General Knowledge Notes For All Competitive Exams - Biology-Part -01

General Knowledge Notes For All Competitive Exams - Biology-Part -01(Download as PDF)

Applications Of Genetic Engineering

At home we prepare food items such as yoghurt (curd), cake, bread, idli and dosa by the action of microorganisms, such as the bacteria and fungi. Brewers use yeast (fungus) to make beer. Antibiotics such as penicillin are obtained from certain fungi. Nowadays, biological processes such as fermentation by microorganisms is being used in industry on a commercial scale for making food, drinks, drugs (medicines) and industrial chemicals. Modern techniques in biotechnology are programming microorganisms for this task.

Protein manufacture :

We are well familiar that bacteria and yeasts have been used for centuries to produce cheese, and alcohol, and more recently antibiotics. Currently, plasmids in bioengineered bacteria carry some human genes and these genes are expressed to give large quantities of human proteins which are clinically useful. The development of recombinant DNA technology and gene cloning has generated

a new industry for manufacturing proteins. Earlier valuable proteins could be obtained from eukaryotes in small amounts and at heavy expense, but now these can be produced in large quantities. 

For example: Until sometime back, growth hormone was available only in tiny amounts and was extremely expensive as it had to be extracted from endocrine glands of certain animals. Today, it can be made available in large quantities through recombinant DNA technology. 

In 1982 production of human insulin became the first commercial success of recombinant DNA technology. There are several proteins of therapeutic (medical) value which are available now through recombinant DNA technology. These are cloned human gene products approved for use or being developed. 

Here lets know the names of proteins and their uses:

•  Insulin - Diabetes mellitus
•  Growth hormone - Pituitary dwarfism
•  Erythropoietin - Anaemia
•  Interferons - viral infections
•  Interleukin 2 - Cancer
•  Clotting factor VIII - Haemophilia A
•  Clotting factor IX - Haemophilia B
•  Monoclonal antibodies - Infectious diseases
•  Tissue Plasminogen factor - Heart attack

Enzymes:

 Enzymes have also been produced from cloned genes. Lets have the names of such enzymes and their uses: 

•  Proteases-  manufacture of detergents, meat tenderisers.
•  Amylases - manufacture of beer, bread and textiles
• Glucoisomerases - to make corn syrup, which is sweeter than sucrose and used to flavour soft drinks

 Antibiotics:

Since the discovery of Penicillin in 1920s, more than 6000 antibiotics have been isolated from various microorganisms and have resulted in an enormous improvement in human health. Research is in progress to genetically engineer biosynthetic pathways for the synthesis of antibiotics. Novel antibiotics have also been obtained through genetic manipulation.Some of the common antibiotics and their source organisms are as follows:

• Tetracyclin -  Streptomyces sp
• Chlorotetracycline - Streptomyces auriefaciens
• Chloramphenicol -  S. venezuelae
• Cycloheximide - S. griseus
• Streptomycin - S. griseus
• Cephalosporin - Cephalosporium acremonium
• Penicillin - Penicillium chrysogenum

 Vaccines:

Bioengineered vaccines have been developed for rabies and hepatitis B. A gene for the antigen protein is inserted into a plasmid and the bacteria containing recombinant DNA then generate large quantities of the protein. The protein is added to the vaccine. Antibodies immediately form against the antigen when vaccinated.