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[[Image: | ==STRUCTURE OF PORCINE PANCREATIC ALPHA-AMYLASE== | ||
<StructureSection load='1dhk' size='340' side='right' caption='[[1dhk]], [[Resolution|resolution]] 1.85Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[1dhk]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Phaseolus_vulgaris Phaseolus vulgaris] and [http://en.wikipedia.org/wiki/Sus_scrofa Sus scrofa]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1DHK OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1DHK FirstGlance]. <br> | |||
</td></tr><tr><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene><br> | |||
<tr><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=PCA:PYROGLUTAMIC+ACID'>PCA</scene></td></tr> | |||
<tr><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Alpha-amylase Alpha-amylase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.1 3.2.1.1] </span></td></tr> | |||
<tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1dhk FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1dhk OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1dhk RCSB], [http://www.ebi.ac.uk/pdbsum/1dhk PDBsum]</span></td></tr> | |||
<table> | |||
== 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/dh/1dhk_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/chain_selection.php?pdb_ID=2ata ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
BACKGROUND: alpha-Amylases catalyze the hydrolysis of glycosidic linkages in starch and other related polysaccharides. The alpha-amylase inhibitor (alpha-Al) from the bean Phaseolus vulgaris belongs to a family of plant defence proteins and is a potent inhibitor of mammalian alpha-amylases. The structure of pig pancreatic alpha-amylase (PPA) in complex with both a carbohydrate inhibitor (acarbose) and a proteinaceous inhibitor (Tendamistat) is known, but the catalytic mechanism is poorly understood. RESULTS: The crystal structure of pig pancreatic alpha-amylase complexed with alpha-Al was refined to 1.85 A resolution. It reveals that in complex with PPA, the inhibitor has the typical dimer structure common to legume lectins. Two hairpin loops extending out from the jellyroll fold of a monomer interact directly with the active site region of the enzyme molecule, with the inhibitor molecule filling the whole substrate-docking region of the PPA. The inhibitor makes substrate-mimetic interactions with binding subsites of the enzyme and targets catalytic residues in the active site. Binding of inhibitor induces structural changes at the active site of the enzyme. CONCLUSIONS: The present analysis reveals that there are extensive interactions between the inhibitor and residues that are highly conserved in the active site of alpha-amylases; alpha-Al1 inactivates PPA through elaborate blockage of substrate-binding sites. It provides a basis to design peptide analogue inhibitors. alpha-Amylase inhibition is of interest from several points of view, for example the treatment of diabetes and for crop protection. | |||
Substrate mimicry in the active center of a mammalian alpha-amylase: structural analysis of an enzyme-inhibitor complex.,Bompard-Gilles C, Rousseau P, Rouge P, Payan F Structure. 1996 Dec 15;4(12):1441-52. PMID:8994970<ref>PMID:8994970</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
==See Also== | ==See Also== | ||
*[[ | *[[Amylase|Amylase]] | ||
== References == | |||
== | <references/> | ||
< | __TOC__ | ||
</StructureSection> | |||
[[Category: Alpha-amylase]] | [[Category: Alpha-amylase]] | ||
[[Category: Phaseolus vulgaris]] | [[Category: Phaseolus vulgaris]] | ||
Revision as of 09:43, 4 September 2014
STRUCTURE OF PORCINE PANCREATIC ALPHA-AMYLASESTRUCTURE OF PORCINE PANCREATIC ALPHA-AMYLASE
Structural highlights
Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedBACKGROUND: alpha-Amylases catalyze the hydrolysis of glycosidic linkages in starch and other related polysaccharides. The alpha-amylase inhibitor (alpha-Al) from the bean Phaseolus vulgaris belongs to a family of plant defence proteins and is a potent inhibitor of mammalian alpha-amylases. The structure of pig pancreatic alpha-amylase (PPA) in complex with both a carbohydrate inhibitor (acarbose) and a proteinaceous inhibitor (Tendamistat) is known, but the catalytic mechanism is poorly understood. RESULTS: The crystal structure of pig pancreatic alpha-amylase complexed with alpha-Al was refined to 1.85 A resolution. It reveals that in complex with PPA, the inhibitor has the typical dimer structure common to legume lectins. Two hairpin loops extending out from the jellyroll fold of a monomer interact directly with the active site region of the enzyme molecule, with the inhibitor molecule filling the whole substrate-docking region of the PPA. The inhibitor makes substrate-mimetic interactions with binding subsites of the enzyme and targets catalytic residues in the active site. Binding of inhibitor induces structural changes at the active site of the enzyme. CONCLUSIONS: The present analysis reveals that there are extensive interactions between the inhibitor and residues that are highly conserved in the active site of alpha-amylases; alpha-Al1 inactivates PPA through elaborate blockage of substrate-binding sites. It provides a basis to design peptide analogue inhibitors. alpha-Amylase inhibition is of interest from several points of view, for example the treatment of diabetes and for crop protection. Substrate mimicry in the active center of a mammalian alpha-amylase: structural analysis of an enzyme-inhibitor complex.,Bompard-Gilles C, Rousseau P, Rouge P, Payan F Structure. 1996 Dec 15;4(12):1441-52. PMID:8994970[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences |
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