Question

Following statements describes the characteristics of the enzyme Restriction Endonucleases. Identify the incorrect statement.
A.The enzymes cut DNA molecules at an identified position within the DNA.
B.The enzyme binds DNA at specific sites and cuts only one of the two strands.
C.The enzyme cuts the sugar-phosphate backbone at specific sites on each strand.
D.The enzyme recognizes a specific palindromic nucleotide sequence in the DONATION.

Answer 1

The endonucleases are the enzymes that cleave the phosphodiester bond within a polynucleotide chain. Some of them have no regard to sequence when cutting the DNA, but many others do so only at specific nucleotide sequences.
The latter group is often called the restriction endonucleases or the restriction enzymes.

Complete answer:
The restriction enzyme cuts the DNA molecules at a particular point by recognizing a specific sequence.
Each of the restriction endonuclease functions by inspecting the length of a DNA sequence.
If it finds its correct recognition sequence, it will be bound to the DNA and cut each of the two strands of the double helix at the specific points in their sugar-phosphate backbone.
Therefore, the correct answer is option B.

Additional information:
The restriction enzymes are also known as the restriction endonuclease. It is the protein produced by the bacteria that cleaves DNA at the specific sites along with the molecule.
In the bacterial cell, the restriction enzymes cleave the foreign DNA, hence, it eliminates the infecting organisms.
The restriction enzymes can also be isolated from the bacterial cells and can be used in the laboratory to manipulate fragments of DNA, such as those that contain genes; for this reason, they are the indispensable tools of the recombinant DNA technology.

Note: The restriction endonucleases are the bacterial enzymes that cleave double-stranded DNA.
The type I Restriction Enzymes are important in the bacterial function but do not cleave DNA at specific sequences.
The type II are described for use in this manual, require highly specific sites for the DNA cleavage, and hence are extremely useful tools in molecular biology.
These enzymes allow the cloning and the purification of defined DNA fragments.