View source for 8e18


==Crystal structure of apo TnmK1==
<StructureSection load='8e18' size='340' side='right'caption='[[8e18]], [[Resolution|resolution]] 1.14&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[8e18]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Streptomyces_sp._CB03234 Streptomyces sp. CB03234]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=8E18 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=8E18 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]] 1.14&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=EPE:4-(2-HYDROXYETHYL)-1-PIPERAZINE+ETHANESULFONIC+ACID'>EPE</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=8e18 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=8e18 OCA], [https://pdbe.org/8e18 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=8e18 RCSB], [https://www.ebi.ac.uk/pdbsum/8e18 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=8e18 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/A0A125SA14_9ACTN A0A125SA14_9ACTN] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
First discovered in 1989, the anthraquinone-fused enediynes are a class of DNA-cleaving bacterial natural products composed of a DNA-intercalating anthraquinone moiety and a 10-membered enediyne warhead. However, until recently, there has been a lack of genetically amenable hosts and sequenced biosynthetic gene clusters available for solving the biosynthetic questions surrounding these molecules. Herein, we have identified and biochemically and structurally characterized TnmK1, a member of the alpha/beta-hydrolase fold superfamily responsible for the C-C bond formation linking the anthraquinone moiety and enediyne core together in tiancimycin (TNM) biosynthesis. In doing so, two intermediates, TNM H and TNM I, in anthraquinone-fused enediyne biosynthesis, containing an unprecedented cryptic C16 aldehyde group, were identified. This aldehyde plays a key role in the TnmK1-catalyzed C-C bond formation via a Michael addition, representing the first example of this chemistry for the alpha/beta-hydrolase fold superfamily. Additionally, TNM I shows sub-nanomolar cytotoxicity against selected cancer cell lines, indicating a new mechanism of action compared to previously known anthraquinone-fused enediynes. Together, the findings from this study are expected to impact enzymology, natural product biosynthesis, and future efforts at enediyne discovery and drug development.

Intramolecular C-C Bond Formation Links Anthraquinone and Enediyne Scaffolds in Tiancimycin Biosynthesis.,Gui C, Kalkreuter E, Liu YC, Adhikari A, Teijaro CN, Yang D, Chang C, Shen B J Am Chem Soc. 2022 Oct 24. doi: 10.1021/jacs.2c08957. PMID:36279548<ref>PMID:36279548</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 8e18" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Streptomyces sp. CB03234]]
[[Category: Gui C]]
[[Category: Liu Y-C]]
[[Category: Shen B]]