8JZM | pdb_00008jzm

The inhibitor of Toll-like receptor signaling o-vanillin binds covalently to MAL/TIRAP Lys-210

• PDB DOI: https://doi.org/10.2210/pdb8JZM/pdb

• Classification: IMMUNE SYSTEM
• Organism(s): Homo sapiens
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2023-07-05 Released: 2024-05-01 
• Deposition Author(s): Rahaman, M.H., Jia, X., Maxwell, M.J., Mobli, M., Kobe, B.
• Funding Organization(s): Australian Research Council (ARC)

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Experimental Data Snapshot

• Method: SOLUTION NMR
• Conformers Calculated: 200 
• Conformers Submitted: 20 
• Selection Criteria: target function 

Literature

o-Vanillin binds covalently to MAL/TIRAP Lys-210 but independently inhibits TLR2.

Rahaman, M.H., Thygesen, S.J., Maxwell, M.J., Kim, H., Mudai, P., Nanson, J.D., Jia, X., Vajjhala, P.R., Hedger, A., Vetter, I., Haselhorst, T., Robertson, A.A.B., Dymock, B., Ve, T., Mobli, M., Stacey, K.J., Kobe, B.

(2024) J Enzyme Inhib Med Chem 39: 2313055-2313055

• PubMed: 38416868 
• DOI: https://doi.org/10.1080/14756366.2024.2313055
• Primary Citation Related Structures: 
  8JZM


• PubMed Abstract: 
  

  Toll-like receptor (TLR) innate immunity signalling protects against pathogens, but excessive or prolonged signalling contributes to a range of inflammatory conditions. Structural information on the TLR cytoplasmic TIR (Toll/interleukin-1 receptor) domains and the downstream adaptor proteins can help us develop inhibitors targeting this pathway. The small molecule o-vanillin has previously been reported as an inhibitor of TLR2 signalling. To study its mechanism of action, we tested its binding to the TIR domain of the TLR adaptor MAL/TIRAP (MAL ^TIR ). We show that o-vanillin binds to MAL ^TIR and inhibits its higher-order assembly in vitro . Using NMR approaches, we show that o-vanillin forms a covalent bond with lysine 210 of MAL. We confirm in mouse and human cells that o-vanillin inhibits TLR2 but not TLR4 signalling, independently of MAL, suggesting it may covalently modify TLR2 signalling complexes directly. Reactive aldehyde-containing small molecules such as o-vanillin may target multiple proteins in the cell.

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Organizational Affiliation: 
• School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Australia.
Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, Australia.
Institute for Molecular Bioscience, University of Queensland, Brisbane, Australia.
Centre for Advanced Imaging, University of Queensland, Brisbane, Australia.
School of Pharmacy, University of Queensland, Brisbane, Australia.
Institute for Glycomics, Griffith University, Southport, Australia.
Queensland Emory Drug Discovery Initiative, University of Queensland, Brisbane, Australia.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Biological Assembly Evidence: NMR Distance Restraints

Macromolecule Content 

• Total Structure Weight: 16.03 kDa 
• Atom Count: 1,120 
• Modeled Residue Count: 146 
• Deposited Residue Count: 146 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Toll/interleukin-1 receptor domain-containing adapter protein	A	146	Homo sapiens	Mutation(s): 0  Gene Names: TIRAP, MAL
UniProt & NIH Common Fund Data Resources
Find proteins for P58753 (Homo sapiens) Explore P58753  Go to UniProtKB:  P58753
PHAROS:  P58753 GTEx:  ENSG00000150455

Experimental Data & Validation

Experimental Data

• Method: SOLUTION NMR
• Conformers Calculated: 200 
• Conformers Submitted: 20 
• Selection Criteria: target function 

Structure Validation

Entry History 

& Funding Information

Deposition Data

• Released Date: 2024-05-01 
Deposition Author(s): Rahaman, M.H., Jia, X., Maxwell, M.J., Mobli, M., Kobe, B.

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Funding Organization	Location	Grant Number
Australian Research Council (ARC)	Australia	FL180100109

Revision History  

• Version 1.0: 2024-05-01
  Type: Initial release