Key Enzymes in DNA Replication

helicase

unwinds the DNA helix

rmb = seperating the staircase

single-stranded binding proteins

stabilize single-stranded DNA and prevent the two strands at the replication fork from reforming double-stranded DNA

rmb: these proteins are tryna strand the DNA strands apart since they are forced to be single

topoisomerase

avoids twisting of the DNA by cutting the DNA, turning the DNA on one side of the break in the opposite direction of the twisting force, and rejoining the strands

= this is on TOP of everything to get ready for DNA replication

primase

synthesizes the RNA primer in the 5’-3’ direction to initiate a new DNA strand

rmb = priming the DNA strand by adding RNA

DNA polymerase III

main replication enzyme in e.coli, extends the RNA primer

rmb = third times the charm, so this one is the best at replication

DNA polymerase I

removes the RNA primers on lagging strands to join Okazaki fragments

rmb = no 1 bc it is bullied and used for the annoying work of joining the fragments together

sliding clamp

tethers DNA polymerase III to the DNA template, making replication more efficient

rmb = if ur rock climbing clamps make sure u dont die making it more efficient

DNA ligase

seals the nicks left between adjacent fragments (Okazaki fragments)