Project description:Autoinducer 2 (AI-2), a widespread by-product of the LuxS-catalyzed S-ribosylhomocysteine cleavage reaction in the activated methyl cycle, has been suggested to serve as an intra- and interspecies signaling molecule, but in many bacteria AI-2 control of gene expression is not completely understood. Particularly, we have a lack of knowledge about AI-2 signaling in the important human pathogens Staphylococcus aureus and S. epidermidis. Here, to determine the role of LuxS and AI-2 in S. epidermidis, we analyzed genome-wide changes in gene expression in an S. epidermidis luxS mutant and after addition of AI-2 synthesized by over-expressed S. epidermidis Pfs and LuxS enzymes. Genes under AI-2 control included mostly genes involved in sugar, nucleotide, amino acid, and nitrogen metabolism, but also virulence-associated genes coding for lipase and bacterial apoptosis proteins. In addition, we demonstrate by liquid chromatography/mass-spectrometry of culture filtrates that the pro-inflammatory phenol-soluble modulin (PSM) peptides, key virulence factors of S. epidermidis, are under luxS/AI-2 control. Our results provide a detailed molecular basis for the role of LuxS in S. epidermidis virulence and suggest a signaling function for AI-2 in this bacterium. Keywords: wild type without glucose control vs luxS mutant vs luxS mutant with auto-inducer II wild type without glucose control vs luxS mutant vs luxS mutant with auto-inducer II
Project description:Autoinducer 2 (AI-2), a widespread by-product of the LuxS-catalyzed S-ribosylhomocysteine cleavage reaction in the activated methyl cycle, has been suggested to serve as an intra- and interspecies signaling molecule, but in many bacteria AI-2 control of gene expression is not completely understood. Particularly, we have a lack of knowledge about AI-2 signaling in the important human pathogens Staphylococcus aureus and S. epidermidis. Here, to determine the role of LuxS and AI-2 in S. epidermidis, we analyzed genome-wide changes in gene expression in an S. epidermidis luxS mutant and after addition of AI-2 synthesized by over-expressed S. epidermidis Pfs and LuxS enzymes. Genes under AI-2 control included mostly genes involved in sugar, nucleotide, amino acid, and nitrogen metabolism, but also virulence-associated genes coding for lipase and bacterial apoptosis proteins. In addition, we demonstrate by liquid chromatography/mass-spectrometry of culture filtrates that the pro-inflammatory phenol-soluble modulin (PSM) peptides, key virulence factors of S. epidermidis, are under luxS/AI-2 control. Our results provide a detailed molecular basis for the role of LuxS in S. epidermidis virulence and suggest a signaling function for AI-2 in this bacterium. Keywords: wild type without glucose control vs luxS mutant vs luxS mutant with auto-inducer II
Project description:Biofilm-associated infection by the leading nosocomial pathogen Staphylococcus epidermidis is a major problem for the public health system. Here we used an especially discriminatory, two-step screen to discover key biofilm factors. We identified the transcriptional regulator and SarA paralog SarZ as a novel important determinant of biofilm formation and biofilm-associated infection by S. epidermidis. Notably, a sarZ mutant strain exhibited significantly reduced survival in two different models of biofilm-associated infection. Further, in addition to its significant influence on the transcription of the biosynthetic operon for S. epidermidis biofilm exopolysaccharide, sarZ impacted the expression of a series of virulence factors, including lipases and proteases. As a likely consequence of the regulated proteolytic activity, we observed increased resistance to an important human antimicrobial peptide, indicating a role for sarZ in the regulation of immune evasion. Interestingly, sarZ deficiency led to a hemolytic phenotype, a feature not commonly observed in S. epidermidis. Thus, our study indicates a key role for the SarZ regulator in maintaining the typical S. epidermidis phenotype, which is characterized by pronounced biofilm formation, immune evasion, and suppressed acute virulence, a likely reason for the success of S. epidermidis as a colonizer and pathogen in chronic, biofilm-associated infection. Keywords: Wild type control vs mutant
