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2xkl
From Proteopedia
(Difference between revisions)
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| - | + | ==CRYSTAL STRUCTURE OF MOUSE APOLIPOPROTEIN M== | |
| - | === | + | <StructureSection load='2xkl' size='340' side='right' caption='[[2xkl]], [[Resolution|resolution]] 2.50Å' scene=''> |
| - | + | == Structural highlights == | |
| + | <table><tr><td colspan='2'>[[2xkl]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Mus_musculus Mus musculus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2XKL OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2XKL FirstGlance]. <br> | ||
| + | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=EDO:1,2-ETHANEDIOL'>EDO</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</scene>, <scene name='pdbligand=POL:N-PROPANOL'>POL</scene></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=2xkl FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2xkl OCA], [http://www.rcsb.org/pdb/explore.do?structureId=2xkl RCSB], [http://www.ebi.ac.uk/pdbsum/2xkl PDBsum]</span></td></tr> | ||
| + | </table> | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
| + | Mouse apolipoprotein M (m-apoM) displays a 79% sequence identity to human apolipoprotein M (h-apoM). Both proteins are apolipoproteins associated with high-density lipoproteins, with similar anticipated biological functions. The structure of h-apoM has recently been determined by X-ray crystallography, which revealed that h-apoM displays, as expected, a lipocalin-like fold characterized by an eight-stranded betabarrel that encloses an internal fatty-acid-binding site. Surprisingly, this is not true for m-apoM. After refolding from inclusion bodies, the crystal structure of m-apoM (reported here at 2.5 A resolution) displays a novel yet unprecedented seven-stranded beta-barrel structure. The fold difference is not caused by a mere deletion of a single beta-strand; instead, beta-strands E and F are removed and replaced by a single beta-strand A' formed from residues from the N-terminus. Molecular dynamics simulations suggest that m-apoM is able to adopt both a seven-stranded barrel structure and an eight-stranded barrel structure in solution, and that both folds are comparably stable. Thermal unfolding simulations identify the position where beta-strand exchange occurs as the weak point of the beta-barrel. We wonder whether the switch in topology could have a biological function and could facilitate ligand release, since it goes hand in hand with a narrowing of the barrel diameter. Possibly also, the observed conformation represents an on-pathway or off-pathway folding intermediate of apoM. The difference in fold topology is quite remarkable, and the fold promiscuity observed for m-apoM might possibly provide a glimpse at potential cross-points during the evolution of beta-barrels. | ||
| - | + | Mouse ApoM displays an unprecedented seven-stranded lipocalin fold: folding decoy or alternative native fold?,Sevvana M, Kassler K, Ahnstrom J, Weiler S, Dahlback B, Sticht H, Muller YA J Mol Biol. 2010 Dec 3;404(3):363-71. Epub 2010 Oct 7. PMID:20932978<ref>PMID:20932978</ref> | |
| - | + | ||
| - | == | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> |
| - | < | + | </div> |
| + | == References == | ||
| + | <references/> | ||
| + | __TOC__ | ||
| + | </StructureSection> | ||
[[Category: Mus musculus]] | [[Category: Mus musculus]] | ||
| - | [[Category: Dahlback, B | + | [[Category: Dahlback, B]] |
| - | [[Category: Josefin, A | + | [[Category: Josefin, A]] |
| - | [[Category: Kassler, K | + | [[Category: Kassler, K]] |
| - | [[Category: Muller, Y A | + | [[Category: Muller, Y A]] |
| - | [[Category: Sevvana, M | + | [[Category: Sevvana, M]] |
| - | [[Category: Sticht, H | + | [[Category: Sticht, H]] |
| - | [[Category: Weiler, S | + | [[Category: Weiler, S]] |
[[Category: Lipid transport]] | [[Category: Lipid transport]] | ||
Revision as of 14:07, 17 December 2014
CRYSTAL STRUCTURE OF MOUSE APOLIPOPROTEIN M
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