7VJT | pdb_00007vjt

Crystal Structure of Mtb Pks13-TE in complex with inhibitor coumestan derivative 8


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.94 Å
  • R-Value Free: 
    0.224 (Depositor), 0.230 (DCC) 
  • R-Value Work: 
    0.185 (Depositor), 0.190 (DCC) 
  • R-Value Observed: 
    0.187 (Depositor) 

Starting Model: experimental
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This is version 1.3 of the entry. See complete history


Literature

Structure-Based Optimization of Coumestan Derivatives as Polyketide Synthase 13-Thioesterase(Pks13-TE) Inhibitors with Improved hERG Profiles for Mycobacterium tuberculosis Treatment.

Zhang, W.Lun, S.Wang, S.S.Cai, Y.P.Yang, F.Tang, J.Bishai, W.R.Yu, L.F.

(2022) J Med Chem 65: 13240-13252

  • DOI: https://doi.org/10.1021/acs.jmedchem.2c01064
  • Primary Citation of Related Structures:  
    7VJT

  • PubMed Abstract: 

    Pks13 was identified as a key enzyme involved in the final step of mycolic acid biosynthesis. We previously identified antitubercular coumestans that targeted Pks13-TE, and these compounds exhibited high potency both in vitro and in vivo. However, lead compound 8 presented potential safety concerns because it inhibits the hERG potassium channel in electrophysiology patch-clamp assays (IC 50 = 0.52 μM). By comparing the Pks13-TE-compound 8 complex and the ligand-binding pocket of the hERG ion channel, fluoro-substituted and oxazine-containing coumestans were designed and synthesized. Fluoro-substituted compound 23 and oxazine-containing coumestan 32 showed excellent antitubercular activity against both drug-susceptible and drug-resistant Mtb strains (MIC = 0.0039-0.0078 μg/mL) and exhibited limited hERG inhibition (IC 50 ≥ 25 μM). Moreover, 32 exhibited improved metabolic stability relative to parent compound 8 while showing favorable bioavailability in mouse models via serum inhibition titration assays.


  • Organizational Affiliation
    • Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, China.

Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Polyketide synthase Pks13 (Termination polyketide synthase)
A, B
291Mycobacterium tuberculosisMutation(s): 0 
Gene Names: pksERS007688_02231
EC: 2.7.7 (PDB Primary Data), 2.3.1 (UniProt)
UniProt
Find proteins for I6X8D2 (Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv))
Explore I6X8D2 
Go to UniProtKB:  I6X8D2
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupI6X8D2
Sequence Annotations
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  • Reference Sequence
Small Molecules
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.94 Å
  • R-Value Free:  0.224 (Depositor), 0.230 (DCC) 
  • R-Value Work:  0.185 (Depositor), 0.190 (DCC) 
  • R-Value Observed: 0.187 (Depositor) 
Space Group: I 1 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 86.9α = 90
b = 38.43β = 101.06
c = 161.078γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
PDB_EXTRACTdata extraction
HKL-2000data reduction
HKL-2000data scaling
REFMACphasing

Structure Validation

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Ligand Structure Quality Assessment 


Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Natural Science Foundation of China (NSFC)China21778019

Revision History  (Full details and data files)

  • Version 1.0: 2022-09-28
    Type: Initial release
  • Version 1.1: 2022-10-19
    Changes: Database references
  • Version 1.2: 2022-10-26
    Changes: Database references
  • Version 1.3: 2023-11-29
    Changes: Data collection, Refinement description