Identification of determinants that allow maintenance of high-level fluoroquinolone resistance in .

is associated with multidrug-resistant infections in healthcare settings, with fluoroquinolones such as ciprofloxacin being currently ineffective. Clinical isolates largely harbor mutations in the GyrA and TopoIV fluoroquinolone targets, as well as mutations that increase expression of drug resistance-nodulation-division (RND) efflux pumps. Factors critical for maintaining fitness levels of pump overproducers are uncharacterized despite their prevalence in clinical isolates.

Diclofenac sensitizes multi-drug resistant Acinetobacter baumannii to colistin.

Acinetobacter baumannii causes life-threatening infections that are becoming difficult to treat due to increasing rates of multi-drug resistance (MDR) among clinical isolates. This has led the World Health Organization and the CDC to categorize MDR A. baumannii as a top priority for the research and development of new antibiotics.

Diclofenac sensitizes multi-drug resistant to colistin.

causes life-threatening infections that are becoming difficult to treat due to increasing rates of multi-drug resistance (MDR) among clinical isolates. This has led the World Health Organization and the CDC to categorize MDR as a top priority for the research and development of new antibiotics. Colistin is the last-resort antibiotic to treat carbapenem-resistant .

Identification of Determinants that Allow Maintenance of High-Level Fluoroquinolone Resistance in .

is associated with multidrug resistant (MDR) infections in healthcare settings, with fluoroquinolones such as ciprofloxacin being currently ineffective. Clinical isolates largely harbor mutations in the GyrA and TopoIV fluoroquinolone targets, as well as mutations that increase expression of drug resistance-nodulation-division (RND) efflux pumps. Factors critical for maintaining fitness levels of pump overproducers are uncharacterized despite their prevalence in clinical isolates.

Dual membrane-spanning anti-sigma factors regulate vesiculation in .

Bacteroidota are abundant members of the human gut microbiota that shape the enteric landscape by modulating host immunity and degrading dietary- and host-derived glycans. These processes are mediated in part by uter embrane esicles (OMVs). Here, we developed a high-throughput screen to identify genes required for OMV biogenesis and its regulation in ().

LptD depletion disrupts morphological homeostasis and upregulates carbohydrate metabolism in .

In a previous study, we identified an essential outer membrane protein (LptD) as an attractive target for development of novel antibiotics. Here, we characterized the effects of LptD depletion on physiology and morphology. An CRISPR interference (CRISPRi) strain was constructed to allow control of expression.

Dual Membrane-spanning Anti-Sigma Factors Regulate Vesiculation in Gut Bacteroidota.

Bacteroidota are abundant members of the human gut microbiota that shape the enteric landscape by modulating host immunity and degrading dietary- and host-derived glycans. These processes are at least partially mediated by O uter M embrane V esicles (OMVs). In this work, we developed a high-throughput screen to identify genes required for OMV biogenesis and its regulation in ( ).

Interspecies recombination, not de novo mutation, maintains virulence after β-lactam resistance acquisition in Streptococcus pneumoniae.

As opposed to de novo mutation, β-lactam resistance in S. pneumoniae is often conferred via homologous recombination during horizontal gene transfer. We hypothesize that β-lactam resistance in pathogenic streptococci is restricted to naturally competent species via intra-/interspecies recombination due to in vivo fitness trade-offs of de novo penicillin-binding protein (PBP) mutations.

Rapid, Multianalyte Detection of Opioid Metabolites in Wastewater.

By monitoring opioid metabolites, wastewater-based epidemiology (WBE) could be an excellent tool for real-time information on the consumption of illicit drugs. A key limitation of WBE is the reliance on costly laboratory-based techniques that require substantial infrastructure and trained personnel, resulting in long turnaround times. Here, we present an aptamer-based graphene field effect transistor (AptG-FET) platform for simultaneous detection of three different opioid metabolites.

Entropy of a bacterial stress response is a generalizable predictor for fitness and antibiotic sensitivity.

Current approaches explore bacterial genes that change transcriptionally upon stress exposure as diagnostics to predict antibiotic sensitivity. However, transcriptional changes are often specific to a species or antibiotic, limiting implementation to known settings only. While a generalizable approach, predicting bacterial fitness independent of strain, species or type of stress, would eliminate such limitations, it is unclear whether a stress-response can be universally captured.

Dielectrophoresis assisted rapid, selective and single cell detection of antibiotic resistant bacteria with G-FETs.

The rapid increase in antibiotic resistant pathogenic bacteria has become a global threat, which besides the development of new drugs, requires rapid, cheap, scalable, and accurate diagnostics. Label free biosensors relying on electrochemical, mechanical, and mass based detection of whole bacterial cells have attempted to meet these requirements. However, the trade-off between selectivity and sensitivity of such sensors remains a key challenge.

Plant-adapted Escherichia coli show increased lettuce colonizing ability, resistance to oxidative stress and chemotactic response.

Background: Escherichia coli is a widespread gut commensal and often a versatile pathogen of public health concern. E. coli are also frequently found in different environments and/or alternative secondary hosts, such as plant tissues.

Metabolic engineering of ammonium release for nitrogen-fixing multispecies microbial cell-factories.

The biological nitrogen fixation carried out by some Bacteria and Archaea is one of the most attractive alternatives to synthetic nitrogen fertilizers. In this study we compared the effect of controlling the maximum activation state of the Azotobacter vinelandii glutamine synthase by a point mutation at the active site (D49S mutation) and impairing the ammonium-dependent homeostatic control of nitrogen-fixation genes expression by the ΔnifL mutation on ammonium release by the cells. Strains bearing the single D49S mutation were more efficient ammonium producers under carbon/energy limiting conditions and sustained microalgae growth at the expense of atmospheric N2 in synthetic microalgae-bacteria consortia.

Genetic engineering of multispecies microbial cell factories as an alternative for bioenergy production.

There is currently much interest in developing technology to use microlgae or cyanobacteria for the production of bioenergy and biomaterials. Here, we summarize some remarkable achievements in strains improvement by traditional genetic engineering and discuss common drawbacks for further progress. We present general knowledge on natural microalgal-bacterial mutualistic interactions and discuss the potential of recent developments in genetic engineering of multispecies microbial cell factories.

Bioprospecting for fast growing and biomass characterization of oleaginous microalgae from South-Eastern Buenos Aires, Argentina.

As part of pioneering efforts to assess the potential of native microalgae as biofuel feedstock in South-Eastern Buenos Aires, 34 monoalgal cultures (corresponding to the Phylum Chlorophyta) were established and 21 were selected for further growth and biomass composition characterization. Novel RNA sequences in the ITS1-5.8S-ITS2 region were identified.

Association with an ammonium-excreting bacterium allows diazotrophic culture of oil-rich eukaryotic microalgae.

Concerns regarding the depletion of the world's reserves of oil and global climate change have promoted an intensification of research and development toward the production of biofuels and other alternative sources of energy during the last years. There is currently much interest in developing the technology for third-generation biofuels from microalgal biomass mainly because of its potential for high yields and reduced land use changes in comparison with biofuels derived from plant feedstocks. Regardless of the nature of the feedstock, the use of fertilizers, especially nitrogen, entails a potential economic and environmental drawback for the sustainability of biofuel production.