1kls
From Proteopedia
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|PDB= 1kls |SIZE=350|CAPTION= <scene name='initialview01'>1kls</scene> | |PDB= 1kls |SIZE=350|CAPTION= <scene name='initialview01'>1kls</scene> | ||
|SITE= | |SITE= | ||
| - | |LIGAND= <scene name='pdbligand=ZN:ZINC ION'>ZN</scene> | + | |LIGAND= <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene> |
|ACTIVITY= | |ACTIVITY= | ||
|GENE= | |GENE= | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY=[[5znf|5ZNF]], [[1klr|1KLR]] | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1kls FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1kls OCA], [http://www.ebi.ac.uk/pdbsum/1kls PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1kls RCSB]</span> | ||
}} | }} | ||
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==Overview== | ==Overview== | ||
The Zn finger provides a model for studies of protein structure and stability. Its core contains a conserved phenylalanine residue adjoining three architectural elements: a beta-hairpin, an alpha-helix and a tetrahedral Zn(2+)-binding site. Here, we demonstrate that the consensus Phe is not required for high-affinity Zn(2+) binding but contributes to the specification of a precise DNA-binding surface. Substitution of Phe by leucine in a ZFY peptide permits Zn(2+)-dependent folding. Although a native-like structure is retained, structural fluctuations lead to attenuation of selected nuclear Overhauser enhancements and accelerated amide proton exchange. Surprisingly, wild-type Zn affinity is maintained by entropy-enthalpy compensation (EEC): a hidden entropy penalty (TDeltaDeltaS 7kcal/mol) is balanced by enhanced enthalpy of association (DeltaDeltaH -7kcal/mol) at 25 degrees C. Because the variant is less well ordered than the Phe-anchored domain, the net change in entropy is opposite to the apparent change in configurational entropy. By analogy to the thermodynamics of organometallic complexation, we propose that EEC arises from differences in solvent reorganization. Exclusion of Leu among biological sequences suggests an evolutionary constraint on the dynamics of a Zn finger. | The Zn finger provides a model for studies of protein structure and stability. Its core contains a conserved phenylalanine residue adjoining three architectural elements: a beta-hairpin, an alpha-helix and a tetrahedral Zn(2+)-binding site. Here, we demonstrate that the consensus Phe is not required for high-affinity Zn(2+) binding but contributes to the specification of a precise DNA-binding surface. Substitution of Phe by leucine in a ZFY peptide permits Zn(2+)-dependent folding. Although a native-like structure is retained, structural fluctuations lead to attenuation of selected nuclear Overhauser enhancements and accelerated amide proton exchange. Surprisingly, wild-type Zn affinity is maintained by entropy-enthalpy compensation (EEC): a hidden entropy penalty (TDeltaDeltaS 7kcal/mol) is balanced by enhanced enthalpy of association (DeltaDeltaH -7kcal/mol) at 25 degrees C. Because the variant is less well ordered than the Phe-anchored domain, the net change in entropy is opposite to the apparent change in configurational entropy. By analogy to the thermodynamics of organometallic complexation, we propose that EEC arises from differences in solvent reorganization. Exclusion of Leu among biological sequences suggests an evolutionary constraint on the dynamics of a Zn finger. | ||
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| - | ==Disease== | ||
| - | Known disease associated with this structure: Spastic paraplegia 33 OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=610243 610243]] | ||
==About this Structure== | ==About this Structure== | ||
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[[Category: Qian, X.]] | [[Category: Qian, X.]] | ||
[[Category: Weiss, M A.]] | [[Category: Weiss, M A.]] | ||
| - | [[Category: ZN]] | ||
[[Category: zinc finger]] | [[Category: zinc finger]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 21:50:21 2008'' |
Revision as of 18:50, 30 March 2008
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| Ligands: | |||||||
| Related: | 5ZNF, 1KLR
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
NMR Structure of the ZFY-6T[Y10L] Zinc Finger
Overview
The Zn finger provides a model for studies of protein structure and stability. Its core contains a conserved phenylalanine residue adjoining three architectural elements: a beta-hairpin, an alpha-helix and a tetrahedral Zn(2+)-binding site. Here, we demonstrate that the consensus Phe is not required for high-affinity Zn(2+) binding but contributes to the specification of a precise DNA-binding surface. Substitution of Phe by leucine in a ZFY peptide permits Zn(2+)-dependent folding. Although a native-like structure is retained, structural fluctuations lead to attenuation of selected nuclear Overhauser enhancements and accelerated amide proton exchange. Surprisingly, wild-type Zn affinity is maintained by entropy-enthalpy compensation (EEC): a hidden entropy penalty (TDeltaDeltaS 7kcal/mol) is balanced by enhanced enthalpy of association (DeltaDeltaH -7kcal/mol) at 25 degrees C. Because the variant is less well ordered than the Phe-anchored domain, the net change in entropy is opposite to the apparent change in configurational entropy. By analogy to the thermodynamics of organometallic complexation, we propose that EEC arises from differences in solvent reorganization. Exclusion of Leu among biological sequences suggests an evolutionary constraint on the dynamics of a Zn finger.
About this Structure
1KLS is a Single protein structure of sequence from [1]. Full crystallographic information is available from OCA.
Reference
The hidden thermodynamics of a zinc finger., Lachenmann MJ, Ladbury JE, Phillips NB, Narayana N, Qian X, Weiss MA, J Mol Biol. 2002 Mar 1;316(4):969-89. PMID:11884136
Page seeded by OCA on Sun Mar 30 21:50:21 2008
