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Safety Assessment of the Neomycin Phosphotransferase II (NPTII) Protein

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Abstract

Two approaches were used to assess the safety of the NPTII protein for human consumption using purified E. coli produced NPTII protein that was shown to be chemically and functionally equivalent to the NPTII protein produced in genetically engineered cotton seed, potato tubers and tomato fruit. The NPTII protein was shown, as expected, to degrade rapidly under simulated mammalian digestive conditions. An acute mouse gavage study confirmed that the NPTII protein caused no deleterious effects when administered by gavage at a cumulative target dosage of up to 5000 mg/kg of body weight. This dosage correlates to at least a million fold safety factor relative to the average daily consumption of potato or tomato, assuming all the potatoes or tomatoes consumed contained the NPTII protein. These results, along with previously published information, confirm that ingestion of genetically engineered plants expressing the NPTII protein poses no safety concerns.

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References

  1. 1

    Gasser, C.S. and Fraley, R.T. 1989. Genetically engineering plants tor crop improvement. Science 244: 1293–1299.

  2. 2

    Casper, R. and Landsman, J. 1992. Summary of results, p. 12–14. In: The Biosafety Results Of Field Tests Of Genetically Modified Plants And Microorganisms. Casper, R. and Landsmann, J., Biologische Bundesanstalt fur Land- und Forstwirtschaft, Braunschweig, Germany.

  3. 3

    Animal and Plant Health Inspection Service. 1992. Proposed interpretive ruling in connection with Calgene, Inc. petition for determination of regulatory status of Flavr Savr® Tomato. Fed. Reg. 57: 31170.

  4. 4

    Calgene, Inc. 1990. Request for advisory opinion KanR gene: safety and use in the production of genetically engineered plants. FDA Docket Number: 90A-0416.

  5. 5

    Calgene, Inc. 1993. Food additive petition for the APH(3′)II as a processing aid. FDA docket number: 93F-0232.

  6. 6

    Nap, J.P., Bijvoet, J. and Stikema, W.J. 1992. Biosafety of kanamycin-resistant transgenic plants: an overview. Transgenic Crops 1: 239–249.

  7. 7

    Flavell, R.B., Dart, E., Fuchs, R.L. and Fraley, R.T. 1992. Selectable marker genes: safe for plants? Bio/Technology 10: 141–144.

  8. 8

    Guyton, A.C. 1981. Digestion and absorption in the gastointestinal tract, p. 816–826. In Textbook of Medicinal Physiology, 6th Ed. W.B. Saunders Co., Philadelphia.

  9. 9

    Nielson, S.S. 1988. Degradation of bean proteins by endogenous and exogenous proteases—a review. Cereal Chem. 65: 435–442.

  10. 10

    Marquez, U.M.L. and Lajolo, F.M. 1981. Composition and digestibility of albumin, globulins, and glutelins from Phaseolus vulgaris. J. Agric. Food Chem. 29: 1068–1074.

  11. 11

    Zikakis, J.P., Rzucidlo, S.J. and Biasotto, N.O. 1977. Persistence of bovine milk xanthine oxidase activity. J. Dairy Science 60: 533–541.

  12. 12

    Tilch, C. and Elias, P.S. 1984. Investigation of the mutagenicity of ethylphenyl-glycidate. Mutation Research 138: 1–8.

  13. 13

    Akeson, W.R. and Stahmann, M.A. 1964. A pepsin pancreatin digest index of protein quality evaluation. J. Nutrition 83: 257–261.

  14. 14

    Fuller, M.F. (Ed.). 1991. In Vitro Digestion for Pigs and Poultry. C.A.B. International, Wallingford, UK.

  15. 15

    Alam, A.S., Hagerman, L.M. and Imondi, A.R. 1980. Bioavailability of sulpiride tablet and capsule in dogs. Arch. Int. Pharmodyn. Ther. 247: 180–189.

  16. 16

    Doherty, A.M., Kaltenbronn, J.S., Hudspeth, J.P., Repine, J.T., Roark, W.H., Sircar, I., Tinney, F.J., Connolly, C.J., Hodges, J.C., Taylor, M.D., Batley, B.L., Ryan, M.J., Essenburg, A.D., Rapundalo, S.T., Weishaar, R.E., Humblet, C. and Lumney, E.A. 1991. New inhibitors of human renin that contain novel replacements at the P2 site. J. Med. Chem. 34: 1258–1271.

  17. 17

    Li, A.P. 1989. Protein toxicology applied to biotechnology products. In: Genetically Engineered Plants: Scientific Issues In Their Regulation For Animal Feed And Human Food Uses, Workshop at Boyce Thompson Institute for Plant Research and Cornell University, Ithaca, New York.

