1d5i
From Proteopedia
(Difference between revisions)
| (16 intermediate revisions not shown.) | |||
| Line 1: | Line 1: | ||
| - | [[Image:1d5i.gif|left|200px]] | ||
| - | + | ==UNLIGANDED GERMLINE PRECURSOR OF AN OXY-COPE CATALYTIC ANTIBODY== | |
| - | + | <StructureSection load='1d5i' size='340' side='right'caption='[[1d5i]], [[Resolution|resolution]] 2.00Å' scene=''> | |
| - | + | == Structural highlights == | |
| - | | | + | <table><tr><td colspan='2'>[[1d5i]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] and [https://en.wikipedia.org/wiki/Mus_musculus Mus musculus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1D5I OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1D5I 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]] 2Å</td></tr> | |
| - | | | + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CD:CADMIUM+ION'>CD</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=1d5i FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1d5i OCA], [https://pdbe.org/1d5i PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1d5i RCSB], [https://www.ebi.ac.uk/pdbsum/1d5i PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1d5i ProSAT]</span></td></tr> | |
| - | + | </table> | |
| - | + | == Disease == | |
| - | + | [https://www.uniprot.org/uniprot/IGKC_HUMAN IGKC_HUMAN] Defects in IGKC are the cause of immunoglobulin kappa light chain deficiency (IGKCD) [MIM:[https://omim.org/entry/614102 614102]. IGKCD is a disease characterized by the complete absence of immunoglobulin kappa chains.<ref>PMID:3931219</ref> | |
| - | + | == Function == | |
| - | == | + | [https://www.uniprot.org/uniprot/IGKC_HUMAN IGKC_HUMAN] |
| + | == 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/d5/1d5i_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=1d5i ConSurf]. | ||
| + | <div style="clear:both"></div> | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
Antibody AZ-28 was generated against the chairlike transition-state analogue (TSA) 1 and catalyzes the oxy-Cope rearrangement of substrate 2 to product 3. The germline precursor to AZ-28 catalyzes the reaction with a 35-fold higher rate (k(cat)/k(uncat) = 163 000), despite a 40-fold lower binding affinity for TSA.1 (K(D) = 670 nM). To determine the structural basis for the differences in the binding and catalytic properties of the germline and affinity-matured antibodies, the X-ray crystal structures of the unliganded and TSA.1 complex of antibody AZ-28 have been determined at 2.8 and 2.6 A resolution, respectively; the structures of the unliganded and TSA.1 complex of the germline precursor to AZ-28 were both determined at 2. 0 A resolution. In the affinity-matured antibody.hapten complex the TSA is fixed in a catalytically unfavorable conformation by a combination of van der Waals and hydrogen-bonding interactions. The 2- and 5-phenyl substituents of TSA.1 are almost perpendicular to the cyclohexyl ring, leading to decreased orbital overlap and decreased stabilization of the putative transition state. The active site of the germline antibody appears to have an increased degree of flexibility-CDRH3 moves 4.9 A outward from the active site upon binding of TSA.1. We suggest that this conformational flexibility in the germline antibody, which results in a lower binding affinity for TSA.1, allows dynamic changes in the dihedral angle of the 2-phenyl substituent along the reaction coordinate. These conformational changes in turn lead to enhanced orbital overlap and increased catalytic rate. These studies suggest that protein and substrate dynamics play a key role in this antibody-catalyzed reaction. | Antibody AZ-28 was generated against the chairlike transition-state analogue (TSA) 1 and catalyzes the oxy-Cope rearrangement of substrate 2 to product 3. The germline precursor to AZ-28 catalyzes the reaction with a 35-fold higher rate (k(cat)/k(uncat) = 163 000), despite a 40-fold lower binding affinity for TSA.1 (K(D) = 670 nM). To determine the structural basis for the differences in the binding and catalytic properties of the germline and affinity-matured antibodies, the X-ray crystal structures of the unliganded and TSA.1 complex of antibody AZ-28 have been determined at 2.8 and 2.6 A resolution, respectively; the structures of the unliganded and TSA.1 complex of the germline precursor to AZ-28 were both determined at 2. 0 A resolution. In the affinity-matured antibody.hapten complex the TSA is fixed in a catalytically unfavorable conformation by a combination of van der Waals and hydrogen-bonding interactions. The 2- and 5-phenyl substituents of TSA.1 are almost perpendicular to the cyclohexyl ring, leading to decreased orbital overlap and decreased stabilization of the putative transition state. The active site of the germline antibody appears to have an increased degree of flexibility-CDRH3 moves 4.9 A outward from the active site upon binding of TSA.1. We suggest that this conformational flexibility in the germline antibody, which results in a lower binding affinity for TSA.1, allows dynamic changes in the dihedral angle of the 2-phenyl substituent along the reaction coordinate. These conformational changes in turn lead to enhanced orbital overlap and increased catalytic rate. These studies suggest that protein and substrate dynamics play a key role in this antibody-catalyzed reaction. | ||
| - | + | Conformational effects in biological catalysis: an antibody-catalyzed oxy-cope rearrangement.,Mundorff EC, Hanson MA, Varvak A, Ulrich H, Schultz PG, Stevens RC Biochemistry. 2000 Feb 1;39(4):627-32. PMID:10651626<ref>PMID:10651626</ref> | |
| - | + | ||
| - | + | ||
| - | + | ||
| - | + | ||
| - | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |
| - | + | </div> | |
| - | + | <div class="pdbe-citations 1d5i" style="background-color:#fffaf0;"></div> | |
| - | + | ||
| - | + | ||
| - | + | ||
| - | + | ||
| - | + | ||
| - | + | ||
| - | + | ||
| - | + | ==See Also== | |
| + | *[[Monoclonal Antibodies 3D structures|Monoclonal Antibodies 3D structures]] | ||
| + | == References == | ||
| + | <references/> | ||
| + | __TOC__ | ||
| + | </StructureSection> | ||
| + | [[Category: Homo sapiens]] | ||
| + | [[Category: Large Structures]] | ||
| + | [[Category: Mus musculus]] | ||
| + | [[Category: Hanson MA]] | ||
| + | [[Category: Mundorff EC]] | ||
| + | [[Category: Schultz PG]] | ||
| + | [[Category: Stevens RC]] | ||
Current revision
UNLIGANDED GERMLINE PRECURSOR OF AN OXY-COPE CATALYTIC ANTIBODY
| |||||||||||
