- 1 Explore Biotechnology and Its Principles – Types and Applications of Biotechnology
- 1.1 History of Biotechnology
- 1.2 Biotechnology and Its Various Disciplines
- 1.3 A. Genetic Engineering
- 1.4 B. Bioprocess Engineering
- 1.5 Ethics of Biotechnology
- 1.6 Areas of Biotechnology
- 1.7 A. Based on the time of origin
- 1.8 B. Based on wideness (dimension)
- 1.9 C. Based on Application and Nature
- 1.10 D. Based on Type of Organism
- 1.11 Biotechnology and Its Interdisciplinary Approach
- 1.12 Scope of Biotechnology
- 1.13 Examples of Some Modern Biotechnological Innovations
- 1.14 A. Gene Fusion
- 1.15 B. Protoplast Fusion:
- 1.16 C. Gene Amplification
- 1.17 D. Creation of Hybridoma
- 1.18 E. Recombinant DNA Technology and Genetic Engineering
Microbiology is one of the Biology Topics that involves the study of microorganisms, including bacteria, viruses, and fungi.
Explore Biotechnology and Its Principles – Types and Applications of Biotechnology
According to British Biotechnologists: The application of a living organism or any technique used by a living organism for manufacturing and assisting industry is called biotechnology.
According to Japanese Biotechnologists: The technology that uses the procedures of living beings for the production of useful materials is called biotechnology.
U.S. National Science Foundation advocates that Biotechnology is the controlled use of microbes or other cellular entities for human welfare.
The European Federation of Biotechnology says that Biotechnology is the combination of Biochemistry, Microbiology, and Technology application systems that by using microbes, cultured cells, or cellular ingredients bring forth comforts for man and society.
Though there are different definitions developed for biotechnology by amalgamating all definitions, Biotechnology may be defined as the use and industrial application of knowledge and techniques of biochemistry, microbiology, genetics, and chemical engineering, to draw benefit, at the technological level, from the properties and capacities of living organisms and their products. Biotechnology offers the possibility of producing, from living organisms and other renewable sources, substances and compounds essential to life and the greater well-being of human beings.
The techniques of using living organisms or their products for human welfare and comfort are considered as biotechnology. In biotechnology, living organisms are used in industrial processes – particularly in agriculture, food processing, and medicine. Biotechnology has been the culture of man from the very remote past since humans began manipulating living organisms and their products to improve their food supply, housing, and health. For example, people have been making wine, beer, cheese, and bread for centuries using microorganisms such as yeast.
However, the practices of the old days in this regard are called conventional/traditional biotechnology which does not require special scientific knowledge or training to achieve some desired result. Several such conventional biotechnologies include the production of curd and cheese from milk, the production of alcohol from decomposed food, the production of vinegar, the production of plants through grafting and the production of oil from oil seeds and husk, the production of idli, dhosa, vada, dhokla, shrikhand, etc.,. But in the present time, after the discovery of the methods of recombinant DNA technology and genetic engineering, biotechnology has achieved a new dimension and has appeared now as a separate and distinct discipline of science. With the use of biotechnology as per plan people can earn substantial amounts of money.
The subject is getting much importance in all the developed countries for its potential boosting effects on the national economy. With modern biotechnology, improved food materials, new medicines for treating diseases, and effective vaccines are being produced. Production of high-yielding varieties of plants and animals through hybridization is another simple biotechnology approach. Using biotechnology genetically modified plants have been produced with useful foreign genes inserted in their genomes to protect them, from insects, thus increasing the crop yield while decreasing the amount of insecticides used. Innovation of techniques of therapy involving genetic engineering for ameliorating inherited and fatal disease conditions in humans has been another remarkable achievement of modern biotechnology.
The structure and composition of genes for desired characters in many cases are now known to us and therefore, these genes and their products could be produced artificially. Useful genes from various economically important plants and animals have been cloned to produce a library of genes to store their information safely for later use. By using these genes desired proteins may also be produced for use in various industries. Gene technology is also being used for the identification of living organisms. Considering all these aspects, biotechnology may be considered as a unique weapon for the betterment of society and the advancement of civilization.
With the help of conventional biotechnology, we may produce many components for human use. A list of such items, their source, and uses may be indicated in the following table.
Several food products are obtained through conventional biotechnology:
|Food Materials||Source||Use||Country/Region where it is Produced|
|Bhatura||Flour||Taken as food with gram.||North India.|
|Chhurpi||Milk||Used as high energy contributing food.||Colder region of the country (The Himalayas).|
|Dosa||Rice||The staple food is taken as popular food.||South India.|
|Dhokla||Gram||Spongy tasty food.||Western Region.|
|Gundrum||Vegetables||Soup with a sour taste.||Himalayan Region.|
|Mesu||Bamboo||Sour Pickle||Himalayan Region|
|Curd||Milk||Lassi Preparation.||All regions of the country.|
|Cottage Cheese||Milk||Curry Preparation||North India|
|Tari||Palm juice||Narcotic with a sweet taste.||Eastern India.|
However, the fields of genetics, molecular biology, microbiology, and biochemistry are merging with their respective discoveries into the expanding applied field of modern biotechnology. This has significantly contributed to the society and a list of such contributions has been presented below.
