Biotechnology: Principles and processes
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 contaminationfree
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).
Construction of a Recombinant DNA
● Plasmid (autonomously replicating, circular, extrachromosomal 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 antibiotic
resistance genes and one will be able to isolate the recombinants.
Restriction
Enzymes as Tools of RDT
● Restriction enzymes are specialised enzymes that recognise and cut a
particular sequence of DNA.
● Nucleases are of two types:
○ Endonucleases − Cut the DNA at specific positions within the
DNA
○ Exonucleases − Cut the DNA at the ends (Remove the
nucleotides at the ends of the DNA)
● Every restriction enzyme identifies different sequences (Recognition
sequences). Over 900 restriction enzymes have been isolated, all of
which recognise different sequences.
● Recognition sequences are
pallindromic
Pallindromes are the
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 contaminationfree
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).
Construction of a Recombinant DNA
● Plasmid (autonomously replicating, circular, extrachromosomal 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 antibiotic
resistance genes and one will be able to isolate the recombinants.
Restriction
Enzymes as Tools of RDT
● Restriction enzymes are specialised enzymes that recognise and cut a
particular sequence of DNA.
● Nucleases are of two types:
○ Endonucleases − Cut the DNA at specific positions within the
DNA
○ Exonucleases − Cut the DNA at the ends (Remove the
nucleotides at the ends of the DNA)
● Every restriction enzyme identifies different sequences (Recognition
sequences). Over 900 restriction enzymes have been isolated, all of
which recognise different sequences.
● Recognition sequences are
pallindromic
Pallindromes are the
