4QNW

Crystal structure of EasA, an old yellow enzyme from Aspergillus fumigatus

• PDB DOI: https://doi.org/10.2210/pdb4QNW/pdb

• Classification: OXIDOREDUCTASE
• Organism(s): Aspergillus fumigatus Af293
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2014-06-18 Released: 2014-10-22 
• Deposition Author(s): Lamb, A.L.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.80 Å
• R-Value Free: 0.221 
• R-Value Work: 0.178 
• R-Value Observed: 0.182 

Literature

Structure of an Aspergillus fumigatus old yellow enzyme (EasA) involved in ergot alkaloid biosynthesis.

Chilton, A.S., Ellis, A.L., Lamb, A.L.

(2014) Acta Crystallogr Sect F Struct Biol Cryst Commun 70: 1328-1332

• PubMed: 25286934 
• DOI: https://doi.org/10.1107/S2053230X14018962
• Primary Citation of Related Structures:  
  4QNW


• PubMed Abstract: 
  

  The Aspergillus fumigatus old yellow enzyme (OYE) EasA reduces chanoclavine-I aldehyde to dihydrochanoclavine aldehyde and works in conjunction with festuclavine synthase at the branchpoint for ergot alkaloid pathways. The crystal structure of the FMN-loaded EasA was determined to 1.8 Å resolution. The active-site amino acids of OYE are conserved, supporting a similar mechanism for reduction of the α/β-unsaturated aldehyde. The C-terminal tail of one monomer packs into the active site of a monomer in the next asymmetric unit, which is most likely to be a crystallization artifact and not a mechanism of self-regulation.

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Organizational Affiliation: 

Molecular Biosciences, University of Kansas, 1200 Sunnyside Avenue, Lawrence, KS 66045, USA.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 44.91 kDa 
• Atom Count: 3,212 
• Modelled Residue Count: 369 
• Deposited Residue Count: 392 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Chanoclavine-I aldehyde reductase	A	392	Aspergillus fumigatus Af293	Mutation(s): 0  Gene Names: AFUA_2G17960, EasA, fgaOx3 EC: 1.3.1.100
UniProt
Find proteins for Q4WZ70 (Aspergillus fumigatus (strain ATCC MYA-4609 / CBS 101355 / FGSC A1100 / Af293)) Explore Q4WZ70  Go to UniProtKB:  Q4WZ70

Small Molecules

Ligands 3 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
FMN	B [auth A]	FLAVIN MONONUCLEOTIDE C17 H21 N4 O9 P FVTCRASFADXXNN-SCRDCRAPSA-N
SO4	C [auth A], D [auth A], E [auth A], F [auth A]	SULFATE ION O4 S QAOWNCQODCNURD-UHFFFAOYSA-L
GOL	G [auth A]	GLYCEROL C3 H8 O3 PEDCQBHIVMGVHV-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.80 Å
• R-Value Free: 0.221 
• R-Value Work: 0.178 
• R-Value Observed: 0.182 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 62.456	α = 90
b = 65.913	β = 90
c = 115.219	γ = 90

Software Package:

Software Name	Purpose
Blu-Ice	data collection
PHASER	phasing
REFMAC	refinement
XDS	data reduction
XDS	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 2014-10-22 
Deposition Author(s): Lamb, A.L.

Revision History  

• Version 1.0: 2014-10-22
  Type: Initial release
  
• Version 1.1: 2023-09-20
  Changes: Data collection, Database references, Derived calculations, Refinement description