Structural highlights
Function
[DPO3B_ECOLI] DNA polymerase III is a complex, multichain enzyme responsible for most of the replicative synthesis in bacteria. This DNA polymerase also exhibits 3' to 5' exonuclease activity. The beta chain is required for initiation of replication once it is clamped onto DNA, it slides freely (bidirectional and ATP-independent) along duplex DNA.
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
DNA polymerases attach to the DNA sliding clamp through a common overlapping binding site. We identify a small-molecule compound that binds the protein-binding site in the Escherichia coli beta-clamp and differentially affects the activity of DNA polymerases II, III, and IV. To understand the molecular basis of this discrimination, the cocrystal structure of the chemical inhibitor is solved in complex with beta and is compared with the structures of Pol II, Pol III, and Pol IV peptides bound to beta. The analysis reveals that the small molecule localizes in a region of the clamp to which the DNA polymerases attach in different ways. The results suggest that the small molecule may be useful in the future to probe polymerase function with beta, and that the beta-clamp may represent an antibiotic target.
Structure of a small-molecule inhibitor of a DNA polymerase sliding clamp.,Georgescu RE, Yurieva O, Kim SS, Kuriyan J, Kong XP, O'Donnell M Proc Natl Acad Sci U S A. 2008 Aug 12;105(32):11116-21. Epub 2008 Aug 4. PMID:18678908[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Georgescu RE, Yurieva O, Kim SS, Kuriyan J, Kong XP, O'Donnell M. Structure of a small-molecule inhibitor of a DNA polymerase sliding clamp. Proc Natl Acad Sci U S A. 2008 Aug 12;105(32):11116-21. Epub 2008 Aug 4. PMID:18678908
