View source for 7wzv


==The structure of a Twitch Radical SAM Dehydrogenase SpeY==
<StructureSection load='7wzv' size='340' side='right'caption='[[7wzv]], [[Resolution|resolution]] 1.90&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[7wzv]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Streptomyces_spectabilis Streptomyces spectabilis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7WZV OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7WZV 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]] 1.899313&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=7P8:(1~{S},2~{R},4~{S},5~{R})-2,4-bis(methylamino)-6-[(2~{S},3~{R},4~{S},6~{R})-6-methyl-3,4-bis(oxidanyl)oxan-2-yl]oxy-cyclohexane-1,3,5-triol'>7P8</scene>, <scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=EDO:1,2-ETHANEDIOL'>EDO</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</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>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</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=7wzv FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7wzv OCA], [https://pdbe.org/7wzv PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7wzv RCSB], [https://www.ebi.ac.uk/pdbsum/7wzv PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7wzv ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/A8WEZ7_STRST A8WEZ7_STRST] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Spectinomycin is a dioxane-bridged, tricyclic aminoglycoside produced by Streptomyces spectabilis ATCC 27741. While the spe biosynthetic gene cluster for spectinomycin has been reported, the chemistry underlying construction of the dioxane ring is unknown. The twitch radical SAM enzyme SpeY from the spe cluster is shown here to catalyze dehydrogenation of the C2' alcohol of (2'R,3'S)-tetrahydrospectinomycin to yield (3'S)-dihydrospectinomycin as a likely biosynthetic intermediate. This reaction is radical-mediated and initiated via H atom abstraction from C2' of the substrate by the 5'-deoxyadenosyl radical equivalent generated upon reductive cleavage of SAM. Crystallographic analysis of the ternary Michaelis complex places serine-183 adjacent to C2' of the bound substrate opposite C5' of SAM. Mutation of this residue to cysteine converts SpeY to the corresponding C2' epimerase mirroring the opposite phenomenon observed in the homologous twitch radical SAM epimerase HygY from the hygromycin B biosynthetic pathway. Phylogenetic analysis suggests a relatively recent evolutionary branching of putative twitch radical SAM epimerases bearing homologous cysteine residues to generate the SpeY clade of enzymes.

Dioxane Bridge Formation during the Biosynthesis of Spectinomycin Involves a Twitch Radical S-Adenosyl Methionine Dehydrogenase That May Have Evolved from an Epimerase.,Zhang J, Hou X, Chen Z, Ko Y, Ruszczycky MW, Chen Y, Zhou J, Liu HW J Am Chem Soc. 2022 Jun 8;144(22):9910-9919. doi: 10.1021/jacs.2c02676. Epub 2022 , May 27. PMID:35622017<ref>PMID:35622017</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 7wzv" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Streptomyces spectabilis]]
[[Category: Hou XL]]
[[Category: Zhou JH]]