View source for 8api

==THE S VARIANT OF HUMAN ALPHA1-ANTITRYPSIN, STRUCTURE AND IMPLICATIONS FOR FUNCTION AND METABOLISM==
<StructureSection load='8api' size='340' side='right' caption='[[8api]], [[Resolution|resolution]] 3.10&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[8api]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. This structure supersedes the now removed PDB entry [http://oca.weizmann.ac.il/oca-bin/send-pdb?obs=1&id=6api 6api]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=8API OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=8API FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=CYS:CYSTEINE'>CYS</scene>, <scene name='pdbligand=MAN:ALPHA-D-MANNOSE'>MAN</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene></td></tr>
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[7api|7api]], [[9api|9api]]</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=8api FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=8api OCA], [http://www.rcsb.org/pdb/explore.do?structureId=8api RCSB], [http://www.ebi.ac.uk/pdbsum/8api PDBsum]</span></td></tr>
</table>
== Disease ==
[[http://www.uniprot.org/uniprot/A1AT_HUMAN A1AT_HUMAN]] Defects in SERPINA1 are the cause of alpha-1-antitrypsin deficiency (A1ATD) [MIM:[http://omim.org/entry/613490 613490]]. A disorder whose most common manifestation is emphysema, which becomes evident by the third to fourth decade. A less common manifestation of the deficiency is liver disease, which occurs in children and adults, and may result in cirrhosis and liver failure. Environmental factors, particularly cigarette smoking, greatly increase the risk of emphysema at an earlier age.<ref>PMID:1905728</ref> <ref>PMID:2390072</ref> <ref>PMID:2227940</ref>  
== Function ==
[[http://www.uniprot.org/uniprot/A1AT_HUMAN A1AT_HUMAN]] Inhibitor of serine proteases. Its primary target is elastase, but it also has a moderate affinity for plasmin and thrombin. Irreversibly inhibits trypsin, chymotrypsin and plasminogen activator. The aberrant form inhibits insulin-induced NO synthesis in platelets, decreases coagulation time and has proteolytic activity against insulin and plasmin.[:]<ref>PMID:1906855</ref> <ref>PMID:1406456</ref>   Short peptide from AAT: reversible chymotrypsin inhibitor. It also inhibits elastase, but not trypsin. Its major physiological function is the protection of the lower respiratory tract against proteolytic destruction by human leukocyte elastase (HLE).[:]<ref>PMID:1906855</ref> <ref>PMID:1406456</ref>  
== 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/ap/8api_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.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/chain_selection.php?pdb_ID=2ata ConSurf].
<div style="clear:both"></div>
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== Publication Abstract from PubMed ==
The S variant of the human alpha 1-antitrypsin with E-264----V, is responsible for a mild alpha 1-antitrypsin deficiency quite common in the European population. S protein specifically cleaved at the susceptible peptide bond was crystallized and its crystal structure determined and refined to 3.1 A resolution. The S variant crystallizes isomorphous to the normal M variant. The difference Fourier electron density map shows the E----V change as outstanding residual density. In addition, small structural changes of the main polypeptide chain radiate from the site of mutation and affect parts far removed from it. By the mutation, internal hydrogen bonds and salt linkages of E-264 to Y-38 and K-487, respectively, are lost. They cause the far-reaching slight distortions and are probably related to the reduced thermal stability of the S mutant. They may also be responsible for slower folding of the polypeptide chain and the clinical symptoms of alpha 1-antitrypsin deficiency. In a theoretical study by molecular dynamics methods simulations of the M and S proteins were made and the results analysed with respect to structural and dynamic properties and compared with the experimental results. There is a significant correlation between experimental and theoretical results in some respects.

The S variant of human alpha 1-antitrypsin, structure and implications for function and metabolism.,Engh R, Lobermann H, Schneider M, Wiegand G, Huber R, Laurell CB Protein Eng. 1989 Mar;2(6):407-15. PMID:2785270<ref>PMID:2785270</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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==See Also==
*[[Alpha-1-antitrypsin|Alpha-1-antitrypsin]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Deisenhofer, J]]
[[Category: Huber, R]]
[[Category: Loebermann, H]]
[[Category: Tokuoka, R]]
[[Category: Proteinase inhibitor]]