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1yf8
From Proteopedia
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| - | [[Image:1yf8.gif|left|200px]]<br /><applet load="1yf8" size="350" color="white" frame="true" align="right" spinBox="true" | ||
| - | caption="1yf8, resolution 2.80Å" /> | ||
| - | '''Crystal structure of Himalayan mistletoe RIP reveals the presence of a natural inhibitor and a new functionally active sugar-binding site'''<br /> | ||
| - | == | + | ==Crystal structure of Himalayan mistletoe RIP reveals the presence of a natural inhibitor and a new functionally active sugar-binding site== |
| + | <StructureSection load='1yf8' size='340' side='right'caption='[[1yf8]], [[Resolution|resolution]] 2.80Å' scene=''> | ||
| + | == Structural highlights == | ||
| + | <table><tr><td colspan='2'>[[1yf8]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Viscum_album Viscum album]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1YF8 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1YF8 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]] 2.8Å</td></tr> | ||
| + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=BGC:BETA-D-GLUCOSE'>BGC</scene>, <scene name='pdbligand=BMA:BETA-D-MANNOSE'>BMA</scene>, <scene name='pdbligand=GAL:BETA-D-GALACTOSE'>GAL</scene>, <scene name='pdbligand=MAN:ALPHA-D-MANNOSE'>MAN</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene>, <scene name='pdbligand=P6C:2-AMINO-4-ISOPROPYL-PTERIDINE-6-CARBOXYLIC+ACID'>P6C</scene>, <scene name='pdbligand=PRD_900004:beta-lactose'>PRD_900004</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=1yf8 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1yf8 OCA], [https://pdbe.org/1yf8 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1yf8 RCSB], [https://www.ebi.ac.uk/pdbsum/1yf8 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1yf8 ProSAT]</span></td></tr> | ||
| + | </table> | ||
| + | == Function == | ||
| + | [https://www.uniprot.org/uniprot/ML4_VISAL ML4_VISAL] The A chain is responsible for inhibiting protein synthesis through the catalytic inactivation of 60S ribosomal subunits by removing adenine from position 4,324 of 28S rRNA. The B chain binds to cell receptors and probably facilitates the entry into the cell of the A chain; B chains are also responsible for cell agglutination (lectin activity). Inhibits growth of the human tumor cell line Molt4.<ref>PMID:15001393</ref> <ref>PMID:1450445</ref> [UniProtKB:P81446] | ||
| + | == 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/yf/1yf8_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/main_output.php?pdb_ID=1yf8 ConSurf]. | ||
| + | <div style="clear:both"></div> | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
Ribosome-inactivating proteins (RIPs) are toxins involved in plant defense. How the plant prevents autotoxicity is not yet fully understood. The present study is the first structural evidence of a naturally inhibited form of RIP from a plant. Himalayan mistletoe RIP (HmRIP) was purified from Viscum album leaves and crystallized with lactose. The structure was determined by the molecular replacement method and refined at 2.8-A resolution. The crystal structure revealed the presence of high quality non-protein electron density at the active site, into which a pteridine derivative (2-amino 4-isopropyl 6-carboxyl pteridine) was modeled. The carboxyl group of the ligand binds strongly with the key active site residue Arg(162), nullifies the positive charge required for catalysis, and thereby acts as a natural inhibitor. Lectin subunits of RIPs have two active sugar-binding sites present in 1alpha- and 2gamma-subdomains. A third functionally active site has been identified in the 1beta-subdomain of HmRIP. The 1beta-site is active despite the absence of conserved polar sugar-binding residues. Loss of these residues is compensated by the following: (i) the presence of an extended site where the penultimate sugar also interacts with the protein; (ii) the interactions of galactose with the protein main chain carbonyl and amide nitrogen atoms; (iii) the presence of a well defined pocket encircled by four walls; and (iv) a favorable stacking of the galactose ring with Tyr(66) besides the conserved Phe(75). The mode of sugar binding is also distinct at the 1alpha and 2gamma sugar-binding sites. | Ribosome-inactivating proteins (RIPs) are toxins involved in plant defense. How the plant prevents autotoxicity is not yet fully understood. The present study is the first structural evidence of a naturally inhibited form of RIP from a plant. Himalayan mistletoe RIP (HmRIP) was purified from Viscum album leaves and crystallized with lactose. The structure was determined by the molecular replacement method and refined at 2.8-A resolution. The crystal structure revealed the presence of high quality non-protein electron density at the active site, into which a pteridine derivative (2-amino 4-isopropyl 6-carboxyl pteridine) was modeled. The carboxyl group of the ligand binds strongly with the key active site residue Arg(162), nullifies the positive charge required for catalysis, and thereby acts as a natural inhibitor. Lectin subunits of RIPs have two active sugar-binding sites present in 1alpha- and 2gamma-subdomains. A third functionally active site has been identified in the 1beta-subdomain of HmRIP. The 1beta-site is active despite the absence of conserved polar sugar-binding residues. Loss of these residues is compensated by the following: (i) the presence of an extended site where the penultimate sugar also interacts with the protein; (ii) the interactions of galactose with the protein main chain carbonyl and amide nitrogen atoms; (iii) the presence of a well defined pocket encircled by four walls; and (iv) a favorable stacking of the galactose ring with Tyr(66) besides the conserved Phe(75). The mode of sugar binding is also distinct at the 1alpha and 2gamma sugar-binding sites. | ||
| - | + | Crystal structure of himalayan mistletoe ribosome-inactivating protein reveals the presence of a natural inhibitor and a new functionally active sugar-binding site.,Mishra V, Bilgrami S, Sharma RS, Kaur P, Yadav S, Krauspenhaar R, Betzel C, Voelter W, Babu CR, Singh TP J Biol Chem. 2005 May 27;280(21):20712-21. Epub 2005 Mar 17. PMID:15774467<ref>PMID:15774467</ref> | |
| - | + | ||
| - | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |
| - | + | </div> | |
| - | [[Category: | + | <div class="pdbe-citations 1yf8" style="background-color:#fffaf0;"></div> |
| + | == References == | ||
| + | <references/> | ||
| + | __TOC__ | ||
| + | </StructureSection> | ||
| + | [[Category: Large Structures]] | ||
[[Category: Viscum album]] | [[Category: Viscum album]] | ||
| - | + | [[Category: Babu CR]] | |
| - | [[Category: Babu | + | [[Category: Betzel C]] |
| - | [[Category: Betzel | + | [[Category: Bilgrami S]] |
| - | [[Category: Bilgrami | + | [[Category: Kaur P]] |
| - | [[Category: Kaur | + | [[Category: Mishra V]] |
| - | [[Category: Mishra | + | [[Category: Sharma RS]] |
| - | [[Category: Sharma | + | [[Category: Singh TP]] |
| - | [[Category: Singh | + | [[Category: Yadav S]] |
| - | [[Category: Yadav | + | |
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Current revision
Crystal structure of Himalayan mistletoe RIP reveals the presence of a natural inhibitor and a new functionally active sugar-binding site
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Categories: Large Structures | Viscum album | Babu CR | Betzel C | Bilgrami S | Kaur P | Mishra V | Sharma RS | Singh TP | Yadav S
