Explain the role of enzymes in the process of DNA replication in prokaryotes

A variety of enzymes are involved in the process of DNA replication. For replication to occur each strand of DNA must be separated from the other, a result of its double helix structure and the hydrogen bonds between complementary nitrogenous bases. The enzyme, DNA Helicase breaks the hydrogen bonds between the bases from the 5’ to 3’ direction, uncoiling the DNA and separating the strands. Thus, allowing other enzymes involved in the process to access each strand of DNA. Single strand binding proteins bind to each strand to ensure that the strands do not recoil and bind back together. The replication process then splits into two different processes occurring on the leading and lagging strands of DNA. A result of replication occurring in the 5’ to 3’ direction.On the leading strand RNA primase synthesises a short RNA primer that allows DNA polymerase III to bind to and begin adding DNA nucleotides in a 5’ to 3’ direction. Once this is finished, DNA ligase replaces this primer with DNA nucleotides. On the lagging strand, RNA primase places a few primers along the length of the strand. This allows DNA polymerase I to bind to these primers and add a few DNA nucleotides in the 5’ to 3’ direction. These short sequences of nucleotides are known as Okazaki fragments. The short gaps between the fragments are plugged up with nucleotides by DNA ligase and the primers are replaced with DNA nucleotides, forming a continuous strand. 

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