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Draft Genome Sequence of Proteus mirabilis NO-051/03, Representative of a Multidrug-Resistant Clone Spreading in Europe and Expressing the CMY-16 AmpC-Type β-Lactamase.

Proteus mirabilis NO-051/03, representative of a multidrug-resistant clone expressing the CMY-16 AmpC-type β-lactamase and circulating in Europe since 2003, was sequenced by a MiSeq platform using a paired-end approach. The genome was assembled in 100 scaffolds with a total length of 4,197,318 bp. Analysis of the draft genome sequence revealed the presence of several acquired resistance determinants to β-lactams, aminoglycosides, phenicols, tetracyclines, trimethoprim, and sulfonamides, of one plasmid replicon, and of a type I-E clustered regularly interspaced short palindromic repeat (CRISPR)…

Dissemination of the KPC-2 carbapenemase in non-Klebsiella pneumoniae enterobacterial isolates from Colombia.

Klebsiella pneumoniae carbapenemase (KPC)-type enzymes have largely disseminated worldwide among K. pneumoniae isolates. In this study, 11 non-K. pneumoniae KPC-producing enterobacterial isolates from four hospitals located in different Colombian cities were genetically investigated. All isolates were multidrug-resistant and harboured the bla(KPC-2) gene along with several other acquired β-lactamase genes. The bla(KPC-2) gene was associated with transposon Tn4401b inserted in different loci of plasmids varying in size and replicon type. The presence of KPC-2 in different enterobacterial specie…

Identification of a series of compounds with potent antiviral activity for the treatment of enterovirus infections.

Rhinovirus (genus enterovirus) infections are responsible for many of the severe exacerbations of asthma and chronic obstructive pulmonary d … n established as inhibition of a lipid kinase, PI4KIIIβ. Inhibition of hepatitis C replication in a replicon assay correlated with enterovirus inhibition.

Restoring virulence to mutants lacking subunits of multiprotein machines: functional complementation of a Brucella virB5 mutant.

Complementation for virulence of a non-polar virB5 mutant in Brucella suis 1330 was not possible using a pBBR-based plasmid but was with low copy vector pGL10. Presence of the pBBR-based replicon in wildtype B. suis had a dominant negative effect, leading to complete attenuation in J774 macrophages. This was due to pleiotropic effects on VirB protein expression due to multiple copies of the virB promoter region and over expression of VirB5. Functional complementation of mutants in individual components of multiprotein complexes such as bacterial secretion systems, are often problematic; this s…

Кератиноциты являются клеточными объектами вируса Западного Нила в vivo.

Вирус Западного Нила (ВНВ) копируется в коже; однако цели клеток в коже не определены. В ходе текущих исследований WNV заразил эпидермис и аднексальные железы кожи мыши, а эпидермальные клетки были определены как кератиноциты путем двойной маркировки антигена и кератина 10. Прививка мышей репликоновыми частицами WNV привела к высоким уровням воспроизведения в коже, что говорит о том, что кератиноциты являются первоначальной целью WNV. Кроме того, первичные кератиноциты производят инфекционные вирусы in vitro. В заключение следует отметить, что кератиноциты являются клеточными объектами ВНВ в v

Совпадение в аннотации оригинала
West Nile virus (WNV) replicates in the skin; however, cell targets in the skin have not been identified. In the current studies, WNV infected the epidermis and adnexal glands of mouse skin, and the epidermal cells were identified as keratinocytes by double labeling for WNV antigen and keratin 10. Inoculation of mice with WNV replicon particles resulted in h…

Evidence for arbovirus dissemination conduits from the mosquito (Diptera: Culicidae) midgut.

The mechanism by which arboviruses bypass the basal lamina of mosquito midgut cells and enter the body cavity has been unclear. Experiments using Venezuelan equine encephalitis viral replicon particles, which express the green fluorescent protein gene in cells, indicate the operation of tissue conduits, possibly involving tracheae and visceral muscles, that facilitate virus movement through the basal lamina. Ultrastructural studies of the midgut reveal evidence for possible complete penetration of the basal lamina by tracheal cells and regions of modified basal lamina associated with visceral …

mcr-1 Identified in Fecal Escherichia coli and Avian Pathogenic E. coli (APEC) From Brazil.