Several food products are obtained through conventional biotechnology:
|Pharmaceuticals||(i) Human insulin.||(i) Treatment of diabetes.|
|(ii) Human Growth hormone.||(ii) Treatment of dwarfism.|
|(iii) Blood coagulating factor VIII.||(iii) Treatment of haemophilia.|
|(iv) Taxol.||(iv) Treatment of breast cancer.|
|(v) Hepatitis A and hepatitis B vaccine.||(v) Jaundice.|
|(vi) Haemoglobin (Human).||(vi) Emergency blood transfusion.|
|Industry||Oil-consuming bacteria, production of glyphosate-resistant plants.||Removal of oil pollution. Protection of cultivated plants from weeds.|
|Agriculture||Hybrid plants, enzymes, vitamins, and amino acids.||High-yielding, treatment of disease due to deficiency.|
|Research||DNA and RNA probes, gene library.||Detection of genetic defects in newborns, identification of organisms, determination of functions, and structure of genes.|
History of Biotechnology
Biotechnology has an old history. In a true sense, it cannot be designated as modern science or technology. From the remote past people would depend on the methods of biotechnology to maintain their livelihood. It was extended from kitchen to medicine. The use of salt in preserving the food material is an age-old practice. This may be considered as the simplest form of biotechnology. Besides this preparation of in-house pickles, preparation of aromatic tasty food with the application of chemicals, tenderizing meat with the application of papaya juice, and preparation of jam and jelly are some of the different age-old practices of man.
In agriculture, the practice of hybridization by cultivators for obtaining high-yielding varieties as well as the use of the grafting technique in plants to produce quality plants are the two age-old techniques of biotechnology. The use of herbal products in the treatment of diseases is also an ancient practice. Even a common man knows the beneficial roles of medicinal plants and herbal products. Depending on these petty biotechnological procedures, recombinant DNA technology has led to the flourishing of biotechnology in the present time. Biotechnology affects all of our lives and has altered everything we encounter in life. Generation of a ‘test-tube’ baby through in vitro fertilization, synthesizing a gene and using it to produce useful protein (like human insulin for diabetic people) in bulk amounts, developing DNA vaccines against a virus, or correcting a defective gene through gene therapy, all are parts of biotechnology.
Historically biotechnology appears to be about 8000 years old and it originated at about 6000 B.C. At that time people knew about the procedure of preparing beer. During 4000 B.C. people knew the procedure of preparing spongy breads by using yeasts. However, biotechnology got its recognition only during the 1920s and the successive evolution of biotechnology may be shown in the following table.
Sequential Advancements of Biotechnology:
|6000 BC||Production of wine and beer by using yeast.|
|4000 BC||Production of spongy bread by using yeast.|
|1670-1680||Harvesting copper from mines by using microbes.|
|1897||The discovery that enzymes from yeast can produce alcohol from sugar.|
|1912-1914||Production of acetone, butanol, and glycerol from microbes.|
|1928||Discovery of penicillin by Alexander Fleming.|
|1962||Harvesting uranium from mines using microbes.|
|1975||Production of monoclonal antibody with the help of hybridoma.|
|1982||Use of insulin produced industrially for the treatment of diabetes.|
|Between the mid-80s to its last part||(i) Treatment of dwarfism with the use of growth hormone obtained through recombinant DNA technology.|
|(ii) Use of engineered protein in the treatment of heart attack and stroke.|
|(iii) Production of more milk from cattle by using growth hormone.|
|(iv) Industrial production of various chemicals by using microbes.|
|(v) Use of interferon in cancer treatment.|
|During the 90s and after||(i) Production and use of biofertilizer.|
|(ii) Production of vaccines for several diseases.|
|(iii) Use of monoclonal antibodies in cancer treatment.|
|(iv) Invention of OPV.|
|(v) Production of H2 in large scale by using microbes.|
|(vi) Production of pest-resistant plants (BT crop).|
|(vii) Invention of improved techniques for genetic engineering.|
Discoveries related to the development of biotechnology:
|7000 BC||Chinese people produced beer through fermentation.|
|6000 BC||Production of curd and paneer with the help of bacteria.|
|4000 BC||Egyptians produced puffed bread by using yeast.|
|500 BC||Yeast-infected soybean curd was first used as an antibiotic.|
|250 BC||Greeks started crop recycling methods to increase the fertility of soil.|
|100||Chrysanthemum was used as an insecticide by Chinese people.|
|Before 20th Century|
|1798||The smallpox vaccine was discovered by Edward Jenner.|
|1862||The bacterial fermentation process was discovered by Louis Pasteur.|
|1864||A centrifuge-type machine was discovered by Antonin Prandtl for the separation of cream from milk.|
|1881||Cholera and Anthrax vaccines were discovered by Louis Pasteur.|
|1885||The vaccine for hydrophobia was discovered by Louis Pasteur and Emile Roux.|
|1919||An agricultural engineer in Hungary first coined the term ‘biotechnology’.|
|1953||DNA structure was first revealed by James Watson and Francis Crick.|
|1973-1974||The recombinant DNA experiment was successfully done by Stanley Norman Cohen and Herbert Boyer.|
|1975||Production of monoclonal antibody by Kohler and Seizer.|
|1978||Site-specific mutation of DNA was first exhibited by Hutchinson and Marshall.|
|1980||Gene cloning patents have been given in America.|
|1982||Human insulin was produced from bacteria by the help of biotechnology. It was the first medicine derived from biotechnology.|
|1983||Discovery of Polymerase Chain Reaction (PCR).|
|1990||First recognized gene therapy.|
|1994||American Government first recognized ‘Flavrsavr’, a GM tomato.|
|1997||Animal cloning procedure was discovered by British Scientist Ian Wilmut and his co-workers. They incorporated the cell nucleus from an adult cell into an unfertilized oocyte that has had its cell nucleus removed.|
|2001||Celera Genomics and Human Genome Project jointly revealed a blueprint of the human genome.|
|2002||The genome of rice as a crop was revealed.|
|2003||Ending of the Human Genome Project and the chromosomal location of all human genes were established.|
The term biotechnology is so widespread that a comprehensive definition is difficult to formulate. It is extended from conventional biotechnology like the production of alcohol and wine through fermentation, the production of antibiotics by using microbes, the production of different food materials, etc. upto recombinant DNA technology usage in producing genes and proteins for disease therapy. However, the definition of biotechnology was given by various groups in the following manner.
