3BEP

Structure of a sliding clamp on DNA

Summary for 3BEP

• Entry DOI: 10.2210/pdb3bep/pdb
• Related: 2POL
• Descriptor: DNA (5'-D(P*DCP*DCP*DCP*DAP*DTP*DCP*DGP*DTP*DAP*DT)-3'), DNA (5'-D(*DTP*DTP*DTP*DTP*DAP*DTP*DAP*DCP*DGP*DAP*DTP*DGP*DGP*DG)-3'), DNA polymerase III subunit beta, ... (5 entities in total)
• Functional Keywords: beta subunit, sliding clamp, e. coli polymerase iii, dna complex, transferase, transcription-dna complex, transcription/dna
• Biological source: Escherichia coli
• Cellular location: Cytoplasm : P0A988
• Total number of polymer chains: 4
• Total formula weight: 89038.46

Authors

Georgescu, R.E.,Kim, S.S.,Yurieva, O.,Kuriyan, J.,Kong, X.-P.,O'Donnell, M. (deposition date: 2007-11-19, release date: 2008-01-29, Last modification date: 2023-08-30)

Primary citation

Georgescu, R.E.,Kim, S.S.,Yurieva, O.,Kuriyan, J.,Kong, X.-P.,O'Donnell, M.
Structure of a sliding clamp on DNA
Cell(Cambridge,Mass.), 132:43-54, 2008

PubMed Abstract: The structure of the E. coli beta clamp polymerase processivity factor has been solved in complex with primed DNA. Interestingly, the clamp directly binds the DNA duplex and also forms a crystal contact with the ssDNA template strand, which binds into the protein-binding pocket of the clamp. We demonstrate that these clamp-DNA interactions function in clamp loading, perhaps by inducing the ring to close around DNA. Clamp binding to template ssDNA may also serve to hold the clamp at a primed site after loading or during switching of multiple factors on the clamp. Remarkably, the DNA is highly tilted as it passes through the beta ring. The pronounced 22 degrees angle of DNA through beta may enable DNA to switch between multiple factors bound to a single clamp simply by alternating from one protomer of the ring to the other.

PubMed: 18191219
DOI: 10.1016/j.cell.2007.11.045

Experimental method

X-RAY DIFFRACTION (1.92 Å)