Search bioRxiv⌕ Search
Home/Archive/bioRxiv

bioRxiv · 10.1101/2024.05.19.594723

Viral methyltransferase inhibitors: berbamine, venetoclax, and ponatinib as efficacious antivirals against Chikungunya virus

Bhutkar, M.·Saha, A.·Tomar, S.
View original source ↗Export metadata ↓

Abstract

Chikungunya virus (CHIKV), transmitted by mosquitoes, poses a significant global health threat. Presently, no effective treatment options are available to reduce the disease burden. The lack of approved therapeutics against CHIKV and the complex spectrum of chronic musculoskeletal and neurological manifestations raise significant concerns, and repurposing drugs could offer swift avenues in the development of effective treatment strategies. RNA capping is a crucial step meditated by non-structural protein 1 (nsP1) in CHIKV replication. In this study, FDA-approved antivirals targeting CHIKV nsP1 methyltransferase (MTase) have been identified by structure-based virtual screening. Berbamine Hydrochloride (BH), ABT199/Venetoclax (ABT), and Ponatinib (PT) were the top hits, which exhibited robust binding energies. Tryptophan fluorescence spectroscopy-based assay confirmed binding of BH-, ABT-, and PT to purified nsP1 with KD values [~]5.45 M, [~]161.3 M, and [~]3.83M, respectively. A dose-dependent decrease in CHIKV nsP1 MTase activity was observed in a capillary electrophoresis-based assay. Treatment with BH, ABT, and PT lead to a dose-dependent reduction in the virus titer with IC50 <100, [~]3.46, and <3.9 nM, respectively, and reduced viral mRNA levels. The nsP1 MTases are highly conserved among alphaviruses; therefore, BH, ABT, and PT, as expected, inhibited replication machinery in Sindbis virus (SINV) replicon assay with IC50 [~]1.94, [~]0.23, and >1.25 M, respectively. These results underscore the efficacy and promise of repurposing drugs as rapid and effective antiviral therapeutics against CHIKV. HighlightsO_LIBerbamine Hydrochloride (BH), ABT199/Venetoclax (ABT), and Ponatinib (PT) identified as inhibitors of Chikungunya virus (CHIKV) nsP1 C_LIO_LIMolecules BH, ABT and PT make moelcular interactions with nsP1: KD values [~]5.45, [~]161.3, and [~]3.83 in M, respectively and effectively inhibit methyltransferase activity. C_LIO_LIBH, ABT, and PT exhibited potent antiviral activity against CHIKV in cell-based assays, with IC50 <100, [~]3.46, and <3.9 nM. C_LIO_LIBH, ABT, and PT also inhibit Sindbis virus, the prototype alphavirus with IC50 [~]1.94, [~]0.23, and >1.25 M respectively demonstrating broad spectrum antiviral efficacy. C_LI Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=117 SRC="FIGDIR/small/594723v1_ufig1.gif" ALT="Figure 1"> View larger version (31K): org.highwire.dtl.DTLVardef@1af985dorg.highwire.dtl.DTLVardef@13c14fforg.highwire.dtl.DTLVardef@1868785org.highwire.dtl.DTLVardef@12b690a_HPS_FORMAT_FIGEXP M_FIG C_FIG

Source connections

Explore related subjects

microbiologyPreprint

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Bhutkar, M., Saha, A., Tomar, S.. 2024-05-19. Viral methyltransferase inhibitors: berbamine, venetoclax, and ponatinib as efficacious antivirals against Chikungunya virus. https://doi.org/10.1101/2024.05.19.594723

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

bioRxiv2026

A population-scale landscape of the subgingival microbiome reveals divergent routes to periodontal dysbiosis

Periodontitis is an archetypical mucosal inflammatory disease in which microbiome dysbiosis at the tooth-epithelial interface interacts with host genetic and behavioral risk factors to drive immune-mediated tissue destruction. Although subgingival microbiome compositional shifts are thought to parallel disease severity, microbiome variation at the population-level and its relationship to periodontal clinical phenotypes and disease-modifying factors remain poorly defined. Here, we use unsupervised manifold learning to map the compositional landscape of the subgingival microbiome in 1,355 adults spanning periodontal health to severe periodontitis. We identified eight latent microbiome states organized along a branching continuum from eubiosis to dysbiosis. An intermediate microbial configuration marked ecological destabilization and bifurcation into two distinct periodontitis-associated dysbiotic trajectories, distinguished by links to gingival inflammation and smoking. Although the microbiome trajectories broadly tracked periodontal destruction, a minority of individuals showed discordant microbiome-clinical phenotypes, with some individuals with periodontitis retaining otherwise eubiotic microbiomes enriched for low-abundance pathobionts, while some cases of health or mild disease had highly dysbiotic communities, suggesting distinct host susceptibility. Together, these findings define a population-scale ecological landscape of the subgingival microbiome, reveal divergent trajectories to periodontal dysbiosis, and highlight heterogeneity in the relationship between microbial community structure and clinical disease expression.

microbiology↗
bioRxiv2026

The iron-binding siderophore enterobactin is required for the response of multi-drug resistant Klebsiella pneumoniae to zinc limitation

To persist during infection Klebsiella pneumoniae must overcome nutrient iron and zinc limitation imposed by the host immune system through a process called nutritional immunity. Secreted small molecule siderophores are a major virulence determinant of Klebsiella pneumoniae pathogenesis and are presumed to overcome nutritional immunity by binding iron for bacterial acquisition. In this work, we set out to identify how a multi-drug resistant K. pneumoniae grows in zinc limited environments. Using unbiased transcriptomics, proteomics, and an arrayed transposon screen, we identified that synthesis and uptake of the siderophore enterobactin is required to allow for growth in low zinc conditions. Iron-specific chelators did not replicate this phenotype and addition of supplemental iron through heme in growth media could not complement severe growth defects of enterobactin mutant K. pneumoniae experiencing zinc limitation. Finally, zinc starvation induced enterobactin production independent of the canonical zinc uptake regulator (Zur) transcription factor suggesting an unidentified regulatory mechanism by which Gram-negative pathogens may respond to zinc stress. Together, these studies expand the role of enterobactin beyond iron regulation and highlight a previously unreported link between iron and zinc homeostasis in Klebsiella pneumoniae.

microbiology↗
bioRxiv2026

A microbiota-derived protease links phage susceptibility to host epithelial responses

Bacteriophages are major ecological drivers of gut microbial ecology, yet whether bacterial mechanisms that determine phage susceptibility have consequences for the mammalian host remains poorly understood. Here, we identify dipeptidyl peptidase 11 (Dpp11a), the predominant active serine protease of the prevalent gut commensal Phocaeicola vulgatus, as an unexpected bacterial defence factor. Dpp11a protects against environmental proteases and confers resistance to bacteriophage infection. Metatranscriptomic analyses further reveal increased expression of both dpp11a and P. vulgatus-associated phage transcripts in ulcerative colitis stool samples, indicating that both components of this interaction are transcriptionally active in disease-associated human microbiomes. Using the microfluidic gut-on-a-chip co-culture model HuMiX, we show that the absence of Dpp11 is accompanied by altered epithelial tight-junction remodelling during phage-bacterial infection. Together, our findings reveal that the consequences of bacterial phage defence can extend beyond phage-bacterium interactions to the mammalian epithelium.

microbiology↗