Housekeeping

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Housekeeping

• Exam back today
• Transcription/Translation talks (grades outside
  my office on yellow sheets)
• Homework 3 due May2
• Lab
• Quiz 3 4/30-next week!
• Quiz 4 5/7 (cumulative)

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Saga 2Help the sick cows!!
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What is a fast genetic test to detect a
bacteria from a poop sample?
How can we differentiate between different
bacterial isolates?
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PCR polymerase chain reaction

• Amplification of small portions of DNA
• Amount of amplification
• Makes results visible
• Increase sensitivity
• Specific amplification
• Increase specificity

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Collect cow poop
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PCR (uses hybridization)

• 1. Denature DNA
• Separate double helix
• 2. Anneal
• Primers sit onto DNA
• 3. Elongation
• Amplify DNA piece of interest

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What do you need?
Purpose
Ingredients
Taq polymerase
Add nucleotides to template
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PCR
Fig. 8.24
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PCR
Fig. 8.24
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PCR
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Collect cow poop
Isolate DNA from poop
Amplify specific piece from M. paratuberculosis
with PCR
Verify if that piece is present in the poop!
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Gel electrophoresis
M. paratuberculosis is in these cows poop!
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Other uses of PCR??

• Amplification of DNA/RNA
• Diagnostics (detection of BAD organisms)
• Evolutionary comparisons
• Analysis of Ancient DNA/RNA
• Differentiation between organisms
• Gene expression?
• Identification of mRNA (use modified version of
  PCR)

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Exam data
Average 39.2 (79) Range 26.5 to 50