Transcript Biotechnology - BHSBiology-Cox

Introduction to
Biotechnology!
Defining Biotechnology
Biotechnology- the study and
manipulation of living things or their
component molecules, cells, tissues, or
organs.
The beginning of biotechnology
• Humans have been manipulating living things for
thousands of years
• Selective breeding- manipulating living things with
desired characteristics
• Why?
• Examples?
Beginning of Biotechnology
• Over 100 breeds of dogs created through selective
breeding
Beginning of Biotechnology
• Different varieties of apples commonly found in
grocery stores
Beginning of Biotechnology
• Range of size, color, and fragrance for a
variety of roses
Beginning of Biotechnology
• Cows, goats, sheep, and chickens for milk, meat,
and egg production
Beginning of Biotechnology
• Fermentation of foods
and beverages
The 1970’s
• Scientists began experimenting with molecules,
cells, tissues, and organs (moving away from entire
organisms). WHY?
• New technologies are applied to the research and
development of products from plant and animal
tissues
• The term “Biotechnology” was coined
Biotechnology today
• Focuses on DNA, not
RNA or proteins
– Manipulate at the earliest
source possible (very
difficult to control
outcome later)
The Central Dogma of Biology.
Uses The Central Dogma of Biology. Moving genes into
cells to produce new proteins is the basic principle in
genetic engineering.
The Increasing Variety of
Biotechnology Products
“In the past 100 years, scientists have increased the pace
of searching for products that improve the quality of life.”
As the methods of manipulating livings have become more
sophisticated, the number and variety of biological products have
increased at an incredible rate
Recent uses of biotechnology
• Insulin- made in bacteria cells to
treat diabetes
• Originally insulin was harvested from
the pancreas of a slaughtered animal
for treatment
Recent uses of biotechnology
• Proteases- proteins that break down other
proteins
• Commonly used in stain removal products
Recent uses of biotechnology
• Antibiotics- proteins developed by the immune
system that recognize a specific molecule
(antigen)
• Used to fight diseases
Recent uses of biotechnology
• Indiage- protein (enzyme)
that causes denim to fade
to produce
“stonewashed”
appearance
Recent uses of Biotechnology
• Mouse cells “tricked” into growing outer portion of a human
ear which can be surgically transferred to a human patient
Recent Advances in Biotechnology
come from Manipulation of DNA!
What do you think of when you hear
this?
Types of Genetic Manipulation
• 1.Recombinant DNA (rDNA) technology- cutting
and recombining DNA molecules
E. Coli
transformation
What Makes rDNA Possible?
• Polymerase Chain Reaction or PCR: copying
short pieces of DNA (genes)
• Restriction enzymes – cuts nucleotide sequence
at specific sites on DNA molecule
• Gel Electrophoresis: Separate DNA fragments by
size
• DNA ligase – enzyme that pastes DNA molecules
together allowing for new combinations
Gel Electrophoresis
Gel Electrophoresis
• Electrophoresis allows separation of
molecules in an electrical field on the basis of
size/molecular/weight and shape.
• A molecule with a negative charge (anion) will
migrate toward the positive electrode (anode),
and a molecule with a positive charge (cation)
will migrate toward the negative electrode
(cathode)
• The migration and separation of molecules are
carried out using a solid matrix (i.e. agarose,
polyacrylamide).
• The matrix retards the movement of molecules
by a seiving effect – small molecule navigate
the matrix more quickly than larger ones.
Gel Electrophoresis
• Electrophoresis is used chiefly for analysis and
purification of large molecules such as nucleic
acids, but can be a applied to any charged
molecules.
• The relative mobility of the fragments– how fast
they travel though the matrix relative to each other
- will depend on several parameters.
Gel Parameters
• Migration through the gel can be effected by:
•
•
•
•
Size
Shape
% Agarose
Voltage
Gel Parameters
• Size
– Smaller fragments of DNA will travel further than the larger
ones.
• Shape
– DNA can roll into a ball, making it migrate faster. In
addition, if damaged, it will migrate slower.
• % Agarose
– Fragments larger than the matrix pore size cannot enter
the gel and are not resolved. At the other extreme,
fragments smaller than the pore size are not retarded at
all.
Gel Parameters
 Voltage
In addition to Ohm’s law (V=IR), a
fundamental equation in
electrophoresis is the power
equation
P=VI
The higher the voltage, the
greater the power – heat!
• gel melts
• Non-uniform heat
distribution results in
smiling bands (heat is
more rapidly dispersed at
edges of gel)
5 – 8 cm /V
Gel Electrophoresis
• Loading dye
– Glycerol (gives weight to the DNA sample so it will not float
out well of the gel into the buffer)
– Dye (so we can see the DNA enter the gel and migrate)
• Visualization
– Ethidium Bromide is a dye that intercalates between the
base of nucleic acids. When exposed to UV light, it will
fluoresce, making the DNA visible.
– We will then find the size of the DNA fragments, and
determine the quality and quantity of DNA we have
Markers
A DNA marker, a sample of DNA
fragments of known sizes and mass,
is used as a reference to estimate
the size of unknown DNA
molecules.
You run it on the gel with the DNA
samples and compare the sizes of
your fragments to the sizes of these
known fragments
Quality and Quantity Assessment
Quality: Is the band a
distinct band or a
smear? A smear
indicates broken or
degraded DNA.
Quantity: How bright is
the band. The brighter
the band=the more
DNA
Steps of rDNA?
• 1. Use Restriction Enzymes to remove the gene of interest from an
organism that produces it naturally.
• 2. Use Gel Electrophoresis to resolve fragments.
• 3. Copy the gene of interest millions of times with PCR.
• 4. Use Restriction enzymes to cut the DNA of the organism that will
receive the gene of interest. Again, use gel electrophoresis to
resolve fragments.
• 5. Use DNA ligase to seal the new gene into the receiving
organism. Use gel electrophoresis to confirm size of DNA.
Steps of rDNA
• Production of rDNA can be done directly or with the
use of plasmids
• Plasmids – tiny circular pieces of DNA usually from
bacteria that is used to insert recombinant DNA into
an organism
rDNA to GMO
Restriction enzymes, Gel Electrophoresis,
DNA ligase, and plasmids:
• Make Recombinant DNA – DNA created from
two or more sources
leads to
• Genetically modified organism (GMO) –
organism that contains DNA from another
organism and produces new proteins
encoded on the acquired DNA
What is Genetic Engineering?
•
Genetic engineering refers to the
modification of genetic material to
achieve specific goals
•
We can modify organisms to
express genes they never had and
make proteins they never have
before= A GENEATICALLY
MODIFIED ORGANISM
What is the Difference Between rDNA
and a GMO
• rDNA: Just the DNA has been genetically
modified
– DNA of 2 organisms spliced together
• GMO: the genome of an organism has been
genetically modified
– Organisms is expressing genes that did not occur
naturally
– A new gene was inserted into the genome of an
organism
Examples of GMOs
Gene Engineered Plant. Scientists have learned how to insert genes that
code for certain traits and transfer them from one species to another. The
organism that gets the new genes will then have the potential to express the
new traits coded in the newly acquired genes.
Examples of GMOs
Research Animals
Examples of
GMOs
Medicines
Humans make only a
small amount of human
tissue plasminogen
activator (t-PA) naturally.
By genetically modifying
Chinese hamster ovary
(CHO) cells, scientists can
make large amounts of tPA for therapeutic
purposes, such as to clear
blood vessels in the event
of a heart attack or stroke.
Examples of GMOs
• Recombinant
DNA and
genetic
engineering
produces 100’s
of products
Examples of GMO’s
• Almost all produce in grown in the United States
has been genetically modified
Why do you think we
have GMO foods?
• Growing human population
• Loss of farmable land
• Remediation of soil
• Enrich nutrient content
•What are some
desirable traits for
a GMO to have?
• Pest Resistance
• Herbicide Tolerance
• Viral Resistance
• Drought Resistance
Desirable Traits
• Increased Nutritional Value
• Improved Fruit
• Altered Ripening
What are some
Arguments against
GMO’s?
• Creation of super pests
• Creation of super weeds
• Loss of biodiversity
• Biotechnology companies control
agriculture
Opponents
argue
• Health concerns
Types of Genetic Manipulation
• 2. Cloningproducing
identical
organisms
Steps of Cloning
•
•
•
•
Eukaryotes:
1. Copy the genome of the organism to be cloned
2. Impregnate a female with this genome
3. Allow the clone to be born
• Prokaryotes:
• Occurs naturally
• Can use plasmids to create the organism you
want, then allow it to replicate
Who is practicing Biotechnology?
The Biotechnology Workplace

