Discovery of Compounds Inhibiting the ADP-Ribosyltransferase
Activity of Pertussis Toxin
Yashwanth Ashok
Moona Miettinen
Danilo Kimio Hirabae
de Oliveira
Mahlet Z. Tamirat
Katja Näreoja
Avlokita Tiwari
Michael O. Hottiger
Mark S. Johnson
Lari Lehtiö
Arto T. Pulliainen
10.1021/acsinfecdis.9b00412.s001
https://acs.figshare.com/articles/journal_contribution/Discovery_of_Compounds_Inhibiting_the_ADP-Ribosyltransferase_Activity_of_Pertussis_Toxin/11573418
The targeted pathogen-selective approach
to drug development holds promise to minimize collateral damage to
the beneficial microbiome. The AB<sub>5</sub>-topology pertussis toxin
(PtxS1-S5) is a major virulence factor of <i>Bordetella pertussis</i>, the causative agent of the highly contagious respiratory disease
whooping cough. Once internalized into the host cell, PtxS1 ADP-ribosylates
α-subunits of the heterotrimeric Gαi-superfamily, thereby
disrupting G-protein-coupled receptor signaling. Here, we report the
discovery of the first small molecules inhibiting the ADP-ribosyltransferase
activity of pertussis toxin. We developed protocols to purify milligram-levels
of active recombinant <i>B. pertussis</i> PtxS1 from <i>Escherichia coli</i> and an <i>in vitro</i> high throughput-compatible
assay to quantify NAD<sup>+</sup> consumption during PtxS1-catalyzed
ADP-ribosylation of Gαi. Two inhibitory compounds (NSC228155
and NSC29193) with low micromolar IC<sub>50</sub>-values (3.0 μM
and 6.8 μM) were identified in the <i>in vitro</i> NAD<sup>+</sup> consumption assay that also were potent in an independent <i>in vitro</i> assay monitoring conjugation of ADP-ribose to Gαi.
Docking and molecular dynamics simulations identified plausible binding
poses of NSC228155 and in particular of NSC29193, most likely owing
to the rigidity of the latter ligand, at the NAD<sup>+</sup>-binding
pocket of PtxS1. NSC228155 inhibited the pertussis AB<sub>5</sub> holotoxin-catalyzed
ADP-ribosylation of Gαi in living human cells with a low micromolar
IC<sub>50</sub>-value (2.4 μM). NSC228155 and NSC29193 might
prove to be useful hit compounds in targeted <i>B. pertussis</i>-selective drug development.
2020-01-10 21:29:49
NAD
PtxS 1. NSC 228155
pertussis PtxS 1
drug development
micromolar IC 50
G αi
heterotrimeric G αi
G αi Docking
PtxS 1 ADP-ribosylates α- subunits
topology pertussis toxin
pertussis AB 5 holotoxin-catalyzed ADP-ribosylation
PtxS 1-catalyzed ADP-ribosylation
assay monitoring conjugation
1-S
NSC 228155
6.8 μ M