1njg
From Proteopedia
Nucleotide-free form of an Isolated E. coli Clamp Loader Gamma Subunit
Structural highlights
FunctionDPO3X_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. Isoform tau: serves as a scaffold to help in the dimerization of the core complex. Isoform gamma: seems to interact with the delta subunit. to transfer the beta subunit on the DNA. Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedSliding clamps are loaded onto DNA by ATP-driven clamp loader complexes. The structure of the E. coli clamp loader in a nucleotide-free state has been determined previously. We now report crystal structures of a truncated form of the isolated gamma-ATPase subunit, gamma(1-243), of the E. coli clamp loader, in nucleotide-free and bound forms. The gamma subunit adopts a defined conformation when empty, in which the nucleotide binding site is blocked. The binding of either ATPgammaS or ADP, which are shown to bind with equal affinity to gamma(1-243), induces a change in the relative orientation of the two domains such that nucleotides can be accommodated. This change would break one of the gamma:gamma interfaces seen in the empty clamp loader complex, and may represent one step in the activation process. Nucleotide-induced conformational changes in an isolated Escherichia coli DNA polymerase III clamp loader subunit.,Podobnik M, Weitze TF, O'Donnell M, Kuriyan J Structure. 2003 Mar;11(3):253-63. PMID:12623013[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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