1. Restriction Enzymes Micah Matthews and Hannah Perryman

2. What is the role of a restriction enzyme? To cut DNA molecules at very precise sequences of 4 to 8 base pairs called recognition sites Named according to bacterial species from which they were first isolated Allows genetic engineers to isolate, sequence, and manipulate individual genes derived from any type of organism

3. Sticky End Restriction Enzymes The restriction enzyme scans the DNA for a specific sequence of base pairs, known as the recognition site. The cut results in a DNA fragment with two overhanging sticky ends, ends with exposed nucleotide bases.

4. A Visual of Sticky End Restriction Enzymes http://www.dnalc.org/resources/animations/restriction.html

5. Blunt End Restriction Enzymes The restriction enzyme scans the DNA for a specific sequence of base pairs, known as the recognition site. The cut results in a DNA fragment with two blunt ends, ends with NO exposed nucleotide bases.

6. Visual of Blunt End Restriction Enzymes

7. How is this used? More than 400 restriction enzymes have been isolated from bacteria (see packet for examples). In live bacteria, restriction enzymes defend the cell against invading bacteriophages

8. Sources http://www.mhhe.com/biosci/esp/2001_gbio/fold er_structure/ge/m6/s1/assets/images/gem6s1_1.jpg http://www.mhhe.com/biosci/esp/2001_gbio/fold er_structure/ge/m6/s1/assets/images/gem6s1_1.jpg http://www.uic.edu/classes/phar/phar331/lecture 5/image15.gif http://www.uic.edu/classes/phar/phar331/lecture 5/image15.gif