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[[Image: | ==REFINED CRYSTAL STRUCTURES OF GLUCOAMYLASE FROM ASPERGILLUS AWAMORI VAR. X100== | ||
<StructureSection load='1glm' size='340' side='right' caption='[[1glm]], [[Resolution|resolution]] 2.40Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[1glm]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Aspergillus_awamori Aspergillus awamori]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1GLM OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1GLM FirstGlance]. <br> | |||
</td></tr><tr><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=MAN:ALPHA-D-MANNOSE'>MAN</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene><br> | |||
<tr><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Glucan_1,4-alpha-glucosidase Glucan 1,4-alpha-glucosidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.3 3.2.1.3] </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=1glm FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1glm OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1glm RCSB], [http://www.ebi.ac.uk/pdbsum/1glm 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/gl/1glm_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 == | |||
The refined crystal structures of a proteolytic fragment of glucoamylase from Aspergillus awamori var. X100 have been determined at pH 6 and 4 to a resolution of 2.2 A and 2.4 A, respectively. The models include the equivalent of residues 1 to 471 of glucoamylase from Aspergillus niger and a complete interpretation of the solvent structure. The R-factors of the pH 6 and 4 structures are 0.14 and 0.12, respectively, with root-mean-square deviations of 0.014 A and 0.012 A from expected bondlengths. The enzyme has the general shape of a doughnut. The "hole" of the doughnut consists of a barrier of hydrophobic residues at the center, which separates two water-filled voids, one of which serves as the active site. Three clusters of water molecules extend laterally from the active site. One of the lateral clusters connects the deepest recess of the active site to the surface of the enzyme. The most significant difference in the pH 4 and 6 structures is the thermal parameter of water 500, the putative nucleophile in the hydrolysis of maltooligosaccharides. Water 500 is associated more tightly with the enzyme at pH 4 (the pH of optimum catalysis) than at pH 6. In contrast to water 500, Glu179, the putative catalytic acid of glucoamylase, retains the same conformation in both structures and is in an environment that would favor the ionized, rather than the acid form of the side-chain. Glycosyl chains of 5 and 8 sugar residues are linked to Asparagines 171 and 395, respectively. The conformations of the two glycosyl chains are similar, being superimposable on each other with a root-mean-square discrepancy of 1.9 A. The N-glycosyl chains hydrogen bond to the surface of the protein through their terminal sugars, but otherwise do not interact strongly with the enzyme. The structures have ten serine/threonine residues, to each of which is linked a single mannose sugar. The structure of the ten O-glycosylated residues taken together suggests a well-defined conformation for proteins that have extensive O-glycosylation of their polypeptide chain. | |||
Refined crystal structures of glucoamylase from Aspergillus awamori var. X100.,Aleshin AE, Hoffman C, Firsov LM, Honzatko RB J Mol Biol. 1994 May 13;238(4):575-91. PMID:8176747<ref>PMID:8176747</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: Aspergillus awamori]] | [[Category: Aspergillus awamori]] | ||
[[Category: Glucan 1,4-alpha-glucosidase]] | [[Category: Glucan 1,4-alpha-glucosidase]] | ||
Revision as of 15:17, 28 September 2014
REFINED CRYSTAL STRUCTURES OF GLUCOAMYLASE FROM ASPERGILLUS AWAMORI VAR. X100REFINED CRYSTAL STRUCTURES OF GLUCOAMYLASE FROM ASPERGILLUS AWAMORI VAR. X100
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 PubMedThe refined crystal structures of a proteolytic fragment of glucoamylase from Aspergillus awamori var. X100 have been determined at pH 6 and 4 to a resolution of 2.2 A and 2.4 A, respectively. The models include the equivalent of residues 1 to 471 of glucoamylase from Aspergillus niger and a complete interpretation of the solvent structure. The R-factors of the pH 6 and 4 structures are 0.14 and 0.12, respectively, with root-mean-square deviations of 0.014 A and 0.012 A from expected bondlengths. The enzyme has the general shape of a doughnut. The "hole" of the doughnut consists of a barrier of hydrophobic residues at the center, which separates two water-filled voids, one of which serves as the active site. Three clusters of water molecules extend laterally from the active site. One of the lateral clusters connects the deepest recess of the active site to the surface of the enzyme. The most significant difference in the pH 4 and 6 structures is the thermal parameter of water 500, the putative nucleophile in the hydrolysis of maltooligosaccharides. Water 500 is associated more tightly with the enzyme at pH 4 (the pH of optimum catalysis) than at pH 6. In contrast to water 500, Glu179, the putative catalytic acid of glucoamylase, retains the same conformation in both structures and is in an environment that would favor the ionized, rather than the acid form of the side-chain. Glycosyl chains of 5 and 8 sugar residues are linked to Asparagines 171 and 395, respectively. The conformations of the two glycosyl chains are similar, being superimposable on each other with a root-mean-square discrepancy of 1.9 A. The N-glycosyl chains hydrogen bond to the surface of the protein through their terminal sugars, but otherwise do not interact strongly with the enzyme. The structures have ten serine/threonine residues, to each of which is linked a single mannose sugar. The structure of the ten O-glycosylated residues taken together suggests a well-defined conformation for proteins that have extensive O-glycosylation of their polypeptide chain. Refined crystal structures of glucoamylase from Aspergillus awamori var. X100.,Aleshin AE, Hoffman C, Firsov LM, Honzatko RB J Mol Biol. 1994 May 13;238(4):575-91. PMID:8176747[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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