Biotechnology and Its Various Disciplines
Biotechnology has appeared as a branch of general technological science. It may be called as application-oriented knowledge derived from microbiology, taxonomy, physiology, biochemistry, economics, chemical engineering, mathematics, and computer science. As biotechnology is a division of science, it has also several subdivisions, for example, recombinant DNA technology, food technology, fermentation technology, biomining, environmental biotechnology, waste utilization technology, etc.
As engineering and conventional technology both have developed depending on chiefly chemistry and physics, biotechnology has flourished based on biological sciences. The technical procedures such as alcohol and vinegar production through fermentation, bioleaching, treatment of many infectious diseases by antibiotics, vaccines in resisting the prevalence of infective diseases, and production of high-yielding crops through hybridization are different examples of biotechnology in use and these applications are based on biological systems and principles.
Activity in biotechnology may be conveniently broken down into eight areas of endeavour, namely
- Recombinant DNA and genetic engineering
- Cell cultures
- Waste treatment and utilization
- Enzymes and biocatalysts
- Nitrogen fixation
- Fermentation and pharmaceuticals
However, presently recombinant DNA technology and bioprocess engineering occupy the principal positions in biotechnology. The birth of modern biotechnology was possible owing to these two core techniques:
A. Genetic Engineering
Genetic engineering (gene technology or gene engineering), considered a discipline of biotechnology, is the use of in vitro methodology to change the structure of genetic material (DNA and RNA), to design new genes, or to construct chimeric genes (a new gene by fusing two different genes). Genetic engineering includes the technology to transfer these genes into any organism of choice, and to express them in a foreign environment. In basic science, genetic engineering is used to study gene and genome structure and regulation. In industrial applications, genetic engineering serves as a means to provide organisms with new traits to produce more and better chemicals or drugs, or to perform better or additional functions. With the application of recombinant DNA technology, we can prepare a desired gene or its product (proteins or RNA) for human use. A gene may also be altered as per desire and an organism may be altered by transgenic technology. Altogether in five different ways, gene manipulation may be achieved. The different ways are
- Genetic fusion
- Protoplast fusion
- Gene amplification
- Hybridoma production
- Recombinant DNA technology
B. Bioprocess Engineering
Bioprocess engineering is an interdisciplinary science that combines the disciplines of biology and chemical engineering. It is associated primarily with the commercial exploitation of living things on a large scale. The objective of bioprocess engineering is to maintain a sterilized and conducive environment to optimize the growth of desired microbe/eukaryotic cells in large quantities for the generation of targeted biotechnological products. Bioprocess technology is used in the following ways:
- To produce various products related to food and beverages.
- To overproduce essential primary metabolites such as acetic and lactic acids, glycerol, acetone, butyl alcohol, organic acids, amino acids, vitamins and polysaccharides;
- To produce secondary metabolites (metabolites that do not appear to have an obvious role in the metabolism of the producer organism) such as penicillin, streptomycin, cephalosporin, gibberellins, etc.
- To produce many forms of industrially useful enzymes, e.g., exocellular enzymes such as invertase, asparaginase, restriction endonuclease, etc.
- Use cells derived from higher plants and animals to produce many important products, e.g., plant cell cultures are used to produce flavours, perfumes, and drugs; animal cell culture is used to produce vaccines, antibodies, protein molecules such as interferon, interleukins, etc.
Ethics of Biotechnology
It is the condition for the practice of any science that no action should be taken which is against nature and the environment. A progressive work should be aimed at the conservation of biodiversity and sustainable development. When biotechnology refers to the use of living organisms, their products, and processes associated with their life in human welfare, there is a chance of exploitation of our biodiversity. Any disorganized exploitation of the environment and injudicious exploitation of biodiversity in the name of biotechnology may be a threat to human life. Further, the worldwide culture of scientific knowledge is aimed at the sustainable development of society and human beings in general, so the biotechnological application should have a human touch and be eco-friendly. The ethics of biotechnology may be elaborated in the following manner.
