4TPO

High-resolution structure of TxtE with bound tryptophan substrate


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.23 Å
  • R-Value Free: 0.160 
  • R-Value Work: 0.138 
  • R-Value Observed: 0.139 

wwPDB Validation   3D Report Full Report


Ligand Structure Quality Assessment 


This is version 1.5 of the entry. See complete history


Literature

Structural, Functional, and Spectroscopic Characterization of the Substrate Scope of the Novel Nitrating Cytochrome P450 TxtE.

Dodani, S.C.Cahn, J.K.Heinisch, T.Brinkmann-Chen, S.McIntosh, J.A.Arnold, F.H.

(2014) Chembiochem 15: 2259-2267

  • DOI: https://doi.org/10.1002/cbic.201402241
  • Primary Citation of Related Structures:  
    4TPN, 4TPO

  • PubMed Abstract: 

    A novel cytochrome P450 enzyme, TxtE, was recently shown to catalyze the direct aromatic nitration of L-tryptophan. This unique chemistry inspired us to ask whether TxtE could serve as a platform for engineering new nitration biocatalysts to replace current harsh synthetic methods. As a first step toward this goal, and to better understand the wild-type enzyme, we obtained high-resolution structures of TxtE in its substrate-free and substrate-bound forms. We also screened a library of substrate analogues for spectroscopic indicators of binding and for production of nitrated products. From these results, we found that the wild-type enzyme accepts moderate decoration of the indole ring, but the amino acid moiety is crucial for binding and correct positioning of the substrate and therefore less amenable to modification. A nitrogen atom is essential for catalysis, and a carbonyl must be present to recruit the αB'1 helix of the protein to seal the binding pocket.


  • Organizational Affiliation

    Division of Chemistry and Chemical Engineering, California Institute of Technology, MC 210-41 Pasadena, CA (USA).


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Putative P450-like protein407Streptomyces scabiei 87.22Mutation(s): 0 
Gene Names: SCAB_31831
UniProt
Find proteins for C9ZDC6 (Streptomyces scabiei (strain 87.22))
Explore C9ZDC6 
Go to UniProtKB:  C9ZDC6
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupC9ZDC6
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 4 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
HEM
Query on HEM

Download Ideal Coordinates CCD File 
B [auth A]PROTOPORPHYRIN IX CONTAINING FE
C34 H32 Fe N4 O4
KABFMIBPWCXCRK-RGGAHWMASA-L
TRP
Query on TRP

Download Ideal Coordinates CCD File 
F [auth A]TRYPTOPHAN
C11 H12 N2 O2
QIVBCDIJIAJPQS-VIFPVBQESA-N
SO4
Query on SO4

Download Ideal Coordinates CCD File 
G [auth A],
H [auth A],
I [auth A],
J [auth A]
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
GOL
Query on GOL

Download Ideal Coordinates CCD File 
C [auth A],
D [auth A],
E [auth A]
GLYCEROL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
Binding Affinity Annotations 
IDSourceBinding Affinity
TRP Binding MOAD:  4TPO Kd: 3.90e+4 (nM) from 1 assay(s)
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.23 Å
  • R-Value Free: 0.160 
  • R-Value Work: 0.138 
  • R-Value Observed: 0.139 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 65.832α = 90
b = 79.657β = 90
c = 112.554γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
SCALAdata scaling
PDB_EXTRACTdata extraction

Structure Validation

View Full Validation Report



Ligand Structure Quality Assessment 


Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2014-09-10
    Type: Initial release
  • Version 1.1: 2014-09-17
    Changes: Database references
  • Version 1.2: 2014-10-15
    Changes: Database references
  • Version 1.3: 2015-02-04
    Changes: Derived calculations
  • Version 1.4: 2017-11-22
    Changes: Derived calculations, Other, Refinement description, Source and taxonomy
  • Version 1.5: 2023-12-27
    Changes: Data collection, Database references, Refinement description