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1xrz

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Revision as of 21:03, 9 September 2015

NMR Structure of a Zinc Finger with Cyclohexanylalanine Substituted for the Central Aromatic Residue

Structural highlights

1xrz is a 1 chain structure. Full experimental information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:
NonStd Res:
Related:	5znf, 1kls, 1klr
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum

Function

[ZFY_HUMAN] Probable transcriptional activator. Binds to the consensus sequence 5'-AGGCCY-3'.

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

The classical Zn finger contains a phenylalanine at the crux of its three architectural elements: a beta-hairpin, an alpha-helix, and a Zn(2+)-binding site. Surprisingly, phenylalanine is not required for high-affinity Zn2+ binding, but instead contributes to the specification of a precise DNA-binding surface. Substitution of phenylalanine by leucine leads to a floppy but native-like structure whose Zn affinity is maintained by marked entropy-enthalpy compensation (DeltaDeltaH -8.3 kcal/mol and -TDeltaDeltaS 7.7 kcal/mol). Phenylalanine and leucine differ in shape, size, and aromaticity. To distinguish which features correlate with dynamic stability, we have investigated a nonstandard finger containing cyclohexanylalanine at this site. The structure of the nonstandard finger is similar to that of the native domain. The cyclohexanyl ring assumes a chair conformation, and conformational fluctuations characteristic of the leucine variant are damped. Although the nonstandard finger exhibits a lower affinity for Zn2+ than does the native domain (DeltaDeltaG -1.2 kcal/mol), leucine-associated perturbations in enthalpy and entropy are almost completely attenuated (DeltaDeltaH -0.7 kcal/mol and -TDeltaDeltaS -0.5 kcal/mol). Strikingly, global changes in entropy (as inferred from calorimetry) are in each case opposite in sign from changes in configurational entropy (as inferred from NMR). This seeming paradox suggests that enthalpy-entropy compensation is dominated by solvent reorganization rather than nominal molecular properties. Together, these results demonstrate that dynamic and thermodynamic perturbations correlate with formation or repair of a solvated packing defect rather than type of physical interaction (aromatic or aliphatic) within the core.

Solvation and the hidden thermodynamics of a zinc finger probed by nonstandard repair of a protein crevice.,Lachenmann MJ, Ladbury JE, Qian X, Huang K, Singh R, Weiss MA Protein Sci. 2004 Dec;13(12):3115-26. PMID:15557258^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Lachenmann MJ, Ladbury JE, Qian X, Huang K, Singh R, Weiss MA. Solvation and the hidden thermodynamics of a zinc finger probed by nonstandard repair of a protein crevice. Protein Sci. 2004 Dec;13(12):3115-26. PMID:15557258 doi:13/12/3115

1 Structural highlights
2 Function
3 Evolutionary Conservation
4 Publication Abstract from PubMed
5 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1xrz"

@@ Line 6: / Line 6: @@
 <tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=ALC:2-AMINO-3-CYCLOHEXYL-PROPIONIC+ACID'>ALC</scene></td></tr>
 <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[5znf|5znf]], [[1kls|1kls]], [[1klr|1klr]]</td></tr>
-<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1xrz FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1xrz OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1xrz RCSB], [http://www.ebi.ac.uk/pdbsum/1xrz PDBsum]</span></td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1xrz FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1xrz OCA], [http://pdbe.org/1xrz PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1xrz RCSB], [http://www.ebi.ac.uk/pdbsum/1xrz PDBsum]</span></td></tr>
 </table>
 == Function ==
@@ Line 28: / Line 28: @@
 From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
 </div>
+<div class="pdbe-citations 1xrz" style="background-color:#fffaf0;"></div>
 == References ==
 <references/>

1xrz

From Proteopedia

Revision as of 21:03, 9 September 2015

NMR Structure of a Zinc Finger with Cyclohexanylalanine Substituted for the Central Aromatic Residue

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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