View source for 9ta3


==Cryo-EM structure of Heyndrickxia coagulans beta-galactosidase==
<StructureSection load='9ta3' size='340' side='right'caption='[[9ta3]], [[Resolution|resolution]] 2.97&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[9ta3]] is a 6 chain structure with sequence from [https://en.wikipedia.org/wiki/Weizmannia_coagulans Weizmannia coagulans]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=9TA3 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=9TA3 FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 2.97&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</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=9ta3 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=9ta3 OCA], [https://pdbe.org/9ta3 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=9ta3 RCSB], [https://www.ebi.ac.uk/pdbsum/9ta3 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=9ta3 ProSAT]</span></td></tr>
</table>
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== Publication Abstract from PubMed ==
Thermostable beta-galactosidases represent promising biocatalysts for lactose hydrolysis and production of structurally defined galacto-oligosaccharides (GOS). Here we report the cryo-EM structure of the glycoside hydrolase family 42 (GH42) beta-galactosidase from Heyndrickxia coagulans MA-13 (HcGalB), determined at 2.97 A resolution. HcGalB adopts a canonical tripartite architecture and assembles into a barrel-like homo-hexamer composed of two staggered trimers that interact in an unusual top-to-top configuration. This quaternary arrangement contributes not only to structural stability but also to the modulation of substrate channeling and catalytic properties. Molecular docking revealed a surface groove shaped by conserved aromatic residues that might guide the substrate towards the catalytic pocket. Moreover, the structural data provide a mechanistic rationale for the efficient transgalactosylation activity of HcGalB, which predominantly generates beta (1 --&gt; 3)-linked GOS, along with beta(1 --&gt; 6) and beta(1 --&gt; 4) linkages, as confirmed by 2D Nuclear Magnetic Resonance. Overall, these findings expand the structural landscape of GH42 enzymes and identify architecture-specific determinants that can be leveraged to optimize GH42 catalysts for industrial and functional food applications.

CryoEM structural analysis of a thermophilic galactooligosaccharides-producer beta-galactosidase unravels an uncommon oligomeric structure.,Sanita G, Maresca E, Capaldi S, Casillo A, Aulitto M, Donadio F, Pape T, Corsaro MM, Esposito E, Contursi P Int J Biol Macromol. 2026 Apr 13;362:151980. doi: 10.1016/j.ijbiomac.2026.151980. PMID:41985809<ref>PMID:41985809</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 9ta3" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Weizmannia coagulans]]
[[Category: Aulitto M]]
[[Category: Capaldi S]]
[[Category: Contursi P]]
[[Category: Esposito E]]
[[Category: Maresca E]]
[[Category: Sanita G]]