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3lc9
From Proteopedia
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| - | [[ | + | ==Ricin A-chain variant 1-33/44-198 with engineered disulfide bond== |
| + | <StructureSection load='3lc9' size='340' side='right' caption='[[3lc9]], [[Resolution|resolution]] 2.28Å' scene=''> | ||
| + | == Structural highlights == | ||
| + | <table><tr><td colspan='2'>[[3lc9]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Ricinus_communis Ricinus communis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3LC9 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3LC9 FirstGlance]. <br> | ||
| + | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></td></tr> | ||
| + | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[3bjg|3bjg]]</td></tr> | ||
| + | <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/rRNA_N-glycosylase rRNA N-glycosylase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.2.22 3.2.2.22] </span></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=3lc9 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3lc9 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=3lc9 RCSB], [http://www.ebi.ac.uk/pdbsum/3lc9 PDBsum]</span></td></tr> | ||
| + | </table> | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
| + | RTA1-33/44-198 is a catalytically inactive, single-domain derivative of the ricin toxin A-chain (RTA) engineered to serve as a stable protein scaffold for presentation of native immunogenic epitopes (Olson et al., Protein Eng Des Sel 2004;17:391-397). To improve the stability and solubility of RTA1-33/44-198 further, we have undertaken the design challenge of introducing a disulfide (SS) bond. Nine pairs of residues were selected for placement of the SS-bond based on molecular dynamics simulation studies of the modeled single-domain chain. Disulfide formation at either of two positions (R48C/T77C or V49C/E99C) involving a specific surface loop (44-55) increased the protein melting temperature by ~5 degrees C compared with RTA1-33/44-198 and by ~13 degrees C compared with RTA. Prolonged stability studies of the R48C/T77C variant (> 60 days at 37 degrees C, pH 7.4) confirmed a > 40% reduction in self-aggregation compared with RTA1-33/44-198 lacking the SS-bond. The R48C/T77C variant retained affinity for anti-RTA antibodies capable of neutralizing ricin toxin, including a monoclonal that recognizes a human B-cell epitope. Introduction of either R48C/T77C or V49C/E99C promoted crystallization of RTA1-33/44-198, and the X-ray structures of the variants were solved to 2.3 A or 2.1 A resolution, respectively. The structures confirm formation of an intramolecular SS-bond, and reveal a single-domain fold that is significantly reduced in volume compared with RTA. Loop 44 to 55 is partly disordered as predicted by simulations, and is positioned to form self-self interactions between symmetry-related molecules. We discuss the importance of RTA loop 34 to 55 as a nucleus for unfolding and aggregation, and draw conclusions for ongoing structure-based minimalist design of RTA-based immunogens. | ||
| - | + | Introduction of a disulfide bond leads to stabilization and crystallization of a ricin immunogen.,Compton JR, Legler PM, Clingan BV, Olson MA, Millard CB Proteins. 2011 Apr;79(4):1048-60. doi: 10.1002/prot.22933. Epub 2011 Jan, 5. PMID:21387408<ref>PMID:21387408</ref> | |
| - | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |
| - | + | </div> | |
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==See Also== | ==See Also== | ||
*[[Ricin|Ricin]] | *[[Ricin|Ricin]] | ||
| - | + | == References == | |
| - | == | + | <references/> |
| - | < | + | __TOC__ |
| + | </StructureSection> | ||
[[Category: Ricinus communis]] | [[Category: Ricinus communis]] | ||
[[Category: RRNA N-glycosylase]] | [[Category: RRNA N-glycosylase]] | ||
| - | [[Category: Compton, J R | + | [[Category: Compton, J R]] |
| - | [[Category: Legler, P M | + | [[Category: Legler, P M]] |
| - | [[Category: Millard, C B | + | [[Category: Millard, C B]] |
[[Category: Disulfide bond]] | [[Category: Disulfide bond]] | ||
[[Category: Hydrolase]] | [[Category: Hydrolase]] | ||
Revision as of 09:42, 9 December 2014
Ricin A-chain variant 1-33/44-198 with engineered disulfide bond
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