View source for 2z48


==Crystal Structure of Hemolytic Lectin CEL-III Complexed with GalNac==
<StructureSection load='2z48' size='340' side='right'caption='[[2z48]], [[Resolution|resolution]] 1.70&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2z48]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Cucumaria_echinata Cucumaria echinata]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2Z48 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2Z48 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]] 1.7&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=A2G:N-ACETYL-2-DEOXY-2-AMINO-GALACTOSE'>A2G</scene>, <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=NGA:N-ACETYL-D-GALACTOSAMINE'>NGA</scene>, <scene name='pdbligand=PCA:PYROGLUTAMIC+ACID'>PCA</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=2z48 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2z48 OCA], [https://pdbe.org/2z48 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2z48 RCSB], [https://www.ebi.ac.uk/pdbsum/2z48 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2z48 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/CEL3_CUCEC CEL3_CUCEC] Galactose/N-acetylgalactosamine (Gal/GalNAc)-binding lectin with hemolytic activity. Favors saccharides that have a beta-1,4 linkage at the non-reducing end rather than saccharides having alpha-1,6 or alpha-1,4 linkages. Binds lactose, lactulose, GalNAc, galactosamine, methyl alpha-galactopyranoside, methyl beta-galactopyranoside, N-acetyllactosamine, p-nitrophenyl beta-D-galactopyranoside (pNP-Gal), p-nitrophenyl N-acetyl-beta-D-galactosaminide (pNP-GalNAc), asialofetuin, and human erythrocyte membrane lipids lactosyl ceramide (LacCer) and globoside globotetraosylceramide (Gb4Cer). Binds moderately to galactose, melibiose, raffinose, fucose, methyl alpha-galactoside and methyl beta-galactoside. Binds weakly to glucose, mannose and N-acetylglucosamine (GlcNAc) (PubMed:10101284, PubMed:10478454, PubMed:10923802, PubMed:11471734, PubMed:11983084, PubMed:14561725, PubMed:15194688, PubMed:17977832, PubMed:18159942, PubMed:19356139, PubMed:19420692, PubMed:22313748, PubMed:23470749, PubMed:23545649, PubMed:23583369, PubMed:24652284, PubMed:27101707, PubMed:7798179, PubMed:7876091, PubMed:8663224, PubMed:9058193, PubMed:9133626, PubMed:9305736, PubMed:9692203, PubMed:9805377, PubMed:9990124). Has hemolytic activity towards human (A, B and O-type), rabbit and rat erythrocytes, but not towards mouse, chicken or horse erythrocytes (PubMed:10101284, PubMed:10923802, PubMed:11471734, PubMed:18159942, PubMed:19356139, PubMed:19420692, PubMed:22313748, PubMed:23583369, PubMed:27101707, PubMed:7798179, PubMed:7876091, PubMed:8663224, PubMed:9058193, PubMed:9692203, PubMed:9805377). Forms ion-permeable transmembrane pores in the erythrocyte membrane as well as in artificial liposomes containing human erythrocyte membrane lipids LacCer, Gb4Cer and galactosyl ceramide (GalCer) leading to destruction of the membrane (PubMed:10478454, PubMed:7876091, PubMed:9133626, PubMed:9990124). Has hemagglutinating activity towards rabbit, human and rat erythrocytes, and at relatively high concentrations towards chicken and horse erythrocytes, but not towards mouse erythrocytes (PubMed:10923802, PubMed:11471734, PubMed:14561725, PubMed:18159942, PubMed:19420692, PubMed:7798179, PubMed:9692203, PubMed:9805377, PubMed:9990124). Has dose-dependent cytotoxic effect on Madin-Darby canine kidney (MDCK), African green monkey kidney (Vero) and human epithelia carcinoma (HeLa) cell lines, but Chinese hamster ovary (CHO), rat sarcoma (XC) and potoroo rat kangaroo kidney (PtK1) cells are highly resistant to the cytotoxic effect of this protein (PubMed:10101284, PubMed:9133626). Impairs malaria parasite development in malaria parasite infected transgenic A.stephensi mosquitoes expressing this protein specifically