Economic importance of Viruses
Discipline Courses-I
Semester-I
Paper: Phycology and Microbiology
Unit-IV
Lesson: Economic importance of- Virus
Lesson Developer: Pamela Singh
College/Department: Dept. of Biotechnology, Deen Bandhu
Chhotu Ram University of Science and Technology
Institute of lifelong learning, university of Delhi 0
, Economic importance of Viruses
Table of contents
Chapter: Economic importance of Viruses
Introduction
Medicine and Diagnostics
Vaccine Production
Gene Therapy
o Ex-vivo somatic gene therapy
o In-vivo somatic gene therapy
o Germ line gene therapy
Cancer Therapy
Bacteriophage therapy
Role of Viruses in Diagnosis
Role of Viruses in Research
Viruses as biopesticides
Viruses as causal Organisms of plant
diseases
Summary
Glossary
Exercises
References
Institute of lifelong learning, university of Delhi 1
, Economic importance of Viruses
Introduction
A virus, as we now know is a very small sized acellular infectious agent which can
replicate only inside a living host. Viruses are so small in size that they can easily pass
through bacterial filters .They either have a limited number of enzymes or none at all as
their metabolic machinery. Thus they have to depend completely on their host for
survival and replication. The viruses have a very broad host range i.e. they can infect
humans, animals, plants, bacteria, fungi,etc. Viruses are common human pathogens
causing a number of deadly diseases like AIDS,Herpes,Cancer etc.
Viruses have been primarily identified as pathogens but they also have significant
economic importance.
Viruses act as simple systems, which can be used as tools for research and
analysis. Studies on recombinant DNA technology were developed using
bacteriophages (Bacterial Viruses).
In addition, the viral genomes were the first ones to be sequenced (øx174 and
MS 2).
The lysogenic life cycle of certain viruses allows easy manipulation of the viral
genome. Viruses are used as vectors to deliver therapeutic genes into humans in
gene therapy. They are also used to cure cancer in a number of ways like
virotherapy and VDEPT (virus directed enzyme pro drug therapy).
Viruses are also the primary sources of vaccines used to prevent the viral
infections.
Some of the viruses can also be used for the control of insect pests of our crop
plants. However, in contrast a number of viruses are important plant pathogens
as will be discussed in the subsequent text.
Medicine and Diagnostics
Vaccine production: Viral vaccines confer immunity against infection by the
pathogenic strains of the same viruses. The initial research on vaccines by Edward
Jenner (1796) started with a virus. Jenner used the cowpox virus (now known as
vaccinia virus) as a live vaccine for preventing smallpox. The conventional vaccines
synthesized using live attenuated viruses or killed viruses are easy to produce and
economic but have a number of disadvantages. Reversion of the live attenuated viral
Institute of lifelong learning, university of Delhi 2
Discipline Courses-I
Semester-I
Paper: Phycology and Microbiology
Unit-IV
Lesson: Economic importance of- Virus
Lesson Developer: Pamela Singh
College/Department: Dept. of Biotechnology, Deen Bandhu
Chhotu Ram University of Science and Technology
Institute of lifelong learning, university of Delhi 0
, Economic importance of Viruses
Table of contents
Chapter: Economic importance of Viruses
Introduction
Medicine and Diagnostics
Vaccine Production
Gene Therapy
o Ex-vivo somatic gene therapy
o In-vivo somatic gene therapy
o Germ line gene therapy
Cancer Therapy
Bacteriophage therapy
Role of Viruses in Diagnosis
Role of Viruses in Research
Viruses as biopesticides
Viruses as causal Organisms of plant
diseases
Summary
Glossary
Exercises
References
Institute of lifelong learning, university of Delhi 1
, Economic importance of Viruses
Introduction
A virus, as we now know is a very small sized acellular infectious agent which can
replicate only inside a living host. Viruses are so small in size that they can easily pass
through bacterial filters .They either have a limited number of enzymes or none at all as
their metabolic machinery. Thus they have to depend completely on their host for
survival and replication. The viruses have a very broad host range i.e. they can infect
humans, animals, plants, bacteria, fungi,etc. Viruses are common human pathogens
causing a number of deadly diseases like AIDS,Herpes,Cancer etc.
Viruses have been primarily identified as pathogens but they also have significant
economic importance.
Viruses act as simple systems, which can be used as tools for research and
analysis. Studies on recombinant DNA technology were developed using
bacteriophages (Bacterial Viruses).
In addition, the viral genomes were the first ones to be sequenced (øx174 and
MS 2).
The lysogenic life cycle of certain viruses allows easy manipulation of the viral
genome. Viruses are used as vectors to deliver therapeutic genes into humans in
gene therapy. They are also used to cure cancer in a number of ways like
virotherapy and VDEPT (virus directed enzyme pro drug therapy).
Viruses are also the primary sources of vaccines used to prevent the viral
infections.
Some of the viruses can also be used for the control of insect pests of our crop
plants. However, in contrast a number of viruses are important plant pathogens
as will be discussed in the subsequent text.
Medicine and Diagnostics
Vaccine production: Viral vaccines confer immunity against infection by the
pathogenic strains of the same viruses. The initial research on vaccines by Edward
Jenner (1796) started with a virus. Jenner used the cowpox virus (now known as
vaccinia virus) as a live vaccine for preventing smallpox. The conventional vaccines
synthesized using live attenuated viruses or killed viruses are easy to produce and
economic but have a number of disadvantages. Reversion of the live attenuated viral
Institute of lifelong learning, university of Delhi 2
