Type ii topoisomerases display all of the following characteristics except

a. they only introduce supercoiling and cannot relax a covalently closed circular dna.

b. they are found in both e. coli and humans.

c. they require atp to alter the linking number of dna.

d. they alter linking number in increments of 2.

e. they transiently cleave both strands of the double helix.

The correct answer is option A. "They only introduce supercoiling and cannot relax a covalently closed circular DNA".

Explanation:

Type II topoisomerases are enzymes that regulate the winding an unwinding of DNA during DNA replication. Basically, these enzymes are the scissor that remove the knots and tangles formed during the replication process. Is false to affirm that type II topoisomerases only introduce supercoiling and cannot relax a covalently closed circular DNA. Bacterial type II DNA topoisomerases  work with the circular DNA of bacterium by changing the linking number of circular DNA by ±2.

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