View source for 1gb7


==CRYSTAL STRUCTURE OF MUTANT HUMAN LYSOZYME SUBSTITUTED AT THE SURFACE POSITIONS==
<StructureSection load='1gb7' size='340' side='right'caption='[[1gb7]], [[Resolution|resolution]] 1.80&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1gb7]] 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=1GB7 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1GB7 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=1gb7 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1gb7 OCA], [https://pdbe.org/1gb7 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1gb7 RCSB], [https://www.ebi.ac.uk/pdbsum/1gb7 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1gb7 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/gb/1gb7_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=1gb7 ConSurf].
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== Publication Abstract from PubMed ==
To evaluate the contribution of the amino acid residues on the surface of a protein to its stability, a series of hydrophobic mutant human lysozymes (Val to Gly, Ala, Leu, Ile, Met, and Phe) modified at three different positions on the surface, which are located in the alpha-helix (Val 110), the beta-sheet (Val 2), and the loop (Val 74), were constructed. Their thermodynamic parameters of denaturation and crystal structures were examined by calorimetry and by X-ray crystallography at 100 K, respectively. Differences in the denaturation Gibbs energy change between the wild-type and the hydrophobic mutant proteins ranged from 4.6 to -9.6 kJ/mol, 2.7 to -1.5 kJ/mol, and 3.6 to -0.2 kJ/mol at positions 2, 74, and 110, respectively. The identical substitution at different positions and different substitutions at the same position resulted in different degrees of stabilization. Changes in the stability of the mutant proteins could be evaluated by a unique equation considering the conformational changes due to the substitutions [Funahashi et al. (1999) Protein Eng. 12, 841-850]. For this calculation, secondary structural propensities were newly considered. However, some mutant proteins were not adapted to the equation. The hydration structures around the mutation sites of the exceptional mutant proteins were affected due to the substitutions. The stability changes in the exceptional mutant proteins could be explained by the formation or destruction of the hydration structures. These results suggest that the hydration structure mediated via hydrogen bonds covering the protein surface plays an important role in the conformational stability of the protein.

Role of surface hydrophobic residues in the conformational stability of human lysozyme at three different positions.,Funahashi J, Takano K, Yamagata Y, Yutani K Biochemistry. 2000 Nov 28;39(47):14448-56. PMID:11087397<ref>PMID:11087397</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 1gb7" style="background-color:#fffaf0;"></div>

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