title: Safety evaluation of the phosphinothricin acetyltransferase proteins encoded by the pat and bar sequences that confer tolerance to glufosinate-ammonium herbicide in transgenic plants.
abstract: Transgenic plant varieties, which are tolerant to glufosinate-ammonium, were developed. The herbicide tolerance is based upon the presence of either the bar or the pat gene, which encode for two homologous phosphinothricin acetyltransferases (PAT), in the plant genome. Based on both a review of published literature and experimental studies, the safety assessment reviews the first step of a two-step-approach for the evaluation of the safety of the proteins expressed in plants. It can be used to support the safety of food or feed products derived from any crop that contains and expresses these PAT proteins. The safety evaluation supports the conclusion that the genes and the donor microorganisms (Streptomyces) are innocuous. The PAT enzymes are highly specific and do not possess the characteristics associated with food toxins or allergens, i.e., they have no sequence homology with any known allergens or toxins, they have no N-glycosylation sites, they are rapidly degraded in gastric and intestinal fluids, and they are devoid of adverse effects in mice after intravenous administration at a high dose level. In conclusion, there is a reasonable certainty of no harm resulting from the inclusion of the PAT proteins in human food or in animal feed.
authors.affiliation: Bayer CropScience SA, Sophia Antipolis, France. corinne.herouet@bayercropscience.com
authors.forename: Corinne
authors.initials: C
authors.lastname: Hérouet
authors.forename: David J
authors.initials: DJ
authors.lastname: Esdaile
authors.forename: Bryan A
authors.initials: BA
authors.lastname: Mallyon
authors.forename: Eric
authors.initials: E
authors.lastname: Debruyne
authors.forename: Arno
authors.initials: A
authors.lastname: Schulz
authors.forename: Thomas
authors.initials: T
authors.lastname: Currier
authors.forename: Koen
authors.initials: K
authors.lastname: Hendrickx
authors.forename: Robert-Jan
authors.initials: RJ
authors.lastname: van der Klis
authors.forename: Dominique
authors.initials: D
authors.lastname: Rouan
mesh_terms: D000123:Acetyltransferases / Q000235:genetics* / Q000633:toxicity*; D000595:Amino Acid Sequence; D000613:Aminobutyrates / Q000494:pharmacology*; D000818:Animals; D001483:Base Sequence; D004361:Drug Tolerance; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D005750:Gastric Juice / Q000187:drug effects / Q000378:metabolism; D005798:Genes, Bacterial; D005818:Genetic Engineering; D006540:Herbicides / Q000494:pharmacology*; D006801:Humans; D051379:Mice; D008815:Mice, Inbred Strains; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics*; D030821:Plants, Genetically Modified / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D018675:Toxicity Tests
chemical_list: D000613:Aminobutyrates; D006540:Herbicides; D010940:Plant Proteins; C003121:phosphinothricin; D000123:Acetyltransferases; C056243:phosphinothricin N-acetyltransferase