6C0M

The synthesis, biological evaluation and structural insights of unsaturated 3-N-substituted sialic acids as probes of human parainfluenza virus-3 haemagglutinin-neuraminidase


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.83 Å
  • R-Value Free: 0.228 
  • R-Value Work: 0.181 
  • R-Value Observed: 0.184 

Starting Model: experimental
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This is version 3.1 of the entry. See complete history


Literature

Structural Insights into Human Parainfluenza Virus 3 Hemagglutinin-Neuraminidase Using Unsaturated 3- N-Substituted Sialic Acids as Probes.

Pascolutti, M.Dirr, L.Guillon, P.Van Den Bergh, A.Ve, T.Thomson, R.J.von Itzstein, M.

(2018) ACS Chem Biol 13: 1544-1550

  • DOI: https://doi.org/10.1021/acschembio.8b00150
  • Primary Citation of Related Structures:  
    6C0M

  • PubMed Abstract: 

    A novel approach to human parainfluenza virus 3 (hPIV-3) inhibitor design has been evaluated by targeting an unexplored pocket within the active site region of the hemagglutinin-neuraminidase (HN) of the virus that is normally occluded upon ligand engagement. To explore this opportunity, we developed a highly efficient route to introduce nitrogen-based functionalities at the naturally unsubstituted C-3 position on the neuraminidase inhibitor template N-acyl-2,3-dehydro-2-deoxy-neuraminic acid ( N-acyl-Neu2en), via a regioselective 2,3-bromoazidation. Introduction of triazole substituents at C-3 on this template provided compounds with low micromolar inhibition of hPIV-3 HN neuraminidase activity, with the most potent having 48-fold improved potency over the corresponding C-3 unsubstituted analogue. However, the C-3-triazole N-acyl-Neu2en derivatives were significantly less active against the hemagglutinin function of the virus, with high micromolar IC 50 values determined, and showed insignificant in vitro antiviral activity. Given the different pH optima of the HN protein's neuraminidase (acidic pH) and hemagglutinin (neutral pH) functions, the influence of pH on inhibitor binding was examined using X-ray crystallography and STD NMR spectroscopy, providing novel insights into the multifunctionality of hPIV-3 HN. While the 3-phenyltriazole- N-isobutyryl-Neu2en derivative could bind HN at pH 4.6, suitable for neuraminidase inhibition, at neutral pH binding of the inhibitor was substantially reduced. Importantly, this study clearly demonstrates for the first time that potent inhibition of HN neuraminidase activity is not necessarily directly correlated with a strong antiviral activity, and suggests that strong inhibition of the hemagglutinin function of hPIV HN is crucial for potent antiviral activity. This highlights the importance of designing hPIV inhibitors that primarily target the receptor-binding function of hPIV HN.


  • Organizational Affiliation

    Institute for Glycomics , Griffith University, Gold Coast Campus , Queensland 4222 , Australia.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Hemagglutinin-neuraminidase
A, B
431Human respirovirus 3Mutation(s): 0 
EC: 3.2.1.18
UniProt
Find proteins for G8G134 (Human respirovirus 3)
Explore G8G134 
Go to UniProtKB:  G8G134
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupG8G134
Glycosylation
Glycosylation Sites: 2
Sequence Annotations
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  • Reference Sequence
Oligosaccharides

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Entity ID: 2
MoleculeChains Length2D Diagram Glycosylation3D Interactions
alpha-D-mannopyranose-(1-3)-beta-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose
C
4N-Glycosylation
Glycosylation Resources
GlyTouCan:  G81315DD
GlyCosmos:  G81315DD
GlyGen:  G81315DD
Entity ID: 3
MoleculeChains Length2D Diagram Glycosylation3D Interactions
beta-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose
D
3N-Glycosylation
Glycosylation Resources
GlyTouCan:  G15407YE
GlyCosmos:  G15407YE
GlyGen:  G15407YE
Small Molecules
Ligands 6 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
8LM
Query on 8LM

Download Ideal Coordinates CCD File 
J [auth A],
K [auth A],
R [auth B]
2,6-anhydro-3,5-dideoxy-5-[(2-methylpropanoyl)amino]-3-(4-phenyl-1H-1,2,3-triazol-1-yl)-D-glycero-D-galacto-non-2-enoni c acid
C21 H26 N4 O8
HLCFXRXMEMQOHX-RTKZEXODSA-N
NAG
Query on NAG

Download Ideal Coordinates CCD File 
F [auth A],
M [auth B]
2-acetamido-2-deoxy-beta-D-glucopyranose
C8 H15 N O6
OVRNDRQMDRJTHS-FMDGEEDCSA-N
SO4
Query on SO4

Download Ideal Coordinates CCD File 
I [auth A],
N [auth B],
Q [auth B]
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
GOL
Query on GOL

Download Ideal Coordinates CCD File 
P [auth B]GLYCEROL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
EDO
Query on EDO

Download Ideal Coordinates CCD File 
G [auth A],
H [auth A],
O [auth B]
1,2-ETHANEDIOL
C2 H6 O2
LYCAIKOWRPUZTN-UHFFFAOYSA-N
CA
Query on CA

Download Ideal Coordinates CCD File 
E [auth A],
L [auth B]
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.83 Å
  • R-Value Free: 0.228 
  • R-Value Work: 0.181 
  • R-Value Observed: 0.184 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 83.898α = 90
b = 95.989β = 90
c = 105.61γ = 90
Software Package:
Software NamePurpose
PHENIXrefinement
Aimlessdata scaling
PDB_EXTRACTdata extraction
XDSdata reduction
PHASERphasing

Structure Validation

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Ligand Structure Quality Assessment 


Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Australian Research Council (ARC)AustraliaDP1094549
National Health and Medical Research Council (NHMRC, Australia)AustraliaID1047824
National Health and Medical Research Council (NHMRC, Australia)AustraliaID1071659

Revision History  (Full details and data files)

  • Version 1.0: 2018-06-27
    Type: Initial release
  • Version 1.1: 2019-04-17
    Changes: Author supporting evidence, Data collection
  • Version 1.2: 2020-01-01
    Changes: Author supporting evidence
  • Version 2.0: 2020-04-22
    Changes: Advisory, Atomic model, Data collection
  • Version 3.0: 2020-07-29
    Type: Remediation
    Reason: Carbohydrate remediation
    Changes: Atomic model, Data collection, Derived calculations, Structure summary
  • Version 3.1: 2023-10-04
    Changes: Data collection, Database references, Derived calculations, Refinement description, Structure summary