Which one of the following restriction endonuclease was isolated and reported for the first time?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → Hind II
Restriction endonucleases cut DNA at a specific recognition sequence. They are named by the bacterium they come from. The first letter is from the genus, the next two letters are from the species, and a Roman number shows the order in which the enzymes were isolated from that strain.
(1) Hind II — Correct. It was the first restriction endonuclease whose action depended on a specific DNA sequence. It always cuts at a particular sequence of six base pairs.
(2) Eco RI — Incorrect. It comes from Escherichia coli RY13. It was isolated later.
(3) Bam HI — Incorrect. It comes from Bacillus amyloliquefaciens. It was isolated later.
(4) Hind III — Incorrect. The Roman number III shows that it was isolated after Hind II from the same strain.
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NCERT Extract:
Restriction Enzymes –
