2hz8

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Current revision (16:37, 13 December 2023) (edit) (undo)
 
(14 intermediate revisions not shown.)
Line 1: Line 1:
-
[[Image:2hz8.jpg|left|200px]]<br /><applet load="2hz8" size="350" color="white" frame="true" align="right" spinBox="true"
 
-
caption="2hz8" />
 
-
'''QM/MM structure refined from NMR-structure of a single chain diiron protein'''<br />
 
-
==Overview==
+
==QM/MM structure refined from NMR-structure of a single chain diiron protein==
-
The de novo design of di-iron proteins is an important step towards understanding the diversity of function among this complex family of metalloenzymes. Previous designs of due ferro (DF) proteins have resulted in tetrameric and dimeric four-helix bundles having crystallographically well-defined structures and active-site geometries. Here, the design and characterization of DFsc, a 114 residue monomeric four-helix bundle, is presented. The backbone was modeled using previous oligomeric structures and appropriate inter-helical turns. The identities of 26 residues were predetermined, including the primary and secondary ligands in the active site, residues involved in active site accessibility, and the gamma beta gamma beta turn between helices 2 and 3. The remaining 88 amino acid residues were determined using statistical computer aided design, which is based upon a recent statistical theory of protein sequences. Rather than sampling sequences, the theory directly provides the site-specific amino acid probabilities, which are then used to guide sequence design. The resulting sequence (DFsc) expresses well in Escherichia coli and is highly soluble. Sedimentation studies confirm that the protein is monomeric in solution. Circular dichroism spectra are consistent with the helical content of the target structure. The protein is structured in both the apo and the holo forms, with the metal-bound form exhibiting increased stability. DFsc stoichiometrically binds a variety of divalent metal ions, including Zn(II), Co(II), Fe(II), and Mn(II), with micromolar affinities. 15N HSQC NMR spectra of both the apo and Zn(II) proteins reveal excellent dispersion with evidence of a significant structural change upon metal binding. DFsc is then a realization of complete de novo design, where backbone structure, activity, and sequence are specified in the design process.
+
<StructureSection load='2hz8' size='340' side='right'caption='[[2hz8]]' scene=''>
 +
== Structural highlights ==
 +
<table><tr><td colspan='2'>[[2hz8]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2HZ8 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2HZ8 FirstGlance]. <br>
 +
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Solution NMR</td></tr>
 +
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>
 +
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=2hz8 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2hz8 OCA], [https://pdbe.org/2hz8 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2hz8 RCSB], [https://www.ebi.ac.uk/pdbsum/2hz8 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2hz8 ProSAT]</span></td></tr>
 +
</table>
 +
<div style="background-color:#fffaf0;">
 +
== Publication Abstract from PubMed ==
 +
We report the solution NMR structure of a designed dimetal-binding protein, di-Zn(II) DFsc, along with a secondary refinement step employing molecular dynamics techniques. Calculation of the initial NMR structural ensemble by standard methods led to distortions in the metal-ligand geometries at the active site. Unrestrained molecular dynamics using a nonbonded force field for the metal shell, followed by quantum mechanical/molecular mechanical dynamics of DFsc, were used to relax local frustrations at the dimetal site that were apparent in the initial NMR structure and provide a more realistic description of the structure. The MD model is consistent with NMR restraints, and in good agreement with the structural and functional properties expected for DF proteins. This work demonstrates that NMR structures of metalloproteins can be further refined using classical and first-principles molecular dynamics methods in the presence of explicit solvent to provide otherwise unavailable insight into the geometry of the metal center.
-
==About this Structure==
+
Solution NMR structure of a designed metalloprotein and complementary molecular dynamics refinement.,Calhoun JR, Liu W, Spiegel K, Dal Peraro M, Klein ML, Valentine KG, Wand AJ, Degrado WF Structure. 2008 Feb;16(2):210-5. PMID:18275812<ref>PMID:18275812</ref>
-
2HZ8 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with <scene name='pdbligand=ZN:'>ZN</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2HZ8 OCA].
+
-
==Reference==
+
From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
-
Computational design and characterization of a monomeric helical dinuclear metalloprotein., Calhoun JR, Kono H, Lahr S, Wang W, DeGrado WF, Saven JG, J Mol Biol. 2003 Dec 12;334(5):1101-15. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=14643669 14643669]
+
</div>
 +
<div class="pdbe-citations 2hz8" style="background-color:#fffaf0;"></div>
 +
== References ==
 +
<references/>
 +
__TOC__
 +
</StructureSection>
[[Category: Escherichia coli]]
[[Category: Escherichia coli]]
-
[[Category: Protein complex]]
+
[[Category: Large Structures]]
-
[[Category: Calhoun, J R.]]
+
[[Category: Calhoun JR]]
-
[[Category: DeGrado, W F.]]
+
[[Category: Dal Peraro M]]
-
[[Category: Klein, M L.]]
+
[[Category: DeGrado WF]]
-
[[Category: Liu, W.]]
+
[[Category: Klein ML]]
-
[[Category: Peraro, M Dal.]]
+
[[Category: Liu W]]
-
[[Category: Spiegel, K.]]
+
[[Category: Spiegel K]]
-
[[Category: Wand, A J.]]
+
[[Category: Wand AJ]]
-
[[Category: ZN]]
+
-
[[Category: four-helix bundle]]
+
-
 
+
-
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 17:47:27 2008''
+

Current revision

QM/MM structure refined from NMR-structure of a single chain diiron protein

PDB ID 2hz8

Drag the structure with the mouse to rotate

Proteopedia Page Contributors and Editors (what is this?)

OCA

Personal tools