Eukaryotic chromosome compared to a prokaryotic one.

DNA - Structure

• The structural subunit is a nucleotide.• Each nucleotide is made of a phosphate, a

sugar and a nitrogen base.

DNA Structure

DNA

DNA Replication

This image is from your text. If you can find the error in their illustration of DNA replication, you

have a good understanding of the process.

New nucleotides added to the 3’ end of the new DNA strand.

DNA Replication

• Animation

DNA Replication

• New nucleotides are manufactured during the lag phase of the bacterial growth curve.

Thymine vs. Uracil

Protein Synthesis: transcription

RNA polymerase

Transcription

tRNA structure

20 amino acids

Translation

Operon pg. 225 (pg. 229)

mRNA binds here

Repressible Operon (pg. 225)

Repressible Operon

Binds to Inactive Repressor

Inactive Repressor

Repressible Operon

Inducible Operon (pg. 224)

Inducible Operon

Inducible Operon pg. 224

RNA Codons

Missense

Nonsense Mutation

Base Substitution

Frameshift

Viruses ch. 13

Virus Structure

Protein Capsid

Receptors

Enveloped Virus

Influenza

Hemagglutinin: Receptor Site. Allows attachment to host cell.

Neuraminidase. Enzyme, breaks down mucus, assists virus as it moves in and out of cell.

polyhedralcomplex

helical

enveloped

Lytic Cycle

Lytic Cycle

Viruses ch. 13

Agriculture Transgenics On the Market

Source: USDA

Insect resistant cotton – Bt toxin kills the cotton boll worm• transgene = Bt protein

Insect resistant corn – Bt toxin kills the European corn borer• transgene = Bt protein

Normal Transgenic

Virus resistance - papya resistant to papaya ringspot virus• transgene = virus coat protein

Source: Monsanto

Herbicide resistant crops Now: soybean, corn, canola Coming: sugarbeet, lettuce, strawberry alfalfa, potato, wheat• transgene = modified EPSP synthase or phosphinothricin-N-acetyltransferase

Biotech chymosin; the enzyme used to curdle milk products• transgene = genetically engineered enzyme

bST; bovin somatotropin; used to increasemilk production• transgene = genetically engineered enzyme

Source: Rent Mother Nature

Source: Chr. Hansen

Next Generation of Ag Biotech Products

Source: Minnesota Microscopy Society

Golden Rice – increased Vitamin A content (but not without controversy)transgene = three pathway enzymes

Sunflower – white mold resistancetransgene = oxalate oxidase from wheat

Turfgrass – herbicide resistance; slower growing (= reduced mowing)

Bio Steel – spider silk expressed in goats; used to make soft-body bullet proof vests (Nexia)

Environmental Applications

Bioremediation - cleanup contaminated sites; uses microbes designed to degrade the pollution

Indicator bacteria – contamination can be detected in the environment

Tooth decay – engineered Streptococcus mutans, the bacteria that destroys enamel

Future Health-related Biotech Products

Vaccines – herpes, hepatitis C, AIDS, malaria

Edible VaccinesTransgenic Plants Serving Human Health Needs

• Works like any vaccine • A transgenic plant with a pathogen protein gene is developed• Potato, banana, and tomato are targets• Humans eat the plant • The body produces antibodies against pathogen protein• Humans are “immunized” against the pathogen• Examples:

DiarrheaHepatitis BMeasles

Prions

Prions

Long chain of abnormal prion chains starting to build.

Prions