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November 20, 2024What do you understand about the term biotechnology? Seems like this word has become a buzzword, nowadays and is always in news for different things such as Dolly the cloned sheep, genetically modified organisms, gene therapy etc. Biotechnology is the science in which biology and technology are used to make products such as processed food, modified crops, medicines, and many more for the betterment of humans. Biotechnology and its applications have a significant role in developing agriculture, the food industry, healthcare, and genetically modified organisms. Let us learn more about biotechnology and its applications.
Biotechnology is the technology that utilises biological systems that can only be achieved through the integration of biological, physical, and engineering sciences. Biotechnology has tremendous applications in different fields such as therapeutics, diagnostics, processed food, waste management, energy production, genetically modified crops, etc.
Biotechnology deals with technology and involves various applications in different fields like therapeutics, diagnostics, genetically modified organisms, processed food, bioremediation, waste treatment, and energy production. Human beings have been using biotechnology to improve the quality of human life, especially in food production and health.
Fig: Major Applications of Biotechnology
Agricultural biotechnology is also called green biotechnology. The important methods that are very useful for increasing food production are:
1. Agrochemical based agriculture
2. Organic agriculture or organic farming
3. Genetically Engineered Crop-based Agriculture
1. Agrochemical based agriculture– The green revolution succeeded in enhancing the food supply due to
a) Use of improved varieties of crops.
b) Use of agrochemicals (fertilisers and pesticides).
c) Better management practices.
But it was not enough to feed the growing human population.
2. Organic agriculture or organic farming- Organic farming is a type of farming in which organic manures, biofertilizers, biopesticides, etc., are used to increase the productivity of the plants. In this method, chemical fertilisers and pesticides are not used.
3. Genetically Engineered Crop- based Agriculture- Organic farming cannot increase crop production significantly. Therefore, the best solution to overcome all these issues is to use genetically modified crops.
Genetically modified organisms (GMOs) are organisms like plants, bacteria, fungi, and animals. The genetic material (DNA) has been altered or artificially manipulated so that it does not occur naturally by mating or natural recombination. These are also known as transgenic organisms as they contain and express one or more foreign genes called transgenes.
a) Transgenic Plants or GM crops– It is a type of crop whose DNA is altered through genetic engineering techniques. These plants are helpful in many ways like:
i) The produced crops are more tolerant of abiotic stresses like cold, drought, salt, and heat.
ii) The nutritional value of the crops is enhanced.
iii) The production of a new phenotype takes place.
iv) This helped to reduce post-harvest losses.
v) Increases nutritional value of food.
Examples of GM crops are:
1. Bt cotton is pest-resistant, herbicide-tolerant, and a high-yielding plant. Bt Crops are transgenic plants that contain a foreign gene obtained from Bacillus thuringiensis bacteria in the plant cell, protecting the plants against pests. The Bt toxin gene was cloned from bacteria and produced in plants to offer insect resistance.
Fig: Bt Cotton
2. Golden rice is Vitamin-A-rich rice.
Fig: Golden Rice
3. Potatoes with higher protein content.
4. Bt corn and Bt brinjal are insect-resistant transgenic plants.
5. Herbicide resistance traits are found in Maize and soybeans.
b) Pest resistant plants– Wide variety of plants and animals are infected by several nematodes.
1. A nematode Meloidogyne incognita infects the roots of tobacco plants which decreases the production of tobacco. RNA interference (RNAi) method is used to prevent the attack of nematodes. This is a process of cellular defence that takes place in all eukaryotic organisms. This involves the silencing of a specific mRNA due to the use of a complementary RNA that degrades the mRNA of a nematode responsible for infection in the roots of the tobacco plant.
2. The gene for an enzyme that synthesises a chemical toxic to weevils has been transferred from Bacillus bacteria to the Rhizobium bacteria that live in the root nodules of legume plants. These root nodules are resistant to attack by the weevils.
c) Herbicide-resistant crops– The gene for resistance to the herbicide basta has been transferred from Streptomyces bacteria to tomato, potato, corn, and wheat plants, making them resistant to basta. These herbicides can be sprayed safely in the fields, which will kill all weeds but not the crops.
(i) The recombinant DNA technological processes have made a massive impact on healthcare by enabling mass production of genetically engineered medicines such as insulin. Also, by creating methods like gene therapy, recombinant DNA technology, Polymerase Chain Reaction (PCR), and Enzyme-Linked Immuno-sorbent Assay (ELISA).
(ii) Around \(30\) recombinant therapeutics have been approved for human use across the globe.
(iii) Genetically Engineered Insulin:
(a) The insulin used for the treatment of diabetes was earlier extracted from the pancreas of slaughtered cattle and pigs. This causes allergies in some patients.
(b) The structure of insulin consists of two short polypeptide chains: chain \(A\) and chain \(B.\) They are linked together by disulphide bridges.
(c) In humans, insulin is synthesised as a prohormone, which consists of an extra stretch called the \(C-\)peptide. This peptide is absent in the mature insulin that is removed during its maturation into insulin.
(d) Two DNA sequences were prepared to correspond to \(A\) and \(B\) chains of human insulin and were introduced into plasmids of E. coli for the production of insulin chains.
(e) The Polypeptide Chains \(A\) and \(B\) were produced separately, which were extracted and combined by creating disulphide bonds to produce human insulin.
