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Cyanobacteria as a critical reservoir of the environmental antimicrobial resistome.

Antimicrobial resistance (AMR) is predicted to cause a worldwide annual toll of 10 million deaths by 2050. This looming public health threat … racyclines, macrolides, and aminoglycosides were associated with mobile genetic elements or plasmid replicons or both. These results suggest that cyanobacteria are an extensive reservoir, and potential vector, for AMR genes in diverse terrestrial and aquatic habitats.

Thymidine rescues ATR kinase inhibitor-induced deoxyuridine contamination in genomic DNA, cell death, and interferon-α/β expression.

ATR kinase is a central regulator of the DNA damage response (DDR) and cell cycle checkpoints. ATR kinase inhibitors (ATRi's) combine with radiation to generate CD8+ T cell-dependent responses in mouse models of cancer. We show that ATRi's induce cyclin-dependent kinase 1 (CDK1)-dependent origin firing across active replicons in CD8+ T cells activated ex vivo while simultaneously decreasing the activity of rate-limiting enzymes for nucleotide biosynthesis. These pleiotropic effects of ATRi induce deoxyuridine (dU) contamination in genomic DNA, R loops, RNA-DNA polymerase collisions, and interf…

Genomics and transcriptomics insights into luteolin effects on the beta-rhizobial strain Cupriavidus necator UYPR2.512.

Cupriavidus necator UYPR2.512 is a rhizobial strain that belongs to the Beta-subclass of proteobacteria, able to establish successful symbiosis with Mimosoid legumes. The initial steps of rhizobium-legumes symbioses involve the reciprocal recognition by chemical signals, being luteolin one of the molecules involved. However, there is a lack of information on the effect of luteolin in beta-rhizobia. In this work, we used long-read sequencing to complete the genome of UYPR2.512 providing evidence for the existence of four closed circular replicons. We used an RNA-Seq approach to analyse the resp…

Vectors expressing chimeric Japanese encephalitis dengue 2 viruses.

Vectors based on self-replicating RNAs (replicons) of flaviviruses are becoming powerful tool for expression of heterologous genes in mammalian cells and development of novel antiviral and anticancer vaccines. We constructed two vectors expressing chimeric viruses consisting of attenuated SA14-14-2 strain of Japanese encephalitis virus (JEV) in which the PrM/M-E genes were replaced fully or partially with those of dengue 2 virus (DENV-2). These vectors, named pJED2 and pJED2-1770 were transfected to BHK-21 cells and produced chimeric viruses JED2V and JED2-1770V, respectively. The chimeric vir…

Mobilizable narrow host range plasmids as natural suicide vectors enabling horizontal gene transfer among distantly related bacterial species.

Klebsiella pneumoniae 287-w carries three small narrow host range (NHR) plasmids (pIGMS31, pIGMS32, and pIGRK), which could be maintained in … r to phage-related integrases. The MOBs of pIGMS31 and pIGMS32 enabled the transfer of heterologous replicons from E. coli into both gammaproteobacterial and alphaproteobacterial hosts, which suggests that these NHR plasmids contain broad host range MOB systems. Such plasmids therefore represent efficient carrier molecules, which may act as natural suicide …

Alphaviruses: Semliki forest virus and Sindbis virus vectors for gene transfer into neurons.

Alphaviral vectors based on Semliki Forest virus and Sindbis virus infect many host cell types, causing rapid and high-level transgene expre … er alphavirus vectors based on Venezuelan equine encephalitis and Eastern equine encephalitis virus replicons have been engineered, too. Alphavirus vectors have been successfully used not only in neuroscience, but also for other applications including drug discovery, structural biology, vaccine development, and cancer therapy.

Analysis of pMA67, a predicted rolling-circle replicating, mobilizable, tetracycline-resistance plasmid from the honey bee pathogen, Paenibacillus larvae.

This work characterizes a recently discovered natural tetracycline-resistance plasmid called pMA67 from Paenibacillus larvae--a Gram-positive bacterial pathogen of honey bees. We provide evidence that pMA67 replicates by the rolling-circle mechanism, and sequence comparisons place it in the pMV158 family of rolling-circle replicons. The plasmid contains predicted rep, cop, and rnaII genes for control of replication initiating at a predicted double-strand origin. The plasmid has an ssoT single-strand origin, which is efficient enough to allow only very small amounts of the single-stranded DNA i…

Protection from Ebola virus mediated by cytotoxic T lymphocytes specific for the viral nucleoprotein.

