Download - DNA Replication and Synthesis
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DNA Replication and Synthesis
•Complementarity
•”It has not escaped our notice that the specific pairing we have postulated immediately suggests a possible copying mechanism … “
•Mode of DNA Replication
•Conservative
•Semiconservative
•Dispersive
*Overview: DNA replication
*Overview: DNA replication
Origin and DirectionReplication fork
Replicon
DNA Polymerases
•chain elongation in a 5’-to-3’ direction•biological activity?
DNA Polymerase
Exonuclease Activities of
DNA Polymerases
Initiation
*Strands must separate•DnaA•Helicases (DnaB and DnaC)•SSBPs (DnaA)•Topoisomerase (DNA gyrase)
*Primase
*Two strands of a double helix are antiparallel
•Continuous DNA synthesis = leading•Discontinuous DNA synthesis = lagging
Initiation