2hnh
From Proteopedia
Crystal structure of the catalytic alpha subunit of E. coli replicative DNA polymerase III
Overview
Bacterial replicative DNA polymerases such as Polymerase III (Pol III) share no sequence similarity with other polymerases. The crystal structure, determined at 2.3 A resolution, of a large fragment of Pol III (residues 1-917), reveals a unique chain fold with localized similarity in the catalytic domain to DNA polymerase beta and related nucleotidyltransferases. The structure of Pol III is strikingly different from those of members of the canonical DNA polymerase families, which include eukaryotic replicative polymerases, suggesting that the DNA replication machinery in bacteria arose independently. A structural element near the active site in Pol III that is not present in nucleotidyltransferases but which resembles an element at the active sites of some canonical DNA polymerases suggests that, at a more distant level, all DNA polymerases may share a common ancestor. The structure also suggests a model for interaction of Pol III with the sliding clamp and DNA.
About this Structure
2HNH is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Crystal structure of the catalytic alpha subunit of E. coli replicative DNA polymerase III., Lamers MH, Georgescu RE, Lee SG, O'Donnell M, Kuriyan J, Cell. 2006 Sep 8;126(5):881-92. PMID:16959568 Page seeded by OCA on Sun May 4 06:29:22 2008
