sciences
• Subjects: 3-Phosphoshikimate 1-Carboxyvinyltransferase; Alkyl and Aryl Transferases - chemistry; Amino acids; Binding Sites; Biochemistry; Biological Sciences; Drug resistance; Enzyme Inhibitors - chemistry; Enzymes; Formates - chemistry; Glycine - analogs & derivatives; Glycine - chemistry; Glyphosate; Herbicides; Herbicides - chemistry; Models, Molecular; Molecular Structure; Phosphates - chemistry; Phosphoenolpyruvate - chemistry; Protein Structure, Tertiary; X-Ray Diffraction
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.98.4.1376

Biosynthesis of aromatic amino acids in plants, many bacteria, and microbes relies on the enzyme 5-enolpyruvylshikimate 3-phosphate (EPSP) synthase, a prime target for drugs and herbicides. We have identified the interaction of EPSP synthase with one of its two substrates (shikimate 3-phosphate) and with the widely used herbicide glyphosate by x-ray crystallography. The two-domain enzyme closes on ligand binding, thereby forming the active site in the interdomain cleft. Glyphosate appears to occupy the binding site of the second substrate of EPSP synthase (phosphoenol pyruvate), mimicking an intermediate state of the ternary enzyme·substrates complex. The elucidation of the active site of EPSP synthase and especially of the binding pattern of glyphosate provides a valuable roadmap for engineering new herbicides and herbicide-resistant crops, as well as new antibiotic and antiparasitic drugs.