1dhk: Difference between revisions
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<jmolCheckbox> | <jmolCheckbox> | ||
<scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/dh/1dhk_consurf.spt"</scriptWhenChecked> | <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/ | <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview03.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/main_output.php?pdb_ID=1dhk ConSurf]. | </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=1dhk ConSurf]. | ||
<div style="clear:both"></div> | <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> | |||
<div class="pdbe-citations 1dhk" style="background-color:#fffaf0;"></div> | |||
==See Also== | ==See Also== | ||
*[[Amylase 3D structures|Amylase 3D structures]] | *[[Amylase 3D structures|Amylase 3D structures]] | ||
== References == | |||
<references/> | |||
__TOC__ | __TOC__ | ||
</StructureSection> | </StructureSection> | ||
Latest revision as of 10:19, 23 October 2024
STRUCTURE OF PORCINE PANCREATIC ALPHA-AMYLASESTRUCTURE OF PORCINE PANCREATIC ALPHA-AMYLASE
Structural highlights
FunctionEvolutionary 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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