Advertisements
Advertisements
प्रश्न
How does a restriction nuclease function? Explain
Advertisements
उत्तर
Restriction endonuclease functions by recognising its specific sequence. It binds to the DNA and cuts each to the two strands of the double helix at specific points in their sugar phosphate backbones. These enzymes cut the strand of DNA between the same two bases on the opposite strands leaving a single-stranded portion at their ends. These overhanging stretches are called sticky ends on each strand. The enzyme DNA ligase functions depending on the stickiness of these ends. For example, the restriction endonuclease EcoRI found in the colon bacteria E. coli recognises the base sequence GAATTC in the DNA duplex and cuts its strands between G and A.
APPEARS IN
संबंधित प्रश्न
Mention the difference in the mode of action of exonuclease and endonuclease.
Name and describe the technique that helps in separating the DNA fragments formed by the use of restriction endonuclease
Answer the following question.
Explain the significance of palindromic nucleotide sequence in the formation of recombinant DNA.
Which of the following radioisotope is not suitable for DNA labeling based studies?
Restriction enzymes ______.
Molecular scissors, which cut DNA at specific site is ______.
In agarose gel electrophoresis, DNA molecules are separated on the basis of their ______.
The role of DNA ligase in the construction of a recombinant DNA molecule is ______.
Given below is the restriction site of a restriction endonuclease Pst-I and the cleavage sites on a DNA molecule.
\[\ce{5' C - T - G - C - A \overset{\downarrow}{-}{G 3'}}\]
\[\ce{3' G\underset{\uparrow}{-} A - C - G - T - C 5'}\]
Choose the option that gives the correct resultant fragments by the action of the enzyme Pst-I.
What is the origin of agarose, the matrix most commonly used in gel electrophoresis?
