Biochem 2B03 Lec 7
- There are 2 replication box come out from oriC.
- DNA synthesis using stDNA as a template. Becuz of antiparallel duplex,
Leading strand read from 3’5’.
- Lagging = semi-discontinuous . Okazaki = ~100bp in length. Both strands
move in - same direction but in a different fashion.
- 3’ OH group is attached to the alpha phosphate on the deoxy-NTP. .. gamma-
beta-- alpha (Attached to 3’OH on the upper sugar) phosphate
- pyrophosphatase : used to label any enzymes that can remove any kind of
phosphate. Special to hydrolyze the pyrophosphate at the phosphodiester
- E.coli DNA polymerase
o 3 common : Pol 1, Pol II and Pol III (remember only Pol 1 and Pol 3)
o Pol 1: DNA repair, DNA synthesis start from making RNA as a primer.
The primer needs to be removed at the end of replication, pol 1
removes it and also fill in the DNA nucleotides into the gap.
o (study table 28.1, not the mass and molecular weight)
o Pol 3: remember what is the function of proteins. T 28.2, the first 2
form a complex nicely.. theta make sure the 2 above binds and
o Any DNA polymerase has a tendency to make mistake, 3’ exonuclease
removes it and put back the correct bp.
o Beta Sliding clamp: permanent association with DNA. These donut go
through the single stranded DNA. Like a body guard to protect people.
Try to get polymerase to stay on and continue it’s job.
o Tao unit is the linker to bring the two polymerase together.
o Memorize the whole Table 28.2