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1apn

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Revision as of 14:17, 11 September 2015

THE CRYSTALLOGRAPHIC STRUCTURE OF METAL-FREE CONCANAVALIN A AT 2.5 ANGSTROMS RESOLUTION

Structural highlights

1apn is a 2 chain structure with sequence from Canavalia ensiformis. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum

Function

[CONA_CANEN] D-mannose specific lectin.

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

The three-dimensional structure of demetallized concanavalin A has been determined at 2.5 A resolution and refined to a crystallographic R-factor of 18%. The lectin activity of concanavalin A requires the binding of both a transition metal ion, generally Mn2+, and a Ca2+ ion in two neighboring sites in close proximity to the carbohydrate binding site. Large structural differences between the native and the metal-free lectin are observed in the metal-binding region and consequently for the residues involved in the specific binding of saccharides. The demetallization invokes a series of conformational changes in the protein backbone, apparently initiated mainly by the loss of the calcium ion. Most of the Mn2+ ligands retain their position, but the Ca2+ binding site is destroyed. The Ala207-Asp208 peptide bond, in the beta-strand neighboring the metal-binding sites, undergoes a cis to trans isomerization. The cis conformation for this bond is a highly conserved feature among the leguminous lectins and is critically maintained by the Ca2+ ion in metal-bound concanavalin A. A further and major change adjacent to the isomerized bond is an expansion of the loop containing the monosaccharide ligand residues Leu99 and Tyr100. The dispersion of the ligand residues for the monosaccharide binding site (Asn14, Agr228, Asp208, Leu99, and Tyr100) in metal-free concanavalin A abolishes the lectin's ability to bind saccharides. Since the quaternary structure of legume lectins is essential to their biological role, the tetramer formation was analyzed. In the crystal (pH 5), the metal-free concanavalin A dimers associate into a tetramer that is similar to the native one, but with a drastically reduced number of inter-dimer interactions. This explains the tetramer dissociation into dimers below pH values of 6.5.

Crystallographic structure of metal-free concanavalin A at 2.5 A resolution.,Bouckaert J, Loris R, Poortmans F, Wyns L Proteins. 1995 Dec;23(4):510-24. PMID:8749847^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Bouckaert J, Loris R, Poortmans F, Wyns L. Crystallographic structure of metal-free concanavalin A at 2.5 A resolution. Proteins. 1995 Dec;23(4):510-24. PMID:8749847 doi:10.1002/prot.340230406

1 Structural highlights
2 Function
3 Evolutionary Conservation
4 Publication Abstract from PubMed
5 See Also
6 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1apn"

@@ Line 3: / Line 3: @@
 == Structural highlights ==
 <table><tr><td colspan='2'>[[1apn]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Canavalia_ensiformis Canavalia ensiformis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1APN OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1APN FirstGlance]. <br>
-</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=1apn FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1apn OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1apn RCSB], [http://www.ebi.ac.uk/pdbsum/1apn PDBsum]</span></td></tr>
+</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=1apn FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1apn OCA], [http://pdbe.org/1apn PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1apn RCSB], [http://www.ebi.ac.uk/pdbsum/1apn PDBsum]</span></td></tr>
 </table>
 == Function ==
@@ Line 25: / Line 25: @@
 From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
 </div>
+<div class="pdbe-citations 1apn" style="background-color:#fffaf0;"></div>
 ==See Also==

1apn

From Proteopedia

Revision as of 14:17, 11 September 2015

THE CRYSTALLOGRAPHIC STRUCTURE OF METAL-FREE CONCANAVALIN A AT 2.5 ANGSTROMS RESOLUTION

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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