Project description:Biofilm-associated infection by the leading nosocomial pathogen Staphylococcus epidermidis is a major problem for the public health system. Here we used an especially discriminatory, two-step screen to discover key biofilm factors. We identified the transcriptional regulator and SarA paralog SarZ as a novel important determinant of biofilm formation and biofilm-associated infection by S. epidermidis. Notably, a sarZ mutant strain exhibited significantly reduced survival in two different models of biofilm-associated infection. Further, in addition to its significant influence on the transcription of the biosynthetic operon for S. epidermidis biofilm exopolysaccharide, sarZ impacted the expression of a series of virulence factors, including lipases and proteases. As a likely consequence of the regulated proteolytic activity, we observed increased resistance to an important human antimicrobial peptide, indicating a role for sarZ in the regulation of immune evasion. Interestingly, sarZ deficiency led to a hemolytic phenotype, a feature not commonly observed in S. epidermidis. Thus, our study indicates a key role for the SarZ regulator in maintaining the typical S. epidermidis phenotype, which is characterized by pronounced biofilm formation, immune evasion, and suppressed acute virulence, a likely reason for the success of S. epidermidis as a colonizer and pathogen in chronic, biofilm-associated infection. Keywords: Wild type control vs mutant Wild type untreated in triplicate is compared to SarZ mutant in triplicate
Project description:Staphylococcus aureus Newman and Staphylococcus epidermidis Tu3298, 20 minutes post challenge with sub-inhibitory concentration of sapienic acid vs equivalent concentration of ethanol. Challenge was added at mid logarithmic growth (OD600 0.5). Biological triplicates of samples were sequenced.
Project description:We sequenced mRNA from three independent biological replicates of Staphylococcus epidermidis biofilms with different proportion of dormant cells. Whole trancriptome analysis of Staphylococcus epidermidis biofilms with prevented and induced dormancy.
Project description:The custom-made S. epidermidis GeneChips(Shanghai Biochip Co., Ltd) included qualifiers representing open reading frame (ORF) sequences identified in the genomes of the S. epidermidis strain RP62A, as well as unique ORFs in S. epidermidis strain 12228. The GeneChips were composed of cDNA array containing PCR products of 2316 genes and oligonucleotide array containing 252 genes.Two-component regulatory systems (TCSs) play a pivotal role in bacterial adaptation, survival, and virulence by sensing changes in the external environment and modulating gene expression in response to a variety of stimuli.To investigate the regulatory role of LytSR, one of the TCSs identified in the genomes of S. epidermidis, we used the GeneChips to perform a transcriptional profile analysis of the wild strain and lytSR mutant. Wild type untreated in triplicate is compared to lytSR mutant in triplicate for cDNA array and four replicates on the oligo array.
Project description:We examined the differential gene expression of Staphylococcus epidermidis and Staphylococcus epidermidis in dual species biofilms. Therefore, we performed RNA-Seq on single and dual species biofilms and we compared the gene expression levels in dual species biofilms to those in single species biofilms.
Project description:We use the zebrafish embryo model to study the innate immune response against Staphylococcus epidermidis. Therefore, we injected S. epidermidis into the yolk at 2 hpf and took samples at 5 days post injection.
Project description:The custom-made S. epidermidis GeneChips(Shanghai Biochip Co., Ltd) included qualifiers representing open reading frame (ORF) sequences identified in the genomes of the S. epidermidis strain RP62A, as well as unique ORFs in S. epidermidis strain 12228. The GeneChips were composed of cDNA array containing PCR products of 2316 genes and oligonucleotide array containing 252 genes.Two-component regulatory systems (TCSs) play a pivotal role in bacterial adaptation, survival, and virulence by sensing changes in the external environment and modulating gene expression in response to a variety of stimuli.To investigate the regulatory role of LytSR, one of the TCSs identified in the genomes of S. epidermidis, we used the GeneChips to perform a transcriptional profile analysis of the wild strain and lytSR mutant.