Staphylococcus aureus subsp. aureus JH9
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ABSTRACT:
PROVIDER: PRJNA15757 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Complete reconstitution of the vancomycin-intermediate Staphylococcus aureus (VISA) phenotype of Mu50 was achieved by sequentially introducing mutations into five genes of a vancomycin-susceptible S. aureus (VSSA) strain ∆IP. Introduction of mutation Ser329Leu into vraS encoding the sensor histidine kinase of vraSR two-component regulatory (TCR) system and another mutation Glu146Lys into msrR, encoding putative methionine sulfoxide reductase regulator, raised vancomycin resistance to the level of heterogeneously vancomycin-intermediate S. aureus (hVISA) strain Mu3. Introduction of two more mutations, graR (Asn197Ser) of graSR TCR system and rpoB(His481Tyr) encoding ß subunit of RNA polymerase, converted the hVISA strain into a VISA strain having the level of vancomycin resistance of Mu50. Surprisingly, however, the constructed quadruple mutant strain did not have thickened cell wall, a cardinal feature of VISA phenotype. Subsequent study showed that cell-wall thickening was an inducible phenotype with the mutant strain as opposed to that of Mu50, which is a constitutive one. Finally, introduction of mutation Ala297Val into the orf SAV2309 of the mutant strain converted the inducible cell-wall thickening into a constitutive one. SAV2309 encodes a putative formate dehydrogenase (designated Fdh2). Though not a transcription regulator, the mutation of the fdh2 caused a significant change in transcriptome. Thus, all of the five mutated genes required for VISA phenotype acquisition were directly or indirectly involved in the regulation of cell physiology. VISA seemed to be achieved through multiple genetic events accompanying drastic changes in cell physiology.
2016-04-19 | GSE43643 | GEO
Project description:To determine if significant genomic changes are associated with the development of vancomycin intermediate Staphylococcus aureus, genomic DNA microarrays were performed to compare the initial vancomycin susceptible Staphylococcus aureus (VSSA) and a related vancomycin intermediate Staphylococcus aureus (VISA) isolate from five unique patients (five isolate pairs). Keywords: comparative genomic hybridization
2006-11-03 | GSE5047 | GEO
Project description:In this study, we detected the first lysine succinylome and acetylome in a vancomycin-intermediate S. aureus (VISA) strain, XN108.Furthermore,Comparative analysis of the protein succinylation and acetylation between XN108-ΔcobB and XN108-WT strain was conducted on the basis of quantitative detection of both protein expression and protein modification
2022-11-09 | PXD030190 | Pride
Project description:The phenotype “intermediate vancomycin resistance” in Staphylococcus aureus (CLSI: MIC = 4-8 mg/L) has been assigned to changes that lead to alterations in cell wall synthesis and morphology. Most vancomycin intermediately resistant S. aureus (VISA) strains are characterised by an increased cell wall thickness as a consequence of an activated cell wall biosynthesis and decreased autolysis. The purpose of this study was to analyse the genetic basis of the vancomycin resistance mechanism of the clinical VISA isolate SA137/93A and its spontaneous mutant strain SA137/93G. The methicillin-resistant S. aureus (MRSA) SA137/93A was isolated from a tracheal secretion and displays heterogeneous intermediate vancomycin resistance (hVISA strain, MIC: 8 mg/L in BHI). Subculturing in presence of 6 mg/L vancomycin generated a mutant with homogeneous intermediate vancomycin resistance, that showed an MIC value of 16 mg/L in BHI and was designated SA137/93G. PFGE profiles and phage typing of the strains showed that they were members of the Iberian clone (ST247), which was prevalent in Germany in the early nineties under the designation “Northern German epidemic strain”. Both strains possess a thickened cell wall. However, the vancomycin resistance of strain SA137/93A is most probably enhanced by an increased amount of free D-Ala-D-Ala termini in the cell wall, which is due to decreased crosslinking, whereas the mutant strain SA137/93G shows normal crosslinking. Moreover, strain SA137/93A displays an increased expression of the essential two-component system yycFGHI as a consequence of an IS256 insertion in the promoter region, while strain SA137/93G is characterised by an insertion of IS256 into the gene tcaA. Although both insertions were shown to correlate with a decrease in susceptibility to vancomycin, the difference in the vancomycin resistance level of the strain pair could be mainly attributed to the disruption of tcaA in the mutant.This study was conducted to identify resistance mechanisms that both strains might have in common. To this end we compared the transcriptomes of both strains with that of the closely related vancomycin susceptible MRSA/VSSA strain SA1450/94 (MIC: 2 mg/L). We found that the genes of the capsule biosynthesis were the only genes with higher expression in both VISA strains. Keywords: strain comparison
2013-03-12 | GSE10529 | GEO
