Question

What is the enzymatic function of restriction enzymes?

1) to add new nucleotides to the growing strand of DNA
2) to join nucleotides during replication
3) to join nucleotides during transcription
4) to cleave nucleic acids at specific sites
5) to repair breaks in sugar-phosphate backbones

Answer 1

The enzymatic function of restriction enzymes is to cleave DNA at specific sites, which are usually palindromic sequences, allowing for the manipulation of DNA in molecular biology.

Step-by-step explanation:

The enzymatic function of restriction enzymes is to cleave nucleic acids at specific sites. These enzymes recognize specific DNA sequences, typically palindromic sequences, and make cuts at those sites. Some restriction enzymes make straight cuts across both strands, producing blunt ends, while others make staggered cuts, leaving sticky ends that can easily be joined to other pieces of DNA with complementary sequences.

These enzymes are essential tools in molecular biology, particularly in the creation of recombinant DNA molecules, where they are used to cut and splice DNA fragments. They are naturally occurring in bacteria and are a part of bacterial defense mechanisms against viruses like bacteriophages, by cutting the foreign DNA that enters the bacterial cell.