transgenic bacteria

transgenic bacteria

1. Transgenic bacteria Manjunath, G.A

2. What are GMO’s? Genetically Modified Organisms are organisms that have been genetically altered to carry and/or produce a certain necessary gene. This is done by inserting the required gene into the organism’s DNA. There are three types of GMO’s: animals, plants and bacteria We focused on bacteria.

3. How are GMO’s made? A specific gene is chosen and then extracted from DNA using a restriction enzyme. This gene is then inserted into a bacterium. Since these are single celled organisms the gene only has to be inserted once and because bacteria multiply quickly, they are an ideal candidate for mass production of a specific gene.

4. Why is it relevant to society? GM bacteria are relevant to society, because they are a fast and easy way to make a lot of a selected gene. They can be used to cure and prevent sicknesses, to create medicines, to improve the environment in numerous ways and to help in many other ways.

5. Benefits of GM Bacteria In the Environment- Possible control of weeds and use of GMOs that reduce the use of toxic chemicals, GMOs to decontaminate toxic waste sites, GMOs in environmental friendly power In Farms- Improved nutrition for people, increased environmental protection through the reduced use of pesticides, and increased quality and quantity of yields, as well as increased farm profitability through reduced costs and new product opportunities

6. Degradation of oil spill : gene that synthesize lipase (fat digesting enzyme) from animal is inserted into bacteria Used to clean oil spill that cause water pollution. Nitrogen fixation : producing bacteria that can fix nitrogen to increase crops production. Anti-freezing bacteria (transgenic) is sprayed to the plants to prevent the ice formation. Eg : tomatoes, strawberries

7. Transgenic plant transgenic plant : plants that has useful foreign genes from another species. Has desirable improved characteristics - e.g : Pests and herbicides resistance, delay ripening, improve flavour

8. 1985 1992 1988 1994 1998 1996 1999 2000 1st transgenic plants produced Particle bombardment developed GM crops considered substantially equivalent to hybrid varieties Flavr-Savr tomato is released Herbicide- and insect-resistant crops approved for cultivation 4.3 million acres of GM crops planted GM food is dangerous (UK TV) Monarch butterfly paper causes uproar GM corn is excluded from its baby food Greenpeace starts anti-GM campaign 75 million acres of GM crops planted Golden rice with ß-carotene developed McDonald’s rejects GM potatoes

9. TRANSGENIC PLANTS NUTRITIONAL QUALITY BIOTIC STRESS TOLERANCE ABIOTIC STRESS TOLERANCE PHARMACEUTICALS & EDIBLE VACCINE HYBRID DEVELOPMENT FOR HIGHER YIELD ENHANCED SHELF LIFE INDUSTRIAL PRODUCTS

10. Important Traits for Crop Improvement High crop yield High nutritional quality Abiotic stress tolerance Pest resistance Adaptation to inter-cropping Nitrogen Fixation Insensitivity to photo-period Elimination of toxic compounds

11. Insect Resistance Delayed Fruit Ripening Nutritional Enhancing Herbicide Resistance Virus Resistance The big five successful traits

12. Resistance to herbicide Gene for herbicide resistance can be inserted into a crop plant’s chromosomal DNA Herbicides will have no effect on the transgenic crop plants and only destroy the weeds

13. Glyphosate Resistance Glyphosate = “Roundup”, “Tumbleweed” = Systemic herbicide Marketed under the name Roundup, glyphosate inhibits the enzyme EPSPS (S-enol p yruvl s hikimate-3 p hosphate – involved in chloroplast amino acid synthesis) , makes aromatic amino acids. The gene encoding EPSPS has been transferred from glyphosate-resistant E . coli into plants, allowing plants to be resistant. Glufosinate Resistance Glufosinate (the active ingredient being phosphinothricin ) mimics the structure of the amino acid glutamine, which blocks the enzyme glutamate synthase . Plants receive a gene from the bacterium Streptomyces (bar gene) that produce a protein that inactivates the herbicide . Herbicide Resistance

14. Bromoxynil Resistance A gene encoding the enzyme bromoxynil nitrilase (BXN) is transferred from Klebsiella pneumoniae bacteria to plants. Nitrilase inactivates the Bromoxynil before it kills the plant. Sulfonylurea . Kills plants by blocking an enzyme needed for synthesis of the amino acids valine , leucine , and isoleucine . Resistance generated by mutating a gene in tobacco plants ( acetolactate synthase ), and transferring the mutated gene into crop plants. Herbicide Resistance

15. Roundup Ready™ Soybeans A problem in agriculture is the reduced growth of crops imposed by the presence of unwanted weeds. Herbicides such as Roundup and Liberty Link are able to kill a wide range of weeds and have the advantage of breaking down easily. Development of herbicide resistant crops allows the elimination of surrounding weeds without harm to the crops .

16. Insect resistance a) Toxic crystal protein from Bacillus thuringensis Toxic crystals found during sporulation Alkaline protein degrades gut wall of lepidopteran larvae Corn borer catepillars Cotton bollworm catepillars Tobacco hornworm catepillars Gypsy moth larvae The Bt toxin isolated from Bacillus thuringiensis has been used in plants. The gene has been placed in corn, cotton, and potato, and has been marketed.

17. Insect Resistance Corn hybrid with a Bt gene Corn hybrid susceptible to European corn borer Various insect resistant crops have been produced. Most of these make use of the Cry gene in the bacteria Bacillus thuringiensis (Bt) ; this gene directs the production of a protein that causes paralysis and death to many insects .

18. δ -endotoxin gene ( Cry gene) of Bacillus thuriengenesis GENE FOR Bt TOXIN WAS TRANSFERRED TO OBTAIN BT TRANSGENIC PLANTS PLANT SYNTHESIZES INACTIVE PROTOXIN PROTEINASE DIGESTION IN INSECT GUT MAKES THE ACTIVE TOXIN Toxin binds a receptor on the gut epithelial cells, forms a channel on the membrane. This causes electrolyte leakage and insect death INSECT FEEDS ON TRANSGENIC PLANT

19. Allow for crops, such as tomatoes, to have a higher shelf life. Tomatoes generally ripen and become soft during shipment to a store. Tomatoes are usually picked and sprayed with the plant hormone ethylene to induce ripening, although this does not improve taste Tomatoes have been engineered to produce less ethylene so they can develop more taste before ripening, and shipment to markets Delayed Fruit Ripening

20. What happened to the Flavr Savr tomato? Produced by blocking the polygalacturonase (PG) gene, which is involved in spoilage. PG is an enzyme that breaks down pectin, which is found in plant cell walls. Plants were transformed with the anti-sense PG gene, which is mRNA that base pair with mRNA that the plant produces, essentially blocking the gene from translation. First genetically modified organism to be approved by the FDA, in 1994. Tomatoes were delicate, did not grow well in Florida, and cost much more than regular tomatoes. Calgene was sold to Monsanto after Monsanto filed a patent-infringement lawsuit against Calgene , and the Flavr Savr tomato left the market. Delayed Fruit Ripening

21. First biotech plant product – Flav’r Sav’r tomato “ Rot-Resistant Tomato”

22. Colorful Cauliflowers

23. Purple tomatoes

24. The disadvantages of genetically modified crops are: Proteins produced by GM organisms may cause allergies and other diseases Persistent release of insecticidal proteins by GMO’s may disrupt the biological activity of the soil. Horizontal transfer of antibiotic resistant genes from transgenic crops to bacteria The genetically modified crops may eliminate the indigenous varieties through competition for minerals and nutrients Environmental risk of crop developed using GMO’s Genetically modified crops may turn benign organisms into destructive pests.