View source for 7qbs


==B12-dependent radical SAM methyltransferase, Mmp10 with [4Fe-4S] cluster, cobalamin, S-adenosyl-L-methionine, and peptide bound.==
<StructureSection load='7qbs' size='340' side='right'caption='[[7qbs]], [[Resolution|resolution]] 2.33&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[7qbs]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Methanosarcina_acetivorans Methanosarcina acetivorans]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7QBS OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7QBS 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]] 2.327&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=COB:CO-METHYLCOBALAMIN'>COB</scene>, <scene name='pdbligand=FE:FE+(III)+ION'>FE</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</scene>, <scene name='pdbligand=SAM:S-ADENOSYLMETHIONINE'>SAM</scene>, <scene name='pdbligand=SF4:IRON/SULFUR+CLUSTER'>SF4</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=7qbs FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7qbs OCA], [https://pdbe.org/7qbs PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7qbs RCSB], [https://www.ebi.ac.uk/pdbsum/7qbs PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7qbs ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/MCRAM_METAC MCRAM_METAC] Radical SAM methyltransferase that is responsible for the C(5)-methylation of 'Arg-285' of the methyl-coenzyme M reductase (MCR) subunit alpha McrA. This post-translational methylation, despite being not essential in vivo, plays a role for the stability and structural integrity of MCR.<ref>PMID:29743535</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
By catalysing the microbial formation of methane, methyl-coenzyme M reductase has a central role in the global levels of this greenhouse gas(1,2). The activity of methyl-coenzyme M reductase is profoundly affected by several unique post-translational modifications(3-6), such as a unique C-methylation reaction catalysed by methanogenesis marker protein 10 (Mmp10), a radical S-adenosyl-L-methionine (SAM) enzyme(7,8). Here we report the spectroscopic investigation and atomic resolution structure of Mmp10 from Methanosarcina acetivorans, a unique B12 (cobalamin)-dependent radical SAM enzyme(9). The structure of Mmp10 reveals a unique enzyme architecture with four metallic centres and critical structural features involved in the control of catalysis. In addition, the structure of the enzyme-substrate complex offers a glimpse into a B12-dependent radical SAM enzyme in a precatalytic state. By combining electron paramagnetic resonance spectroscopy, structural biology and biochemistry, our study illuminates the mechanism by which the emerging superfamily of B12-dependent radical SAM enzymes catalyse chemically challenging alkylation reactions and identifies distinctive active site rearrangements to provide a structural rationale for the dual use of the SAM cofactor for radical and nucleophilic chemistry.

Crystallographic snapshots of a B12-dependent radical SAM methyltransferase.,Fyfe CD, Bernardo-Garcia N, Fradale L, Grimaldi S, Guillot A, Brewee C, Chavas LMG, Legrand P, Benjdia A, Berteau O Nature. 2022 Feb;602(7896):336-342. doi: 10.1038/s41586-021-04355-9. Epub 2022, Feb 2. PMID:35110733<ref>PMID:35110733</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 7qbs" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Methanosarcina acetivorans]]
[[Category: Benjdia A]]
[[Category: Bernardo-Garcia N]]
[[Category: Berteau O]]
[[Category: Chavas LMG]]
[[Category: Fyfe CD]]
[[Category: Legrand P]]