5y7r

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Revision as of 08:24, 22 February 2018

Quaternary complex of AsqJ-Fe3+-2OG-cyclopeptin

Structural highlights

5y7r is a 1 chain structure with sequence from Aspergillus nidulans. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:	, ,
Gene:	asqJ, AN9227 (Aspergillus nidulans)
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[ASQJ_EMENI] Iron/alpha-ketoglutarate-dependent dioxygenase; part of the gene cluster that mediates the biosynthesis of the aspoquinolone mycotoxins (PubMed:25251934, PubMed:26553478). The first stage is catalyzed by the nonribosomal pepdide synthetase asqK that condenses anthranilic acid and O-methyl-L-tyrosine to produce 4'-methoxycyclopeptin (PubMed:25251934). AsqK is also able to use anthranilic acid and L-phenylalanine as substrates to produce cyclopeptin, but at a tenfold lower rate (PubMed:25251934). 4'-methoxycyclopeptin is then converted to 4'-methoxydehydrocyclopeptin by the ketoglutarate-dependent dioxygenase asqJ through dehydrogenation to form a double bond between C-alpha and C-beta of the O-methyltyrosine side chain (PubMed:25251934, PubMed:26553478). AsqJ also converts its first product 4'-methoxydehydrocyclopeptin to 4'-methoxycyclopenin (PubMed:25251934). AsqJ is a very unique dioxygenase which is capable of catalyzing radical-mediated dehydrogenation and epoxidation reactions sequentially on a 6,7-benzo-diazepinedione substrate in the 4'-methoxyviridicatin biosynthetic pathway (PubMed:25251934). The following conversion of 4'-methoxycyclopenin into 4'-methoxyviridicatin proceeds non-enzymatically (PubMed:25251934). AsqJ is also capable of converting cyclopeptin into dehydrocyclopeptin and cyclopenin in a sequential fashion (PubMed:25251934). Cyclopenin can be converted into viridicatin non-enzymatically (PubMed:25251934). 4'-methoxyviridicatin likely acts as a precursor of quinolone natural products, such as aspoquinolones, peniprequinolones, penigequinolones, and yaequinolones (PubMed:25251934). Further characterization of the remaining genes in the cluster has still to be done to determine the exact identity of quinolone products this cluster is responsible for biosynthesizing (PubMed:25251934).^[1] ^[2]

Publication Abstract from PubMed

AsqJ, an iron(II)- and 2-oxoglutarate-dependent enzyme found in viridicatin-type alkaloid biosynthetic pathways, catalyzes sequential desaturation and epoxidation to produce cyclopenins. Crystal structures of AsqJ bound to cyclopeptin and its C3 epimer are reported. Meanwhile, a detailed mechanistic study was carried out to decipher the desaturation mechanism. These findings suggest that a pathway involving hydrogen atom abstraction at the C10 position of the substrate by a short-lived Fe(IV) -oxo species and the subsequent formation of a carbocation or a hydroxylated intermediate is preferred during AsqJ-catalyzed desaturation.

Insights into the Desaturation of Cyclopeptin and its C3 Epimer Catalyzed by a non-Heme Iron Enzyme: Structural Characterization and Mechanism Elucidation.,Liao HJ, Li J, Huang JL, Davidson M, Kurnikov I, Lin TS, Lee JL, Kurnikova M, Guo Y, Chan NL, Chang WC Angew Chem Int Ed Engl. 2018 Jan 3. doi: 10.1002/anie.201710567. PMID:29314482^[3]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Ishikawa N, Tanaka H, Koyama F, Noguchi H, Wang CC, Hotta K, Watanabe K. Non-heme dioxygenase catalyzes atypical oxidations of 6,7-bicyclic systems to form the 6,6-quinolone core of viridicatin-type fungal alkaloids. Angew Chem Int Ed Engl. 2014 Nov 17;53(47):12880-4. doi: 10.1002/anie.201407920. , Epub 2014 Sep 22. PMID:25251934 doi:http://dx.doi.org/10.1002/anie.201407920
↑ Brauer A, Beck P, Hintermann L, Groll M. Structure of the Dioxygenase AsqJ: Mechanistic Insights into a One-Pot Multistep Quinolone Antibiotic Biosynthesis. Angew Chem Int Ed Engl. 2015 Nov 10. doi: 10.1002/anie.201507835. PMID:26553478 doi:http://dx.doi.org/10.1002/anie.201507835
↑ Liao HJ, Li J, Huang JL, Davidson M, Kurnikov I, Lin TS, Lee JL, Kurnikova M, Guo Y, Chan NL, Chang WC. Insights into the Desaturation of Cyclopeptin and its C3 Epimer Catalyzed by a non-Heme Iron Enzyme: Structural Characterization and Mechanism Elucidation. Angew Chem Int Ed Engl. 2018 Jan 3. doi: 10.1002/anie.201710567. PMID:29314482 doi:http://dx.doi.org/10.1002/anie.201710567

1 Structural highlights
2 Function
3 Publication Abstract from PubMed
4 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/5y7r"

Categories: Aspergillus nidulans | Liao, H J | Lin, T S | Initial step for olefination | Oxidoreductase

@@ Line 3: / Line 3: @@
 <StructureSection load='5y7r' size='340' side='right' caption='[[5y7r]], [[Resolution|resolution]] 1.96&Aring;' scene=''>
 == Structural highlights ==
-<table><tr><td colspan='2'>[[5y7r]] is a 1 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5Y7R OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5Y7R FirstGlance]. <br>
+<table><tr><td colspan='2'>[[5y7r]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Aspergillus_nidulans Aspergillus nidulans]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5Y7R OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5Y7R FirstGlance]. <br>
 </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=58K:CYCLOPEPTIN'>58K</scene>, <scene name='pdbligand=AKG:2-OXOGLUTARIC+ACID'>AKG</scene>, <scene name='pdbligand=FE:FE+(III)+ION'>FE</scene></td></tr>
+<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">asqJ, AN9227 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=227321 Aspergillus nidulans])</td></tr>
 <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5y7r FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5y7r OCA], [http://pdbe.org/5y7r PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5y7r RCSB], [http://www.ebi.ac.uk/pdbsum/5y7r PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=5y7r ProSAT]</span></td></tr>
 </table>
@@ Line 22: / Line 23: @@
 __TOC__
 </StructureSection>
+[[Category: Aspergillus nidulans]]
 [[Category: Liao, H J]]
 [[Category: Lin, T S]]
 [[Category: Initial step for olefination]]
 [[Category: Oxidoreductase]]

5y7r

From Proteopedia

Revision as of 08:24, 22 February 2018

Quaternary complex of AsqJ-Fe3+-2OG-cyclopeptin

Structural highlights

Function

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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