Biotechnology deals with techniques of using live organisms or enzymes from organisms to produce products and processes useful to humans. In this sense, making curd, bread or wine, which are all microbe-mediated processes, could also be thought as a form of biotechnology. However, it is used in a restricted sense today, to refer to such of those processes which use genetically modified organisms to achieve the same on a larger scale. Further, many other processes/techniques are also included under biotechnology. For example, in vitro fertilisation leading to a ‘test-tube’ baby, synthesising a ene and using it, developing a DNA vaccine or correcting f defective gene, are all part of biotechnology. The i ‘ederation of Biotechnology (EFB) has given a defiriition of biotechnology that encompasses both traditional view and modern molecular biotechnology. The definition given by EF is as follows: ‘The integration of natural science and organisms, cells, parts thereof, and molecular analogues for products and services’. 9.1 Principtes or BiorecHNoLocy ‘Among many, the two core techniques that enabled birth ‘of modern biotechnology are : (i) Genetic engineering : Techniques to alter the chemistry of genetic material (DNA and RNA),__ Permits variation. Traditional hybridisation procedure: _ animal breeding, very often lead to inclusion and phenotype of the host organism. (i) Bioprocess engineering: Maintenance of sterile i contamination-free) ambience in chemical engineerin, pba to enable growth of only the desired microbe/eukaryoti.,. large quantities for the manufacture of biotechnology like antibiotics, vaccines, enzymes, etc. Let us now understand the conceptual development of the of genetic engineering. You probably appreciate the advantages of sexual reproduction Over asexual reproduction. The former provides opportunities for Variations and formulation of unique combinations of genetic setup, some of. which may be beneficial to the organism as well as the Population. Asexi2j reproduction preserves the genetic information, while sexual reproduction S used in plant and ~ anu thus Change i he te cel j in cal Products Princ; ples this limitation and allows us and introduce only one or a set undesirables'— restriction enzymes. ‘The eut o4 ith the plasmid DNA. These plasmid DNA. wie claaiee of DNA attached to it. You probably know that mosquito sect vector to transfer the malarial parasite into human body. yy. a plasmid can be used as vector to deliver an alien piece host organism. The linking of antibiotic resistance gene asmid vector became possible with the enzyme DNA ligase, cut DNA molecules and joins their ends. This makes a new of circular autonomously replicating DNA created in vitro as recombinant DNA. When this DNA is transferred into coli, a bacterium closely related to Salmonella, it could ing the new host's DNA polymerase enzyme and make multiple ability to multiply copies of antibiotic resistance gene in cloning of antibiotic resistance gene in E. coli. infer that there are three basic steps in genetically organism — of DNA with desirable genes; of the identified DNA into the host; ce of introduced DNA in the host and transfer of the DNA or Recompinant DNA Tecunovocy from the foregoing discussion that genetic engineering or DNA technology can be accomplished only if we have the restriction enzymes, polymerase enzymes, ligases, vectors organism. Let us try to understand some of these in detail. on Enzymes 1963, the two enzymes responsible for restricting the growth in Escherichia coli were isolated. One of these added DWA, while the other cut DNA. The later was called p endonuclease-Hind II, whose functioning DNA nucleotide sequence was isolated and , It was found that Hind IJ always cut DNA F point by recognising a specific sequence of pecific base sequence is known as the Hind Il. Besides Hind II, today we know more hhave been isolated from over 230 strains