Bacillus thuringiensis is a bacterium that produces proteins toxic to certain insects. The first Bt corn was registered with the EPA in 1995. Bt corn provides over 99% control of European corn borers through Cry proteins in plant tissues that form pores in the insect's gut, causing paralysis and death.

1. BT Corn
Carla Barrios
Jim Taylor

2. BACILLUS THURINGIENSIS IS A SPECIES OF BACTERIA THAT PRODUCES
(CRYSTAL-LIKE)PROTEINS THAT ARE TOXIC TO CERTAIN INSECTS.

3. BT History
 Japanese biologist Shigetane Ishiwatar
isolated the bacterium Bacillus thuringiensis
(Bt) in 1901.
 In 1915, Ernest Berliner reported the
existence of a crystal within Bt.
Farmers started to use Bt as a pesticide in
1920, but only killed flour moth.

4. Bt as a pesticide had limitations such as it is
washed away by rain and degraded by UV
light.
In 1958 Bt was used commercially in United
States and was registered as a pesticide to the
EPA in 1961.
In 1977 thirteen Bt strains had been described
and were toxic to certain species of
lepidopteran larvae.

5.  In the 1980's use of Bt increased when insects
became increasingly resistant to the synthetic
insecticides.
Scientists and environmentalists became
aware that the chemicals were harming the
environment.
The first genetically engineered plant, corn,
was registered with the EPA in 1995.

6. How BT works
When a susceptible insect ingests plant material containing the Bt toxin, pores in a section of the midgut of the
insect are formed. This then leads to paralysis of the gut and within two to three days, death of the insect.

7. Advantages
 Bt does not kill beneficial insects such as
honeybees.
 Bt is essentially nontoxic to people, pets and
wildlife.
 Bt does not has negative impact on the
environment.
 Bt provides more than 99% control of first
generation European corn borer larvae.

8. How it’s made
DIY BT CORN

9. Overview

10. Planning
Gene: Bt
a Promoters - 35S or PEP Carboxylase
b. Coding Regions - Cry1A(b), Cry1A(c), or
Crygc
c. Expression - If 35S promoter; then ECB
resistance in all tissues all the time.
If PEP Carb_ promoter, then ECB resistance in
actively photosynthesizing (green) tissues on y.
Gene: Roundup resistance
a Promoter - 35S
b. Coding Region - EPSPS enzyme (Roundup
resistance) + CTP region to send protein to
chloroplasts
c. Expression - Roundup resistance in all plant
tissues all the time.

11. The Process

12. Isolating
the gene

13. The Genes

14. Selecting restriction enzymes

17. The Vector

19. Building
the
Plasmid

21. Getting it into
the maize cell

23. The Corn
T0940A Hi-II Parent A (for producing embryogenic callus cultures)
(also known by these names: Hi IIA, Hi-II Parent A, HiII A, HiIIA, High 2, High II, High-2, High-
II, High2, HighII,T0940A, T940A Hi-II Parent A)
Partially inbred line selected out of a cross between A188 and B73 Obtained from C.
Armstrong. For producing embryogenic (Type II) callus cultures.

24. Excise the
embryos by
inserting the
narrow end of a
sharpened
spatula between
the endosperm
and pericarp

28. Growing
it out

30. Summary
Impact
Building

31. Impact
Bacillus thuringiensis is a species of bacteria that produces (crystal-like)proteins that are toxic to
certain insects.
Japanese biologist Shigetane Ishiwatar isolated the bacterium Bacillus thuringiensis (Bt) in
1901.
The first genetically engineered plant, corn, was registered with the EPA in 1995.
Bt provides more than 99% control of first generation European corn borer larvae

32. Overview

33. Partial list of references.
The full list is available upon request.
1. National Center for Biotechnology Information - http://www.ncbi.nlm.nih.gov/
2. SnapGene tutorial videos - http://www.snapgene.com/support/tutorial_videos
3. New England Biolabs - https://www.neb.com/tools-and-resources/interactive-tools/dna-sequences-and-
maps-tool
4. MaizeGDB! - http://alpha.maizegdb.org/
5. http://gmoinfo.jrc.ec.europa.eu/gmp_report.aspx?CurNot=B/RO/09/03
6. http://www.ent.iastate.edu/pest/cornborer/
7. http://www.fda.gov/Food/FoodScienceResearch/Biotechnology/Submissions/ucm121422.htm
8. http://www.fda.gov/food/foodscienceresearch/biotechnology/submissions/ucm161150.htm
9. http://www.livestrong.com/article/373830-how-to-choose-restriction-enzymes/