Difference Between Endonuclease And Exonuclease

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Endonucleases are enzymes that cleave nucleic acids at internal sites, while exonucleases are enzymes that cleave nucleic acids at their ends. The main difference between endonuclease and exonuclease is that endonucleases can cleave nucleic acids at any point within the molecule while exonucleases can only cleave nucleic acids from their ends.

What is Endonuclease ?

Endonucleases are enzymes that cleave nucleic acids at specific sites within the molecule. These enzymes are classified according to the type of nucleic acid they act upon, as well as the type of bond they cleave. Endonucleases that act upon DNA are further classified into two groups: those that cleave phosphodiester bonds and those that cleave internucleotide linkages.

Endonucleases play an important role in many cellular processes, including DNA replication, repair, and recombination. In addition, endonucleases are used in molecular biology laboratories to create specific fragments of DNA for use in various experiments.

What is Exonuclease?

Exonucleases are enzymes that catalyze the hydrolysis of nucleotides from the end of a polynucleotide chain. The exonuclease activity can be divided into two types: 3′-exonucleases and 5′-exonucleases. 3′-exonucleases cleave nucleotides from the 3′-end of a polynucleotide chain, while 5′-exonucleases cleave nucleotides from the 5′-end. Exonucleases are important enzymes in DNA metabolism, as they play a role in DNA replication, repair, and recombination.

3′-Exonucleases are involved in DNA replication, as they help to proofread newly synthesized DNA strands for errors.

Main differences between Endonuclease and Exonuclease

Endonucleases are enzymes that cut DNA at a specific point within the molecule, while exonucleases are enzymes that break down DNA from the ends of the molecule. Endonucleases usually recognize a specific sequence of nucleotides, and make cuts within that sequence. Exonucleases work by breaking down nucleotides one at a time from the ends of the DNA strand. Endonucleases are used in many molecular biology techniques, such as PCR (polymerase chain reaction), while exonucleases are used in DNA sequencing.

Similar Frequently Asked Questions (FAQ)

What are the differences between an endonuclease and an exonuclease?

Endonucleases are enzymes that cleave the phosphodiester bond within a nucleotide. They can be further classified into two types, site-specific endonucleases and nonspecific endonucleases. Site-specific endonucleases cleave nucleotides at a specific site, while nonspecific endonucleases cleave nucleotides randomly. Exonucleases are enzymes that cleave the phosphodiester bond from the 3’ or 5’ end of a nucleotide. They can also be classified into two types, 3’ exonucleases and 5’ exonucleases. 3’ exonuclease cleaves nucleotides from the 3’ end, while 5’ exonuclease cleaves nucleotides from the 5’ end.

In conclusion,the main difference between endonuclease and exonuclease is that endonuclease cleaves the phosphodiester bond at the internucleotide level within a polynucleotide chain, while exonuclease cleaves the phosphodiester bond at the externucleotide level. Endonucleases are further classified into type I and type II endonucleases based on their specific cleavage site.