Rhodomyrtone resistance in Staphylococcus aureus
Ontology highlight
ABSTRACT:
PROVIDER: PRJEB30619 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:To study the effect of Radix Paeoniae Rubra decoction on tolerance of Staphylococcus aureus.The effect of Radix Paeoniae Rubra on the resistance of Staphylococcus aureus to oxacillin sodium was studied by millipore dilution method in this experiment.At the same time ,conducted on transcriptome analysis of Staphylococcus aureus related genes in Radix Paeoniae Rubra.And to detect the expression level of related genes of Staphylococcus aureus under the action of Radix Paeoniae Rubra by PCR technology.The tolerance of Staphylococcus aureus was decreased obviously when the concentration of Radix Paeoniae Rubra decoction was above 1mg/ml.The effect of Radix Paeoniae Rubra decoction on the expression of tolerance genes femB,pvL and gluM when the concentration of Radix Paeoniae Rubra decoction was above 4mg/ml.When rhe concentration of Radix Paeoniae Rubra is more than 1mg/ml,it can effectively reduce the resistance of Staphylococcus aureus to oxacillin sodium.The reason may be due to the effect of Radix Paeoniae Rubra on the resistance gene of Staphylococcus aureus.
2021-01-30 | GSE165791 | GEO
Project description:Staphylococcus aureus is a notorious bacterial pathogen that causes a broad range of human diseases, and isolates that are resistant to several antibiotic classes including last resort antibiotics like vancomycin and daptomycin complicate the situation. We characterized S. aureus VC40, a strain that shows full resistance to vancomycin (MIC of 64 M-BM-5g/ml) and daptomycin (MIC of 4 M-BM-5g/ml) as well as a decreased susceptibility to further cell wall active agents. Genome sequencing revealed mutations in genes encoding the histidine kinases WalK and VraS that control cell envelope related processes and gene expression profiling indicated the induction of the respective regulons in strain VC40. Reconstitution of the mutations in walK or vraS into the susceptible S. aureus NCTC 8325 background resulted in a considerably increased resistance to vancomycin and daptomycin with MICs surpassing the clinical breakpoints for these antibiotics, thereby generating vancomycin-intermediate S. aureus (VISA) strains. As observed for S. aureus VC40, the walKwalk and vraS mutations also led to an increased expression of the respective regulons in the NCTC 8325 background. Phenotypic studies showed that S. aureus VC40 as well as the walKwalk and vraS mutants of strain NCTC 8325 were characterized by a significantly thickened cell wall, a decreased growth rate, a reduced autolytic activity and an increased resistance to lysostaphin-induced lysis. These results demonstrate that the WalK and VraS histidine kinases act as major switches which allow S. aureus to rapidly develop vancomycin resistance up to the VISA level via mutation of one single gene locus and concomitantly contribute to cross-resistance to other antibiotics including the last resort antibiotic daptomycin. Microarray was used to evaluate alteration in the transcriptome of mutS mutant and compared to the parental strain VC40
2014-08-18 | E-GEOD-46887 | biostudies-arrayexpress
Project description:The rise of antibiotic resistance in many bacterial pathogens has been driven by the spread of a few successful strains, suggesting that some bacteria are genetically pre-disposed to evolving resistance. We tested this hypothesis by challenging a diverse set of 222 strains of Staphylococcus aureus with the antibiotic ciprofloxacin in a large-scale evolution experiment. Surprisingly, we found that a single efflux pump, norA, causes widespread variation in evolvability across the diversity of S. aureus. In most lineages of S. aureus, elevated norA expression potentiated evolution by increasing the fitness benefit provided by resistance mutations in DNA topoisomerase under ciprofloxacin treatment. Amplification of norA provided a further mechanism of rapid evolution, but this was restricted to strains from CC398. Crucially, chemically inhibiting NorA effectively prevented the evolution of resistance across the diversity of S. aureus. Our study shows that the underlying genetic diversity of pathogenic bacteria plays a key role in shaping resistance evolution. Understanding this link makes it possible to predict which strains are likely to evolve resistance and to optimize inhibitor use to prevent this outcome.
2020-07-05 | GSE150762 | GEO
Project description:Staphylococcus aureus is a notorious bacterial pathogen that causes a broad range of human diseases, and isolates that are resistant to several antibiotic classes including last resort antibiotics like vancomycin and daptomycin complicate the situation. We characterized S. aureus VC40, a strain that shows full resistance to vancomycin (MIC of 64 µg/ml) and daptomycin (MIC of 4 µg/ml) as well as a decreased susceptibility to further cell wall active agents. Genome sequencing revealed mutations in genes encoding the histidine kinases WalK and VraS that control cell envelope related processes and gene expression profiling indicated the induction of the respective regulons in strain VC40. Reconstitution of the mutations in walK or vraS into the susceptible S. aureus NCTC 8325 background resulted in a considerably increased resistance to vancomycin and daptomycin with MICs surpassing the clinical breakpoints for these antibiotics, thereby generating vancomycin-intermediate S. aureus (VISA) strains. As observed for S. aureus VC40, the walKwalk and vraS mutations also led to an increased expression of the respective regulons in the NCTC 8325 background. Phenotypic studies showed that S. aureus VC40 as well as the walKwalk and vraS mutants of strain NCTC 8325 were characterized by a significantly thickened cell wall, a decreased growth rate, a reduced autolytic activity and an increased resistance to lysostaphin-induced lysis. These results demonstrate that the WalK and VraS histidine kinases act as major switches which allow S. aureus to rapidly develop vancomycin resistance up to the VISA level via mutation of one single gene locus and concomitantly contribute to cross-resistance to other antibiotics including the last resort antibiotic daptomycin.
