Staphylococcus aureus
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ABSTRACT:
PROVIDER: PRJDB10142 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Transcriptional profiling of the small colony variant (SCV) S. aureus isolate (JKD6229) compared to the parent isolate with a normal phenotype (JKD6210). Both isolates were from a patient with persistent S. aureus infection, and the SCV strain arose during failed antibiotic therapy.
2010-08-13 | GSE20957 | GEO
Project description:Transcriptional profiling of the small colony variant (SCV) S. aureus isolate (JKD6229) compared to the parent isolate with a normal phenotype (JKD6210). Both isolates were from a patient with persistent S. aureus infection, and the SCV strain arose during failed antibiotic therapy. Two condition experiment JKD6229 vs JKD6210. 4 biological replicates, one replicate per slide.
2010-08-13 | E-GEOD-20957 | biostudies-arrayexpress
Project description:Bacterial persister cells are phenotypic variants that exhibit a transient non-growing state and antibiotic tolerance. Here we provide in vitro evidence of Staphylococcus aureus persisters within infected host cells. We show that the bacteria surviving antibiotic treatment within host cells are persisters, displaying biphasic killing and reaching a uniformly non-responsive, non-dividing state when followed at the single-cell level. This phenotype is stable but reversible upon antibiotic removal. Intracellular S. aureus persisters remain metabolically active, but display an altered transcriptomic profile consistent with activation of stress responses, including the stringent response as well as cell-wall stress, SOS and heat-shock responses. These changes are associated with multidrug tolerance after exposure to a single antibiotic. We hypothesize that intracellular S. aureus persisters may constitute a reservoir for relapsing infection, and could contribute to therapeutic failures.
2020-03-25 | GSE139659 | GEO
Project description:S. aureus is a deadly pathogen due to its abilities to readily develop antibiotic resistance and evade our immune system. Antibiotic resistance in S. aureus is associated with reduced levels of neutrophil recruitment, which is a vital step in triggering an immune response to resolve infection. In this work, we report enhanced antibiotic agents that act as potential dual-function antibiotic-chemoattractants, enabling augmented neutrophil recruitment to S. aureus along with direct killing. Our agents exploit formylated peptides as chemoattractants for neutrophil recruitment, which is combined with the targeted binding of vancomycin to bacteria that generates a chemoattractant gradient for neutrophil recruitment. The combination of in vitro assays, cellular assays, infection-on-a-chip and in vivo mouse models, determined that these antibiotic-chemoattractants improve the recruitment, engulfment and killing of S. aureus by neutrophils. Furthermore, optimizing the fPep sequence can play an important role in the enhancement of neutrophil activity through differential activation of formyl peptide receptors. This offers an alternate approach in antibiotic development to overcome the threat of antibiotic resistance in the clinic.
2021-09-22 | PXD028332 | Pride
Project description:Staphylococcus aureus can cause severe invasive infections that require prolonged antibiotic treatment. Although S. aureus can easily acquire antibiotic resistance, even fully susceptible bacteria can persist and survive antibiotic therapy, thus complicating treatment. These so-called persisters are phenotypic variants of bacteria characterized by an arrested-growth phenotype that can tolerate high concentrations of chemotherapeutics and are associated with chronic and recurrent infections. Here, we show that S. aureus recovered directly from infection sites, displayed an increased bacterial lag-phase heterogeneity, forming more non-stable small colonies, indicating the presence of dormant bacteria. Infection modelling showed that host-mediated stress, including acidic pH, neutrophil exposure and murine abscesses, as well as antibiotic treatment, promoted formation of persisters both in vitro and in vivo. Proteomics and RNA-sequencing revealed molecular changes in bacteria in response to acidic stress leading to an overall more virulent population. However, after persister-enrichment, S. aureus displayed downregulation of pathways involved in virulence, cell division, and DNA replication, while ribosomal proteins, nucleotide-, and amino acid- metabolic pathways were upregulated, suggesting their requirement to fuel and maintain the persister phenotype. We demonstrate that decreased aconitase activity and ATP-levels as well as accumulation of insoluble proteins correlated with dormancy and growth reactivation cycles. Combination of antibiotics with retinoid derivatives, especially CD1530, significantly reduced both persisters and total bacterial load in a murine infection model. Our study provides an in-depth characterization of S. aureus persisters and shows that treatment failure due to antibiotic persistence could be addressed by using retinoid derivatives in combination with conventional antibiotics.
2021-09-09 | PXD018372 | Pride
Project description:Staphylococcus aureus can cause severe invasive infections that require prolonged antibiotic treatment. Although S. aureus can easily acquire antibiotic resistance, even fully susceptible bacteria can persist and survive antibiotic therapy, thus complicating treatment. These so-called persisters are phenotypic variants of bacteria characterized by an arrested-growth phenotype that can tolerate high concentrations of chemotherapeutics and are associated with chronic and recurrent infections. Here, we show that S. aureus recovered directly from infection sites, displayed an increased bacterial lag-phase heterogeneity, forming more non-stable small colonies, indicating the presence of dormant bacteria. Infection modelling showed that host-mediated stress, including acidic pH, neutrophil exposure and murine abscesses, as well as antibiotic treatment, promoted formation of persisters both in vitro and in vivo. Proteomics and RNA sequencing revealed stress-response reactions in bacteria leading to an overall more virulent population. However, after persister-enrichment, S. aureus displayed down-regulation of pathways involved in virulence, cell division, and DNA replication, while ribosomal proteins, nucleotide-, and amino acid- metabolic pathways were up-regulated, suggesting their requirement to fuel and maintain the persister phenotype. We demonstrate that decreased aconitase activity and ATP-levels as well as accumulation of insoluble proteins correlated with dormancy and growth reactivation cycles. Combination of antibiotics with retinoid derivatives, especially CD1530, significantly reduced both persisters and total bacterial load in a murine infection model. Our study provides an in-depth characterization of S. aureus persisters and shows that treatment failure due to antibiotic persistence could be addressed by using retinoid derivatives in combination with conventional antibiotics.
