1.

Explain the action of the restriction endonuclease EcoRI.

Answer»

i. The recognition sequence shows palindrome character in which the sequence of base pairs read the same on both the DNA strands, i.e., same in 5′ → 3′ or 3′ → 5′ directions, e.g.,

5′ — G A A T T C — 3′

3′ — C T T A A G — 5′

ii. The restriction endonuclease acts on specified length of a DNA and binds to the DNA at the recognition sequence.

iii. It cuts the opposite double helix of DNA in the sugar-phosphate backbones, at little away from the centre of the palindrome sites.

iv. There are overhanging stretches called sticky ends on each strand, which form hydrogen bonds with their complementary cut counterparts. This stickiness of the ends facilitates the action of the enzyme DNA ligase.



Discussion

No Comment Found

Related InterviewSolutions