in their midguts. Binds to ookinetes and leads to strong dose-dependent inhibition of ookinete formation in vitro. Leads to severely impaired oocyst formation and significantly reduced sporozoite production of rodent malaria parasite P.berghei in the salivary glands of the transgenic mosquitoes. The parasite transmission to uninfected mice (vectorial competence) of these mosquitoes is significantly impaired. Leads also to severely impaired oocyst formation of human malaria parasite P.falciparum in transgenic mosquitoes fed on mature P.falciparum gametocyte cultures (PubMed:18159942). May be involved in defense mechanisms acting as a toxic protein to foreign microorganisms (PubMed:7876091, PubMed:9133626). May act in defense against predators (PubMed:24652284).<ref>PMID:10101284</ref> <ref>PMID:10478454</ref> <ref>PMID:10923802</ref> <ref>PMID:11471734</ref> <ref>PMID:11983084</ref> <ref>PMID:14561725</ref> <ref>PMID:15194688</ref> <ref>PMID:17977832</ref> <ref>PMID:18159942</ref> <ref>PMID:19356139</ref> <ref>PMID:19420692</ref> <ref>PMID:22313748</ref> <ref>PMID:23470749</ref> <ref>PMID:23545649</ref> <ref>PMID:23583369</ref> <ref>PMID:24652284</ref> <ref>PMID:27101707</ref> <ref>PMID:7798179</ref> <ref>PMID:7876091</ref> <ref>PMID:8663224</ref> <ref>PMID:9058193</ref> <ref>PMID:9133626</ref> <ref>PMID:9305736</ref> <ref>PMID:9692203</ref> <ref>PMID:9805377</ref> <ref>PMID:9990124</ref> 
== 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/z4/2z48_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=2z48 ConSurf].
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== Publication Abstract from PubMed ==
CEL-III is a Ca(2+)-dependent hemolytic lectin, isolated from the marine invertebrate Cucumaria echinata. The three-dimensional structure of CEL-III/GalNAc and CEL-III/methyl alpha-galactoside complexes was solved by x-ray crystallographic analysis. In these complexes, five carbohydrate molecules were found to be bound to two carbohydrate-binding domains (domains 1 and 2) located in the N-terminal 2/3 portion of the polypeptide and that contained beta-trefoil folds similar to ricin B-chain. The 3-OH and 4-OH of bound carbohydrate molecules were coordinated with Ca(2+) located at the subdomains 1alpha, 1gamma, 2alpha, 2beta, and 2gamma, simultaneously forming hydrogen bond networks with nearby amino acid side chains, which is similar to carbohydrate binding in C-type lectins. The binding of carbohydrates was further stabilized by aromatic amino acid residues, such as tyrosine and tryptophan, through a stacking interaction with the hydrophobic face of carbohydrates. The importance of amino acid residues in the carbohydrate-binding sites was confirmed by the mutational analyses. The orientation of bound GalNAc and methyl alpha-galactoside was similar to the galactose moiety of lactose bound to the carbohydrate-binding site of the ricin B-chain, although the ricin B-chain does not require Ca(2+) ions for carbohydrate binding. The binding of the carbohydrates induced local structural changes in carbohydrate-binding sites in subdomains 2alpha and 2beta. Binding of GalNAc also induced a slight change in the main chain structure of domain 3, which could be related to the conformational change upon binding of specific carbohydrates to induce oligomerization of the protein.

C-type lectin-like carbohydrate recognition of the hemolytic lectin CEL-III containing ricin-type -trefoil folds.,Hatakeyama T, Unno H, Kouzuma Y, Uchida T, Eto S, Hidemura H, Kato N, Yonekura M, Kusunoki M J Biol Chem. 2007 Dec 28;282(52):37826-35. Epub 2007 Oct 31. PMID:17977832<ref>PMID:17977832</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Cucumaria echinata]]
[[Category: Large Structures]]
[[Category: Eto S]]
[[Category: Hatakeyama T]]
[[Category: Hidemura H]]
[[Category: Kouzuma Y]]
[[Category: Uchida T]]
[[Category: Unno H]]