3VJB | pdb_00003vjb

Crystal structure of the human squalene synthase

• PDB DOI: https://doi.org/10.2210/pdb3VJB/pdb

• Classification: TRANSFERASE
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2011-10-14 Released: 2012-04-11 
• Deposition Author(s): Liu, C.I., Jeng, W.Y., Chang, W.J., Wang, A.H.J.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.05 Å
• R-Value Free: 
  0.227 (Depositor), 0.228 (DCC) 
• R-Value Work: 
  0.169 (Depositor), 0.170 (DCC) 
• R-Value Observed: 
  0.172 (Depositor) 

Starting Model: experimental

Literature

Binding modes of zaragozic acid A to human squalene synthase and staphylococcal dehydrosqualene synthase

Liu, C.I., Jeng, W.Y., Chang, W.J., Ko, T.P., Wang, A.H.J.

(2012) J Biological Chem 287: 18750-18757

• PubMed: 22474324 
• DOI: https://doi.org/10.1074/jbc.M112.351254
• Primary Citation Related Structures: 
  3VJ8, 3VJ9, 3VJA, 3VJB, 3VJC, 3VJD, 3VJE


• PubMed Abstract: 
  

  Zaragozic acids (ZAs) belong to a family of fungal metabolites with nanomolar inhibitory activity toward squalene synthase (SQS). The enzyme catalyzes the committed step of sterol synthesis and has attracted attention as a potential target for antilipogenic and antiinfective therapies. Here, we have determined the structure of ZA-A complexed with human SQS. ZA-A binding induces a local conformational change in the substrate binding site, and its C-6 acyl group also extends over to the cofactor binding cavity. In addition, ZA-A effectively inhibits a homologous bacterial enzyme, dehydrosqualene synthase (CrtM), which synthesizes the precursor of staphyloxanthin in Staphylococcus aureus to cope with oxidative stress. Size reduction at Tyr(248) in CrtM further increases the ZA-A binding affinity, and it reveals a similar overall inhibitor binding mode to that of human SQS/ZA-A except for the C-6 acyl group. These structures pave the way for further improving selectivity and development of a new generation of anticholesterolemic and antimicrobial inhibitors.

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Organizational Affiliation: 
• Institute of Biological Chemistry, Academia Sinica, Taipei 115, Taiwan.

Biological Assembly 1  

Global Symmetry: Cyclic - C3  (Explore in 3D)
Global Stoichiometry: Homo 3-mer - A3 

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

Biological Assembly 2  

Global Symmetry: Cyclic - C3  (Explore in 3D)
Global Stoichiometry: Homo 3-mer - A3 

Biological assembly 2 assigned by authors and generated by PISA (software)

Macromolecule Content 

• Total Structure Weight: 236.69 kDa 
• Atom Count: 16,888 
• Modeled Residue Count: 1,973 
• Deposited Residue Count: 2,058 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Squalene synthase	A, B, C, D, E, F	343	Homo sapiens	Mutation(s): 0  Gene Names: FDFT1 EC: 2.5.1.21
UniProt & NIH Common Fund Data Resources
Find proteins for P37268 (Homo sapiens) Explore P37268  Go to UniProtKB:  P37268
PHAROS:  P37268 GTEx:  ENSG00000079459

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.05 Å
• R-Value Free:  0.227 (Depositor), 0.228 (DCC) 
• R-Value Work:  0.169 (Depositor), 0.170 (DCC) 
• R-Value Observed: 0.172 (Depositor) 

Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 85.61	α = 90
b = 153.86	β = 91.68
c = 91.516	γ = 90

Software Package:

Software Name	Purpose
HKL-2000	data collection
MOLREP	phasing
REFMAC	refinement
HKL-2000	data reduction
HKL-2000	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 2012-04-11 
Deposition Author(s): Liu, C.I., Jeng, W.Y., Chang, W.J., Wang, A.H.J.

Revision History  

• Version 1.0: 2012-04-11
  Type: Initial release
  
• Version 1.1: 2013-07-24
  Changes: Database references
• Version 1.2: 2023-11-08
  Changes: Data collection, Database references, Refinement description