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
Explain with the help of a suitable example the naming of a restriction endonuclease.
Mention the difference in the mode of action of exonuclease and endonuclease.
How does restriction endonuclease function?
Explain the roles of the following with the help of an example each in recombinant DNA technology :
Restriction Enzymes
'Restriction' in restriction enzyme refers to
While isolating DNA from bacteria, which of the following enzymes is not required?
Restriction enzymes should not have more than one site of action in the cloning site of a vector. Comment.
Restriction enzymes that are used in the construction of recombinant DNA are endonucleases which cut the DNA at ‘specific-recognition sequence’. What would be the disadvantage if they do not cut the DNA at specific-recognition sequence?
Given below is the stepwise schematic representation of the process of electrophoresis. Identify the 'alphabets' representing
- Anode end
- smallest/lightest DNA strand in the matrix
- Agarose gel
What is the process called when desired, separated DNA bands are physically cut out from the agarose gel and extracted from the gel piece?
