View source for 4lgx


==Structure of Chitinase D from Serratia proteamaculans revealed an unusually constrained substrate binding site==
<StructureSection load='4lgx' size='340' side='right'caption='[[4lgx]], [[Resolution|resolution]] 1.49&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4lgx]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Serratia_proteamaculans_568 Serratia proteamaculans 568]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4LGX OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4LGX 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]] 1.49&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ACT:ACETATE+ION'>ACT</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=OMT:S-DIOXYMETHIONINE'>OMT</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=4lgx FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4lgx OCA], [https://pdbe.org/4lgx PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4lgx RCSB], [https://www.ebi.ac.uk/pdbsum/4lgx PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4lgx ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/A8GFD6_SERP5 A8GFD6_SERP5] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Serratia proteamaculans chitinase-D (SpChiD) has a unique combination of hydrolytic and transglycosylation (TG) activities. The TG activity of SpChiD can be used for large-scale production of chito-oligosaccharides (CHOS). The multiple activities (hydrolytic and/or chitobiase activities and TG) of SpChiD appear to be strongly influenced by the substrate-binding cleft. Here, we report the unique property of SpChiD substrate-binding cleft, wherein, the residues Tyr28, Val35 and Thr36 control chitobiase activity and the residues Trp160 and Trp290 are crucial for TG activity. Mutants with reduced (V35G and T36G/F) or no (SpChiDDelta30-42 and Y28A) chitobiase activity produced higher amounts of the quantifiable even-chain TG product with degree of polymerization (DP)-6, indicating that the chitobiase and TG activities are inversely related. In addition to its unprecedented catalytic properties, unlike other chitinases, the single modular SpChiD showed dual unfolding transitions. Ligand-induced thermal stability studies with the catalytically inactive mutant of SpChiD (E153A) showed that the transition temperature increased upon binding of CHOS with DP2-6. Isothermal titration calorimetry experiments revealed the exceptionally high binding affinities for E153A to CHOS with DP2-6. These observations strongly support that the architecture of SpChiD substrate-binding cleft adopted to control chitobiase and TG activities, in addition to usual chitinase-mediated hydrolysis.

Inverse relationship between chitobiase and transglycosylation activities of chitinase-D from Serratia proteamaculans revealed by mutational and biophysical analyses.,Madhuprakash J, Bobbili KB, Moerschbacher BM, Singh TP, Swamy MJ, Podile AR Sci Rep. 2015 Oct 23;5:15657. doi: 10.1038/srep15657. PMID:26493546<ref>PMID:26493546</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4lgx" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Serratia proteamaculans 568]]
[[Category: Kaur P]]
[[Category: Kumar S]]
[[Category: Madhuprakash J]]
[[Category: Podile AR]]
[[Category: Sharma S]]
[[Category: Singh A]]
[[Category: Singh TP]]
[[Category: Sinha M]]