2GXA

Crystal structure of papillomavirus E1 hexameric helicase with ssDNA and MgADP

Summary for 2GXA

• Entry DOI: 10.2210/pdb2gxa/pdb
• Descriptor: 5'-D(*TP*TP*TP*TP*TP*TP*TP*TP*TP*TP*TP*TP*T)-3', Replication protein E1, MAGNESIUM ION, ... (6 entities in total)
• Functional Keywords: dna helicase, aaa+, atpase, replication, virus, initiator protein, replication-dna complex, replication/dna
• Biological source: Bovine papillomavirus type 1
• Cellular location: Host nucleus: P03116
• Total number of polymer chains: 14
• Total formula weight: 386349.08

Authors

Enemark, E.J.,Joshua-Tor, L. (deposition date: 2006-05-08, release date: 2006-07-25, Last modification date: 2023-08-30)

Primary citation

Enemark, E.J.,Joshua-Tor, L.
Mechanism of DNA translocation in a replicative hexameric helicase.
Nature, 442:270-275, 2006

PubMed Abstract: The E1 protein of papillomavirus is a hexameric ring helicase belonging to the AAA + family. The mechanism that couples the ATP cycle to DNA translocation has been unclear. Here we present the crystal structure of the E1 hexamer with single-stranded DNA discretely bound within the hexamer channel and nucleotides at the subunit interfaces. This structure demonstrates that only one strand of DNA passes through the hexamer channel and that the DNA-binding hairpins of each subunit form a spiral 'staircase' that sequentially tracks the oligonucleotide backbone. Consecutively grouped ATP, ADP and apo configurations correlate with the height of the hairpin, suggesting a straightforward DNA translocation mechanism. Each subunit sequentially progresses through ATP, ADP and apo states while the associated DNA-binding hairpin travels from the top staircase position to the bottom, escorting one nucleotide of single-stranded DNA through the channel. These events permute sequentially around the ring from one subunit to the next.

PubMed: 16855583
DOI: 10.1038/nature04943

Experimental method

X-RAY DIFFRACTION (3.15 Å)