The complex structure of TcSQS with ligand, FSPP

Experimental Data Snapshot

  • Resolution: 2.24 Å
  • R-Value Free: 0.259 
  • R-Value Work: 0.215 

wwPDB Validation   3D Report Full Report

This is version 1.1 of the entry. See complete history


Squalene synthase as a target for Chagas disease therapeutics.

Shang, N.Li, Q.Ko, T.P.Chan, H.C.Li, J.Zheng, Y.Huang, C.H.Ren, F.Chen, C.C.Zhu, Z.Galizzi, M.Li, Z.H.Rodrigues-Poveda, C.A.Gonzalez-Pacanowska, D.Veiga-Santos, P.de Carvalho, T.M.de Souza, W.Urbina, J.A.Wang, A.H.Docampo, R.Li, K.Liu, Y.L.Oldfield, E.Guo, R.T.

(2014) PLoS Pathog 10: e1004114-e1004114

  • DOI: https://doi.org/10.1371/journal.ppat.1004114
  • Primary Citation of Related Structures:  
    3WC9, 3WCA, 3WCB, 3WCC, 3WCD, 3WCE, 3WCF, 3WCG, 3WCH, 3WCI, 3WCJ, 3WCL, 3WCM

  • PubMed Abstract: 

    Trypanosomatid parasites are the causative agents of many neglected tropical diseases and there is currently considerable interest in targeting endogenous sterol biosynthesis in these organisms as a route to the development of novel anti-infective drugs. Here, we report the first x-ray crystallographic structures of the enzyme squalene synthase (SQS) from a trypanosomatid parasite, Trypanosoma cruzi, the causative agent of Chagas disease. We obtained five structures of T. cruzi SQS and eight structures of human SQS with four classes of inhibitors: the substrate-analog S-thiolo-farnesyl diphosphate, the quinuclidines E5700 and ER119884, several lipophilic bisphosphonates, and the thiocyanate WC-9, with the structures of the two very potent quinuclidines suggesting strategies for selective inhibitor development. We also show that the lipophilic bisphosphonates have low nM activity against T. cruzi and inhibit endogenous sterol biosynthesis and that E5700 acts synergistically with the azole drug, posaconazole. The determination of the structures of trypanosomatid and human SQS enzymes with a diverse set of inhibitors active in cells provides insights into SQS inhibition, of interest in the context of the development of drugs against Chagas disease.

  • Organizational Affiliation

    Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Farnesyltransferase, putative
A, B, C, D
365Trypanosoma cruzi strain CL BrenerMutation(s): 1 
Gene Names: Tc00.1047053508369.20
Find proteins for Q4CWB4 (Trypanosoma cruzi (strain CL Brener))
Explore Q4CWB4 
Go to UniProtKB:  Q4CWB4
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ4CWB4
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Resolution: 2.24 Å
  • R-Value Free: 0.259 
  • R-Value Work: 0.215 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 79.129α = 90
b = 132.869β = 90
c = 141.915γ = 90
Software Package:
Software NamePurpose
HKL-2000data collection
HKL-2000data reduction
HKL-2000data scaling

Structure Validation

View Full Validation Report

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2014-06-18
    Type: Initial release
  • Version 1.1: 2023-11-08
    Changes: Data collection, Database references, Derived calculations, Refinement description