- Biotechnology should be based on matters related to living components of the environment.
- Exploitation of nature and threat to biodiversity and human welfare in the name of biotechnology is unethical.
- Traditional knowledge of common people of any region of a country should be avoided from the consideration of biotechnology for patenting.
- Knowledge of biotechnology should be application-oriented but should be used for the welfare of society and civilization and not for making biological weapons.
- Any invention relating to the use of a living organism, its product, or the processes used by it should be brought to light and should be informed to the concerned authority.
Areas of Biotechnology
In a simplified way biotechnology represents the use of a living organism or its cells or the products made by the organism or a cellular method of the organism for human welfare or fulfillment of human desire. Biotechnology may be classified in the following manner.
A. Based on the time of origin
Though biotechnology is quite age-old, it has been developed based on the advancement in various scientific disciplines. Based on the time of origin biotechnology may be divided into two types
1. Old or Traditional or Conventional Biotechnology:
Those practices of biotechnology that are based on the general knowledge and time-tested experience of common people can be categorized as old or traditional biotechnology. Production of curd from milk, wine production through the decomposition of grapes, production of turmeric powder and other spices, bread preparation by using yeast, and production of high-yielding variety.of crops through hybridization etc. are some of the examples of traditional biotechnology.
2. New or Modern Biotechnology:
With the advancement of knowledge in science, the developments achieved in biotechnology are regarded as modern biotechnology. The stage was set for modern biotechnology, based on genetic and cell engineering, to come into being during the 1970s and ’80s. With the advent of information technology, finally, modern biotechnologies gave rise to genomics, proteomics, and cellomics, which promise to develop into the key technologies of the 21st century, with a host of applications in medicine, food and agriculture, chemistry, and environmental protection. Several examples of modern biotechnology are tissue culture, genetic engineering, mutagenesis, production of novel pharmaceutical drugs and antibiotics or chemical products, production of monoclonal antibodies, breeding of transgenic cattle, cloning etc.
B. Based on wideness (dimension)
Modern biotechnology is sufficiently wide in dimension and based on dimension biotechnology may be categorized as green biotechnology, red biotechnology, blue biotechnology, and grey or white biotechnology.
1. Green Biotechnology:
The application of the methodological repertoire of biotechnology to agriculture and plant science is called green biotechnology. Production of transgenic plants and high-yielding varieties of crops comes under green biotechnology.
2. Red Biotechnology:
The application of the methodological repertoire of biotechnology to animal (including human) cells for the development of medical science, either for disease detection or in the promotion of good health is known as red biotechnology. The use of gene therapy and the production of DNA vaccines are included in Red Biotechnology.
3. Blue Biotechnology:
The application of the methodological repertoire of biotechnology to the organisms living in marine or freshwater (preferentially to plants, animals, and microorganisms). Blue biotechnology is used for the development of aquaculture. Transgenic fish production and its culture come under blue biotechnology.
4. White Biotechnology:
The application of the methodological repertoire of biotechnology to microorganisms (predominantly bacteria). White biotechnology aims at the industrial application of technologies (also isolated enzymes, or complete microbes in closed reactor systems) for the production of special biochemicals or biofuels. For example, industrial production of wine, vinegar, and cheese.
5. Black Biotechnology
The application of the methodological repertoire of biotechnology to the engineering of microorganisms (e.g., bacteria, archaea, yeasts) to live on oil (“oil microorganisms”), to produce proteins sensing oil (“prospecting microorganisms”) and to degrade oil (“scavengers”). Microorganisms are selected that convert heavy oil into better manageable light oil (“converters”). The term also encircles wild type and/or genetically modified plants producing substitute oil. For example, the tree legume Pongamiapinnata common to the coastal areas of India, Malaysia, Indonesia, Taiwan, Bangladesh, Sri Lanka and Myanmar, eastern Africa, northern Australia, and Florida produces seeds with about 20-30% oil per seed, that can be refined and used as so-called biodiesel to drive engines.
6. Yellow Biotechnology:
Refers to biotechnology relating to food production. For example making wines, cheese, and beer. Sometimes it is also used for biotechnology applied to insects.
7. Gray Biotechnology:
This is the biotechnology applied to environmental applications such as the maintenance of biodiversity and removal of pollutants using biotechnological approaches. It has reduced the over-exploitation and pollution of the echo system & is used as a remedial methods in protecting the environment.
8. Brown Biotechnology:
It is related to the management of arid lands and deserts.
9. Violet Biotechnology:
Law, ethics, and philosophical issues related to biotechnology are known as violet biotechnology.
10. Dark Biotechnology:
This is related to bioterrorism or biological weapons and biological warfare. Micro-organisms and toxins are used in this to kill humans, livestock, and crops.
11. Gold Biotechnology or Bioinformatics:
It is an interdisciplinary field that is used in the compu¬tational and rapid analysis of biological data.
C. Based on Application and Nature
Biotechnology may be categorized into 4 types based on their application and nature and those are Agricultural biotechnology, Pharmaceutical biotechnology, Industrial biotechnology, and Medical biotechnology.