Colisitin-associated resistance in bacteria of food producing animals has gained significant attention with the mcr gene being linked with r … rophoresis (PFGE) analysis, avian fecal E. coli (APEC) virulence associated gene screening, plasmid replicon typing and antimicrobial resistance phenotype and resistance gene screening, were also carried out to further characterize these isolates. The mcr-1 gene was detected in 62 (57.9%) isolates (61 healthy and 1 APEC) and the mcr-5 gene was detected in …

Benzohydroxamic acids as potent and selective anti-HCV agents.

A diverse collection of 40 derivatives of benzohydroxamic acid (BHAs) of various structural groups were synthesized and tested against hepatitis C virus (HCV) in full-genome replicon assay. Some of these compounds demonstrated an exceptional activity, suppressing viral replication at sub-micromolar concentrations. The compounds were inactive against key viral enzymes NS3, and NS5B in vitro assays, suggesting host cell inhibition target(s). The testing results were consistent with metal coordination by the BHAs hydroxamic group in complex with a target(s). Remarkably, this class of compounds di…

Selection of an optimal RNA transfection reagent and comparison to electroporation for the delivery of viral RNA.

The initiation of viral RNA replication by the transfection of viral RNA is an integral tool in dissecting the life cycles, susceptibility, … were compared for their ability to deliver yellow fever virus (YFV) and hepatitis C virus (HCV) RNA replicons into Huh7 cells. The performance of the commercial transfection reagents was also compared directly to electroporation. When properly optimized, certain reagents were superior to electroporation, with much less cell death, less RNA required and inc …

Uncoupling the chemical steps of telomere resolution by ResT.

ResT is the telomere resolvase of the spirochete Borrelia burgdorferi, the causative agent of Lyme disease. ResT is an essential cellular function that processes replication intermediates to produce linear replicons terminated by covalently closed hairpin telomeres. ResT generates these hairpin telomeres in a reaction with mechanistic similarities to those catalyzed by type IB topoisomerases and tyrosine recombinases. We report here, that like most of the tyrosine recombinases, ResT requires interprotomer communication, likely in an in-line synapse, to activate reaction chemistry. Unlike the t…

The effect of bleomycin on DNA synthesis in ataxia telangiectasia lymphoid cells.

Bleomycin, a radiomimetic glycopeptide, inhibits de novo DNA synthesis in ataxia telangiectasia lymphoblastoid B cells to a markedly lesser extent than in normal and xeroderma pigmentosum lymphoid cells. This observation is similar to that following ionizing radiation; however, the effect is slower following the chemical treatment. Recovery of the normal cells occurs 15-18 hours after treatment, whereas the ataxia telangiectasia lines do not attain normal levels of DNA synthesis during the entire 24-hour observation period. Similar differences were not observed following treatment with mitomyc

[Contribution of determinants, located in Bacillus anthracis chromosomes, in realizing the pathogenic properties of the pathogen].

Comparative study of virulence of B. anthracis strains harbouring pXO1 and pXO2 plasmids in mice and guinea pigs showed that among six B. anthracis strains, three were 100-1000 times less virulent for guinea pigs. Genetic construction of B. anthracis strains using transduction and conjugation transfer of resident plasmids permitted us to rule out the effects of modified pXO1 and pXO2 replicons and to prove the existence of nonidentified chromosome locuses responsible for the development of an infectious process in anthrax, along with plasmid determinants of virulence.

Identification, cloning and sequencing of the replication region of Lactococcus lactis ssp. lactis biovar. diacetylactis Bu2 citrate plasmid pSL2.

The replication region of the 7.8 kilobase (kb) citrate plasmid pSL2 from Lactococcus lactis ssp. lactis biovar. diacetylactis Bu2 was identified. Deletion derivatives of pSL2 were introduced into plasmid-free strain Bu2-60 and tested for their ability to replicate autonomously. The region necessary for replication was identified by comparison of the pSL2 derivatives, cloned and sequenced. No homologies were detected by comparing the putative Rep protein of pSL2 with replicons of other plasmids of Gram-positive bacteria. A part of an IS-element flanking the replication region was found.

Antimicrobial resistance and genomic characteristics of bovine Escherichia coli from five northern provinces of China.

