BIOTECHNOLOGY IS the manipulation of biological systems to manufacture important foods, drugs, biopolymers and other materials. This is illustrated below by the production of the protein human insulin in bacterial
culture:
Small circles of DNA exist in bacteria, known as plasmids. These are modified
to include the piece of human DNA containing instructions for making proinsulin.
Proinsulin is the precursor for insulin.
The plasmid is then inserted into Eschericia coli (E. coli) bacteria, which
can now produce human proinsulin.
Bacteria multiply and produce large quantities of human proinsulin in a
fermentor.
Bacteria are then killed by heat sterilisation, leaving behind the proinsulin.
Proinsulin is enzymatically cleaved to produce human insulin. Enzymatic
cleavage is the slicing of a molecule by a protein.
The solution is centrifuged to remove cell matter and purified by liquid
chromatography and crystallisation.
Insulin is a hormone produced by the pancreas, and is essential for the regulation of glucose in the body. The pancreas of a diabetes patient has lost the ability to produce insulin. Prior to the development of the above biotechnology process in the 1980s, only animal insulin (usually from slaughtered pigs) was available to diabetics in limited quantities.
http://www.che.utoledo.edu/Biotechnology.html
Dr. Sylvia Mitchell, scientific officer, Biotechnology Centre, University of the West Indies, Mona, email: smitchel@uwimona.edu.jm.
