3wms: Difference between revisions
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''' | ==The crystal structure of Y195I mutant alpha-cyclodextrin glycosyltransferase from Paenibacillus macerans== | ||
<StructureSection load='3wms' size='340' side='right' caption='[[3wms]], [[Resolution|resolution]] 2.30Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[3wms]] is a 1 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3WMS OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3WMS FirstGlance]. <br> | |||
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</scene></td></tr> | |||
<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Cyclomaltodextrin_glucanotransferase Cyclomaltodextrin glucanotransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.4.1.19 2.4.1.19] </span></td></tr> | |||
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3wms FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3wms OCA], [http://www.rcsb.org/pdb/explore.do?structureId=3wms RCSB], [http://www.ebi.ac.uk/pdbsum/3wms PDBsum]</span></td></tr> | |||
</table> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
Cyclodextrin glycosyltransferase (EC 2.4.1.19) (CGTase) is an extracellular bacterial enzyme which has the unique capability of forming cyclodextrins from starch. Our previous investigation revealed that a mutant Y195I alpha-CGTase drastically altered the cyclodextrin specificity by switching toward the synthesis of both beta- and gamma-CDs (Xie et al., 2013a,b). In this study, we determined one X-ray structure of the mutant Y195I alpha-CGTase at 2.3A. The overall structure was similar to that of the typical beta-CGTase from Bacillus circulans 251, with minor difference in flexible domains since they showed about 70% homogeneity of amino acid sequences. The central site with isoleucine tended to be more flexible than tyrosine thus made the sugar chain, during the cyclization process, form a larger cyclodextrin like beta- and gamma-CDs surrounding the central site instead of alpha-CD. Superposition of the structure of Y195I alpha-CGTase with those of beta-CGTase and gamma-CGTase showed that residues Lys232, Lys89 and Arg177 at subsites +2, -3 and -7 could form smaller substrate binding cavity. In summary, the crystal structure revealed that moderate increase of mobility of the central site resulted in the switched product specificity from alpha-CD to beta- and gamma-CDs of the mutant Y195I alpha-CGTase. The space differences alongside the active domain may be another factor that impacts the product specificity of the CGTase. | |||
Structural basis of a mutant Y195I alpha-cyclodextrin glycosyltransferase with switched product specificity from alpha-cyclodextrin to beta-/gamma-cyclodextrin.,Xie T, Hou Y, Li D, Yue Y, Qian S, Chao Y J Biotechnol. 2014 Jul 20;182-183:92-6. doi: 10.1016/j.jbiotec.2014.03.014. Epub , 2014 Mar 15. PMID:24637377<ref>PMID:24637377</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
[[Category: Cyclomaltodextrin glucanotransferase]] | |||
[[Category: Chao, Y P]] | |||
[[Category: Hou, Y J]] | |||
[[Category: Li, D F]] | |||
[[Category: Qian, S J]] | |||
[[Category: Xie, T]] | |||
[[Category: Yue, Y]] | |||
[[Category: Cyclodextrin glycosyltransferase]] | |||
[[Category: Igg-like beta-barrel]] | |||
[[Category: Tim barrel]] | |||
[[Category: Transferase]] | |||