View source for 1kmb


==SELECTIN-LIKE MUTANT OF MANNOSE-BINDING PROTEIN A==
<StructureSection load='1kmb' size='340' side='right'caption='[[1kmb]], [[Resolution|resolution]] 2.10&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1kmb]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Rattus_norvegicus Rattus norvegicus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1KMB OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1KMB 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]] 2.1&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=CL:CHLORIDE+ION'>CL</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=1kmb FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1kmb OCA], [https://pdbe.org/1kmb PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1kmb RCSB], [https://www.ebi.ac.uk/pdbsum/1kmb PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1kmb ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/MBL1_RAT MBL1_RAT] Calcium-dependent lectin involved in innate immune defense. Binds mannose, fucose and N-acetylglucosamine on different microorganisms and activates the lectin complement pathway. Binds to late apoptotic cells, as well as to apoptotic blebs and to necrotic cells, but not to early apoptotic cells, facilitating their uptake by macrophages (By similarity).
== 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/km/1kmb_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=1kmb ConSurf].
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== Publication Abstract from PubMed ==
Rat serum mannose-binding protein in which residues 211-213 have been changed to the Lys-Lys-Lys sequence found in E-selectin binds HL-60 cells and the oligosaccharide 3'-NeuAc-Le(x). To understand how this mutant, designated K3, mimics the carbohydrate-binding properties of E-selectin, structures of K3 alone and in complexes with 3'-NeuAc-Le(x), 3'-sulfo-Le(x) and 4'-sulfo-Le(x) have been determined at 1.95-2.1 A resolution by X-ray crystallography. The region of K3 that interacts with bound oligosaccharides superimposes closely with the corresponding region of unliganded E-selectin. In each of the oligosaccharide-protein complexes, the 2- and 3-OH of Fuc coordinate Ca2+ and form a network of cooperative hydrogen bonds with amino acid side chains that also coordinate the Ca2+. Lys211 of the K3 mutant, which corresponds to Lys111 of E-selectin, interacts with each of the three bound ligands: the N zeta atom donates a hydrogen bond to the 4-OH of Gal in 3'-NeuAc-Le(x), forms a water-mediated hydrogen bond with the 4-OH of Gal in 3'-sulfo-Le(x), and forms a salt bridge with the sulfate group of 4'-sulfo-Le(x). Lys213 packs against an otherwise exposed aromatic residue and forms a water-mediated hydrogen bond with Lys211 which may help to position that residue for interactions with bound oligosaccharides. These structures are consistent with previous mutagenesis and chemical modification studies which demonstrate the importance of the Ca2+ ligands as well as Lys111 and Lys113 for carbohydrate binding in the selectins, and they provide a structural basis for understanding the selective recognition of negatively charged Le(x) derivatives by the selectins.

Structure of a selectin-like mutant of mannose-binding protein complexed with sialylated and sulfated Lewis(x) oligosaccharides.,Ng KK, Weis WI Biochemistry. 1997 Feb 4;36(5):979-88. PMID:9033386<ref>PMID:9033386</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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==See Also==
*[[Mannose-binding protein|Mannose-binding protein]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Rattus norvegicus]]
[[Category: Ng KK-S]]
[[Category: Weis WI]]