Transcript Introduction to Biotechnology

Vaccines, Clones
&Transgenics
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Plant vaccines contain dead or
weakened strains of plant virus
which are injected to plants
against diseases
Vaccines can also be encoded in
plant DNA
Transgenic plants can synthesize
protein antigens that retain
immunological properties
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The Tobacco Mosaic virus (TMV),
produces a protein on surface of
the virus which turns on the plant
immune system in tobacco plants
Tobacco plants with TMV has the
resistance against the virus
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With the advent of modern
molecular biology techniques in
the 1980s, new strategies were
developed for the production of
subunit vaccines
Green plants are used as the
“surrogate production organism”
to produce antigens of human
pathogens
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Rabies virus G-protein in tomato
Norwalk virus Capsid protein in
tobacco & potato
Hepatitus B virus surface antigen
in tobacco & potato
E.coli heat-labile enterotoxin B
subunit (LT-B) in tobacco & potato
Cholera toxin B subunit (CT-B) in
potato
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Eaten raw
Appealing to children
Inexpensive to produce
Native to many developing
countries
Still under clinical trials
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The BT gene in Bacillus thuringiensis ,
produces a crystalline protein that kills
insects and their larvae (an
insecticidal protein).
Instead of spreading the bacteria in the
field now can spread Bt genes!!!
Tomatoes, potatoes, corn , cotton etc.
Today, plants can be genetically
engineered to produce their own Bt
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Crops are genetically engineered to be
resistant to common herbicide called
glyphosate( an enzyme which block
photosynthesis)
Generally herbicides are used to kill
weeds and by doing so, crops get
affected.
Hence the need for genetically
engineered herbicide resistant crops
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Deficiency of Vitamin A causes
night blindness.
Genetically engineered rice to
produce large amount of Beta
carotene, a provitamin which body
converts to Vitamin A.
Read pg 144 test book for further info
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http://www.nal.usda.gov/bic/BTTO
X/bttoxin.htm
http://www.ag.uiuc.edu/~vista/html
_pubs/biotech/insect.htm