2021-02-12 | PXD018332 | Pride
Project description:Staphylococcus aureus causes invasive infections and easily acquires antibiotic resistances. Even antibiotic susceptible S. aureus can survive antibiotic therapy and persist, requiring prolonged treatment and surgical interventions. These so-called persisters display an arrested-growth phenotype, tolerate high antibiotic concentrations and are associated with chronic and recurrent infections. To characterize these persisters, we assessed S. aureus recovered directly from a patient suffering from a persistent infection. We show that host-mediated stress, including acidic-pH, abscesses-environment, and antibiotic exposure promoted persister formation in-vitro and in-vivo. Multi-omics analysis identified molecular changes in S. aureus in response to acid-stress leading to an overall virulent population. However, further analysis of a persister-enriched population revealed major molecular reprogramming in persisters including downregulation of virulence and cell division, and upregulation of ribosomal proteins, nucleotide-, and amino acid- metabolic pathways, suggesting their requirement to fuel and maintain the persister phenotype and highlighting that persisters are not completely metabolically inactive. Additionally, decreased aconitase activity and ATP-levels and accumulation of insoluble proteins involved in transcription, translation and energy-production correlated with persistence in S. aureus, underpinning the molecular mechanisms that drive the persister phenotype. Upon regrowth, these persisters regained their virulence potential and metabolically active phenotype including reduction of insoluble proteins, exhibiting a reversible state, crucial for recurrent infections. We further show that a targeted anti-persister combination therapy using retinoid derivatives and antibiotics significantly reduced lag-phase heterogeneity and persisters in a murine infection model. Our results provide molecular insights into persisters and help explain why persistent S. aureus infections are so difficult-to-treat.
2021-02-12 | PXD022858 | Pride
Project description:Methicillin-resistant Staphylococcus aureus (MRSA) is a major human pathogen in both community and health care settings, which causes a wide range of infections. Its resistance to β-lactam antibiotics and methicillin in particular, greatly complicates treatment options and success rate due to the limited number of antibiotics with activity against MRSA. To further the development of alternative therapeutics, the mechanisms that mediate antibiotic resistance in MRSA need to be fully understood. Cannabinoid compounds including cannabidiol (CBD), tetrahydrocannabinol (THC) and cannabinol (CBN) have shown promise as potential antibiotic adjuvants. In the present study, MRSA cells were subjected to antibiotic stress from methicillin in combination with three cannabinoid compounds, and subsequently analysed using metaproteomics to assess the metabolic response. Subjecting MRSA to methicillin made the cells more viable and increased their energy production, as well as upregulation of penicillin-binding protein 2 (PBP2). The cannabinoids all showed antimicrobial activity against MRSA, and inhibited the energy production of the cells as well as PBP2 when used in combination with methicillin. Furthermore, all three cannabinoid compounds inhibited resistance mechanisms in MRSA, resulting in a decrease in the minimum inhibitory concentration (MIC) of methicillin when used in combination.
2022-01-18 | PXD024244 | Pride
Project description:Staphylococcus aureus is a highly adaptable human pathogen; therefore a constant search for new effective antibiotic compounds is being preformed. Gene expression profiling can be used to determine potential targets and mechanisms of action (MOA) of known or potential drugs. The goal of our study was a development of a focused transcriptome platform to be used for confirming the MOA of new chemical entities which are designed as inhibitors of Mur ligases. A model transcriptional profile was set up for well described inhibitor of MurA ligase, fosfomycin. Moreover, we wanted to identify the pathways and processes primarily affected by this compound. S. aureus ATCC 29213 cells were treated with low concentrations of fosfomycin (1 and 4 µg/ml, respectively) and harvested at 10, 20 and 40 minutes after treatment, respectively. RNA was isolated, transcribed, labeled and hybridized to S. aureus GeneChips, representing approximately 3000 S. aureus genes. Using meta-analysis of our results and the results in the S. aureus microarray database, we have confirmed that fosfomycin induces “cell wall stimulon” genes and were able to identify genes and pathways specifically modulated by fosfomycin.
2009-03-26 | GSE15394 | GEO
Project description:We have previously shown that celecoxib, a selective COX-2 inhibitor, in combination with antibiotic sensitizes S aureus to antibiotic thereby decreasing the MIC of antibiotic. The present study is aimed at understanding the molecular mechanism of action of celecoxib on S aureus growth by microarray analysis. The results were analysed and the data clearly shows global change in the expression levels of S aureus genes in presence of celecoxib. Many virulence genes, essential genes and nonessential genes are down-regulated in presence of celecoxib in combination with ampicillin when compared to drug treatment alone.
2015-06-02 | GSE56100 | GEO