View source for 9m35


==E. coli MaeB acetyl-CoA bound form ME domain dimer==
<StructureSection load='9m35' size='340' side='right'caption='[[9m35]], [[Resolution|resolution]] 2.39&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[9m35]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli_K-12 Escherichia coli K-12]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=9M35 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=9M35 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]] 2.39&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=NAP:NADP+NICOTINAMIDE-ADENINE-DINUCLEOTIDE+PHOSPHATE'>NAP</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=9m35 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=9m35 OCA], [https://pdbe.org/9m35 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=9m35 RCSB], [https://www.ebi.ac.uk/pdbsum/9m35 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=9m35 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/MAO2_ECOLI MAO2_ECOLI] Catalyzes the decarboxylation of malate to pyruvate (PubMed:17557829). In vitro, shows malolactic enzyme activity in the presence of NADPH. However, it is unlikely that this activity is of relevance in E.coli, which produces little NADPH (PubMed:33824210).<ref>PMID:17557829</ref> <ref>PMID:33824210</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Malic enzymes (MEs) function as the bypass enzyme in the Krebs cycle and have attracted attention in a wide range of scientific and industrial fields. In contrast to eukaryotic MEs, there is currently a lack of understanding of the structure-function relationships of prokaryotic MEs. Especially, little is known about an allosteric inhibition mechanism by an effector ligand in multi-domain MEs called hybrid-type MEs. Many bacterial hybrid-type MEs are inhibited by acetyl-CoA; however, the proposed acetyl-CoA binding site is not conserved. Here, we determined crystal and cryo-EM structures of hybrid-type MEs from Escherichia coli (EcMaeB) and Bdellovibrio bacteriovorus including complexes with acetyl-CoA. They reveal that these MaeBs have totally different acetyl-CoA binding sites and show different overall structural changes. However, the binding acetyl-CoA molecules induce identical movements of several alpha helices near the ligand both in EcMaeB and BbMaeB. Enzymatic assays proved that residues at the acetyl-CoA binding site are needed for inhibition. Phylogenetic analysis uncovered that EcMaeB and BbMaeB are classified into different clades of hybrid-type MEs and that the amino acid residues at the acetyl-CoA binding sites in different clades have evolved exclusively from each other. These results not only provide insights into bacterial MEs but also expand our knowledge about allosteric regulation in enzymes.

Divergent acetyl-CoA binding modes mediate allosteric inhibition of bacterial hybrid-type malic enzymes.,Sassa M, Yamato H, Tanino H, Fukuda Y, Inoue T J Biol Chem. 2025 Nov 4;301(12):110887. doi: 10.1016/j.jbc.2025.110887. PMID:41197718<ref>PMID:41197718</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 9m35" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Escherichia coli K-12]]
[[Category: Large Structures]]
[[Category: Fukuda Y]]
[[Category: Inoue T]]
[[Category: Sassa M]]
[[Category: Tanino H]]
[[Category: Yamato H]]