DNA replication

DNA Helicase

Using Atp, unwinds/unzips the H Bonds between base pairs to create the replication fork

Topoisomerase

An enzyme that unwinds/relaxes the DNA. Is infront of the Helicase

Single stranded binding proteins

Keeps the fork open so it doesn’t snap back together. Is on the separated strands.

RNA Primase

Lay down temporary starting point RNA primer. Runs 5’ to 3’.

DNA Polymerase III

Recognize 3’ end of the primer and begins adding DNA nucleotides in a 5’ to 3’ direction. It creates a new strand, one nucleotide at a time. 

Nucleoside Triphosphates

Nucleotides, energy for replication

Leading strand

copied continuously toward replication fork, not always the top

Lagging strand

keeps adding to the 3’ prime side and has to go back to add

DNA Ligase

Hold together DNA strands, form covalent bonds in phosphate sugar back bone, connect okazaki fragments

DNA Polymerase I

Add free floating nucleotides, removes RNA primers

Exonucleases

Remove Nucleotides from the end of DNA strands, 5’ or 3’ ends