1. Agriculture Biotechnology:
Biotechnology used in the development of agriculture is known as agriculture biotechnology. Production of genetically modified crops, production of high-yielding varieties of crops and domestic animals, micropropagation, and production of seedlings through tissue culture come under Agricultural Biotechnology.
2. Pharmaceutical Biotechnology:
Pharmaceutical biotechnology deals with the production of medicines or other pharmaceutical products from herbal sources and advanced molecular techniques. Production of monoclonal antibodies with the composition of hybridomas comes under pharmaceutical biotechnology. Production of insulin by using transgenic bacteria is also an example of pharmaceutical biotechnology.
3. Industrial Biotechnology:
Biotechnology related to some industrial production is known as industrial biotechnology. This includes the production of cheese, vinegar, wine, etc.
4. Medical Biotechnology:
Medical biotechnology is the application of molecular technologies to diagnose and treat human diseases. The use of gene therapy and the production of vaccines are two examples of medical biotechnology.
D. Based on Type of Organism
The type of organism used in biotechnology may be a basis for the categorization of biotechnology. In this angle, biotechnology may be divided into three types Microbial Biotechnology, Plant Biotechnology, and Animal Biotechnology.
1. Microbial Biotechnology:
The discipline of biotechnology involves the use of microorganisms such as bacteria and yeast to make valuable products and applications, e.g., the production of insulin with the help of transgenic E. coli.
2. Plant Biotechnology:
The biotechnology developed based on some plant species or their products and used for the development of agriculture and plant science is termed plant biotechnology. It is the application of knowledge obtained from the study of the life sciences to create technological improvements in plant species. For example, the production of pest-resistant plants.
3. Animal Biotechnology:
The biotechnological procedure developed based on some animal species or their products is called animal biotechnology. It is a diverse discipline of biotechnology that involves the use of animals to make valuable products such as recombinant proteins and organs for human transplantation; also includes the generation of transgenic animals or the cloning of animals. For example, the generation of transgenic fish or mice.
Biotechnology and Its Interdisciplinary Approach
Biotechnology is an expensive, interdisciplinary field developed based on our knowledge of chemistry, microbiology, biochemistry, chemical engineering, computer science, & immunology, genetics, physiology, molecular biology, economics, agricultural science etc. Application oriented important technical branches of biotechnology are genetic engineering, protein engineering, immunochemistry, in vitro cell culture, bioprocess technology, etc. A biotechnologist applies his knowledge of these subjects and their principles for the upliftment of human life and the holistic benefit of our society. The principles and application techniques of these disciplines used in biotechnology are known as inputs. The final products that come after the application of biotechnology are called outputs which have much commercial value. Inputs and outputs associated with biotechnology may be shown in the following tree diagram.
A simplified example of the interdisciplinary nature of biotechnology can be summarized as follows. At the basic science level, scientists conducting research in microbiology at a college, university, government agency, or public or private company may discover a gene or gene product in bacteria that shows promise as an agent for treating a disease condition. Typically, biochemical, molecular, and genetic techniques would be used to determine the role of this gene. This process also involves using computer science in sophisticated ways to study the sequence of a gene and analyze the structure of the protein produced by the gene (part of a branch of science called bioinformatics). Once basic research has arrived at a detailed understanding of this gene, the gene may then be used in a variety of ways, including drug development, agricultural biotechnology, and environmental and marine applications.
Scope of Biotechnology
The application of biotechnology is wide. A few important aspects of biotechnology may be shown in the following table.
|Fermentation||Enzymes, Alcohol, Antibiotics, Organic acids, Toxin, Foods – Curd, Cheese, Cake.|
|Tissue Culture||Monoclonal antibodies, Steroids, Somatic embryos, Artificial seeds, etc.|
|Biofuel-bioenergy||Hydrogen, Methane, Biodiesel, etc.|
|Utilization of biomaterials||Proteins, Single-cell proteins, etc.|
|Recombinant DNA technology||Vaccines, Enzymes, Flormones, Antibodies, Transgenic plants and animals, Vitamins etc.|
|Biomedical Engineering||ECG, MRI, EEG, Dialyzer, Heart-Lung machine.|
|Process Engineering||Water recycling, Commercial production related to food process.|
Some Old or Traditional Biotechnology: Some old or traditional biotechnological practices were developed in human society as a culture during prehistoric days and these came into practice based on common sense and age-old experiences of people. Some of the notable old biotechnological practices may be described as follows:
1. Domestication of Plants and Animals
Domestication of plants and animals is an age-old practice. About 10,000 years ago domestication of plants was started by man. At the primary stage cultivation of paddy, barley, and wheat was initiated. After this, the domestication of animals (dogs, lamb, goats, and birds) was started by ancient men to collect milk, meat other products like fur from the animals and feathers from birds.
2. Fermentation in the Production of Foods
Fermentation is most probably the earliest discovery in the biotechnological process. It is an age-old practice of using yeast in the preparation of beer, vinegar, and loaf bread. Our ancestors also knew the method of preparation of curd from milk by using lactic acid. At present, fermentation is used on an industrial basis for the preparation of various food products. In 1897, the enzyme produced from yeast for fermenting organic substances was discovered and since then the enzyme has been used for the production of wine, butanol, acetone, and glycerol. Fermentation has become a tool for the preparation of many medicines and also for the removal of organic wastes from the environment.
