View source for 5hbf


==Crystal structure of human full-length chitotriosidase (CHIT1)==
<StructureSection load='5hbf' size='340' side='right'caption='[[5hbf]], [[Resolution|resolution]] 1.95&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[5hbf]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5HBF OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5HBF 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]] 1.95&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=GOL:GLYCEROL'>GOL</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=5hbf FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5hbf OCA], [https://pdbe.org/5hbf PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5hbf RCSB], [https://www.ebi.ac.uk/pdbsum/5hbf PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5hbf ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/CHIT1_HUMAN CHIT1_HUMAN] Degrades chitin, chitotriose and chitobiose. May participate in the defense against nematodes and other pathogens. Isoform 3 has no enzymatic activity.<ref>PMID:7592832</ref> <ref>PMID:7836450</ref> <ref>PMID:9748235</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Chitinases are enzymes that catalyze the hydrolysis of chitin. Human chitotriosidase (CHIT1) is one of the two active human chitinases, involved in the innate immune response and highly expressed in a variety of diseases. CHIT1 is composed of a catalytic domain linked by a hinge to its chitin binding domain (ChBD). This latter domain belongs to the carbohydrate-binding module family 14 (CBM14 family) and facilitates binding to chitin. So far, the available crystal structures of the human chitinase CHIT1 and the Acidic Mammalian Chitinase (AMCase) comprise only their catalytic domain. Here, we report a crystallization strategy combining cross-seeding and micro-seeding cycles which allowed us to obtain the first crystal structure of the full length CHIT1 (CHIT1-FL) at 1.95 A resolution. The CHIT1 chitin binding domain (ChBDCHIT1) structure shows a distorted beta-sandwich 3D fold, typical of CBM14 family members. Accordingly, ChBDCHIT1 presents six conserved cysteine residues forming three disulfide bridges and several exposed aromatic residues that probably are involved in chitin binding, including the highly conserved Trp465 in a surface- exposed conformation. Furthermore, ChBDCHIT1 presents a positively charged surface which may be involved in electrostatic interactions. Our data highlight the strong structural conservation of CBM14 family members and uncover the structural similarity between the human ChBDCHIT1, tachycitin and house mite dust allergens. Overall, our new CHIT1-FL structure, determined with an adapted crystallization approach, is one of the few complete bi-modular chitinase structures available and reveals the structural features of a human CBM14 domain.

X-Ray Crystal Structure of the Full Length Human Chitotriosidase (CHIT1) Reveals Features of Its Chitin Binding Domain.,Fadel F, Zhao Y, Cousido-Siah A, Ruiz FX, Mitschler A, Podjarny A PLoS One. 2016 Apr 25;11(4):e0154190. doi: 10.1371/journal.pone.0154190., eCollection 2016. PMID:27111557<ref>PMID:27111557</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 5hbf" style="background-color:#fffaf0;"></div>

==See Also==
*[[Chitinase 3D structures|Chitinase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Cousido-Siah A]]
[[Category: Fadel F]]
[[Category: Mitschler A]]
[[Category: Podjarny A]]
[[Category: Ruiz FX]]
[[Category: Zhao Y]]