This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
1m0d
From Proteopedia
| Line 1: | Line 1: | ||
[[Image:1m0d.jpg|left|200px]] | [[Image:1m0d.jpg|left|200px]] | ||
| - | + | <!-- | |
| - | + | The line below this paragraph, containing "STRUCTURE_1m0d", creates the "Structure Box" on the page. | |
| - | + | You may change the PDB parameter (which sets the PDB file loaded into the applet) | |
| - | + | or the SCENE parameter (which sets the initial scene displayed when the page is loaded), | |
| - | + | or leave the SCENE parameter empty for the default display. | |
| - | | | + | --> |
| - | | | + | {{STRUCTURE_1m0d| PDB=1m0d | SCENE= }} |
| - | + | ||
| - | + | ||
| - | }} | + | |
'''Crystal Structure of Bacteriophage T7 Endonuclease I with a Wild-Type Active Site and Bound Manganese Ions''' | '''Crystal Structure of Bacteriophage T7 Endonuclease I with a Wild-Type Active Site and Bound Manganese Ions''' | ||
| Line 23: | Line 20: | ||
==Reference== | ==Reference== | ||
Metal ions bound at the active site of the junction-resolving enzyme T7 endonuclease I., Hadden JM, Declais AC, Phillips SE, Lilley DM, EMBO J. 2002 Jul 1;21(13):3505-15. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/12093751 12093751] | Metal ions bound at the active site of the junction-resolving enzyme T7 endonuclease I., Hadden JM, Declais AC, Phillips SE, Lilley DM, EMBO J. 2002 Jul 1;21(13):3505-15. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/12093751 12093751] | ||
| - | [[Category: Deoxyribonuclease IV (phage-T(4)-induced)]] | ||
[[Category: Enterobacteria phage t7]] | [[Category: Enterobacteria phage t7]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| Line 30: | Line 26: | ||
[[Category: Lilley, D M.]] | [[Category: Lilley, D M.]] | ||
[[Category: Phillips, S E.]] | [[Category: Phillips, S E.]] | ||
| - | [[Category: | + | [[Category: Composite active site]] |
| - | [[Category: | + | [[Category: Domain swapped]] |
| - | [[Category: | + | [[Category: Holliday junction resolvase]] |
| - | [[Category: | + | [[Category: Homodimer]] |
| - | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 00:28:47 2008'' | |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | |
Revision as of 21:28, 2 May 2008
Crystal Structure of Bacteriophage T7 Endonuclease I with a Wild-Type Active Site and Bound Manganese Ions
Overview
T7 endonuclease I is a nuclease that is selective for the structure of the four-way DNA junction. The active site is similar to those of a number of restriction enzymes. We have solved the crystal structure of endonuclease I with a wild-type active site. Diffusion of manganese ions into the crystal revealed two peaks of electron density per active site, defining two metal ion-binding sites. Site 1 is fully occupied, and the manganese ion is coordinated by the carboxylate groups of Asp55 and Glu65, and the main chain carbonyl of Thr66. Site 2 is partially occupied, and the metal ion has a single protein ligand, the remaining carboxylate oxygen atom of Asp55. Isothermal titration calorimetry showed the sequential exothermic binding of two manganese ions in solution, with dissociation constants of 0.58 +/- 0.019 and 14 +/- 1.5 mM. These results are consistent with a two metal ion mechanism for the cleavage reaction, in which the hydrolytic water molecule is contained in the first coordination sphere of the site 1-bound metal ion.
About this Structure
1M0D is a Single protein structure of sequence from Enterobacteria phage t7. Full crystallographic information is available from OCA.
Reference
Metal ions bound at the active site of the junction-resolving enzyme T7 endonuclease I., Hadden JM, Declais AC, Phillips SE, Lilley DM, EMBO J. 2002 Jul 1;21(13):3505-15. PMID:12093751 Page seeded by OCA on Sat May 3 00:28:47 2008
