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प्रश्न
'EcoRI' has played a very significant role in rDNA technology.
- Explain the convention for naming EcoRI.
- Write the recognition site and the cleavage sites of this restriction endonuclease.
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उत्तर
(I) Restriction endonucleases are named as follows:
1st alphabet represents the genus of the organism from which the enzyme is isolated.
2nd and 3rd alphabet represent the species of the organism.
4th alphabet represents the strain.
The Roman number represents the order of isolation or discovery of the enzyme.
EcoRI comes from the Escherichia coli RYB strain.
In EcoRI, 'E' comes from the genus 'Escherichia' and 'co' comes from the species name 'Coli'.
The letter 'R' is derived from the name of the strain RYB.
Roman numbers following the names indicate the order in which the enzymes were isolated from that strain of bacteria.
(II) The recognition sequence where EcoRI cleaves the DNA molecule is G/AATTC. Such sequences have a complementary sequence, CTTAA/G, which is known as a palindromic sequence.
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संबंधित प्रश्न
Why is the enzyme cellulase needed for isolating genetic material from plant cells and not form the animal cells?
Answer the following question.
Explain the significance of palindromic nucleotide sequence in the formation of recombinant DNA.
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How does one visualise DNA on an agarose gel?
A mixture of fragmented DNA was electrophoresed in an agarose gel. After staining the gel with ethidium bromide, no DNA bands were observed. What could be the reason?
Carefully observe the given picture. A mixture of DNA with fragments ranging from 200 base pairs to 2500 base pairs was electrophoresed on agarose gel with the following arrangement.
(a) What result will be obtained on staining with ethidium bromide? Explain with reason.
(b) The above setup was modified and a band with 250 base pairs was obtained at X.
What change(s) were made to the previous design to obtain a band at X? Why did the band appear at position X?
What is elution?
State the importance of elution in this process.
