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1fmi
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==CRYSTAL STRUCTURE OF HUMAN CLASS I ALPHA1,2-MANNOSIDASE== | ==CRYSTAL STRUCTURE OF HUMAN CLASS I ALPHA1,2-MANNOSIDASE== | ||
| - | <StructureSection load='1fmi' size='340' side='right' caption='[[1fmi]], [[Resolution|resolution]] 1.90Å' scene=''> | + | <StructureSection load='1fmi' size='340' side='right'caption='[[1fmi]], [[Resolution|resolution]] 1.90Å' scene=''> |
== Structural highlights == | == Structural highlights == | ||
| - | <table><tr><td colspan='2'>[[1fmi]] is a 1 chain structure with sequence from [ | + | <table><tr><td colspan='2'>[[1fmi]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1FMI OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1FMI FirstGlance]. <br> |
| - | </td></tr><tr id=' | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.9Å</td></tr> |
| - | <tr id=' | + | <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=SO4:SULFATE+ION'>SO4</scene></td></tr> |
| - | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[ | + | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1fmi FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1fmi OCA], [https://pdbe.org/1fmi PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1fmi RCSB], [https://www.ebi.ac.uk/pdbsum/1fmi PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1fmi ProSAT]</span></td></tr> |
</table> | </table> | ||
== Disease == | == Disease == | ||
| - | [ | + | [https://www.uniprot.org/uniprot/MA1B1_HUMAN MA1B1_HUMAN] Defects in MAN1B1 are the cause of mental retardation autosomal recessive type 15 (MRT15) [MIM:[https://omim.org/entry/614202 614202]. Mental retardation is characterized by significantly below average general intellectual functioning associated with impairments in adaptative behavior and manifested during the developmental period.<ref>PMID:21763484</ref> |
== Function == | == Function == | ||
| - | [ | + | [https://www.uniprot.org/uniprot/MA1B1_HUMAN MA1B1_HUMAN] Involved in glycoprotein quality control targeting of misfolded glycoproteins for degradation. It primarily trims a single alpha-1,2-linked mannose residue from Man(9)GlcNAc(2) to produce Man(8)GlcNAc(2), but at high enzyme concentrations, as found in the ER quality control compartment (ERQC), it further trims the carbohydrates to Man(5-6)GlcNAc(2).<ref>PMID:12090241</ref> <ref>PMID:18003979</ref> |
== Evolutionary Conservation == | == Evolutionary Conservation == | ||
[[Image:Consurf_key_small.gif|200px|right]] | [[Image:Consurf_key_small.gif|200px|right]] | ||
Check<jmol> | Check<jmol> | ||
<jmolCheckbox> | <jmolCheckbox> | ||
| - | <scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/fm/1fmi_consurf.spt"</scriptWhenChecked> | + | <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/fm/1fmi_consurf.spt"</scriptWhenChecked> |
<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | ||
<text>to colour the structure by Evolutionary Conservation</text> | <text>to colour the structure by Evolutionary Conservation</text> | ||
</jmolCheckbox> | </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/ | + | </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=1fmi ConSurf]. |
<div style="clear:both"></div> | <div style="clear:both"></div> | ||
| - | <div style="background-color:#fffaf0;"> | ||
| - | == Publication Abstract from PubMed == | ||
| - | Endoplasmic reticulum (ER) class I alpha1,2-mannosidase (also known as ER alpha-mannosidase I) is a critical enzyme in the maturation of N-linked oligosaccharides and ER-associated degradation. Trimming of a single mannose residue acts as a signal to target misfolded glycoproteins for degradation by the proteasome. Crystal structures of the catalytic domain of human ER class I alpha1,2-mannosidase have been determined both in the presence and absence of the potent inhibitors kifunensine and 1-deoxymannojirimycin. Both inhibitors bind to the protein at the bottom of the active-site cavity, with the essential calcium ion coordinating the O-2' and O-3' hydroxyls and stabilizing the six-membered rings of both inhibitors in a (1)C(4) conformation. This is the first direct evidence of the role of the calcium ion. The lack of major conformational changes upon inhibitor binding and structural comparisons with the yeast alpha1, 2-mannosidase enzyme-product complex suggest that this class of inverting enzymes has a novel catalytic mechanism. The structures also provide insight into the specificity of this class of enzymes and provide a blueprint for the future design of novel inhibitors that prevent degradation of misfolded proteins in genetic diseases. | ||
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| - | Structural basis for catalysis and inhibition of N-glycan processing class I alpha 1,2-mannosidases.,Vallee F, Karaveg K, Herscovics A, Moremen KW, Howell PL J Biol Chem. 2000 Dec 29;275(52):41287-98. PMID:10995765<ref>PMID:10995765</ref> | ||
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| - | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | ||
| - | </div> | ||
| - | <div class="pdbe-citations 1fmi" style="background-color:#fffaf0;"></div> | ||
==See Also== | ==See Also== | ||
| - | *[[Mannosidase|Mannosidase]] | + | *[[Mannosidase 3D structures|Mannosidase 3D structures]] |
== References == | == References == | ||
<references/> | <references/> | ||
__TOC__ | __TOC__ | ||
</StructureSection> | </StructureSection> | ||
| - | [[Category: | + | [[Category: Homo sapiens]] |
| - | [[Category: | + | [[Category: Large Structures]] |
| - | [[Category: Herscovics | + | [[Category: Herscovics A]] |
| - | [[Category: Howell | + | [[Category: Howell PL]] |
| - | [[Category: Karaveg | + | [[Category: Karaveg K]] |
| - | [[Category: Moremen | + | [[Category: Moremen KW]] |
| - | [[Category: Vallee | + | [[Category: Vallee F]] |
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Current revision
CRYSTAL STRUCTURE OF HUMAN CLASS I ALPHA1,2-MANNOSIDASE
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