View source for 3wnp


==D308A, F268V, D469Y, A513V, and Y515S quintuple mutant of Bacillus circulans T-3040 cycloisomaltooligosaccharide glucanotransferase complexed with isomaltoundecaose==
<StructureSection load='3wnp' size='340' side='right'caption='[[3wnp]], [[Resolution|resolution]] 2.80&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3wnp]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Niallia_circulans Niallia circulans]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3WNP OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3WNP 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]] 2.8&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=BGC:BETA-D-GLUCOSE'>BGC</scene>, <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=GLC:ALPHA-D-GLUCOSE'>GLC</scene>, <scene name='pdbligand=MES:2-(N-MORPHOLINO)-ETHANESULFONIC+ACID'>MES</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</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=3wnp FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3wnp OCA], [https://pdbe.org/3wnp PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3wnp RCSB], [https://www.ebi.ac.uk/pdbsum/3wnp PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3wnp ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/CTA1_NIACI CTA1_NIACI] Produces cycloisomaltooligosaccharide from dextran containing 7, 8 or 9 glucose units. The enzyme is specific for (1->6)-alpha-D-glucans (dextrans) and, without activity toward (1->4)-alpha-D-glucans, such as amylose. It also has no activity on oligosaccharides, such as amylopectin and pullulan, containing (1->6)-alpha-D-glucosidic linkages at branch points.<ref>PMID:7515357</ref> 
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== Publication Abstract from PubMed ==
Cycloisomaltooligosaccharide glucanotransferase (CITase) is a member of the glycoside hydrolase family 66, and it produces cycloisomaltooligosaccharides (CIs). Small CIs (CI-7-9) and large CIs (CI-&gt;/=10) are designated as oligosaccharide-type CIs (oligo-CIs) and megalosaccharide-type CIs (megalo-CIs), respectively. CITase from Bacillus circulans T-3040 (BcCITase) produces mainly CI-8 with little megalo-CIs. It has two family 35 carbohydrate-binding modules (BcCBM35-1 and BcCBM35-2). BcCBM35-1 is inserted in a catalytic domain of BcCITase, and BcCBM35-2 is located at the C-terminal region. Our previous studies suggested that BcCBM35-1 has two substrate-binding sites (B-1 and B-2). We implemented site-directed mutagenesis of BcCITase to explore the preference for product size on the basis of the 3D structure of BcCITase. Mutational studies provided evidence that B-1 and B-2 contribute to recruiting substrate and maintaining product size, respectively. A mutant (mutant-R) with four mutations (F268V, D469Y, A513V and Y515S) produced three times as much megalo-CIs (CI-10-12) and 1.5 times as much total CIs (CI-7-12) as compared with the wild-type BcCITase. The 3D structure of the substrate-enzyme complex of mutant-R suggested that the modified product size specificity was attributable to the construction of novel substrate-binding sites in the B-2 site of BcCBM35-1, and reactivity was improved by mutation on subsite -3 on the catalytic domain.

Molecular engineering of cycloisomaltooligosaccharide glucanotransferase from Bacillus circulans T-3040: structural determinants for the reaction product size and reactivity.,Suzuki R, Suzuki N, Fujimoto Z, Momma M, Kimura K, Kitamura S, Kimura A, Funane K Biochem J. 2015 Feb 4. PMID:25649478<ref>PMID:25649478</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 3wnp" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Niallia circulans]]
[[Category: Fujimoto Z]]
[[Category: Funane K]]
[[Category: Kimura A]]
[[Category: Kimura K]]
[[Category: Kitamura S]]
[[Category: Momma M]]
[[Category: Suzuki N]]
[[Category: Suzuki R]]