title: Molecular basis for the glyphosate-insensitivity of the reaction of 5-enolpyruvylshikimate 3-phosphate synthase with shikimate.
abstract: The shikimate pathway enzyme 5-enolpyruvyl shikimate-3-phosphate synthase (EPSP synthase) has received attention in the past because it is the target of the broad-spectrum herbicide glyphosate. The natural substrate of EPSP synthase is shikimate-3-phosphate. However, this enzyme can also utilize shikimate as substrate. Remarkably, this reaction is insensitive to inhibition by glyphosate. Crystallographic analysis of EPSP synthase from Escherichia coli, in complex with shikimate/glyphosate at 1.5 Angstroms resolution, revealed that binding of shikimate induces changes around the backbone of the active site, which in turn impact the efficient binding of glyphosate. The implications from these findings with respect to the design of novel glyphosate-insensitive EPSP synthase enzymes are discussed.
authors.affiliation: Department of Medicinal Chemistry, University of Kansas, 4040a Malott Hall, Lawrence, 66045, USA.
authors.forename: Melanie A
authors.initials: MA
authors.lastname: Priestman
authors.forename: Martha L
authors.initials: ML
authors.lastname: Healy
authors.forename: Todd
authors.initials: T
authors.lastname: Funke
authors.forename: Andreas
authors.initials: A
authors.lastname: Becker
authors.forename: Ernst
authors.initials: E
authors.lastname: Schönbrunn
mesh_terms: D051229:3-Phosphoshikimate 1-Carboxyvinyltransferase / Q000737:chemistry* / Q000187:drug effects / Q000378:metabolism; D001665:Binding Sites; D003461:Crystallography; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D004926:Escherichia coli / Q000201:enzymology; D005998:Glycine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000494:pharmacology; D011487:Protein Conformation; D012765:Shikimic Acid / Q000737:chemistry / Q000378:metabolism*; D000097797:Glyphosate
chemical_list: D051229:3-Phosphoshikimate 1-Carboxyvinyltransferase; D004791:Enzyme Inhibitors; D005998:Glycine; D012765:Shikimic Acid; D000097797:Glyphosate