BACKGROUND: Escherichia coli (E. coli) from food-producing animals serves as an important reservoir of antibiotic resistance genes (ARGs). T … es were classified as classical diarrheagenic E. coli based on virulence markers. Forty-one plasmid replicon types were identified, with IncFIB and IncHI2 being the most frequent and broadly distributed. The number of detected plasmid replicon types was positively associated with the number of ARGs and VFGs. CONCLUSIONS: This study provides foundational g …

IncN-R plasmid co-integration contributing to extensive drug resistance in Escherichia coli isolated from a canine prostatic abscess.

The emergence of multidrug-resistant (MDR) plasmids poses a significant global public health threat. This study characterized a novel multi-replicon IncN-R MDR plasmid pCUVET19-1426.1, harboring blaCTX-M-55 and 12 additional antimicrobial resistance genes (ARGs) in a newly identified Escherichia coli sequence type 13037, isolated from a canine prostatic abscess. Using antimicrobial resistance (AMR) profiling and genomic analysis, we elucidated the characteristics, evolution, and transferability of plasmid pCUVET19-1426.1, which contributed to the extensively drug-resistant phenotype of the bac…

SARS-CoV-2 resistance analyses from the Phase 3 PINETREE study of remdesivir treatment in nonhospitalized participants.

Remdesivir inhibits the SARS-CoV-2 RNA-dependent RNA polymerase (RdRp; Nsp12). Here, we conducted viral resistance analyses from the Phase 3 … ication complex proteins were phenotyped using site-directed mutagenesis in a SARS-CoV-2 subgenomic replicon system. Overall, emergent Nsp12 substitutions were detected in 8/115 (7.0%) remdesivir participants and 7/129 (5.4%) placebo participants (1 substitution overlap between groups). Based on a structural analysis, none of the emergent Nsp12 substitutio …

Characteristics of Extended-Spectrum β-Lactamase-Producing Escherichia coli Derived from Food and Humans in Northern Xinjiang, China.

This study aimed to investigate the drug resistance, molecular characteristics, and genetic relationship of extended-spectrum β-lactamase (E … to detect the resistance and virulence genes of ESBL-producing E. coli, and phylogenetics, plasmid replicon typing, screening of three integrons, and multilocus sequence typing (MLST) were performed. The results showed that 127 E. coli strains (15 human stool and 112 food samples) were isolated. Out of the 127 E. coli strains, 38 strains (6 human stool an …

Tripartite motif protein 52 (TRIM52) promoted fibrosis in LX-2 cells through PPM1A-mediated Smad2/3 pathway.

To investigate the roles of tripartite motif containing 52 (TRIM52) in human hepatic fibrosis in vitro, human hepatic stellate cell line LX-2 cells were transfected with hepatitis B virus (HBV) replicon to establish HBV-induced fibrosis in LX-2 cells, and then treated with small interfering RNA-mediated knockdown of TRIM52 (siTRIM52). LX-2 cells without HBV replicon transfection were treated with lentiviruses-mediated overexpression of TRIM52 and phosphatase magnesium dependent 1A (PPM1A). Fibrosis response of LX-2 cells were assessed by the production of hydroxyproline (Hyp) and collagen I/II…

Evaluation of antiviral drug synergy in an infectious HCV system.

BACKGROUND: Direct-acting antivirals (DAAs) have greatly improved the treatment of HCV infection. To improve response and prevent resistance, combination regimens have been the focus of clinical development. Regimens are often first assessed in vitro, with most combination studies to date using subgenomic replicon systems, which do not replicate the complete HCV life cycle and preclude study of entry and assembly inhibitors. Infectious full-length HCV systems have been developed and are being used to test drug efficacy. METHODS: Using cell-based HCV Con1b replicon and an infectious full-lengt…

Prospective One-Health investigation into low-abundant extended-spectrum β-lactamase producing Enterobacterales enables detection of potential dissemination events and persistence.

BACKGROUND: Following a one-health approach, we sought to determine reservoirs of extended-spectrum β-lactamase (ESBL)-producing Enterobacterales (ESBL-PE), other than Escherichia coli or Klebsiella pneumoniae complex species (i.e., low-abundant species), and their associated ESBL genes and plasmid-replicon profiles. METHODS: From 06/2017-05/2019, ESBL-PE isolates were recovered from clinical samples routinely collected at the University Hospital Basel (Basel, Switzerland), as well as from wastewater and foodstuffs collected monthly at predefined locations throughout the city of Basel. Whole-…