Restricton Enzyme Digest Flashcards
What is the biological role of restriction enzymes in bacteria?
They defend against foreign DNA by cutting it into dysfunctional pieces.
Why are restriction sites pallindromic?
Restriction enzymes typically recognize symmetry in double stranded DNA.
What does EcoR1 recognize and cut?
Sequence GAATTC, between G and A
What are the essential components of a restriction digest reaction?
DNA, the enzyme, buffer, dH2O
Why is the choice of buffer crucial in a restriction digest?
Each enzyme requires specific conditions (pH, salt) providing optimal conditions.
Whats the purpose of adding SYBR safe to the gel?
Stains the DNA, allowing it to be visualized under UV light.
What does it mean if a plasmid yields two bands after digestion?
The enzyme cut the plasmid at one site if linear, or two sites if the plasmid is circular and supercoiled.
Why is DNA marker loaded into the first lane?
To estimate the size of DNA fragments by comparing them to known fragment sizes.
