4J2V

Crystal Structure of Equine Serum Albumin in complex with 3,5-diiodosalicylic acid

• PDB DOI: https://doi.org/10.2210/pdb4J2V/pdb

• Classification: TRANSPORT PROTEIN
• Organism(s): Equus caballus
• Mutation(s): No 


• Deposited: 2013-02-05 Released: 2013-07-24 
• Deposition Author(s): Sekula, B., Bujacz, A., Zielinski, K., Bujacz, G.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.12 Å
• R-Value Free: 0.238 
• R-Value Work: 0.181 
• R-Value Observed: 0.183 

Starting Model: experimental

Literature

Crystallographic studies of the complexes of bovine and equine serum albumin with 3,5-diiodosalicylic acid.

Sekula, B., Zielinski, K., Bujacz, A.

(2013) Int J Biol Macromol 60C: 316-324

• PubMed: 23769932 
• DOI: https://doi.org/10.1016/j.ijbiomac.2013.06.004
• Primary Citation of Related Structures:  
  4J2V, 4JK4


• PubMed Abstract: 
  

  Due to their extraordinary binding properties, serum albumins are the main transporters of many small molecules in the circulatory system. Although all mammalian serum albumins exhibit quite high sequence similarity, their binding abilities are not the same. Until now, only human serum albumin (HSA) was subjected to extensive structural studies in complexes with various ligands. Here we present two crystal structures of the complexes of equine and bovine serum albumins with 3,5-diiodosalicylic acid (DIS), at resolutions 2.12 Å and 2.65 Å, respectively, and analyze interactions of the DIS ligand with both macromolecules. We highlight the differences in distribution of DIS binding sites between the bovine and equine serum albumins and compare results with the HSA binding ability of DIS and other structurally similar ligands.

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Organizational Affiliation: 

Institute of Technical Biochemistry, Lodz University of Technology, Stefanowskiego 4/10, 90-924 Lodz, Poland.

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: 68.56 kDa 
• Atom Count: 4,986 
• Modelled Residue Count: 581 
• Deposited Residue Count: 583 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Serum albumin	A	583	Equus caballus	Mutation(s): 0
UniProt
Find proteins for P35747 (Equus caballus) Explore P35747  Go to UniProtKB:  P35747

Small Molecules

Ligands 4 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
DIU	B [auth A], C [auth A], D [auth A], E [auth A]	2-HYDROXY-3,5-DIIODO-BENZOIC ACID C7 H4 I2 O3 DHZVWQPHNWDCFS-UHFFFAOYSA-N
MLI	F [auth A], G [auth A], H [auth A], I [auth A], J [auth A], K [auth A], L [auth A]	MALONATE ION C3 H2 O4 OFOBLEOULBTSOW-UHFFFAOYSA-L
ACT	U [auth A]	ACETATE ION C2 H3 O2 QTBSBXVTEAMEQO-UHFFFAOYSA-M
FMT	M [auth A], N [auth A], O [auth A], P [auth A], Q [auth A], R [auth A], S [auth A], T [auth A]	FORMIC ACID C H2 O2 BDAGIHXWWSANSR-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.12 Å
• R-Value Free: 0.238 
• R-Value Work: 0.181 
• R-Value Observed: 0.183 
• Space Group: P 6₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 88.88	α = 90
b = 88.88	β = 90
c = 134.34	γ = 120

Software Package:

Software Name	Purpose
PHENIX	refinement
REFMAC	refinement
XDS	data scaling
XDS	data reduction
REFMAC	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2013-07-24 
Deposition Author(s): Sekula, B., Bujacz, A., Zielinski, K., Bujacz, G.

Revision History  

• Version 1.0: 2013-07-24
  Type: Initial release
  
• Version 1.1: 2019-07-17
  Changes: Data collection, Refinement description
• Version 1.2: 2023-09-20
  Changes: Data collection, Database references, Derived calculations, Refinement description
• Version 1.3: 2024-11-06
  Changes: Structure summary