1EN7

ENDONUCLEASE VII (ENDOVII) FROM PHAGE T4

1EN7 の概要

• エントリーDOI: 10.2210/pdb1en7/pdb
• 分子名称: RECOMBINATION ENDONUCLEASE VII, ZINC ION, CALCIUM ION, ... (4 entities in total)
• 機能のキーワード: endonuclease, resolvase, holliday junction, dnase, hydrolase
• 由来する生物種: Enterobacteria phage T4
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 36598.61

構造登録者

Raaijmakers, H.,Vix, O.,Toro, I.,Suck, D. (登録日: 1999-02-07, 公開日: 2000-02-07, 最終更新日: 2024-04-03)

主引用文献

Raaijmakers, H.,Vix, O.,Toro, I.,Golz, S.,Kemper, B.,Suck, D.
X-ray structure of T4 endonuclease VII: a DNA junction resolvase with a novel fold and unusual domain-swapped dimer architecture.
EMBO J., 18:1447-1458, 1999

PubMed Abstract: Phage T4 endonuclease VII (Endo VII), the first enzyme shown to resolve Holliday junctions, recognizes a broad spectrum of DNA substrates ranging from branched DNAs to single base mismatches. We have determined the crystal structures of the Ca2+-bound wild-type and the inactive N62D mutant enzymes at 2.4 and 2.1 A, respectively. The Endo VII monomers form an elongated, highly intertwined molecular dimer exhibiting extreme domain swapping. The major dimerization elements are two pairs of antiparallel helices forming a novel 'four-helix cross' motif. The unique monomer fold, almost completely lacking beta-sheet structure and containing a zinc ion tetrahedrally coordinated to four cysteines, does not resemble any of the known junction-resolving enzymes, including the Escherichia coli RuvC and lambda integrase-type recombinases. The S-shaped dimer has two 'binding bays' separated by approximately 25 A which are lined by positively charged residues and contain near their base residues known to be essential for activity. These include Asp40 and Asn62, which function as ligands for the bound calcium ions. A pronounced bipolar charge distribution suggests that branched DNA substrates bind to the positively charged face with the scissile phosphates located near the divalent cations. A model for the complex with a four-way DNA junction is presented.

PubMed: 10075917
DOI: 10.1093/emboj/18.6.1447

実験手法

X-RAY DIFFRACTION (2.4 Å)