Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Analysis of leading and lagging strand synthesis by DNA polymerase D from Thermococcus sp. 9°N



Lucia Greenough, Zvi Kelman, Andrew Gardner


All organisms use multiple DNA polymerases to replicate and maintain their genomes. In archaea, members of family B and family D (polD) DNA polymerases were suggested to participate in chromosomal replication. However, recent studies with Thermococcus kodakaraensis show that only polD is essential for cell viability suggesting that it is the replicative polymerase copying the leading and lagging strands. Using novel fluorescent based assays, the heterodimeric polD from the hyperthermophilic archaeon Thermococcus species 9°N was biochemically characterized. The data support a role for polD in both leading and lagging strand synthesis and are distinct from other previously described polD. Consistent with a role in lagging strand synthesis, polD strand displacement activity forms short 5' flap structures that can be subsequently cleaved by flap endonuclease 1 (Fen1) and the resulting nick sealed by DNA ligase to form contiguous lagging strands. The implication of the results for the roles of polD in DNA replication in archaea is discussed.
Journal of Biological Chemistry


archaea, DNA polymerase, DNA replication


Greenough, L. , Kelman, Z. and Gardner, A. (2015), Analysis of leading and lagging strand synthesis by DNA polymerase D from Thermococcus sp. 9°N, Journal of Biological Chemistry, [online], (Accessed February 25, 2024)
Created May 14, 2015, Updated October 12, 2021