Cytotoxic T lymphocytes (CTLs) are proposed to be critical for protection from intracellular pathogens such as Ebola virus. However, there have been no demonstrations that protection against Ebola virus is mediated by Ebola virus-specific CTLs. Here, we report that C57BL/6 mice vaccinated with Venezuelan equine encephalitis virus replicons encoding the Ebola virus nucleoprotein (NP) survived lethal challenge with Ebola virus. Vaccination induced both antibodies to the NP and a major histocompatibility complex class I-restricted CTL response to an 11-amino-acid sequence in the amino-terminal po…

[Constructing a test system for the identification of plague microbe based on genetic probes].

DNA probes for detection of the plague agent Yersinia pestis were made on a basis of its three typical extrachromosomal replicons. The recombinant plasmid pBS2 including pBR327 vector and SalGI-BspRI fragment of the plasmid pFra was constructed. The above fragment is connected with synthesis of Y. pestis capsular antigen and it is a 400 bp species-specific DNA probe called F1 which is suitable for identification of Y. pestis species that bears the 60 mdal plasmid. The DNA probes called P1 was made on a basis of the plasmid pPst; it is the 460 BglII-BamHI fragment of the fibrinolysin-coagulase …

Identification of host genes involved in hepatitis C virus replication by small interfering RNA technology.

UNLABELLED: Hepatitis C virus (HCV) replication is highly dependent on host cell factors. Identification of these host factors not only facilitates understanding of the biology of HCV infection but also enables the discovery of novel targets for anti-HCV therapy. To identify host genes important for HCV RNA replication, we screened a library of small interfering RNA (siRNA) that targets approximately 4,000 human genes in Huh7-derived EN5-3 cells harboring an HCV subgenomic replicon with the nonstructural region NS3-NS5B from the 1b-N strain. Nine cellular genes that potentially regulate HCV re…

Transposon insertion sequencing identifies novel genes involved in product synthesis in gas-fermenting Clostridium ljungdahlii.

The efficient utilization of industrial one-carbon (C1) gases, such as carbon dioxide (CO2) and carbon monoxide (CO), has attracted widespre … e the library's relatively low plasmid curing efficiency by employing an IPTG-regulated conditional replicon. Subsequent high-throughput transposon insertion sequencing (Tn-seq) of this library allowed for the rapid exploration of a broad set of genes potentially involved in growth on syngas. Experimental validation of these candidate genes revealed severa …

Anti-Zika Virus Activity of Azvudine via Inhibition of RNA Replication by Its Active Triphosphate Form.

The outbreak of the Zika virus (ZIKV) poses a significant threat to global public health. Currently, there are no approved antiviral drugs specifically targeting ZIKV. This highlights the urgent need for the development of effective therapeutic agents. Azvudine (FNC), an antiviral drug approved in China for treating HIV/AIDS and later granted conditional approval for COVID-19, is a promising candidate for drug repurposing. In this study, we found FNC inhibited ZIKV replication in a cell-based replicon system we established. This inhibition was confirmed by significant reductions in ZIKV RNA an…

Preclinical evaluation of GW406108X, a broad-spectrum therapeutic blocking ULK1/2-mediated autophagy to inhibit enterovirus replication.

Enterovirus D68 (EV-D68) is an emerging respiratory pathogen, with severe cases developing into acute flaccid myelitis, a paralytic conditio … post-entry inhibitor of EV-D68 infection (EC50: 1.804 μmol/L). Mechanistic studies using luciferase replicon assays, siRNA knockdowns, and drug-resistant mutant generation suggest that GW406108X targets the autophagy pathway through ULK1/2 inhibition. Transmission electron microscopy and fluorescence bioimaging demonstrate a significant reduction in autoph …

Longitudinal genomic insights into resistance and virulence dynamics of Klebsiella pneumoniae clinical isolates from Pakistan.

Multidrug resistant K. pneumoniae is a public health treat in Pakistan, yet longitudinal genomic data on the evolution of resistance and vir … ani isolates (2010 vs. 2019). Pan-genome analysis, resistance and virulence gene profiling, plasmid replicon identification, genotype-phenotype concordance, and phylogenetic reconstruction was performed. Alarmingly, 90% of isolates were MDR while 13% were extensively drug-resistant. Carbapenem resistance exceeded 60%, mainly due to blaNDM−1 and blaNDM−5 in …

Ядерная деятельность и взаимодействие белка NS5 ник-Борна энцефалита.