3. Food Preservation
For the preservation of food, we mix salt with food material and then they are dried in sunlight. These practices may be cited as examples of traditional biotechnology. Sometimes we store food materials in the cold temperature of the freezer. This is also an example of biotechnology.
4. Selective Plant Breeding
Production of high-yielding varieties of crops and vegetables with the use of superior-quality seeds is quite an acceptable method from the old days. Ever since the beginning of human civilization, farmers have chosen higher-yielding crops by trial and error, so that many modern crop plants have much larger fruits or seeds than their ancestors. This is an example of old biotechnological practice. For this purpose, the cultivators would collect good-quality seeds through selective breeding. The scientific basis of this selective breeding was revealed after the discoveries of G. Mendel.
It is also known as aquafarming which is related to the farming of fishes, crustaceans, mollusks, aquatic plants, algae, and other organisms. This involves the cultivation of freshwater and saltwater populations in controlled conditions. This is also related to capturing of the marine fishes. However, the aquatic fishes and other organisms after their harvesting are marketed for commercial purposes. The practice of aquaculture is an age-old practice of farmers and this includes capture and culture fisheries. For culturing freshwater fishes and other organisms modern methods are being used for better benefit.
Examples of Some Modern Biotechnological Innovations
The foundation of modern biotechnological applications can be traced back to 1866 when Czech monk Gregor Mendel published the results of his experiments on garden peas. He suggested the involvement of some factors in the transfer of traits from one generation to another. Later this factor was determined as the gene.
In 1864 Louis Pasteur, a French chemist, used a microscope for the first time to monitor the fermentation of wine vs. lactic acid. Using sterilized media (“pasteurization”), he obtained pure cultures of microorganisms, thus laying the foundation for applied microbiology and expanding this field into the control of pathogenic microorganisms.
The discovery of penicillin by Alexander Fleming (1922), much later turned into a drug by Howard Florey, initiated the large-scale production of penicillin and other antibiotics during World War II. As early as 1950, more than 1,000 different antibiotics had been isolated and were increasingly used in medicine, animal feeds, and in plant protection.
O.T. Avery, C.M. MacLeod, and M. McCarty (1940) were the pioneers in studying the chemical nature of the substance that was responsible for bacterial transformation. G.W. Beadle and E.C. Tatum (1941) carried out genetic experiments with the bread mould Neurospora crassa with a biochemical slant and established that genes worked through biochemical pathways. They also postulated that each gene was responsible for the synthesis of one particular enzyme.
The whole structure of a protein – insulin, was established by Sanger (1953). Crick and Watson (1953) showed that deoxyribonucleic acid (DNA) had a double-stranded structure. Nirenberg (1963) deciphered the genetic code that was applicable from bacteria to man. The first glucose biosensor was introduced by Leland C. Clark in 1954, initiating a concept for blood glucose monitoring.
Gilbert, Maxam, and Sanger (1976) developed rapid methods for chemical analysis of DNA. Itakura and his co-workers (1977) synthesized the genes of human somatostatin and insulin. N. Goodon and M.D. Chilton (1977) proved that the transfer of genes was possible using the bacterium Agrobacterium tumefaciens as a carrier. H.G. Khorana (1979) succeeded in synthesizing, for the first time, an entirely artificial gene capable of functioning within a living cell.
Kary Mullis (1983) invented Polymerase Chain Reaction (PCR) which revolutionized biotechnological applications. Alec Jeffrey (1984) developed a genetic fingerprinting technique that can be used to identify individuals by analyzing the varying sequences (polymorphisms) in the DNA. In 1995 M. Sehena developed a complementary DNA microarray system to monitor gene expression; also the Institute for Genomic Research reported the first complete DNA sequence of the genome of a free-living organism.
Some of the notable marvels of modern biotechnology are genetic fusion, gene amplification, preparation of hybridoma, and genetic engineering. In every case, genetic alteration happens in microbes, plants, or animals to increase the quality and production of a desired product.
A. Gene Fusion
Gene fusion is the use of recombinant DNA techniques to join (fuse) two or more genes coding for different products so that they are expressed under the control of the same t regulatory system. For example, Gal operon (For galactose metabolism) and biotin operon (for synthesizing biotin) of E. coli are present at different regions of the bacterial chromosome. The regulator gene and controlling elements of bio-operon are present between structural genes of the biotin operon and gal operon. With the help of genetic fusion experiments, the segment of the chromosome containing the regulator gene and controlling elements could be moved and two operons could be combined together. As a result, under the control of the regulator gene of the gal operon, both operons could function together. Therefore, through gene fusion better activity of the genes could be achieved.
Ice-forming Bacteria and Frost
The conversion of water to ice may be “catalyzed” by proteins known as ice nucleation factors. On a microscopic scale, solidifying water forms crystals of ice. However, ice crystals need a microscopic nucleus, or “seed,” to form around. In the absence of structures allowing nucleation, water will supercool down to -8°C without solidifying. Ice nucleation factors are specialized proteins, mostly found in certain bacteria, which provide nuclei for crystallization.
