[priyasaravanan_1406]

The basic principle of genetic engineering is gene transfer, achieved by various methods to produce recombinant proteins, genetically modified microorganisms, transgenic plants and transgenic animals for commercial application. Genetic engineering, thus ultimately influences the growth of biotech industry. The two significant feature of genetic engineering is production of beneficial proteins and enzymes in surplus quantities and creation of transgenic plants, transgenic animals and genetically modified microorganisms with new characters beneficial for themselves using recombinant DNA technology. The discovery of a new protein either with a therapeutic property or application in food industry by a researcher or scientist would not have reached humans, for the use by humans without the application of genetic engineering in mass producing such proteins.

Recombinant proteins production and uses: The industrial production of proteins is done by transferring the desired gene responsible for the particular protein to be manufactured from the source organism to the preferred host organism through recombinant DNA technology. The host organism can be a bacteria or a eukaryote. The most preferred bacterial host is Escherichia coli for industrial production of proteins. The well established gene structure, faster growth rate, easy to cultivate and handle are the salient features of the E. coli bacterium fascinated the bio technologists to use this in recombinant protein production. Besides all these commendable characters of E. coli, the final output product is found to be unstable and difficult to purify. As a result research encouraged the use of eukaryotic host like yeast, cells of insects and cells of mammals in protein production. The proteins produced in this way find its way into pharmaceutical industry and food industry.

The recombinant proteins produced in the industry using the techniques of genetic engineering acts as drugs for various human diseases. To name a few, insulin produced for diabetes, alpha 1- antitrypsin in treating emphysema, calcitonin to treat rickets, interferon to treat viral infections and cancer, Factor VIII for hemophilia, production of growth hormone to act against growth retardation and chorionic gonadotrophin in the treatment of infertility. Some of the industrial manufactured enzymes occupy a vital position in the food industry. For example, the recombinant enzymes like rennin and lipase are used in cheese making, the role of alpha- amylase in beer industry, the antioxidant property of the industrially produced enzyme catalase and the use of protease in detergents.

Uses of Transgenic plants: In order to improve the quality and quantity of plants, traditional method of plant breeding is replaced by the creation of transgenic plants. The transgenic plants are plants carrying foreign genes introduced deliberately into them to develop a new character useful for the plant. The infection of plants by microorganism mostly viruses, poor production and decline in quality of plants due to attack by insects and the plants inability to withstand the pesticide or the weedicide used in the agriculture process welcomed the genetic engineering technology to develop transgenic plants with new characters like resistance to infections, defensive against the attacking insects and resistance to pesticides or weedicide.

The transfer of gene responsible for the protein protoxin from Bacillus thuringiensis to plants to develop resistance against the attacking insects is a remarkable example. Also the digestive action of the insects on the plants is restricted or inhibited by transfer of gene responsible for a particular protein with the property to arrest protease activity. The pesticides and weedicides used to destroy the pests and weeds is also a threat to the cultivated plants. The effects of such chemicals are alleviated by developing a new character called resistance to chemicals in plants. Development of resistance in plants against the weedicide glyphosate states the role of genetic engineering in plant breeding.

Uses Transgenic animals: Transgenic animals are animals carrying foreign genes deliberately introduced into them and exhibiting the characteristics of the introduced gene. Animals are suitable for various research activities trying to help mankind. In that way transgenic animals are created to study human diseases to derive appropriate treatment methods and to develop and identify the drug useful to treat the disease. The presence of human proteins in milk of animals is made possible by genetic engineering. Gene transfer is done in animals to increase the milk production and to increase the growth.

Like a coin has two sides, the other face of genetic engineering like creation of genetically modified organisms to be used as biological weapons is not welcoming.