View source for 9ch2


==Structure of the alpha-N-methyltransferase (SonM) and RiPP precursor (SonA-L63D) heteromeric complex==
<StructureSection load='9ch2' size='340' side='right'caption='[[9ch2]], [[Resolution|resolution]] 2.35&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[9ch2]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Shewanella_oneidensis Shewanella oneidensis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=9CH2 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=9CH2 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]] 2.35&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=SAH:S-ADENOSYL-L-HOMOCYSTEINE'>SAH</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=9ch2 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=9ch2 OCA], [https://pdbe.org/9ch2 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=9ch2 RCSB], [https://www.ebi.ac.uk/pdbsum/9ch2 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=9ch2 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/Q8EGW3_SHEON Q8EGW3_SHEON] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
N-Methylation of the peptide backbone confers pharmacologically beneficial characteristics to peptides that include greater membrane permeability and resistance to proteolytic degradation. The borosin family of ribosomally synthesized and post-translationally modified peptides offer a post-translational route to install amide backbone alpha-N-methylations. Previous work has elucidated the substrate scope and engineering potential of two examples of type I borosins, which feature autocatalytic precursors that encode N-methyltransferases that methylate their own C-termini in trans. We recently reported the first discrete N-methyltransferase and precursor peptide from Shewanella oneidensis MR-1, a minimally iterative, type IV borosin that allowed the first detailed kinetic analyses of borosin N-methyltransferases. Herein, we characterize the substrate scope and resilient regiospecificity of this discrete N-methyltransferase by comparison of relative rates and methylation patterns of over 40 precursor peptide variants along with structure analyses of nine enzyme-substrate complexes. Sequences critical to methylation are identified and demonstrated in assaying minimal peptide substrates and non-native peptide sequences for assessment of secondary structure requirements and engineering potential. This work grants understanding towards the mechanism of substrate recognition and iterative activity by discrete borosin N-methyltransferases.

alpha-N-Methyltransferase regiospecificity is mediated by proximal, redundant enzyme-substrate interactions.,Crone KK, Labonte JW, Elias MH, Freeman MF Protein Sci. 2025 Feb;34(2):e70021. doi: 10.1002/pro.70021. PMID:39840790<ref>PMID:39840790</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 9ch2" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Shewanella oneidensis]]
[[Category: Crone KK]]
[[Category: Elias M]]
[[Category: Freeman MF]]
[[Category: Labonte JW]]