title: Safety evaluation of the double mutant 5-enol pyruvylshikimate-3-phosphate synthase (2mEPSPS) from maize that confers tolerance to glyphosate herbicide in transgenic plants.
abstract: Glyphosate tolerance can be conferred by decreasing the herbicide's ability to inhibit the enzyme 5-enol pyruvylshikimate-3-phosphate synthase, which is essential for the biosynthesis of aromatic amino acids in all plants, fungi, and bacteria. Glyphosate tolerance is based upon the expression of the double mutant 5-enol pyruvylshikimate-3-phosphate synthase (2mEPSPS) protein. The 2mEPSPS protein, with a lower binding affinity for glyphosate, is highly resistant to the inhibition by glyphosate and thus allows sufficient enzyme activity for the plants to grow in the presence of herbicides that contain glyphosate. Based on both a review of published literature and experimental studies, the potential safety concerns related to the transgenic 2mEPSPS protein were assessed. The safety evaluation supports that the expressed protein is innocuous. The 2mEPSPS enzyme does not possess any of the properties associated with known toxins or allergens, including a lack of amino acid sequence similarity to known toxins and allergens, a rapid degradation in simulated gastric and intestinal fluids, and no adverse effects in mice after intravenous or oral administration (at 10 or 2000 mg/kg body weight, respectively). In conclusion, there is a reasonable certainty of no harm resulting from the inclusion of the 2mEPSPS protein in human food or in animal feed.
authors.affiliation: Bayer CropScience SA, BP153, 355 rue Dostoïevski, 06130 Sophia Antipolis, France. corinne.herouet-guicheney@bayercropscience.com
authors.forename: Corinne
authors.initials: C
authors.lastname: Herouet-Guicheney
authors.forename: David
authors.initials: D
authors.lastname: Rouquié
authors.forename: Martine
authors.initials: M
authors.lastname: Freyssinet
authors.forename: Thomas
authors.initials: T
authors.lastname: Currier
authors.forename: Aris
authors.initials: A
authors.lastname: Martone
authors.forename: Junguo
authors.initials: J
authors.lastname: Zhou
authors.forename: Elizabeth E M
authors.initials: EE
authors.lastname: Bates
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Ferullo
authors.forename: Koen
authors.initials: K
authors.lastname: Hendrickx
authors.forename: Dominique
authors.initials: D
authors.lastname: Rouan
mesh_terms: D051229:3-Phosphoshikimate 1-Carboxyvinyltransferase / Q000235:genetics / Q000378:metabolism / Q000633:toxicity*; D000595:Amino Acid Sequence; D000818:Animals; D003257:Consumer Product Safety; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D005260:Female; D030841:Food, Genetically Modified / Q000633:toxicity*; D005998:Glycine / Q000031:analogs & derivatives* / Q000633:toxicity; D006540:Herbicides / Q000633:toxicity*; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D009154:Mutation; D030821:Plants, Genetically Modified; D055550:Protein Stability; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism / Q000633:toxicity; D017386:Sequence Homology, Amino Acid; D023382:Toxicity Tests, Acute; D003313:Zea mays / Q000187:drug effects / Q000201:enzymology / Q000235:genetics*; D000097797:Glyphosate
chemical_list: D051229:3-Phosphoshikimate 1-Carboxyvinyltransferase; D005998:Glycine; D006540:Herbicides; D011994:Recombinant Proteins; D000097797:Glyphosate