2PJR: Helicase Product Complex

Citation:
Abstract
We have determined two different structures of PcrA DNA helicase complexed with the same single strand tailed DNA duplex, providing snapshots of different steps on the catalytic pathway. One of the structures is of a complex with a nonhydrolyzable analog of ATP and is thus a "substrate" complex. The other structure contains a bound sulphate ion that sits in a position equivalent to that occupied by the phosphate ion produced after ATP hydrolysis, thereby mimicking a "product" complex. In both complexes, the protein is monomeric. Large and distinct conformational changes occur on binding DNA and the nucleotide cofactor. Taken together, these structures provide evidence against an "active rolling" model for helicase action but are instead consistent with an "inchworm" mechanism.
PDB ID: 2PJRDownload
MMDB ID: 54058
PDB Deposition Date: 1999/3/12
Updated in MMDB: 2007/10
Experimental Method:
x-ray diffraction
Resolution: 2.9  Å
Source Organism:
synthetic construct
Similar Structures:
Biological Unit for 2PJR: octameric; determined by author
Molecular Components in 2PJR
Label Count Molecule
Proteins (4 molecules)
2
Protein (Helicase Pcra)
Molecule annotation
2
Protein (Helicase Pcra)
Molecule annotation
Nucleotides(3 molecules)
2
DNA (5'-d(*tp*tp*tp*tp*t)-3')
Molecule annotation
1
DNA (5'-d(*gp*c)-3')
Molecule annotation
1
DNA (5'-d(*ap*cp*tp*gp*c)-3')
Molecule annotation
Chemicals (2 molecules)
1
2
* Click molecule labels to explore molecular sequence information.

Citing MMDB
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