Fig: Genetically Engineered Insulin
(iv) Gene Therapy:
a. Gene therapy collects methodologies used to correct a faulty gene by a healthy and functional gene.
b. Correction of a genetic defect involves introducing a normal gene into the cells or tissues to take over the function of and compensate for the non-functional gene.
c. This therapy is mainly tried for sickle-cell anaemia and Severe Combined Immunodeficiency Disease (SCID).
d. The first clinical gene therapy was done on a four-year-old girl in the year \(1990\) with adenosine deaminase (ADA) deficiency which is caused due to the deletion of the gene coding for adenosine deaminase.
e. The ADA enzyme is essential for the immune system to function.
f. WBCs from the patient’s blood is grown in an in vitro culture, and a functional ADA cDNA (complementary DNA) using a retroviral vector is then incorporated into these WBCs. Later with the use of a retroviral vector which is returned to the patient.
g. ADA deficiency can be cured with bone marrow transplantation or enzyme replacement therapy in some children in which functional ADA is introduced into the patient by injection.
(v) Molecular diagnosis:
a. Recombinant DNA technology (RDT), Polymerase Chain Reaction (PCR) and Enzyme-Linked Immuno-sorbent Assay (ELISA) are some of the principal molecular diagnoses that aid the early diagnosis to recognise and understand the pathophysiology of the disease.
b. PCR is used to detect HIV in suspected AIDS patients and to detect mutations in genes in suspected cancer patients.
c. Minute amounts of bacteria or viruses can be detected by amplifying their nucleic acids achieved with PCR.
d. A single-stranded DNA or RNA tagged with a radioactive molecule(probe) is made to hybridise its complementary DNA in a clone of cells. This is followed by detection with autoradiography. The clone possessing the mutated gene will not appear on the photographic film as the probe will not complement the mutated gene.
e. ELISA is carried out based on the principle of antigen-antibody interaction. Infection caused by a pathogen can be recognised by the presence of antigens or by detecting the antibodies synthesised against the pathogen.
(vi) Antibiotics: Alexander Flemming \((1928)\) discovered the antibiotic Penicillin from the fungus Penicillium notatum to treat Pneumonia and other diseases.
(vii) Vaccines: Recombinant DNA technology is used in the production of many new generation vaccines.
1. Transgenic animals are those that have had their DNA manipulated to possess and express a foreign gene.
2. For example, transgenic rats, rabbits, pigs, sheep, etc.
3. Transgenic animals are created for the following purposes:
(a) To study the regulation of genes and how they affect normal functions and development of the body.
(b) For example, the study of complex factors involved in growth, such as insulin-like growth factors.
(c) To study genes that contribute to the development of disease.
(d) To produce biological products such as human protein (\(?-1-\)antitrypsin) used to treat emphysema, proteins to cure phenylketonuria and cystic fibrosis.
(e) They are also used to produce human alpha-lactalbumin enriched milk. For example, the first transgenic cow, Rosie, produced human protein-enriched milk of around \(2.4\,{\rm{grams/litre}}\).
(f) For the safety testing of vaccines before they are used on humans. For example, transgenic mice are widely being used to test the safety of the polio vaccine.
(g) For testing the toxicity of drugs.
Fig: A- Methodology of Transgenic Animal Production
Fig: B- Methodology of Transgenic Animal Production
i) Production of industrial enzymes- Many enzymes are produced at the industrial level, such as amylase used in the brewing, baking, and textile industries. Protease enzyme is used in meat, leather, and detergent industries.
ii) Improvement in fermentation products:
a) Bread is produced by yeast fermentation of sugar produced from flour.
b) Beer is produced from brewing barley grain.
c) Wine is produced by the fermentation of different varieties of grapes.
iii) Formation of dairy products from lactic acid fermentation: Different dairy products like cheese, yoghurt, butter are formed from the fermentation of milk.
iv) Production of Single-cell protein- These are formed by the large-scale growth of microorganisms like bacteria, algae, yeast, and other fungi. These can be consumed as food by humans or other animals due to their high protein content. Some examples of SCP are “Protein” produced from a bacterium Methylophilus methylotrophus, “Mycoprotein” produced from fungus Fusarium graminearum.
v) Metal extraction in mine- Microorganisms are essential to convert insoluble metals into soluble metals. This process is called leaching. Example: Copper and Uranium can be extracted by Thiobacillus.
Biotechnological products help in the protection of the environment. These are eco-friendly, unique, efficient, and less toxic.
i) Biofuel– Biofuels are mainly derived from biomass. Methanobacterium produces biogas methane by the fermentation of faecal material of cattle or water hyacinth plants. Ethanol is produced by the fermentation of molasses obtained from sugarcane by the yeast.
ii) Biosensors– These are electronic monitoring devices in which any organism, microorganism, enzyme system, or other biological structure is used as an assay or indicator to detect or measure a chemical compound. Example: The enzyme glucose oxidase is used as a biosensor to detect the amount of glucose in the blood.
Biotechnology refers to the combination of biology and technology, which helps to produce modified products for the betterment of humans. Biotechnology plays a vital role in modified crops, medicines, waste management, processed food, and producing genetically modified living organisms. Biotechnology and its application help improve agriculture, industries, the protection of the environment, and the development of transgenic animals.
Q.1. What is biotechnology?
Ans: Biotechnology is the application of the biological system in technology that can only be achieved through the integration of biological, physical, and engineering sciences.
Q.2. Write two applications of biotechnology in agriculture.
Ans: The two applications of biotechnology in agriculture are:
i) Production of transgenic plants or GM crops.
ii) Formation of pest-resistant plants.
Q.3. Which transgenic crop was first approved for commercial cultivation in India?
Ans: Bt cotton was the first approved transgenic crop for commercial cultivation in India.
Q.4. What is the use of PCR?
Ans: It is the technique for synthesising multiple copies of the desired gene or DNA fragment in vitro.
Q.5. What is gene therapy?
Ans: Gene therapy collects methodologies used to correct a faulty gene by a healthy and functional gene.