View source for 24tg


==Crystal structure of selenomethionine labelled Streptomyces avermitilis endo-beta-1,6-galactanase==
<StructureSection load='24tg' size='340' side='right'caption='[[24tg]], [[Resolution|resolution]] 2.00&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[24tg]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Streptomyces_avermitilis_MA-4680_=_NBRC_14893 Streptomyces avermitilis MA-4680 = NBRC 14893]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=24TG OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=24TG 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]] 2.001&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MSE:SELENOMETHIONINE'>MSE</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=24tg FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=24tg OCA], [https://pdbe.org/24tg PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=24tg RCSB], [https://www.ebi.ac.uk/pdbsum/24tg PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=24tg ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/Q82CY3_STRAW Q82CY3_STRAW] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Endo-beta-1,6-galactanases hydrolyze beta-1,6-linked galactosyl linkages in galactans, yielding beta-1,6-linked galacto-oligosaccharides, predominantly galactobiose. Here, we report to our knowledge the first crystal structure of an endo-beta-1,6-galactanase, together with its beta-1,6-galactobiose-bound complex, revealing the structural basis for substrate recognition by this enzyme. Endo-beta-1,6-galactanase from Streptomyces avermitilis (Sa16Gal30A) is a member of glycoside hydrolase family 30 (GH30) subfamily 5. Sa16Gal30A consists of two structural domains: a catalytic (beta/alpha)(8)-barrel domain and an appended beta-sandwich domain. The beta-1,6-galactobiose complex structure revealed two beta-1,6-galactobiose molecules bound within the catalytic domain: one at the catalytic site and another at the distinct surface site distal to the catalytic center. This structure represents the first reported structure of a GH30 subfamily 5 enzyme and provides structural insights into the molecular basis of beta-1,6-galactan recognition within the catalytic cleft. Sa16Gal30A possesses three extended regions, loops 2, 4 and 8, in the catalytic domain compared with enzymes from other GH30 subfamilies, and these loops appear to modulate substrate specificity towards beta-1,6-galactan by shaping the architecture of the catalytic cleft. In addition, a secondary beta-1,6-galactan-binding site was identified at a distal location, which may function as a distal subsite, thereby facilitating the efficient hydrolysis of long beta-1,6-galactan chains.

Crystal structure of endo-beta-1,6-galactanase from Streptomyces avermitilis.,Fujimoto Z, Kishine N, Kotake T, Kaneko S Acta Crystallogr D Struct Biol. 2026 Aug 1;82(Pt 8):962-971. doi: , 10.1107/S2059798326006133. Epub 2026 Jul 21. PMID:42478457<ref>PMID:42478457</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 24tg" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Streptomyces avermitilis MA-4680 = NBRC 14893]]
[[Category: Fujimoto Z]]
[[Category: Kaneko S]]
[[Category: Kishine N]]