© 2010 Bioscience Explorations Genetically Modified Organisms Organisms that are modified by the alteration or introduction of foreign DNA, in order to

© 2010 Bioscience Explorations

Genetically Modified Organisms

• Organisms that are modified by the alteration or introduction of foreign DNA, in order to produce a desired trait or effect

• Plants are the most common targets (transgenic crops):– Pest resistance (e.g. Bt-hybrid corn)– Drought resistance– Cold-tolerance– Shelf-life– Ripening– Nutritional value Bt-hybrid vs. non-Bt-

hybrid corn


Creation of a GMO

• Genetic material is artificially combined, usually in the form of circular pieces of DNA called plasmids– Plasmids contain not only DNA coding for

the trait of interest, but also DNA that controls the expression and selection of the trait

• Delivery methods:– Agrobacterium tumefaciens– Ballistics or gene gun– Electroporation– Chemical and/or heat treatment

http://sustain.no/virtue/newsletter/00_08/curr-trant/more-info/plasmid.jpg


• Process by which genetic material carried by an individual cell is altered by the addition and expression of foreign DNA

– The DNA may or may not be incorporated into the genome

• Electrical, thermal, mechanical and chemical and biological methods

• Transformed cells are identified by some type of marker or trait– Antibiotic resistance

– Color

Transformation


Transformation using Agrobacterium tumefaciens

• Bacterial species

• Normally infects plants and causes crown-gall disease

• Very efficient at inserting DNA into plant cell genome – Bingo!


• T-DNA leads to synthesis of:– Auxin – plant hormone causes cell proliferation

– Opines – serve as a source of energy for A. tumefaciens

Symbiotic Relationship




Step 1. Engineer Agrobacterium with your favorite gene(s)….

Ti = Tumor inducing

Step 2. Disarm the genes that cause crown gall disease








Human impact on ecosystems


Kingston fossil plant Ash spill (2008)



Carbon cycle


The instability of a fossil fuel economy


Novel innovations for alternative energy

Wind energy Solar energyCellulosic ethanol

Electric carsHydrogen fuel

cells


Group activity:Rank the following alternative energy technologies from most promising (best) to least promising (worst)

• Biodiesel

• Hydrogen fuel cells

• Electric cars (Lithium ion batteries)

• Cellulosic ethanol

• Wind

• Geothermal

• Solar


One problem with electric cars

Lithium is also a finite resource that is mined from salt flats

Nissan LeafChevy Volt Lithium ion battery


Lithium salt mining in Bolivia


>50% (estimated) of the world’s lithium lies in Salar de Uyuni

Evo Morales: President of

Bolivia


Ethanol as a renewable fuel?

MTBE


Government support for more E85 pumps (85% ethanol, 15% gasoline) • Government announced

Friday 10,000 more E85 pumps in the next 5 years

• "Flex-fuel pumps will give Americans a choice to purchase domestically produced renewable transportation fuels.“- US Agriculture secretary Tom Vilsack (Friday, April 8, 2011)


Overview of Brazil sugarcane ethanol

• ~8 million hectares• Supplies 40% of

Brazil transportation fuel

• Brazil wants to expand to 40

million hectares• Currently only the

sugar part of cane is used (14% of

mass)• Brazil will likely become an ethanol

powerhouse

1 hectare = 2.47 acres


Plants are mostly made up of sugars


Why Cellulosic Ethanol?




Why Switchgrass?• Native grass to

US• Perennial crop

• Requires little to no fertilizer

• Can be grown on marginal land• Use hay bail

machinery• Farmer income

• No erosion• Large fleet of E85 vehicles on

road• Pilot biorefinery

in Vonore, TN

http://www.wbir.com/news/local/story.aspx?storyid=112598


Miscanthus giganteus stand growing for 10 years never fertilized or irrigated


Ethanol: The bad news

• Food vs. fuel vs. feed agricultural land• Absorbs water – 2006- present many complaints

about engine damage with E10 (found to exceed)• EtOH requires 42X more water than gasoline• Energy density is 2/3 that of gasoline• Logistics of moving large amounts of biomass• Calculations of cost-benefit are VERY

complicated– However, technology is so IMMATURE that these

numbers are meaningless


Algae as a renewable source of ethanol and biodiesel


Algae for ethanol and biodiesel: infrastructure costs too great


Survival of the human species depends on our ability to capture energy in a way that is sustainable


We should start planting fields of switchgrass everywhere so we can fuel our cars on renewable fuel

• Without talking to your neighbor, do you agree or disagree?

• Write all of your reasons for your position (one per sticky note) No talking!


It is BETTER for the U.S. government to invest more money into DEFENSE than into ENERGY

• Without talking to your neighbor, do you agree or disagree?

• Write all of your reasons for your position (one per sticky note) No talking!

Documents

© 2010 Bioscience Explorations Genetically Modified Organisms Organisms that are modified by the alteration or introduction of foreign DNA, in order to