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Restriction Enzymes. Enzymes that CUT DNA at a specific nucleotide sequence May produce blunt ends or sticky ends. Sequence cut is a palindrome - same letters forward and backwards! . Blunt End Cuts. Used to isolate a fragment of DNA
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Restriction Enzymes • Enzymes that CUT DNA at a specific nucleotide sequence • May produce bluntends or sticky ends. • Sequence cut is a palindrome - same letters forward and backwards!
Blunt End Cuts • Used to isolate a fragment of DNA • Used to cut DNA into pieces for DNA fingerprinting
Sticky End Cuts • Used when one DNA fragment is combined with another DNA fragment to make RECOMBINANT DNA • Allow complementary base pairs to join together.
Where do Restriction Enzymes come from? • Found in bacteria • Enzymes are used to cut and degrade viruses that enter their cells • Named for species in which R.E. was found • Example: EcoR1 was first R.E. to be isolated from E. coli Picture of the protein molecule Sequence of bases cut by EcoR1
Practical Applications • Gene for human insulin or human growth hormone placed into a bacterial plasmid. • Gene for disease resistance placed into DNA in cells of a corn plant
What’s next? • We will use this information to model the genetic engineering of the hormone, insulin • You will choose the best restriction enzyme to cut out the insulin gene and place it into the bacterial plasmid