The European Federation of Biotechnology [EFB] has defined biotechnology as The integration of natural science and organisms. Cells, parts, and molecular analogues for products and services.
BIOTECHNOLOGY deals with techniques of using organisms or enzymes from organisms to produce products and processes useful for human welfare.
TWO CORE TECHNIQUES ARE INCLUDED IN MODERN BIOTECHNOLOGY:
1. GENETIC ENGINEERING
2. MAINTENANCE OF STERILE AMBIENCE / CONDITIONS
1. GENETIC ENGINEERING:
This includes modification of genetic material of organism using alien or foreign DNA. Recombinant DNA technology has made it possible to transfer gene or piece of DNA from one organism to another.
RDT uses RESTRICTION ENDONUCLEASE ENZYMES which cut the DNA at a specific sequence called recognition sequence or restriction site.
BELOW IS A LIST OF SOME RESTRICTION ENDONUCLEASE WITH THEIR RECOGNITION SITE:
Today we know more than 900 restriction enzymes that has been isolated from over 230 strains of bacteria each with different restriction site. RESTRICTION or RECOGNITION SITES are PALINDROMIC NUCLEOTIDE SEQUENCE IN DNA. PALINDROMES are sequences in which first half is the mirror image of second half. Restriction enzymes cut the phosphodiester linkage in the recognition site. Recognition sites are 4 to 8 nucleotide long sequences.
These enzymes are named restriction endonuclease because they restrict the growth of viral DNA that might enter the cell, during infection. Thus, R.E. serves as a defence mechanism and bacteria protects its own DNA from nucleolytic attack by methylation of its own chromosome.
When cut by a restriction endonuclease, TWO TYPES of sequences are formed.
1. sticky ends or staggered cuts or cohesive ends
2. blunts ends
