Biotechnology : Principles and Processes

Introduction to Biotechnology

What is biotechnology?

• Biotechnology refers to the technology using biology, which has applications in agriculture, food processing industry, medicine diagnostics, bioremediation, waste treatment, and energy production.

• The European Federation of Biotechnology (EFB) defines biotechnology as “the integration of natural science and organisms, cells, parts thereof and molecular analogues for products and services”.

Basis of Modern Biotechnology

• Genetic engineering − Introduction of foreign genetic material (DNA/RNA) into the host’s genome and altering its phenotype

• Aseptic techniques − Involves maintenance of contamination-free ambience in chemical engineering processes for manufacture of products such as antibiotics, vaccines, etc.This is done so as to enable the growth of only desired microbes responsible for a bioprocess.

Genetic Engineering

• Asexual reproduction preserves the genetic information while sexual reproduction preserves variations.

• Plant and animal hybridization procedures often result in introduction of undesirable genes along with desirable ones.

• Genetic engineering overcomes this limitation.

• Genetic engineering includes:

  • Creation of recombinant DNA

  • Gene cloning

  • Gene transfer into host organism

• The introduced piece of DNA does not replicate in the host unless it is integrated with the chromosome of host.

• For getting replicated, the foreign DNA must integrate into the host DNA sequence having ‘origin of replication’. When this integration occurs, foreign DNA is replicated and many copies are formed. This process is called cloning (the process of formation of multiple identical copies of DNA).

• Plasmid (autonomously replicating, circular, extra-chromosomal DNA) is isolated.

• Plasmid DNA acts asa vector since it is used to transfer the piece of DNA attached to it to the host.

• Plasmid DNA also contains genes responsible for providing antibiotic resistance to the bacteria.

• Plasmid DNA was cut with a specific restriction enzyme (‘molecular scissors’ − that cut a DNA at specific locations).

• The DNA of interest (to be inserted) was also cut with the same restriction enzyme.

• The DNA of interest is hybridised with the plasmid with the help of DNA ligase to form a Recombinant DNA.

•  Recombinant DNA is then transferred to a host such as E.coli, where it replicates by using the host’s replicating machinery.

• When E.coli is cultured in a medium containing antibiotic, only cells containing recombinant DNA will be able to survive due to…