SUPERFAMILY 1.75 HMM library and genome assignments server

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DNA polymerase III psi subunit superfamily

SCOP classification
Root:   SCOP hierarchy in SUPERFAMILY [ 0] (11)
Class:   Alpha and beta proteins (a/b) [ 51349] (147)
Fold:   DNA polymerase III psi subunit [ 102219]
Superfamily:   DNA polymerase III psi subunit [ 102220]
Families:   DNA polymerase III psi subunit [ 102221]

Superfamily statistics
Genomes (331) Uniprot 2018_03 genome PDB chains (SCOP 1.75)
Domains 331 1,738 1
Proteins 331 1,738 1

Functional annotation
General category Information
Detailed category DNA replication/repair

Function annotation of SCOP domain superfamilies

InterPro annotation
Cross references IPR004615 SSF102220 Protein matches

DNA-directed DNA polymerase 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 family is 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.

InterPro database

PDBeMotif information about ligands, sequence and structure motifs
Cross references PDB entries
Ligand binding statistics
Nucleic-acid binding statistics
Occurrence of secondary structure elements
Occurrence of small 3D structural motifs

PDBeMotif resource

Jump to [ Top of page · SCOP classification · InterPro annotation · PDBeMotif links · Functional annotation ]

Internal database links

Browse genome assignments for this superfamily. The SUPERFAMILY hidden Markov model library has been used to carry out SCOP domain assignments to all genomes at the superfamily level.

Alignments of sequences to 1 models in this superfamily are available by clicking on the 'Alignments' icon above. PDB sequences less than 40% identical are shown by default, but any other sequence(s) may be aligned. Select PDB sequences, genome sequences, or paste in or upload your own sequences.

Browse and view proteins in genomes which have different domain combinations including a DNA polymerase III psi subunit domain.

Examine the distribution of domain superfamilies, or families, across the major taxonomic kingdoms or genomes within a kingdom. This gives an immediate impression of how superfamilies, or families, are restricted to certain kingdoms of life.

Explore domain occurrence network where nodes represent genomes and edges are domain architectures (shared between genomes) containing the superfamily of interest.

There are 1 hidden Markov models representing the DNA polymerase III psi subunit superfamily. Information on how the models are built, and plots showing hydrophobicity, match emmission probabilities and insertion/deletion probabilities can be inspected.

Jump to [ Top of page · SCOP classification · InterPro annotation · PDBeMotif links · Functional annotation · Internal database links ]