2014-08-18 | GSE46887 | GEO
Project description:The epidemic character of community-associated methicillin resistant Staphylococcus aureus (CA-MRSA), especially the geographically widespread clone USA300, is poorly understood. USA300 isolates carry a type IV staphylococcal chromosomal cassette mec (SCCmec) element conferring -lactam antibiotic class resistance and a putative pathogenicity island, ACME (arginine catabolic mobile element). Physical linkage between SCCmec and ACME suggests that selection for antibiotic resistance and for pathogenicity may be interconnected. We constructed isogenic mutants containing deletions of SCCmec and ACME in a USA300 clinical isolate to determine the role of these elements in a rabbit model of bacteremia. We found that deletion of type IV SCCmec did not affect competitive fitness, whereas deletion of ACME significantly attenuated pathogenicity or fitness of USA300. These data are consistent with a model in which ACME enhances growth and survival of USA300, allowing for genetic "hitchhiking" of SCCmec. SCCmec in turn protects against exposure to β -lactams. Keywords: Wild type control vs mutant Wild type untreated in triplicate is compared to three mutants in triplicate in both exponential and stationary growth phases, totalling 24 samples
2010-05-19 | E-GEOD-9308 | biostudies-arrayexpress
Project description:The study aims to identify genes associated with oxacilin resistance. Staphylococcus aureus USA300 (also referred as 923) is used as reference strain through the whole study.
2011-04-08 | GSE26258 | GEO
Project description:The study aims to identify genes associated with oxacilin resistance. Staphylococcus aureus USA300 (also referred as 923) is used as reference strain through the whole study. 10 arrays total.
2011-04-08 | E-GEOD-26258 | biostudies-arrayexpress
Project description:The epidemic character of community-associated methicillin resistant Staphylococcus aureus (CA-MRSA), especially the geographically widespread clone USA300, is poorly understood. USA300 isolates carry a type IV staphylococcal chromosomal cassette mec (SCCmec) element conferring -lactam antibiotic class resistance and a putative pathogenicity island, ACME (arginine catabolic mobile element). Physical linkage between SCCmec and ACME suggests that selection for antibiotic resistance and for pathogenicity may be interconnected. We constructed isogenic mutants containing deletions of SCCmec and ACME in a USA300 clinical isolate to determine the role of these elements in a rabbit model of bacteremia. We found that deletion of type IV SCCmec did not affect competitive fitness, whereas deletion of ACME significantly attenuated pathogenicity or fitness of USA300. These data are consistent with a model in which ACME enhances growth and survival of USA300, allowing for genetic "hitchhiking" of SCCmec. SCCmec in turn protects against exposure to β -lactams. Keywords: Wild type control vs mutant
2008-09-30 | GSE9308 | GEO
Project description:Staphylococcus aureus is a worldwide pathogen that colonizes the human nasal cavity and is a major cause of respiratory and cutaneous infections. In the nasal cavity, S. aureus thrives with high concentrations of nitric oxide (NO) produced by the innate immune effectors and has available for growth slow metabolizing free hexoses, such as galactose. Here, we have used deep sequencing transcriptomic analysis (RNA-Seq) and 1H-NMR to uncover how S. aureus grown on galactose, a major carbon source present in the nasopharynx, survives the deleterious action of nitric oxide. We observed that, like on glucose, S. aureus withstands high concentrations of NO when using galactose. However, most likely this is achieved through a distinct metabolism that relies on the increased production of amino acids, such as glutamate, threonine and branched-chain amino acids. Moreover, we found that under these conditions the α-acetolactate synthase (ALS) enzyme, which converts pyruvate into α-acetolactate, plays a role in the resistance of S. aureus to NO. However, the role of ALS is not restricted to galactose but also extends to cells growing on glucose. The results suggest that ALS prevents intracellular acidification, promoting the production of branched-chain amino acids and activation of the TCA cycle. We show that ALS contributes to the successful infection of murine macrophages. Furthermore, ALS is also shown to contribute to the resistance of S. aureus to beta-lactam antibiotics such as methicillin and oxacillin.
2017-06-02 | GSE99563 | GEO
Project description:We have demonstrated previously that high-level resistance to nisin can occur in Staphylococcus aureus as a consequence of a single non-synonymous mutation in nsaS, which encodes a putative sensor kinase. To explore the mechanism by which this mutation confers high-level resistance we compared global transcriptomes of SH1000 and SH1000 (NsaS A208E) using RNAseq. This process identified several genes to be upregulated in SH1000 (NsaS A208E), including members of the NsaRS regulon which encode VraDE and BraDE, two putative ABC-transporters and are known to provide intrinsic nisin resistance. Gene deletion and complementation experiments revealed that both BraDE and VraDE are essential to high-level nisin resistance, with BraDE required for signal transduction through NsaRS, and VraDE directly responsible for nisin detoxification.
2018-11-19 | GSE114706 | GEO