What do you mean by Biotechnology?
Biotechnology is the fusion of Biology with Technology. It deals with the techniques of using microorganisms, plant or animal cells or their components to generate products and services (processes) useful to human beings.
Modern biotechnology refers to those processes/production technologies which use the technique of genetic manipulation, artificial gene synthesis in vitro fertilization, etc...
Definition of Biotechnology:
The European Federation of Biotechnology (EFB) defines biotechnology as the integration of natural science and organisms, cells, parts there of and molecular analogues for products and services.
2. Principles of Biotechnology
The two core techniques that enabled the birth of modern biotechnology are the following.
(i)Genetic engineering : the technique of chemical alteration of the genetic material of an organism by introducing, replacing or deleting genes in order to change its phenotype.
(ii)Chemical engineering processes :Techniques to facilitate the growth and multiplication of only the desired microbes or cells in large number, under sterile conditions for the manufacture of biotechnological products like antibiotics, enzymes etc.
Conceptual development of the principles of genetic engineering:
Ø The technique of genetic engineering is different from traditional Hybridization that it excludes the introduction of undesirable genes into the target organisms as it involves creation of recombinant DNA, gene cloning and gene transfer to target organism.
Ø As compared to traditional hybridisation method, the technique of genetic engineering is preferred as it permits to isolate only the desirable gene/s and introduce it into the target organism.
Ø The desired piece of DNA which has been introduced into the alien (foreign) organism is called the Insert (and it would not be able to multiply itself.
Ø Insert can multiply only when it gets integrated into the genetic material of the recipient organism (host organism). This is because the alien (foreign) piece of DNA has now become the part of a recipient chromosome which possesses the ability to replicate. The specific DNA sequence present in the chromosome responsible for initiation of replication is called the origin of replication.
Ø The process by which the alien DNA linked with origin of replication, replicates and multiplies in the host organism is called cloning i.e., formation of multiple genetically identical copies of any template DNA.
Construction of the first artificial recombinant DNA molecule:
The present day DNA technology has its roots in the experiments performed by Herbert Boyer and Stanley Cohen in 1972.
They successfully recombined two plasmids (pSC101 containing tetracycline resistant gene and pSC102 containing kanamycin resistant gene) as the first artificial recombinant DNA molecule in E.coli..
It included the following steps.
(1) In the year 1972, Stanley Cohen and Herbert Boyer, the two scientists of USA, isolated an antibiotic resistant gene from a plasmid of the bacterium Salmonella typhimurium. This piece of DNA was responsible for conferring antibiotic resistance.
(2) These two workers isolated the antibiotic resistance genes by cutting the desired piece of DNA from the plasmid.
(3) Cutting of a piece of DNA from a plasmid was done with the help of restriction enzymes, popularly known as 'molecular scissors'.
(4) The piece of DNA cut from the plasmid was then linked with the plasmid DNA acting as vector. Linking of the fragment of DNA with vector was done with the help of another enzyme – called the DNAligase, which acts on cut DNA molecules and join their ends.
(5) This newly formed DNA having integrated fragment of antibiotic resistant gene is called recombinant DNA.
(6) Vectors are used to transfer recombinant DNA to bacterium Escherichia coli.
(6) Once the newly formed recombinant DNA was transferred to bacterium E. coli, it replicates in host cell by using the enzyme DNA polymerase.
(8) It results in the formation of several copies of recombinant DNA having capability of antibiotic resistance. The process of multiplication of gene (or a piece of DNA) is called Gene cloning.
Recombinant DNA technology, popularly known as 'genetic engineering', is that aspect of biotechnology which deals with the in vitro manipulation of genetic material.
It refers to a number of methodologies in which the desired genes or DNA sequence of an organism are cut into fragments and then introduced into host cells with or without the help of carriers or vectors to alter its phenotype.( to suit human needs.)
- Jackson Achankunju: Jackson Achankunju
Principles and Processes of Biotechnology
