1UH5

Crystal Structure of Enoyl-ACP Reductase with Triclosan at 2.2angstroms

• PDB DOI: https://doi.org/10.2210/pdb1UH5/pdb

• Classification: OXIDOREDUCTASE
• Organism(s): Plasmodium falciparum
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2003-06-24 Released: 2004-09-28 
• Deposition Author(s): Swarnamukhi, P.L., Kapoor, M., Surolia, N., Surolia, A., Suguna, K.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.20 Å
• R-Value Free: 0.211 
• R-Value Work: 0.180 
• R-Value Observed: 0.180 

Starting Model: experimental

Literature

Structural basis for the variation in triclosan affinity to enoyl reductases.

Pidugu, L.S., Kapoor, M., Surolia, N., Surolia, A., Suguna, K.

(2004) J Mol Biol 343: 147-155

• PubMed: 15381426 
• DOI: https://doi.org/10.1016/j.jmb.2004.08.033
• Primary Citation of Related Structures:  
  1UH5, 1V35


• PubMed Abstract: 
  

  Bacteria synthesize fatty acids in a dissociated type pathway different from that in humans. Enoyl acyl carrier protein reductase, which catalyzes the final step of fatty acid elongation, has been validated as a potential anti-microbial drug target. Triclosan is known to inhibit this enzyme effectively. Precise characterization of the mode of triclosan binding is required to develop highly specific inhibitors. With this in view, interactions between triclosan, the cofactor NADH/NAD+ and the enzyme from five different species, one plant and four of microbial origin, have been examined in the available crystal structures. A comparison of these structures shows major structural differences at the substrate/inhibitor/cofactor-binding loop. The analysis reveals that the conformation of this flexible loop and the binding affinities of triclosan to each of these enzymes are strongly correlated.

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Organizational Affiliation: 

Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012.

Biological Assembly 1  

Global Symmetry: Dihedral - D2  (Explore in 3D)
Global Stoichiometry: Homo 4-mer - A4 

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

Macromolecule Content

• Total Structure Weight: 76.39 kDa 
• Atom Count: 4,607 
• Modelled Residue Count: 574 
• Deposited Residue Count: 658 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
enoyl-ACP reductase	A, B	329	Plasmodium falciparum	Mutation(s): 0  Gene Names: FabI EC: 1.3.1.9
UniProt
Find proteins for Q9BJJ9 (Plasmodium falciparum) Explore Q9BJJ9  Go to UniProtKB:  Q9BJJ9

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
NAD	D [auth A], F [auth B]	NICOTINAMIDE-ADENINE-DINUCLEOTIDE C21 H27 N7 O14 P2 BAWFJGJZGIEFAR-NNYOXOHSSA-N
TCL	C [auth A], E [auth B]	TRICLOSAN C12 H7 Cl3 O2 XEFQLINVKFYRCS-UHFFFAOYSA-N

Binding Affinity Annotations
ID	Source	Binding Affinity
TCL	BindingDB:  1UH5	Ki: min: 1.90e-3, max: 13.72 (nM) from 11 assay(s)
		IC50: min: 49, max: 200 (nM) from 6 assay(s)

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.20 Å
• R-Value Free: 0.211 
• R-Value Work: 0.180 
• R-Value Observed: 0.180 
• Space Group: P 4₃ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 133.016	α = 90
b = 133.016	β = 90
c = 83.659	γ = 90

Software Package:

Software Name	Purpose
CNS	refinement
DENZO	data reduction
SCALEPACK	data scaling
AMoRE	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2004-09-28 
Deposition Author(s): Swarnamukhi, P.L., Kapoor, M., Surolia, N., Surolia, A., Suguna, K.

Revision History  

• Version 1.0: 2004-09-28
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Derived calculations, Version format compliance
• Version 1.3: 2017-11-29
  Changes: Derived calculations
• Version 1.4: 2023-10-25
  Changes: Data collection, Database references, Derived calculations, Refinement description