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प्रश्न
How does a restriction nuclease function? Explain
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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.
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संबंधित प्रश्न
Name the enzymes that are used for the isolation of DNA from bacterial and fungal cells for recombinant DNA technology.
The total number of nucleotide sequences of DNA that code for a hormone is 1530. The proportion of different bases in the sequence is found to be Adenine = 34%, Guanine = 19%, Cytosine = 23%, Thymine = 19%.
Applying Chargaff’s rule, what conclusion can be drawn?
A mixture containing DNA fragments a, b, c and d, with molecular weights of a + b = c, a > b and d > c was subject to agarose get electrophoresis. This position of these fragments from cathode to anode to anode sides of the gel would be ______.
Molecular scissors, which cut DNA at specific site is ______.
Which of the following enzymes catalyse the removal of nucleotides from the ends of DNA?
Would you choose an exonuclease while producing a recombinant DNA molecule?
What does H in’ ‘d’ and ‘III’ refer to in the enzyme Hind III?
How are DNA fragments visualised once they are separated by gel electrophoresis?
Hind II always cuts DNA molecules at a particular point called recognition sequence and it consists of ______.
Why is it mandatory to cut both the vector DNA and the foreign source DNA with the exact same restriction enzyme when constructing recombinant DNA?
