Applications of Recombinant DNA

1. Applications in crop improvement

2. Applications in Medicine

3. Industrial Applications

Important Applications of recombinant DNA technology

1. Distant Hybridization

2. Development of Transgenic Plants

3. Development of Root Nodules in Cereal Crops

4. Development of c4 plants

Applications in crop improvement (4)

Distant Hybridization

Due to the development of genetic engineering, the transfer of genes between distantly related species are now possible. Desired Genes can be transferred to higher organisms from lower organisms.

Dianthus caryophyllus barbatus (Fairchild’s Mule)

A cross bred of carnation pink and sweet William

Dianthus caryohpyllus

Carnation Pink

Dianthus barbatus

Sweet William

Transgenic plants

Genetically altered plants which contain imported genes

Development of Transgenic Plants

Through recombinant DNA technology, genetically modified plants can resist diseases, insects, pests and herbicides. Some may tolerate drought and toxicity

Bt crops

Pest Resistant (cotton and maize), genetically modified so they are toxic to certain insects

Rhizobium

Nitrogen fixing bacteria found in the root-nodules of leguminous plants, it converts the free atmospheric nitrogen into nitrates in the root nodules.

Development of Root Nodules in Cereal Crops

Through genetic engineering, bacterial genes can be transferred to cereal crops (wheat, rice, maize, barley etc.) to make it capable too of fixing atmospheric nitrogen

Biological Nitrogen Fixation

BNF

BNF Rice

Example of development of root nodules in cereal crops

Photosynthetic efficiency

Improving this characteristic of crop plants can improve its yield

Protoplasm fusion

In order to increase the photosynthetic rate of crop plants, C3 plants must be converted into c4 plants

Recombinant DNA technology c4 plants

Have higher potential rate of biomass production than c3 plants

Sorghum, sugarcane,maize, some grasses

Examples of c4 plants

Applications in Medicine

1. Production of antibiotics

2. Production of hormone insulin

3. Production of vaccines

4. Diagnosis of diseases

5. Production of enzymes

6. Productions of Transgenic Animals

Antibiotics

Very common and effective cure for different viral, bacterial or protozoan diseases

Tetracycline, penicillin,streptomycin,niovobiocin, and bacitracin

Common examples of antibiotics produced by microorganisms

Production of Antibiotics

Improving the microbial stains through modification of genetic characteristics helps in increasing the production of antibiotics

Tetracycline

Broad-spectrum napthacene antibiotic produced semisynthetically

Chlortetracycyline

Antibiotic isolated from Streptomyces aureofaciens

Tetracycline

Used to treat a range of bacterial infections, including respiratory tract infections, urinary tract infections and skin infections

Hormone Insulin

Hormone used by diabetics usually extracted from the pancreas of pigs and cows, the structure of this insulin is slightly different from the human insulin which leads to allergic reactions in about 5% patients

Production of Hormone Insulin

Production of insulin is made by incorporating human gene into the bacterial DNA. This genetically modified bacteria are used for the production of insulin

Geneticist Walter Gilbert and Molecular Biologist Lydia Villa-Komaroff

Working independently from the commercial biotech industry, along with their team at Harvard successfully located the human insulin gene

Vaccine

What can transfer of antigen coding genes to disease causing bacteria produce?

Antibodies

Protects the hosts against the infection by the same bacteria or virus

Vaccines for polio, malaria, cholera, hepatitis, rabies and smallpox

Some examples of vaccines developed through genetic engineering

Inactive Polio Vaccine (IPV)

Example of vaccine for polio

Diagnosis of Diseases

Physicians were able to diagnose some diseases through recombinant DNA. Some investigations are now used in detecting infectious agents like food poisoning of Salmonella, Pus forming Staphylococcus, hepatitis virus, HIV and others

Nucleic Acid Test and Antigen/Antibody Test

Types of tests conducted to detect HIV (Human Immunodeficiency Virus)

Enzyme Urokinase

Used to dissolve blood clots

Production of chymosin

Important in cheese production, it was naturally extracted from calve’s stomach but due to modernization, it can be produced from microorganisms

Production of Transgenic Animals

In order to produce transgenic animals, preferred genes is introduced into an animal, this method helps in increasing the variety of selective breeding in animals, it also ensures that better farm animals will be produced for marketable benefits

Pigs, sheeps,rats,cattles

Some examples of transgenic animals produced

Dolly the Sheep

First transgenic animal

Biofuels

Derived from biomass, renewable and cost effective

Genetic engineering

Plays an important role in a beneficial and large scale production of biofuels, helps in improving the organisms for obtaining higher product yields and improve tolerance

Recombinant DNA technique

Help in the production of chemical compounds of commercial importance, improvement of existing fermentation processes and production of proteins from wastes, can be achieved by developing more efficient strains of microorganisms

Specially developed microorganisms

Used to clean up pollutants