Орфолавирусы являются вирусами РНК, вызывающими значительные заболевания у людей, одомашненных животных и животных. Их протеин NS5 играет центральную роль в репликации вирусов, действуя как в качестве полимеразы РНК, зависимой от РНК, так и в качестве метилпереносазы, одновременно модифицируя клеточные процессы, включая интерферонную реакцию. Несмотря на то, что вирусное воспроизведение носит цитоплазмический характер, белок NS5 из нескольких переносимых комарами ортофлавирных циклов между цитоплазмой и ядром инфицированных человеческих клеток. Однако ядерная локализация и функция NS5 переноси

Совпадение в аннотации оригинала
Orthoflaviviruses are RNA viruses responsible for significant diseases in humans, domesticated animals and wildlife. Their NS5 protein is ce … identified critical residues required for its nuclear targeting. Mutating these residues in a TBEV replicon abolished viral replication. Immunoprecipitation-mass spectrometry analyses performed in two human cell lines infected with TBEV recovered 352 NS5 partners. Among them, 187 were nuclear or partially nuclear. By integrating our interactome data with …

Shifting genomes, rising threats: Adaptive evolution and antimicrobial resistance of E. coli ST10 across African ecologies.

Escherichia coli sequence type 10 (ST10) is an emerging zoonotic lineage with global distribution and a high antimicrobial resistance (AMR) … multidrug-resistant, with 29% carrying the extended-spectrum β-lactamase gene bla_CTX-M-15. Plasmid replicon analysis highlighted the widespread presence of IncFIB and ColRNAI plasmids, strongly linked to AMR gene carriage. Human-derived isolates predominated both phylogenetic clusters and resistance profiles. SNP-based comparisons revealed evidence of bot …

Emerging infection and nosocomial transmission of carbapenem-resistant Klebsiella pneumoniae harboring blaNDM-21 in a neonatal intensive care unit.

Carbapenem-resistant Klebsiella pneumoniae (CRKP) represents a significant threat in neonatal intensive care units (NICU) because of its high antimicrobial resistance and association with increased mortality rates. In our study, we identified three blaNDM-21-harboring CRKP isolates from three critically ill pediatric inpatients; these isolates underwent comprehensive analysis. Our investigations included assessments of their clinical spatiotemporal distribution, antimicrobial susceptibilities, whole-genome sequencing (WGS), biological properties, and genomic and plasmid replicon typing. The th…

Clonal diversity and plasmid-mediated emergence of NDM-1-producing Raoultella ornithinolytica in clinical isolates.

OBJECTIVE: Raoultella ornithinolytica is recognized as an emerging opportunistic pathogen, with sporadic reports of multidrug resistance. Ho … s were characterized using antimicrobial susceptibility testing, resistance gene detection, plasmid replicon typing, pulsed-field gel electrophoresis, conjugation assays, and whole-genome sequencing. RESULTS: Among the 13 isolates, 10 harboured blaNDM-1, seven of which carried the gene on IncX3 plasmids. Despite clonal diversity, six of the 13 isolates sh …

Development and Immunogenic Evaluation of a Recombinant Vesicular Stomatitis Virus Expressing Nipah Virus F and G Glycoproteins.

Nipah virus (NiV) is a highly pathogenic bat-borne zoonotic pathogen that poses a significant threat to human and animal health, with fatality rates exceeding 70% in some outbreaks. Despite its significant public health impact, there are currently no licensed vaccines or specific therapeutics available. Various virological tools-such as reverse genetics systems, replicon particles, VSV-based pseudoviruses, and recombinant Cedar virus chimeras-have been widely used to study the molecular mechanisms of NiV and to support vaccine development. Building upon these platforms, we developed a replicat…

Compounds Isolated from Paepalanthus spp. (Eriocaulaceae) and Their Evaluation in Antimicrobial, Cytotoxic, and Antiviral Assays.

Paepalanthus acanthophyllus and P. bromelioides belong to the Eriocaulaceae family. According to the literature, secondary metabolites isola … 0 = 1.95 μM); however, it did not show inhibition when evaluated in phenotypic assays with the ZIKV replicon.