View source for 1gf4


==BURIED POLAR MUTANT HUMAN LYSOZYME==
<StructureSection load='1gf4' size='340' side='right'caption='[[1gf4]], [[Resolution|resolution]] 1.80&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1gf4]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1GF4 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1GF4 FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.8&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=NA:SODIUM+ION'>NA</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=1gf4 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1gf4 OCA], [https://pdbe.org/1gf4 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1gf4 RCSB], [https://www.ebi.ac.uk/pdbsum/1gf4 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1gf4 ProSAT]</span></td></tr>
</table>
== Disease ==
[https://www.uniprot.org/uniprot/LYSC_HUMAN LYSC_HUMAN] Defects in LYZ are a cause of amyloidosis type 8 (AMYL8) [MIM:[https://omim.org/entry/105200 105200]; also known as systemic non-neuropathic amyloidosis or Ostertag-type amyloidosis. AMYL8 is a hereditary generalized amyloidosis due to deposition of apolipoprotein A1, fibrinogen and lysozyme amyloids. Viscera are particularly affected. There is no involvement of the nervous system. Clinical features include renal amyloidosis resulting in nephrotic syndrome, arterial hypertension, hepatosplenomegaly, cholestasis, petechial skin rash.<ref>PMID:8464497</ref> 
== Function ==
[https://www.uniprot.org/uniprot/LYSC_HUMAN LYSC_HUMAN] Lysozymes have primarily a bacteriolytic function; those in tissues and body fluids are associated with the monocyte-macrophage system and enhance the activity of immunoagents.
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
Check<jmol>
  <jmolCheckbox>
    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/gf/1gf4_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview03.spt</scriptWhenUnchecked>
    <text>to colour the structure by Evolutionary Conservation</text>
  </jmolCheckbox>
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1gf4 ConSurf].
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== Publication Abstract from PubMed ==
It has been generally believed that polar residues are usually located on the surface of protein structures. However, there are many polar groups in the interior of the structures in reality. To evaluate the contribution of such buried polar groups to the conformational stability of a protein, nonpolar to polar mutations (L8T, A9S, A32S, I56T, I59T, I59S, A92S, V93T, A96S, V99T, and V100T) in the interior of a human lysozyme were examined. The thermodynamic parameters for denaturation were determined using a differential scanning calorimeter, and the crystal structures were analyzed by X-ray crystallography. If a polar group had a heavy energy cost to be buried, a mutant protein would be remarkably destabilized. However, the stability (Delta G) of the Ala to Ser and Val to Thr mutant human lysozymes was comparable to that of the wild-type protein, suggesting a low-energy penalty of buried polar groups. The structural analysis showed that all polar side chains introduced in the mutant proteins were able to find their hydrogen bond partners, which are ubiquitous in protein structures. The empirical structure-based calculation of stability change (Delta Delta G) [Takano et al. (1999) Biochemistry 38, 12698--12708] revealed that the mutant proteins decreased the hydrophobic effect contributing to the stability (Delta G(HP)), but this destabilization was recovered by the hydrogen bonds newly introduced. The present study shows the favorable contribution of polar groups with hydrogen bonds in the interior of protein molecules to the conformational stability.

Contribution of polar groups in the interior of a protein to the conformational stability.,Takano K, Yamagata Y, Yutani K Biochemistry. 2001 Apr 17;40(15):4853-8. PMID:11294653<ref>PMID:11294653</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 1gf4" style="background-color:#fffaf0;"></div>

==See Also==
*[[Lysozyme 3D structures|Lysozyme 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Takano K]]
[[Category: Yamagata Y]]
[[Category: Yutani K]]