1zns
From Proteopedia
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| - | [[Image:1zns.gif|left|200px]] | + | [[Image:1zns.gif|left|200px]] |
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| - | '''Crystal structure of N-ColE7/12-bp DNA/Zn complex''' | + | {{Structure |
| + | |PDB= 1zns |SIZE=350|CAPTION= <scene name='initialview01'>1zns</scene>, resolution 2.50Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=ZN:ZINC ION'>ZN</scene> | ||
| + | |ACTIVITY= | ||
| + | |GENE= cea7 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 Escherichia coli]) | ||
| + | }} | ||
| + | |||
| + | '''Crystal structure of N-ColE7/12-bp DNA/Zn complex''' | ||
| + | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 1ZNS is a [ | + | 1ZNS is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1ZNS OCA]. |
==Reference== | ==Reference== | ||
| - | Crystal structural analysis and metal-dependent stability and activity studies of the ColE7 endonuclease domain in complex with DNA/Zn2+ or inhibitor/Ni2+., Doudeva LG, Huang H, Hsia KC, Shi Z, Li CL, Shen Y, Cheng YS, Yuan HS, Protein Sci. 2006 Feb;15(2):269-80. PMID:[http:// | + | Crystal structural analysis and metal-dependent stability and activity studies of the ColE7 endonuclease domain in complex with DNA/Zn2+ or inhibitor/Ni2+., Doudeva LG, Huang H, Hsia KC, Shi Z, Li CL, Shen Y, Cheng YS, Yuan HS, Protein Sci. 2006 Feb;15(2):269-80. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/16434744 16434744] |
[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
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[[Category: protein-dna complex]] | [[Category: protein-dna complex]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 15:37:48 2008'' |
Revision as of 13:37, 20 March 2008
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| , resolution 2.50Å | |||||||
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| Ligands: | |||||||
| Gene: | cea7 (Escherichia coli) | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Crystal structure of N-ColE7/12-bp DNA/Zn complex
Overview
The nuclease domain of ColE7 (N-ColE7) contains an H-N-H motif that folds in a beta beta alpha-metal topology. Here we report the crystal structures of a Zn2+-bound N-ColE7 (H545E mutant) in complex with a 12-bp duplex DNA and a Ni2+-bound N-ColE7 in complex with the inhibitor Im7 at a resolution of 2.5 A and 2.0 A, respectively. Metal-dependent cleavage assays showed that N-ColE7 cleaves double-stranded DNA with a single metal ion cofactor, Ni2+, Mg2+, Mn2+, and Zn2+. ColE7 purified from Escherichia coli contains an endogenous zinc ion that was not replaced by Mg2+ at concentrations of <25 mM, indicating that zinc is the physiologically relevant metal ion in N-ColE7 in host E. coli. In the crystal structure of N-ColE7/DNA complex, the zinc ion is directly coordinated to three histidines and the DNA scissile phosphate in a tetrahedral geometry. In contrast, Ni2+ is bound in N-ColE7 in two different modes, to four ligands (three histidines and one phosphate ion), or to five ligands with an additional water molecule. These data suggest that the divalent metal ion in the His-metal finger motif can be coordinated to six ligands, such as Mg2+ in I-PpoI, Serratia nuclease and Vvn, five ligands or four ligands, such as Ni2+ or Zn2+ in ColE7. Universally, the metal ion in the His-metal finger motif is bound to the DNA scissile phosphate and serves three roles during hydrolysis: polarization of the P-O bond for nucleophilic attack, stabilization of the phosphoanion transition state and stabilization of the cleaved product.
About this Structure
1ZNS is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Crystal structural analysis and metal-dependent stability and activity studies of the ColE7 endonuclease domain in complex with DNA/Zn2+ or inhibitor/Ni2+., Doudeva LG, Huang H, Hsia KC, Shi Z, Li CL, Shen Y, Cheng YS, Yuan HS, Protein Sci. 2006 Feb;15(2):269-80. PMID:16434744
Page seeded by OCA on Thu Mar 20 15:37:48 2008
Categories: Escherichia coli | Single protein | Doudeva, L G. | Hsia, K C. | Huang, H. | Li, C L. | Shen, Y. | Shi, Z. | Yuan, H S. | ZN | Colicin | Endonuclease | H-n-h motif | His-metal finger | Protein-dna complex
