1FZR

CRYSTAL STRUCTURE OF BACTERIOPHAGE T7 ENDONUCLEASE I

Summary for 1FZR

• Entry DOI: 10.2210/pdb1fzr/pdb
• Descriptor: ENDONUCLEASE I (2 entities in total)
• Functional Keywords: holliday junction resolvase, homodimer, domain swapped, composite active site, hydrolase
• Biological source: Enterobacteria phage T7
• Total number of polymer chains: 4
• Total formula weight: 64278.23

Authors

Hadden, J.M.,Convery, M.A.,Declais, A.C.,Lilley, D.M.J.,Phillips, S.E.V. (deposition date: 2000-10-04, release date: 2001-01-17, Last modification date: 2024-02-07)

Primary citation

Hadden, J.M.,Convery, M.A.,Declais, A.C.,Lilley, D.M.,Phillips, S.E.
Crystal structure of the Holliday junction resolving enzyme T7 endonuclease I.
Nat.Struct.Biol., 8:62-67, 2001

PubMed Abstract: We have solved the crystal structure of the Holliday junction resolving enzyme T7 endonuclease I at 2.1 A resolution using the multiwavelength anomalous dispersion (MAD) technique. Endonuclease I exhibits strong structural specificity for four-way DNA junctions. The structure shows that it forms a symmetric homodimer arranged in two well-separated domains. Each domain, however, is composed of elements from both subunits, and amino acid side chains from both protomers contribute to the active site. While no significant structural similarity could be detected with any other junction resolving enzyme, the active site is similar to that found in several restriction endonucleases. T7 endonuclease I therefore represents the first crystal structure of a junction resolving enzyme that is a member of the nuclease superfamily of enzymes.

PubMed: 11135673
DOI: 10.1038/83067

Experimental method

X-RAY DIFFRACTION (2.1 Å)