20.1) Biotechnology and genetic engineering
- Biotechnology is the application of biological organisms, systems or processes to manufacturing and service industries.
- Genetic engineering involves the transfer of genes from one organism to (usually) an unrelated species.
- Both processes often make use of bacteria because of their ability to make complex molecules (eg. proteins) and their rapid reproduction rate.
- Bacteria are useful in biotechnology and genetic engineering because they can be grown and manipulated without raising ethical concerns.
- They have a genetic code that is the same as all other organisms, so genes from other animals or plants can be successfully transferred into bacterial DNA.
- Bacterial DNA is in the form of a circular strand and also small circular pieces called plasmids.
- Scientists have developed techniques to cut open these plasmids and insert sections of DNA from other organisms into them.
- When the bacterium divides, the DNA in the modified plasmid is copied, including the ‘foreign’ DNA.
This may contain a gene to make a particular protein such as insulin, which can be extracted and used as a medicine to treat diabetes.