1. Restriction Enzyme Analysis of Lambda DNA DNA Fingerprinting of lambda DNA

2. Purpose 1. See the DNA 2. Become familiar with -Restriction enzymes -Electrophoresis -Analysis of DNA bands

3. 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.

4. Lambda Phage infects E.coli. Its DNA is about 49,000 base pairs long

6. Restrictions enzymes are molecular scissors Recognize specific sequence cut DNA make cuts in the DNA Each enzyme recognizes different sequence.

8. 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.

10. DNA Fingerprinting 1 The dark blue lines are DNA fragments trapped in the gel. DNA fingerprinting is some times used to identify microbes.