Homologous Superfamily

DNA polymerase III, psi subunit superfamily (IPR036654)

Short name: DNA_pol_III_psi_sf

Overlapping entries


DNA-directed DNA polymerase (EC: catalyzes DNA-template-directed extension of the 3'-end of an RNA strand by one nucleotide at a time. DNA polymerase III is a complex, multichain enzyme responsible for most of the replicative synthesis in bacteria. The enzyme also has 3' to 5' exonuclease activity. It has a core composed of alpha, epsilon and theta chains, that associate with a tau subunit which allows the core dimerization to form the PolIII' complex. PolIII' associates with the gamma complex (gamma, delta, delta', psi and chi chains) and with the beta chain. This superfamily represents the psi subunit, the small subunit of the DNA polymerase III holoenzyme in Escherichia coli and related species, whose exact function is not known. It appears to have a narrow taxonomic distribution, being restricted to the gammaproteobacteria. Its structure is composed of three layers (alpha/beta/alpha) with parallel beta-sheet of four strands.

GO terms

Biological Process

GO:0006260 DNA replication

Molecular Function

GO:0008408 3'-5' exonuclease activity
GO:0003887 DNA-directed DNA polymerase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.