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== | ==STRUCTURE OF A PANCREATIC ALPHA-AMYLASE BOUND TO A SUBSTRATE ANALOGUE AT 2.03 ANGSTROM RESOLUTION== | ||
<StructureSection load='1jfh' size='340' side='right'caption='[[1jfh]], [[Resolution|resolution]] 2.03Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[1jfh]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Sus_scrofa Sus scrofa]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1JFH OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1JFH 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]] 2.03Å</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>, <scene name='pdbligand=GLC:ALPHA-D-GLUCOSE'>GLC</scene>, <scene name='pdbligand=HG:MERCURY+(II)+ION'>HG</scene>, <scene name='pdbligand=MA1:1,4-DITHIO-ALPHA-D-GLUCOPYRANOSE'>MA1</scene>, <scene name='pdbligand=MA2:4-S-METHYL-4-THIO-ALPHA-D-GLUCOPYRANOSE'>MA2</scene>, <scene name='pdbligand=MA3:O1-METHYL-4-DEOXY-4-THIO-ALPHA-D-GLUCOSE'>MA3</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=1jfh FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1jfh OCA], [https://pdbe.org/1jfh PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1jfh RCSB], [https://www.ebi.ac.uk/pdbsum/1jfh PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1jfh ProSAT]</span></td></tr> | |||
</table> | |||
== Function == | |||
[https://www.uniprot.org/uniprot/AMYP_PIG AMYP_PIG] | |||
== 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/jf/1jfh_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=1jfh ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
The structure of pig pancreatic alpha-amylase in complex with carbohydrate inhibitor and proteinaceous inhibitors is known but the successive events occurring at the catalytic center still remain to be elucidated. The X-ray structure analysis of a crystal of pig pancreatic alpha-amylase (PPA, EC 3.2.1.1.) soaked with an enzyme-resistant substrate analogue, methyl 4,4'-dithio-alpha-maltotrioside, showed electron density corresponding to the binding of substrate analogue molecules at the active site and at the "second binding site." The electron density observed at the active site was interpreted in terms of overlapping networks of oligosaccharides, which show binding of substrate analogue molecules at subsites prior to and subsequent to the cleavage site. A weaker patch of density observed at subsite -1 (using a nomenclature where the site of hydrolysis is taken to be between subsites -1 and +1) was modeled with water molecules. Conformational changes take place upon substrate analogue binding and the "flexible loop" that constitutes the surface edge of the active site is observed in a specific conformation. This confirms that this loop plays an important role in the recognition and binding of the ligand. The crystal structure was refined at 2.03 A resolution, to an R-factor of 16.0 (Rfree, 18.5). | The structure of pig pancreatic alpha-amylase in complex with carbohydrate inhibitor and proteinaceous inhibitors is known but the successive events occurring at the catalytic center still remain to be elucidated. The X-ray structure analysis of a crystal of pig pancreatic alpha-amylase (PPA, EC 3.2.1.1.) soaked with an enzyme-resistant substrate analogue, methyl 4,4'-dithio-alpha-maltotrioside, showed electron density corresponding to the binding of substrate analogue molecules at the active site and at the "second binding site." The electron density observed at the active site was interpreted in terms of overlapping networks of oligosaccharides, which show binding of substrate analogue molecules at subsites prior to and subsequent to the cleavage site. A weaker patch of density observed at subsite -1 (using a nomenclature where the site of hydrolysis is taken to be between subsites -1 and +1) was modeled with water molecules. Conformational changes take place upon substrate analogue binding and the "flexible loop" that constitutes the surface edge of the active site is observed in a specific conformation. This confirms that this loop plays an important role in the recognition and binding of the ligand. The crystal structure was refined at 2.03 A resolution, to an R-factor of 16.0 (Rfree, 18.5). | ||
Structure of a pancreatic alpha-amylase bound to a substrate analogue at 2.03 A resolution.,Qian M, Spinelli S, Driguez H, Payan F Protein Sci. 1997 Nov;6(11):2285-96. PMID:9385631<ref>PMID:9385631</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
[[ | <div class="pdbe-citations 1jfh" style="background-color:#fffaf0;"></div> | ||
[[Category: | |||
==See Also== | |||
*[[Amylase 3D structures|Amylase 3D structures]] | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
[[Category: Large Structures]] | |||
[[Category: Sus scrofa]] | [[Category: Sus scrofa]] | ||
[[Category: Payan | [[Category: Payan F]] | ||
[[Category: Qian | [[Category: Qian M]] | ||