Protein-primed DNA replication

Initiation of replication occurs via a protein primer-dependent mechanism. The protein linked in 5'-genomic DNA is either the polymerase itself (hepadnaviridae), of a terminal protein (TP) (Adenoviridae, Tectiviridae, Salasviridae).

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Enzymatic reaction:
Protein-primed terminal deoxynucleotidyl transferase : DNA-dependent DNA polymerase (DdDp) attaches one or more nucleotides to a Tyrosine or Serine in the target protein through a nucleotidyl-transferase reaction (Nucleotidylylation).

VirusPolymeraseProtein primeraa primernucleotideRef
AdenoviridaePOLTPSerdCTP
TectiviridaePOLTPTyr
SalasviridaePOLTPSerdAMP
HepadnaviridaePPTyr