Each year, frost causes more than a billion dollars in damage to crops in the United States alone. When water freezes to form ice, it expands, damaging plant tissues. The seeding of ice crystals on and within the plants is mostly due to proteins on the surface of bacteria, especially Pseudomonas syringae and related species, which live on plants. The ice crystals that form, damage the plant tissues and disrupt the vessels (xylem and phloem) that carry water and nutrients throughout the plant. If ice-nucleating bacteria are absent, ice fails to form and instead, the water supercools, leaving the plants unharmed.
The inaZ gene of Pseudomonas syringae encodes the best-known ice nucleation protein. Like most bacteria, E. coli does not normally promote ice formation, although if it expresses a cloned inaZ gene using a gene fusion technique, it will gain ice-nucleating ability. Conversely, when the inaZ gene of Pseudomonas syringae is disrupted, ice-nucleating ability is lost. The wild, “ice-plus” strains of Pseudomonas syringae can be displaced by spraying the “ice-minus” mutants onto crops that are at risk from frost damage. Subsequently, even if the temperature falls below freezing, very few ice crystals form and most of the plants are unharmed.
Reporter genes are those genes that when introduced into target cells, produce a protein receptor that binds transports or traps a subsequently injected imaging probe. It can be used as marks for screening successfully transfected cells, and for studying the reputation of gene expression. Reporter genes are genes that enable the detection or measurement of gene expression.
If there is no convenient method of recording the activity of a gene (for example, say gene X) of primary interest then the tissue-specific expression of gene X can be monitored by physically fusing the regulatory regions of gene X with a reporter gene, thereby creating a chimeric gene by gene fusion. A reporter gene is any gene that is well characterized both genetically and biochemically and is fused to regulatory regions of other genes to make a chimeric gene, The activity of the reporter gene is then detected in the target organism into which the chimeric gene is transferred. Most reporter gene activities can be easily tested by simple assays (for example, reporter genes often encode enzymes whose activity is easy to assay the enzymatic activity of the protein product, e.g., β-galactosidase, β-glucuronidase, chloramphenicol acetyltransferase, or luciferase) or fluorescence microscopy (e.g., green fluorescent protein and the various analogs).
One of the most widely used reporters is the lacZ gene from E. coli, which encodes the enzyme β-galactosidase. This enzyme splits disaccharide sugar molecules into their monomers but also cleaves various artificial substrates. When the substrate ONPG (Ortho-nitrophenyl-β galacto- side) is cleaved, one of the cleavage products forms a visible yellow dye. When X-Gal is cleaved by β-galactosidase, one of the products reacts with oxygen to form a blue dye.
B. Protoplast Fusion:
The naked plant cell having no cell wall is known as a protoplast (e.g. plant cell walls are digested with a mixture of cellulase, pectinase, and polygalacturonase).
Protoplasts from related plants may easily be combined together. Protoplast fusion is the combination of two related or unrelated protoplasts, or of an enucleated protoplast and a karyoplast to form a hybrid cell by either chemical (with polyethylene glycol or Ca2+) or electrical treatment (electrofusion). Protoplast transformation is the integration of foreign DNA into plant DNA using protoplasts. In bacteria and in other plants beneficial results were obtained by protoplast fusion. If a crop plant having the capability of high productivity but slow growth is combined with a plant having high growth rate but slow productivity, then a plant of high productivity as well as rapid growth may be obtained and this would be an economically better crop plant for cultivation. This sort of result may be obtained by fusing the protoplasts of two kinds of cells. When the protoplasts from two sources are kept in the culture medium, the cells may be fused combining the genetic material of different sources to make a hybrid plant.
Cocking (1960) isolated plant protoplasts enzymatically. Carlson and his group (1972) were the first to fuse the protoplast of Nicotiana glauca and Nicotiana langsdorffii, two sexually compatible species of tobacco, and regenerated a parasexual hybrid. Scientists produced bacterium by fusing cells of two different strains of cephamycin-producing Nocardia lactumdurans and the new bacteria can produce 10-15 times more antibiotics than their parental strains. Protoplast fusion has been used to create broccoflower, a fusion of broccoli and cauliflower, as well as other novel plants. Hence, protoplast fusion may bring forth some profitable results if it is carried out in a planned manner.
C. Gene Amplification
When in a cell, a specific gene is multiplied many times it is known as gene amplification. For the purpose of producing the desired product of a gene in huge amounts, gene amplification may be a helpful mechanism. Bacterial cells sometimes contain extrachromosomal autonomously replicating circular DNA molecules called plasmids. The plasmids may contain some antibiotic-producing genes. If this sort of bacteria is induced in such a way to produce many copies of the antibiotic-producing plasmid, then by using this bacteria huge amount of antibiotic may be produced. Two general methods to amplify a number of plasmids in a bacterial cell are spectinomycin amplification and chloramphenicol amplification.