Biotechnology Companies - goal is to produce and sell
commercial “for-profit” products
Staff- scientists, researchers, lab technicians,
manufacturing, marketing, sales

Universities - conduct “pure science” research, nonprofit
Report results in scientific journals or meetings for the
“public good”
The Biotechnology Workplace
• Government Agencies
• CDC Centers for Disease Control and
Prevention-national research center for
developing and applying disease prevention
and control, environmental health, and health
promotion and education activities to improve
public health
• NIH National Institutes of Health- the federal
agency that funds and conducts biomedical
The Biotechnology Workplace
• DNA fingerprinting used by:
– Forensic scientists within police departments to
identify suspects
– Ecologists to determine parentage of endangered
species for breeding purposes
– Wildlife biologists/customs agents to identify
illegally poached or transported animals (bear gall
bladders, rhinoceros horns, ivory from tusks,
exotic birds)
– Evolutionary biologists to determine relatedness of
organisms (red panda is more closely related to
the raccoon than it is to the black and white panda
bear)
Federal agencies governing
product development

Food and Drug Administration (FDA)- regulates the use
and production of food, feed, food additives, veterinary
drugs, human drugs, and medical devices

Environmental Protection Agency (EPA)- enforces
environmental laws including the use and production of
microorganisms, herbicides, pesticides, and genetically
modified microorganisms

United States Department of Agriculture (USDA)regulates the use and production of plants, plant products,
plant tests, veterinary supplies and medications, and
genetically modified plants and animals
The Human Genome Project


Determined the human DNA sequence
Scientists now work on:
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Identifying all of the genes
Determining their functions
Understanding how and when genes are
turned on and off
What can this project do to advance
biotechnology?