View source for 4uzn


==The native structure of the family 46 carbohydrate-binding module (CBM46) of endo-beta-1,4-glucanase B (Cel5B) from Bacillus halodurans==
<StructureSection load='4uzn' size='340' side='right'caption='[[4uzn]], [[Resolution|resolution]] 2.46&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4uzn]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Alkalihalobacillus_halodurans Alkalihalobacillus halodurans]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4UZN OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4UZN 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]] 2.46&#8491;</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=4uzn FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4uzn OCA], [https://pdbe.org/4uzn PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4uzn RCSB], [https://www.ebi.ac.uk/pdbsum/4uzn PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4uzn ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/Q9KF82_HALH5 Q9KF82_HALH5] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Structural carbohydrates comprise an extraordinary source of energy that remains poorly utilized by the biofuel sector as enzymes have restricted access to their substrates within the intricacy of plant cell walls. Carbohydrate Active enZYmes (CAZYmes) that target recalcitrant polysaccharides are modular enzymes containing non-catalytic Carbohydrate Binding Modules (CBMs) that direct enzymes to their cognate substrate, thus potentiating catalysis. In general, CBMs are functionally and structurally autonomous from their associated catalytic domains from which they are separated through flexible linker sequences. Here we show that a C-terminal CBM46 derived from BhCel5B, a Bacillus halodurans endoglucanase, does not interact with beta-glucans independently but, uniquely, acts co-operatively with the catalytic domain of the enzyme in substrate recognition. The structure of BhCBM46 revealed a beta-sandwich fold that abuts onto the region of the substrate binding cleft upstream of the active site. BhCBM46 as a discrete entity is unable to bind to beta-glucans. Removal of BhCBM46 from BhCel5B, however, abrogates binding to beta-1,3-1,4-glucans while substantially decreasing the affinity for decorated beta-1,4-glucan homopolymers such as xyloglucan. The CBM46 was shown to contribute to xyloglucan hydrolysis only in the context of intact plant cell walls, but potentiates enzymatic activity against purified beta-1,3-1,4-glucans in solution or within the cell wall. This report reveals the mechanism by which a CBM can promote enzyme activity through direct interaction with the substrate or by targeting regions of the plant cell wall where the target glucan is abundant.

Family 46 Carbohydrate-Binding Modules contribute to the enzymatic hydrolysis of xyloglucan and beta-1,3-1,4-glucans through distinct mechanisms.,Venditto I, Najmudin S, Luis AS, Ferreira LM, Sakka K, Knox JP, Gilbert HJ, Fontes CM J Biol Chem. 2015 Feb 23. pii: jbc.M115.637827. PMID:25713075<ref>PMID:25713075</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4uzn" style="background-color:#fffaf0;"></div>

==See Also==
*[[Glucanase 3D structures|Glucanase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Alkalihalobacillus halodurans]]
[[Category: Large Structures]]
[[Category: Ferreira LMA]]
[[Category: Fontes CMGA]]
[[Category: Najmudin S]]
[[Category: Sakka K]]
[[Category: Santos H]]
[[Category: Venditto I]]