Polymerase

A polymerase is an enzyme (EC 2.7.7.6/7/19/48/49) that synthesizes long chains of polymers or nucleic acids. DNA polymerase and RNA polymerase are used to assemble DNA and RNA molecules, respectively, by copying a DNA template strand using base-pairing interactions or RNA by half ladder replication. A polymerase is an enzyme (EC 2.7.7.6/7/19/48/49) that synthesizes long chains of polymers or nucleic acids. DNA polymerase and RNA polymerase are used to assemble DNA and RNA molecules, respectively, by copying a DNA template strand using base-pairing interactions or RNA by half ladder replication. A DNA polymerase from the thermophilic bacterium, Thermus aquaticus (Taq) (PDB 1BGX, EC 2.7.7.7) is used in the polymerase chain reaction, an important technique of molecular biology. In general, viral single-subunit RNA polymerases/replicases/reverse transcriptase shares a common origin with DNA polymerase. They have a conserved 'palm' domain. Multi-subunit RNA polymerase forms an unrelated group. Primases have a more complex story: bacterial primases with the Toprim domain are related to topoisomerase and mitochrondrial helicase, while archaea and eukaryotic primases form a unrelated family, possibly related to the polymerase palm. Both families nevertheless associate to the same bunch of helicases.