Spectinomycin amplification (spectinomycin enrichment) is a method to increase the copy number of plasmids in E. coli. The antibiotic spectinomycin inhibits the peptidyl RNA translocation step and therefore bacterial protein synthesis but leaves plasmid replication unaffected. Chloramphenicol amplification (chloramphenicol enrichment) is another method to increase the copy number of plasmids in E. coli. The antibiotic inhibits cellular protein synthesis and thereby chromosome replication but leaves plasmid replication unaffected. Scientists are trying to produce bacterial strains with amplified genes to produce more amount of vitamins, antibiotics, amino acids, and nucleotides.
D. Creation of Hybridoma
Hybridoma is a cell produced by fusing a normal cell with a cancer cell. Such hybridoma was produced first in 1975 by Cesar Milstein and George Kohler when a myeloma cell (a cancer cell) was fused with an antibody-producing B lymphocyte in a HAT medium, the most common selection medium used in the production of hybridomas. Such a hybrid cell could divide endlessly because of the property of the cancer cell and at the same time, the hybrid cells could produce an enormous amount of antibodies owing to its B lymphocytic origin. The antibodies produced by the hybridoma are called monoclonal antibodies. Monoclonal antibodies recognize only one epitope on the antigen and derive from one single B cell. Therefore, hybridoma is a type of engineered cell produced for a particular purpose.
Nowadays, monoclonal antibodies are being used to treat several types of cancer and Crohn’s disease. The first humanized monoclonal antibody approved for clinical use, trastuzumab (Herceptin), was for the treatment of breast cancer in 1998. Remicade (infliximab), which is used to treat rheumatoid arthritis (RA) is another example of another chimeric antibody approved by the FDA. Abzymes are monoclonal antibodies with enzymatic functions that catalyze reactions.
Now scientists are able to produce a hybrid potato plant by producing a hybridoma with a cell from a quality potato plant and a cell from a wild potato plant. Such hybrid plants were found to be pest-resistant. Thus, hybridoma technology has given a new dimension to biotechnology.
E. Recombinant DNA Technology and Genetic Engineering
Recombinant DNA technology is the use of in vitro molecular techniques to manipulate fragments of DNA and produce new arrangements. In 1970, working with the bacterium Haemophilus influenzae, Johns Hopkins University researcher Hamilton Smith isolated Hind III, the first restriction enzyme to be well characterized and used for DNA cloning. This type of enzyme destroys viral DNA in the bacterial cell and restricts the multiplication of phage virus in bacteria. For this reason, the enzymes are called restriction endonucleases.
If any foreign DNA enters the bacterial cell, a restriction enzyme may cleave the foreign DNA at a site containing a 4-6 base specific sequence, on the other hand, such regions of the bacterial DNA remain methylated, so the bacterial own DNA remains protected from the damaging effect of the enzyme. The discovery of these enzymes, which led to Nobel Prizes for W. Arber, H. Smith, and D. Nathans in 1978, was one of the key breakthroughs in the development of genetic engineering.
In 1975, Southern blotting was discovered. The technique can recognize a DNA sequence or gene from the intermediate position of a long DNA and also helps to separate the region from the source DNA. Because of this, it is also a landmark discovery in recombinant DNA technology. It the last part of 1970, the mechanism of artificial synthesis of oligonucleotides was discovered. Besides, expression of genes from eukaryotes in the prokaryotic cells was made possible during this period and this was a landmark event in the progress of recombinant DNA technology.
Gene editing methods involve the use of specifically engineered DNA-modifying enzymes (nucleases) that allow researchers to create changes in a specific sequence to remove, correct, or replace a defective gene or parts of a gene. Gene editing is based on using different nucleases to create breaks in the genome in a sequence-specific manner using various tools like zinc-finger nuclease (ZFN), transcription activator-like effector nuclease (TALEN), and CRISPR (clustered regularly interspaced palindromic repeats) – Cas techniques.
Significant practical applications of recombinant DNA technology also have been developed, including exciting advances such as gene therapy, screening for human diseases, recombinant vaccines, and the production of transgenic plants and animals in agriculture, in which a cloned gene from one species is transferred to some other species.
Several notable discoveries in recombinant DNA technology:
|1. In vitro gene synthesis, restriction endonuclease||1970||Herbert Boyer|
|2. Recombinant DNA||1972||D.A. Jackson, R.H. Symons and Paul Berg|
|3. Gene cloning||1973||Stanley Cohen and Herbert Boyer|
|4. Southern blotting||1975||E.M Southern|
|5. PCR||1983||Kary Mullis|
|6. Gene gun||1987||John Sanford, Ed Wolf, and Nelson Allen|
|7. Monoclonal antibody||1995||Georges Kohler, Cesar Milstein|
|8. Cloning of sheep||1998||Ian Wilmut|
Difference between Traditional Biotechnology and Genetic Engineering:
|Traditional Biotechnology||Genetic Engineering|
|1. Generally very old biotechnological practices were used before the 20th century.||1. Comparatively new techniques of biotechnology in use after the 20th century.|
|2. Developed based on experience and common sense of people.||2. Developed based on knowledge from scientific experiments.|
|3. The technology usually uses some microbes or the inner potentiality of a microbial organism.||3. The technology utilizes some genetic alteration of an organism.|
|4. Less efficient||4. More efficient|
|5. No genetic alteration is made.||5. Normally associated with genetic alteration.|