Prokaryotic DNA Replication - Polymerization

Question 1

Step 1 of leading strand synthesis?

Answer 1

DnaG protein synthesises the primer.

Question 2

Step 2 of leading strand synthesis?

Answer 2

DNA Polymerase III extends the strand from the primer and proofreads with its 3’ to 5’ exonuclease activity of epsilon and theta subunits while DnaB protein unwinds DNA.

Question 3

Step 1 - lagging strand synthesis?

Answer 3

DnaG lays down a short primer while DnaB unwinds the protein.

Question 4

Step 2 - lagging strand synthesis?

Answer 4

The gamma subunit of DNA Pol III loads a new sliding clamp or beta subunit of DNA Pol III onto the primer.

Question 5

Step 3 - lagging strand synthesis

Answer 5

DNA Polymerase III extends from primer to make an Okazaki fragment.

Question 6

Step 4 - lagging strand

Answer 6

The core component of DNA Polymerase dissociates from the old clamp and associates with a new one until a series of discontinuous RNA-DNA fragments have been made.

Question 7

Step 5 - lagging strand synthesis

Answer 7

DNA Polymerase I removes the primers then fills the gap and DNA ligase joins Okazaki fragments together by joining the sugar backbones with a phosphodiester bond.