Transcript Lab Restriction Enzyme Analysis

Restriction Enzyme Analysis of
Lambda DNA
DNA Fingerprinting of lambda
DNA
Purpose
• 1. See the DNA
• 2. Become familiar with
-Restriction enzymes
-Electrophoresis
-Analysis of DNA bands
Applications of the procedure
• Used to identify bacteria and viruses
based on the DNA finger printing of these
organisms.
• Genetic screening – electrophoresis is the
first step.
• Forensic medicine – electrophoresis is
used in DNA finger printing.
• Lambda Phage infects E.coli.
• Its DNA is about 49,000 base pairs long
• Restrictions enzymes are molecular
scissors
• Recognize specific sequence cut DNA
make cuts in the DNA
• Each enzyme recognizes different
sequence.
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Gel is porous
DNA fragments migrate through the gel
Electric current push the DNA
DNA is negatively charged because of the
phosphates
• Migrate from negative to positive
• Smaller fragments migrate faster
• Each band has many copies of a fragment.
DNA Fingerprinting
1
The dark blue lines are DNA fragments trapped in the gel. DNA fingerprinting
is some times used to identify microbes.