Project description:Among the multidrug-resistant (MDR) clones of Mycobacterium tuberculosis (Mtb) that were epidemiologically particularly successful, the 100-32 MDR Beijing clone, also called B0/W148 clone, has emerged since the early sixties. These B0/W148 strains belonging to the lineage 2 within the global Mtb phylogeny, are the main contributors to the MDR epidemic in Russia and Eastern Europe, and since the USSR’s fall, have also propagated to Western Europe. Among the various mutations that were identified as being specific for the MDR B0/W148 clone, we focused on two found in the transcriptional regulators KdpDE and WhiB6 and characterized in a H37Rv strain background the transcriptional profile associated with these mutations and their potential impact on the in vitro and in vivo growth characteristics.
Project description:Among the multidrug-resistant (MDR) clones of Mycobacterium tuberculosis (Mtb) that were epidemiologically particularly successful, the 100-32 MDR Beijing clone, also called B0/W148 clone, has emerged since the early sixties. These B0/W148 strains belonging to the lineage 2 within the global Mtb phylogeny, are the main contributors to the MDR epidemic in Russia and Eastern Europe, and since the USSR’s fall, have also propagated to Western Europe. Among the various mutations that were identified as being specific for the MDR B0/W148 clone, we focused on two found in the transcriptional regulators KdpDE and WhiB6 and characterized in a H37Rv strain background the transcriptional profile associated with these mutations and their potential impact on the in vitro and in vivo growth characteristics.
Project description:The spread of multidrug-resistant (MDR) bacteria, such as the skin commensal Staphylococcus aureus, is a worldwide heath challenge; therefore, new methods to counteract the over-colonization and virulence of opportunistic pathogenic biotypes are highly urgent. We characterized and compared the activity of Lacticaseibacillus rhamnosus LR06 (DSM 21981) and Lactobacillus johnsonii LJO02 (DSM 33828) cell-free supernatants (CFSs), produced in a conventional animal-based MRS medium and in an innovative vegetal TIL, versus the MDR Staphylococcus aureus (ATCC 43300). CFSs were analysed via high-resolution mass spectrometry and gas-chromatography for short chain fatty acids (SCFAs), lactic acid and protein composition, while their activity was assessed towards i) the viability and metabolic activity of the MRSA strain through optical density and alamarBlue assay, and ii) the capability to inhibit/disaggregate the pathogenic biofilm, via crystal violet staining. All the CFSs reduce viable and metabolically active S. aureus, with the TIL medium more efficient, respect to MRS, in stimulating lactic acid bacteria metabolism and reducing the virulent biofilm. CFSs from LJO02 produced in TIL are the best, thanks to specific SCFAs and proteic metabolites. In conclusion, antagonistic non-pathogenic CFSs represent a promising and strategic approach, with potential applications as bacteriotherapy, and bioremediation of hospital equipments surfaces.
Project description:The epidemic community-acquired methicillin-resistant S. aureus (CA-MRSA) clone USA300 has recently become a leading cause of hospital-associated bloodstream infections (BSI). Leveraging this recent introduction into hospitals and the limited genetic variation across the USA300 strains, we combined microbial comparative genomics with phenotypic analyses to discover adaptive mutations. USA300 isolates from BSI were found to have independently evolved single nucleotide variants in the transcriptional regulator sarZ. sarZ inactivation lead to altered expression of virulence factors, resulting in increased lethality in a murine model of BSI. Thus, USA300 strains can optimize their fitness in hospitals through evolution of higher virulence.
Project description:The aim of this experiment was to compare the transciptome of the peach-potato aphid (Myzus persicae) clone 4106a (a laboratory insecticide-susceptible standard collected from potato in Scotland in 2000) with clone 5191A (an insecticide resistant aphid clone collected from tobacco in Greece in 2007) to identify which genes are over or underexpressed in the resistant phenotype. Two-condition experiment, 4106a vs. 5191a Myzus persicae clones. Biological replicates: 4 pools of RNA extracted from ten 15 day old aphids of each clone. Technical Replicates: Two technical reps incorporating a dye swap. Total replication: eight replicates for each clone.
Project description:Purpose: Investigate whether maculopapular drug rash with COVID-19 infection (COVID19-MDR) exhibits a distinct gene expression in the skin as compared to non-COVID19-MDR. Methods:RNA was extracted from formalin-fixed, paraffin-embedded (FFPE) skin biopsies from COVID-MDR (n=3), MDR (n=7), and Healthy control (n=5). Library preparation for RNA-seq was performed by using the TruSeq Stranded RNA library preparation kit including polyA enrichment (Illumina) from total RNA. Sequencing was performed on the the Illumina NextSeq 500 platform with 75 cycles. Results: RNA sequencing from lesional skin showed that pathways of cytolysis and eosinophil chemotaxis were activated in COVID MDR. Cytolysis/cellular defense response related genes, such as PRF1 (perforin), GZMA (Granzyme A) and GNLY (Granulysin), as well as eosinophil migration/lymphocyte chemotaxis genes, e.g. C-C Motif chemokine ligand 5 (CCL5), CCL13, were upregulated in COVID MDR. Conclusions: This study provide an opportunity to understand the pathogenesis of MDR with the COVID-19 infection. We report the application of single-molecule-based sequencing technology for high-throughput profiling of histone modifications in mammalian cells. By obtaining over four billion bases of sequence from chromatin immunoprecipitated DNA, we generated genome-wide chromatin-state maps of mouse embryonic stem cells, neural progenitor cells and embryonic fibroblasts. We find that lysine 4 and lysine 27 trimethylation effectively discriminates genes that are expressed, poised for expression, or stably repressed, and therefore reflect cell state and lineage potential. Lysine 36 trimethylation marks primary coding and non-coding transcripts, facilitating gene annotation. Trimethylation of lysine 9 and lysine 20 is detected at satellite, telomeric and active long-terminal repeats, and can spread into proximal unique sequences. Lysine 4 and lysine 9 trimethylation marks imprinting control regions. Finally, we show that chromatin state can be read in an allele-specific manner by using single nucleotide polymorphisms. This study provides a framework for the application of comprehensive chromatin profiling towards characterization of diverse mammalian cell populations.