Project description:In this study, we detected the first lysine succinylome and acetylome in a vancomycin-intermediate S. aureus (VISA) strain, XN108.Furthermore,Comparative analysis of the protein succinylation and acetylation between XN108-ΔcobB and XN108-WT strain was conducted on the basis of quantitative detection of both protein expression and protein modification
2022-11-09 | PXD033341 | Pride
Project description:The lantibiotic mersacidin is an antimicrobial peptide of 20 amino acids that is ribosomally produced by Bacillus sp. strain HIL Y-85,54728. Mersacidin acts by complexing the sugar phosphate head group of the peptidoglycan precursor lipid II, thereby inhibiting the transglycosylation reaction of peptidoglycan biosynthesis. Here, we studied the transcriptomic response of S. aureus to subinhibitory concentrations of mersacidin using microarray and qRT-PCR techniques. The transcriptomics revealed an extensive induction of the cell wall stress response of S. aureus, which is partly controlled by the two-component regulatory system VraSR. In contrast to other cell wall-active antibiotics such as vancomycin, 0.2 x MIC of mersacidin was sufficient for induction. Interestingly, the cell wall stress response was equally induced in vancomycin intermediate resistant S. aureus (VISA) as well as in a highly susceptible strain. Furthermore, the efficiency of mersacidin was not affected by an increased cell wall thickness, which is part of the VISA-type resistance mechanism. Since the transcription of the VraDE ABC transporter genes was induced up to 1700-fold in our experiments, we analyzed the role of VraDE in the response of S. aureus to mersacidin. Unexpectedly, the deletion of the vraE gene did not result in an increased susceptibility to mersacidin compared to the wild type strain. In conclusion, mersacidin appears to be a strong inducer of the cell wall stress response of S. aureus at very low concentrations, which reflects its general mode of action as a cell wall-active peptide as well as its use of a unique target site on lipid II. Keywords: antibiotic induced response
2008-10-23 | GSE9261 | GEO
Project description:Coordinated protein-coding sequence transcriptional responses of Staphylococcus aureus to antimicrobial exposure are well described but little is known of the role of bacterial non-coding, small RNAs (sRNAs) in these responses. Here we used RNAseq to investigate the sRNA response of the epidemic multiresistant hospital ST239 S. Aureus strain JKD6009 and its vancomycin-intermediate clinical derivative, JKD6008, after exposure to four antibiotics representing the major classes of antimicrobials used to treat methicillin-resistant S. Aureus infections. These agents included vancomycin, linezolid, ceftobiprole, and tigecycline. We identified 410 potential sRNAs (sRNAs) and then compared global sRNA and mRNA expression profiles at 2 and 6 hours, without antibiotic exposure, and after exposure to 0.5 x MIC for each antibiotic, for both JKD6009 (VSSA), and JKD6008 (VISA).
2013-06-10 | GSE40864 | GEO
Project description:Vancomycin-intermediate Staphylococcus aureus (VISA) evolve in a strain-specific manner and acquire mutations that lead to alterations in cell wall metabolism that reduce susceptibility to vancomycin. We had earlier isolated several VISA mutant strains of the clinical hVISA strain MM66. This study is aimed at analyzing the metabolome of these mutants in comparison to the parent strain.
2016-01-12 | ST000309 | MetabolomicsWorkbench
Project description:Treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections is dependant on the efficacy of last-line antibiotics like vancomycin. Vancomycin treatment failure is most commonly linked to the emergence of vancomycin-intermediate resistance in clincal isolates (termed VISA). These isolates have not acquired resistance genes but appear to accumulate a heterogenous collection of single nucleotide polymerisms that collectively alter the physiology of the cell to increase vancomycin tolerance. Cell wall thickening is common among VISA isolates and is thought to decrease vancomycin permeability. Changes in regulatory sRNA expression have been correlated with antibiotic stress responses in VISA isolates however the functions of the vast majority of these RNA regulators is unknown. Here we have used the endoribonuclease RNase III to capture RNA-RNA interactions using an RNA proximity-dependant ligation technique termed CLASH. RNase III-CLASH uncovered hundreds of sRNA-mRNA interactions in vivo allowing functional characterisation of many sRNAs for the first time. Surprisingly, we find that an mRNA encoding an unusually long 3’UTR (here termed vigR) functions as a regulatory ‘hub’ within our RNA-RNA interaction network. We demonstrate vigR promotes expression of the cell wall lytic transglycosylase encoded by isaA through a direct mRNA-mRNA interaction. Further, we find that the vigR mRNA 3’UTR is required for cell wall thickening and that deletion of the vigR 3’UTR re-sensitises VISA to vancomycin. Our results demonstrate the utility of RNase III-CLASH for identifying new regulatory RNA functions and indicate that S. aureus may use mRNA-mRNA interactions to co-ordinate gene expression much more widely than previously appreciated.
2021-09-14 | GSE158830 | 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