DNA REPLICATION

Nucleotid & Nucleosid

Nucleosid

*Figure 07.08

*Figure 07.09

*Figure 07.18

Polymerization of the deoxynucleotides during DNA synthesis. The β and γ phosphates of each deoxynuleosid triphosphate are cleaved off to give energy for the polymerization reaction

A single base can be flipped out from the double helix,which could be important in recombination and repair

*Figure 01.11

*Figure 09.23

*DNA polymerase { ΙΙΙ , Ι }

*Nuclease { endonuclease , exonuclease [ 5´,3´ exonuclease]}

*DNA ligase

*Primase

*Accessory proteins : 10 different protein: β clamp → dnaN gene , clamp loader → help the β clamp

*Helicases and helix- desabilizing proteins or single strand DNA binding proteins

*Topoisomerases

*Figure 09.18

ori C

Initiation of replication at E.coli oriC

DNA Repair*Mismatch repair

*Excision repair

*Recombination repair

*SOS repair

Mismatch repair(methyl-directed mismatch repair)