title: 5-Enolpyruvylshikimate-3-phosphate synthase from Staphylococcus aureus is insensitive to glyphosate.
abstract: The enzyme 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) catalyzes the penultimate step of the shikimate pathway, and is the target of the broad-spectrum herbicide glyphosate. Kinetic analysis of the cloned EPSPS from Staphylococcus aureus revealed that this enzyme exerts a high tolerance to glyphosate, while maintaining a high affinity for its substrate phosphoenolpyruvate. Enzymatic activity is markedly influenced by monovalent cations such as potassium or ammonium, which is due to an increase in catalytic turnover. However, insensitivity to glyphosate appears to be independent from the presence of cations. Therefore, we propose that the Staphylococcus aureus EPSPS should be classified as a class II EPSPS. This research illustrates a critical mechanism of glyphosate resistance naturally occurring in certain pathogenic bacteria.
authors.affiliation: Department of Medicinal Chemistry, University of Kansas, 4040a Malott Hall, Lawrence, KS 66049, USA.
authors.forename: Melanie A
authors.initials: MA
authors.lastname: Priestman
authors.forename: Todd
authors.initials: T
authors.lastname: Funke
authors.forename: Inder M
authors.initials: IM
authors.lastname: Singh
authors.forename: Scott S
authors.initials: SS
authors.lastname: Crupper
authors.forename: Ernst
authors.initials: E
authors.lastname: Schönbrunn
mesh_terms: D051229:3-Phosphoshikimate 1-Carboxyvinyltransferase; D019883:Alkyl and Aryl Transferases / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D001483:Base Sequence; D003001:Cloning, Molecular; D017931:DNA Primers; D004591:Electrophoresis, Polyacrylamide Gel; D005998:Glycine / Q000031:analogs & derivatives* / Q000494:pharmacology*; D007700:Kinetics; D016133:Polymerase Chain Reaction; D013211:Staphylococcus aureus / Q000201:enzymology*; D000097797:Glyphosate
chemical_list: D051229:3-Phosphoshikimate 1-Carboxyvinyltransferase; D019883:Alkyl and Aryl Transferases; D017931:DNA Primers; D005998:Glycine; D000097797:Glyphosate