  18. 18

    Jones, D.D. and Maryanski, J.H. 1991. Safety considerations in the evaluation of transgenic plants for human food, p. 64–82. In: Risk Assessment In Genetically Engineering: Environmental Release Of Organisms. Levin, M. and Strauss, H. (Eds.). McGraw-Hill, New York.

  19. 19

    Pariza, M.W. and Foster, E.M. 1983. Determining the safety of enzymes used in food processing. J. Food Protection 46: 453–468.

  20. 20

    Pesticide testing guidelines. Subdivision M. Microbial and Biochemical Pest Control Agents. PB89-211676. National Technical Information Service, Springfield, VA.

  21. 21

    Fuchs, R.L., Heeren, R.A., Gustafson, M.E., Rogan, G.J., Bartnicki, D.E., Leimgruber, R.M., Finn, R.F., Hershman, A. and Berberich, S.A. 1993. Purification and characterization of microbially expressed neomycin phospho-transferase II (NPTII) protein and its equivalence to the plant expressed protein. Bio/Technology 11: This issue.

  22. 22

    Kessler, D.A., Taylor, M.R., Maryanski, J.H., Flamm, E.L. and Kahl, L.S. 1992. The safety of foods developed by biotechnology. Science 256: 1747–1749.

  23. 23

    Taylor, S.L., Nordlee, J.A. and Bush, R.K. 1992. Food allergies, p. 316–329. In: Food Safety Assessment, Ginley, J.W., Robinson, S.F. and Armstrong, D.J. (Eds.). ACS Symposium Series 484. ACS, Washington, DC.

  24. 24

    Taylor, S.L., Lemanske, R.F. Jr, Bush, R.K. and Busse, W.W. 1987. Food allergens: structure and immunologic properties. Ann. Allergy 59: 93–99.

  25. 25

    Sleisenger, M.H. and Fordtran, M.D. 1989. Gastrointestinal Disease, Volume 1. In: Pathophysiology Diagnosis Management, 4th Ed. W. B. Saunders Company, Philadelphia.

  26. 26

    Davenport, H.W. 1971. Physiology of the Digestive Tract, 3rd Ed. Year Book Medical Publishers, Inc., Chicago.

  27. 27

    Fuchs, R.L., Stone, T.B. and Lavrik, P.B. 1993. Risk assessment: a technical perspective. In: NABC Report 5, Agricultural Biotechnology: A Public Conversation About Risk, J. Fessenden MacDonald (Ed.). National Agricultural Biotechnology Council. Ithaca, NY.

  28. 28

    United States Enironmental Protection Agency (USEPA). 1984. Dietary residue evaluation system (ORES) (formerly TAS: Tolerance assessment system). Washington, D.C.

  29. 29

    Food and Drug Administration, Department of Health and Human Services. 1992. Statement of Policy: Foods Derived from New Plant Varieties. Fed. Reg. 57: 22984–23005.

  30. 30

    International Food Biotechnology Council. 1990. Biotechnologies and food: assuring the safety of foods produced by genetic modification. Reg. Toxicol. Pharmacol. 12: S1–S196.

  31. 31

    The United States Pharmacopeia, Vol. XXII, p. 1788–1789. United States Phar-macopeial Convention, Inc. Rockville, MD.

  32. 32

    Ryle, A.P. 1984. Pepsins, gastricsins and their zymogens, p. 223–238. In: Methods of Enzymatic Analysis, Vol. V. Bergmeyer, H.U. (Ed.). Verlag Chemie, Weinheim.

  33. 33

    Laemmli, U.K. 1970. Cleavage of structural proteins during assembly of the head of the bacteriophage T4. Nature 227: 680–685.

  34. 34

    Matsudaira, P. 1987. Sequence from picomole quantities of proteins electro-blotted onto polyvinylidene difluoride membranes. J. Biol. Chem. 262: 10035–10038.

  35. 35

    Goldman, P.R. and Northrop, D.B. 1976. Purification and spectrophotometric assay of neomycin phosphotransferase II. Biochem. Biophys. Res. Comm. 69: 230–236.

  36. 36

    Dunnett, C.W. 1955. A multiple comparison procedure for comparing several treatments with a control. J. Am. Stat. Assoc. 50: 10967–1121.

  37. 37

    Dixon, W.J. and Massey, F.J. Jr 1969. Introduction to Statistical Analysis, 3rd Ed. McGraw-Hill Co., NY.

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