6OXH

X-ray crystal structure of His-tagged Y140F FtmOx1 bound to Fe(II) and 2-oxoglutarate


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.92 Å
  • R-Value Free: 0.258 
  • R-Value Work: 0.230 
  • R-Value Observed: 0.231 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Hydrogen Donation but not Abstraction by a Tyrosine (Y68) during Endoperoxide Installation by Verruculogen Synthase (FtmOx1).

Dunham, N.P.Del Rio Pantoja, J.M.Zhang, B.Rajakovich, L.J.Allen, B.D.Krebs, C.Boal, A.K.Bollinger Jr., J.M.

(2019) J Am Chem Soc 141: 9964-9979

  • DOI: 10.1021/jacs.9b03567
  • Primary Citation of Related Structures:  
    6OXH, 6OXJ

  • PubMed Abstract: 
  • Hydrogen-atom transfer (HAT) from a substrate carbon to an iron(IV)-oxo (ferryl) intermediate initiates a diverse array of enzymatic transformations. For outcomes other than hydroxylation, coupling of the resultant carbon radical and hydroxo ligand (oxygen rebound) must generally be averted ...

    Hydrogen-atom transfer (HAT) from a substrate carbon to an iron(IV)-oxo (ferryl) intermediate initiates a diverse array of enzymatic transformations. For outcomes other than hydroxylation, coupling of the resultant carbon radical and hydroxo ligand (oxygen rebound) must generally be averted. A recent study of FtmOx1, a fungal iron(II)- and 2-(oxo)glutarate-dependent oxygenase that installs the endoperoxide of verruculogen by adding O 2 between carbons 21 and 27 of fumitremorgin B, posited that tyrosine (Tyr or Y) 224 serves as HAT intermediary to separate the C21 radical (C21•) and Fe(III)-OH HAT products and prevent rebound. Our reinvestigation of the FtmOx1 mechanism revealed, instead, direct HAT from C21 to the ferryl complex and surprisingly competitive rebound. The C21-hydroxylated (rebound) product, which undergoes deprenylation, predominates when low [O 2 ] slows C21•-O 2 coupling in the next step of the endoperoxidation pathway. This pathway culminates with addition of the C21-O-O• peroxyl adduct to olefinic C27 followed by HAT to the C26• from a Tyr. The last step results in sequential accumulation of Tyr radicals, which are suppressed without detriment to turnover by inclusion of the reductant, ascorbate. Replacement of each of four candidates for the proximal C26 H• donor (including Y224) with phenylalanine (F) revealed that only the Y68F variant (i) fails to accumulate the first Tyr• and (ii) makes an altered major product, identifying Y68 as the donor. The implied proximities of C21 to the iron cofactor and C26 to Y68 support a new docking model of the enzyme-substrate complex that is consistent with all available data.


    Organizational Affiliation

    Department of Biochemistry, University of Bayreuth, Universitätsstr. 30, 95447 Bayreuth, Germany.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Verruculogen synthaseA, B313Aspergillus fumigatus Af293Mutation(s): 1 
Gene Names: ftmOx1ftmFAFUA_8G00230
EC: 1.14.11.38
UniProt
Find proteins for Q4WAW9 (Neosartorya fumigata (strain ATCC MYA-4609 / Af293 / CBS 101355 / FGSC A1100))
Explore Q4WAW9 
Go to UniProtKB:  Q4WAW9
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
AKG
Query on AKG

Download Ideal Coordinates CCD File 
D [auth A], F [auth B]2-OXOGLUTARIC ACID
C5 H6 O5
KPGXRSRHYNQIFN-UHFFFAOYSA-N
 Ligand Interaction
FE2
Query on FE2

Download Ideal Coordinates CCD File 
C [auth A], E [auth B]FE (II) ION
Fe
CWYNVVGOOAEACU-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.92 Å
  • R-Value Free: 0.258 
  • R-Value Work: 0.230 
  • R-Value Observed: 0.231 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 73.512α = 90
b = 79.362β = 90
c = 91.511γ = 90
Software Package:
Software NamePurpose
HKL-2000data reduction
SCALEPACKdata scaling
REFMACrefinement
PDB_EXTRACTdata extraction
PHASERphasing

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)United StatesGM119707

Revision History  (Full details and data files)

  • Version 1.0: 2019-07-03
    Type: Initial release
  • Version 1.1: 2019-07-10
    Changes: Data collection, Database references
  • Version 1.2: 2020-01-01
    Changes: Author supporting evidence