Fragment-based screening identifies novel targets for inhibitors of conjugative transfer of antimicrobial resistance by plasmid pKM101

Casu, Bastien; Arya, T.; Bessette, Benoit; Baron, Christian

doi:10.1038/s41598-017-14953-1

Cited by 19 publications

(17 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…[59,60] In the meantime,t he limitations of current compound libraries have been understood and contemporary approaches are being pursued to broaden the chemical space used for antibacterial screenings.N ew libraries are generated using combinatorial and diversity-oriented synthesis [61][62][63][64] or smallmolecule fragments. [65][66][67][68] These libraries are mostly used for the targeted screening of purified proteins.…”

Section: Synthetic Libraries and Target-based Screensmentioning

confidence: 99%

Thinking Outside the Box—Novel Antibacterials To Tackle the Resistance Crisis

et al. 2018

View full text Add to dashboard Cite

The public view on antibiotics as reliable medicines changed when reports about "resistant superbugs" appeared in the news. While reasons for this resistance development are easily spotted, solutions for re-establishing effective antibiotics are still in their infancy. This Review encompasses several aspects of the antibiotic development pipeline from very early strategies to mature drugs. An interdisciplinary overview is given of methods suitable for mining novel antibiotics and strategies discussed to unravel their modes of action. Select examples of antibiotics recently identified by using these platforms not only illustrate the efficiency of these measures, but also highlight promising clinical candidates with therapeutic potential. Furthermore, the concept of molecules that disarm pathogens by addressing gatekeepers of virulence will be covered. The Review concludes with an evaluation of antibacterials currently in clinical development. Overall, this Review aims to connect select innovative antimicrobial approaches to stimulate interdisciplinary partnerships between chemists from academia and industry.

show abstract

Section: Synthetic Libraries and Target-based Screensmentioning

confidence: 99%

Thinking Outside the Box—Novel Antibacterials To Tackle the Resistance Crisis

et al. 2018

View full text Add to dashboard Cite

show abstract

“…The translocation of gingipains to OMVs occurs via a recently discovered type IX secretion system (T9SS) . Targeting this secretion pathway may hinder the destructive effect we observed on the sBL.…”

Section: Discussionmentioning

confidence: 98%

Selective bacterial degradation of the extracellular matrix attaching the gingiva to the tooth

Fouillen

Grenier

Barbeau

et al. 2019

European J Oral Sciences

Self Cite

View full text Add to dashboard Cite

The junctional epithelium (JE) is a specialized portion of the gingiva that seals off the tooth‐supporting tissues from the oral environment. This relationship is achieved via a unique adhesive extracellular matrix that is, in fact, a specialized basal lamina (sBL). Three unique proteins – amelotin (AMTN), odontogenic ameloblast‐associated (ODAM), and secretory calcium‐binding phosphoprotein proline‐glutamine rich 1 (SCPPPQ1) – together with laminin‐332 structure the supramolecular organization of this sBL and determine its adhesive capacity. Despite the constant challenge of the JE by the oral microbiome, little is known of the susceptibility of the sBL to bacterial degradation. Assays with trypsin‐like proteases, as well as incubation with Porphyromonas gingivalis, Prevotella intermedia, and Treponema denticola, revealed that all constituents, except SCPPPQ1, were rapidly degraded. Porphyromonas gingivalis was also shown to alter the supramolecular network of reconstituted and native sBLs. These results provide evidence that proteolytic enzymes and selected gram‐negative periodontopathogenic bacteria can attack this adhesive extracellular matrix, intimating that its degradation could contribute to progression of periodontal diseases.

show abstract

“…1). The optimized assay conditions were used to screen a library of 505 fragments [24,32] (supplementary Fig. 1) and 16 molecules (supplementary Fig.…”

Section: Differential Scanning Fluorimetry To Identify Cagα-binding Fmentioning

confidence: 99%

“…Since T4SS are important for bacterial virulence they are very interesting targets for the development of drugs that disarm but do not kill bacterial pathogens [20,21]. In our previous work, we have identified inhibitors of the dimerization of VirB8-like proteins from B. suis and plasmid pKM101 using the bacterial two-hybrid system and fragment-based screening approaches and we identified molecules that reduce T4SS function [22][23][24][25]. Other groups have identified peptidomimetic inhibitors of the H. pylori T4SS, but the targets of these molecules are not known [26].…”

Section: Introductionmentioning

confidence: 99%

Fragment-based screening identifies inhibitors of the ATPase activity and of hexamer formation of Cagα from the Helicobacter pylori type IV secretion system

Arya

Oudouhou

Casu

et al. 2018

Preprint

Self Cite

View full text Add to dashboard Cite

Type IV secretion systems are membrane-bound multiprotein complexes that mediate the translocation of macromolecules across the bacterial cell envelope. In Helicobacter pylori a type IV secretion system is encoded by the cag pathogenicity island that encodes 27 Cag proteins and most of these are essential for bacterial virulence. We here present our work on the identification and characterization of inhibitors of Cagα, a hexameric ATPase and member of the family of VirB11-like proteins that is essential for translocation of the CagA cytotoxin into mammalian cells. We conducted fragment-based screening using a differential scanning fluorimetry assay and identified 16 molecules that stabilize the protein during thermal denaturation suggesting that they bind Cagα. Several of these molecules affect binding of ADP and four of them inhibit the ATPase enzyme activity of Cagα.Analysis of enzyme kinetics suggests that their mode of action is non-competitive, suggesting that they do not bind to the ATPase active site. Cross-linking analysis suggests that the active molecules change the conformation of the protein and gel filtration and transmission electron microscopy show that molecule 1G2 dissociates the Cagα hexamer. Analysis by X-ray crystallography reveals that molecule 1G2 binds at the interface between Cagα subunits. Addition of the molecule 1G2 inhibits the induction of interleukin-8 production in gastric cancer cells after co-incubation with H. pylori suggesting that it inhibits Cagα in vivo. Our results reveal a novel mechanism for the inhibition of the ATPase activity of VirB11-like proteins and the identified molecules have potential for the development into antivirulence drugs. Author summaryWe here report the results of a small-molecule screening approach to identify inhibitors of an essential virulence factor from the gastrointestinal pathogen Helicobacter pylori. We identifed novel chemical entities that bind to the Cagα protein and inhibit its function. We discovered a novel inhibitor binding site that disrupts the hexameric quaternary structure and inhibits ATPase enzyme activity of Cagα. Based on the structural information on the binding site, these molecules could be developed into high-affinity inhibitors that may have potential as anti-virulence drugs. This approach represents a generally applicable strategy for the inhibition of bacterial virulence factors for which structural information is available that could be applied to target similar proteins from many bacterial pathogens.

show abstract

Fragment-based screening identifies novel targets for inhibitors of conjugative transfer of antimicrobial resistance by plasmid pKM101

Cited by 19 publications

References 23 publications

Thinking Outside the Box—Novel Antibacterials To Tackle the Resistance Crisis

Thinking Outside the Box—Novel Antibacterials To Tackle the Resistance Crisis

Selective bacterial degradation of the extracellular matrix attaching the gingiva to the tooth

Fragment-based screening identifies inhibitors of the ATPase activity and of hexamer formation of Cagα from the Helicobacter pylori type IV secretion system

Contact Info

Product

Resources

About