All foods, even natural ones, are made up of chemicals. But natural foods don't have to list their ingredients. So it's often assumed they're

Transcription

1 All foods, even natural ones, are made up of chemicals. But natural foods don't have to list their ingredients. So it's often assumed they're chemical-free. In fact, the ordinary orange is a miniature chemical factory. And the good old potato contains arsenic among its more than 150 ingredients. This doesn't mean natural foods are dangerous. If they were, they wouldn't be on the market. The same is true of manmade foods. All man-made foods are tested for safety. And they often provide more nutrition, at a lower cost, than natural foods. They even use many of the same chemical ingredients. So you see, there really isn't much difference between foods made by Mother Nature and those made by man. What's artificial is the line drawn between them. Without chemicals, life itself would be impossible.

2 The New Monsanto Glyphosate was first discovered to have herbicidal activity in 1970 by John E. Franz, while employed by Monsanto (trade name - Roundup) HO O N H O P OH OH

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4 Genes Monsanto scientists genetically modify a plant cell in 1982 Agro bacterium strain CP4 (CP4 EPSPS) that was resistant to glyphosate. This CP4 EPSPS gene was cloned and transected into soybeans Agricultural crops tolerant to the herbicide glyphosate(n-phosphonomethyl-glycine) have been planted on increasing numbers of hectares since the introduction of the glyphosate-tolerant soybean event in 1996 (Padgette et al., 1996; marketed under the Roundup Ready brand1). CROP SCIENCE, VOL. 44, (2005)

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6 Round ready crops Roundup Ready soybeans (1996) Roundup Ready corn (1998) Roundup Ready sorghum Roundup Ready canola Roundup Ready alfalfa Roundup Ready cotton Roundup Ready sugarbeets Roundup Ready wheat (paused)

7 In % of soybeans, 61% of cotton, and 26% of corn planted in the United States in 2005 were glyphosate-tolerant varieties lingering concerns about the potential health and environmental effects of genetically modified organisms (GMOs) have limited the acceptance of such seed lines and food products, particularly in Europe and Japan.

8 Other genes Three transgenes are used with these crops. A gene (CP4) encoding a GR form of EPSPS from Agrobacterium sp. was found to be very effective at producing GRCs (Padgette et al., 1996a). A gene from the microbe Ochrobactrum anthropi that encodes a glyphosate-degrading enzyme (glyphosate oxidase, GOX) is used in GR canola with CP4 EPSPS (Padgette et al., 1996a). GOX degrades glyphosate to glyoxylate, an ubiquitous and safe natural product, and aminomethylphosphonate (AMPA). A form of GR EPSPS from maize was produced by sitedirected mutagenesis for use as a transgene in maize (Dill, 2005).

9 Bean monopoly?

10 Monsanto sues farmers Monsanto sues farmers over seeds Monsanto has whole department to enforce its seed patents and licensing agreements (75 employees and >$10M) Since 1997, Monsanto has filed lawsuits 90 times in 25 states against 147 farmers and 39 agriculture companies

11 One of many examples Youtube

12 Molecular basis for the herbicide resistance of Roundup Ready crops Todd Funke, Huijong Han, Martha L. Healy-Fried, Markus Fischer, and Ernst Schonbrunn Department of Medicinal Chemistry, University of Kansas, Lawrence, KS 66045; and Department of Organic Chemistry and Biochemistry, Technical University Munich, D Garching, Germany Edited by Brian W. Matthews, University of Oregon, Eugene, OR, and approved July 12, 2006 (received for review May 3, 2006) PNAS August 29, 2006 vol. 103 no. 35

13 Fig. 1. Key kinetic properties of CP4 EPSP synthase. (A) The reaction catalyzed by EPSP synthase. (B) The activity of CP4 EPSP synthase depends strongly on the presence of cations, such as NH4, Rb, andk. (Inset) Activation by K is saturable with an apparent dissociation constant of 25mM.(C) IC50 studies with wild-type CP4 EPSP synthase ( ), Ala-100 Gly CP4 EPSP synthase (OE), and wild-type E. coli EPSP synthase (F) reveal that CP4 EPSP synthase is inhibited only by high millimolar concentrations of glyphosate (IC5011 mm). The Ala-100 Gly mutant CP4 EPSP synthase is approximately two orders of magnitude more sensitive to glyphosate (IC M). The E. coli enzyme is inhibited by even lower glyphosate concentrations (IC M).

14 (Left) Unliganded CP4 EPSP synthase exists in an open conformation. (Right) Upon interaction with S3P, the enzyme undergoes a large conformational change to a closed state. Shown in orange is a loop spanning residues , which is highly flexible in the open conformation but becomes ordered in the closed conformation. This loop contains the strictly conserved EPSP synthase residues Glu-354 and Arg-357,which are involved in PEPglyphosate binding. Monovalent cations may influence the conformation of this loop and facilitate binding of PEP.

15 Fig. 4. Two distinct conformations of glyphosate. Displayed are the electron densities, contoured at 3, derived from 1Fo 1Fc Fourier syntheses to 1.7-Å resolution, omitting the model of glyphosate during the refinement of the ternary complexes of CP4 EPSP synthase (Left) and Ala-100 Gly CP4 EPSP synthase (Right). (Right) The conformation of glyphosate upon interaction with the Ala-100 Gly CP4 EPSP synthase is identical to the one observed in the E. coli or Str. pneumoniae enzymes. (Left) With an Ala residue in position 100, the glyphosate molecule is 0.6 Å shorter, mainly because of a rotation around the CON bond next to the carboxyl group

16 It is conceivable that a single Ala for Gly substitution in the active site of other class II EPSP synthases will confer resistance to glyphosate

17 Glyphosate resistance in several species has been documented in Georgia, North Carolina, Tennessee and Arkansas Glyphosate resistant Palmer amaranth (a pigweed species)

18 In June 2007, Monsanto acquired Delta & Pine Land Company, a company that had patented a seed technology nicknamed "Terminator". This technology, has not been used commercially, produces plants that have sterile seeds so they do not flower or grow fruit after the initial planting, requiring customers to purchase seed from Monsanto for every planting in which they use Monsanto seed varieties.

19 GMOs What for dinner?