Project description:Quorum sensing is a cell to cell communication process that involves chemical signaling. Yersinia pestis, the agent of plague, has two functional AHL quorum sensing systems Ysp and Ype. For several reasons, it was not clear what effect AHL pathways have on virulence gene expression and survival in the two different hosts, flea and human. To investigate to what effect AHL quorum sensing has on gene expression, we conducted microarray studies comparing Yersinia pestis CO92 (â??pgm) to a double AHL mutant strain (â??pgm Î?ypeIR) at 30°C. Six independent RNA samples from Y. pestis CO92 Î?pgm Î?ypeIR cultures were paired with six independent RNA samples from control Y. pestis CO92 R88 cultures for hybridization to six two-color microarrays. For three arrays, the control RNA sample was labeled with Alexa 555 dye and the experimental RNA sample was labeled with Alexa 647 dye; the dyes were reversed for the other three arrays to account for any dye bias.
Project description:Quorum sensing is a cell to cell communication process that involves chemical signaling. Yersinia pestis, the agent of plague, has two functional AHL quorum sensing systems Ysp and Ype. For several reasons, it was not clear what effect AHL pathways have on virulence gene expression and survival in the two different hosts, flea and human. To investigate to what effect Ysp AHL quorum sensing has on gene expression, we conducted microarray studies comparing Yersinia pestis CO92 (âpgm) to a single AHL mutant strain (âpgm ÎyspI) at 37°C. Six independent RNA samples from Y. pestis CO92 Îpgm ÎyspI cultures were paired with six independent RNA samples from control Y. pestis CO92 R88 cultures for hybridization to six two-color microarrays. For three arrays, the control RNA sample was labeled with Alexa 555 dye and the experimental RNA sample was labeled with Alexa 647 dye; the dyes were reversed for the other three arrays to account for any dye bias.
Project description:Quorum sensing is a cell to cell communication process that involves chemical signaling. Yersinia pestis, the agent of plague, has two functional AHL quorum sensing systems Ysp and Ype. For several reasons, it was not clear what effect AHL pathways have on virulence gene expression and survival in the two different hosts, flea and human. To investigate to what effect Ysp AHL quorum sensing has on gene expression, we conducted microarray studies comparing Yersinia pestis CO92 (âpgm) to a single AHL mutant strain (âpgm ÎyspI) at 30°C. Six independent RNA samples from Y. pestis CO92 Îpgm ÎyspI cultures were paired with six independent RNA samples from control Y. pestis CO92 R88 cultures for hybridization to six two-color microarrays. For three arrays, the control RNA sample was labeled with Alexa 555 dye and the experimental RNA sample was labeled with Alexa 647 dye; the dyes were reversed for the other three arrays to account for any dye bias.
Project description:The etiologic agent of bubonic plague, Yersinia pestis, senses cell density-dependent chemical signals to synchronize transcription between cells of the population in a process named quorum sensing. Though the closely related enteric pathogen Y. pseudotuberculosis uses quorum sensing system to regulate motility, the role of YpeIR quorum sensing in Y. pestis has been unclear. YpeIR is one of the AHL quorum sensing system in Y. pestis. In this study we performed transcriptional profiling experiments to identify Y. pestis YpeIR quorum sensing regulated functions at 37°C. Six independent RNA samples from Y. pestis CO92 Îpgm ÎypeIR cultures were paired with six independent RNA samples from control Y. pestis CO92 R88 cultures for hybridization to six two-color microarrays. For three arrays, the control RNA sample was labeled with Alexa 555 dye and the experimental RNA sample was labeled with Alexa 647 dye; the dyes were reversed for the other three arrays to account for any dye bias.
Project description:Quorum sensing is a cell to cell communication process that involves chemical signaling. Yersinia pestis, the agent of plague, has two functional AHL quorum sensing systems Ysp and Ype. For several reasons, it was not clear what effect AHL pathways have on virulence gene expression and survival in the two different hosts, flea and human. To investigate to what effect AHL quorum sensing has on gene expression, we conducted microarray studies comparing Yersinia pestis CO92 (âpgm) to a double AHL mutant strain (âpgm ÎypeIR ÎyspIR) at 37°C. Six independent RNA samples from Y. pestis CO92 R114 AHL deficient cultures were paired with six independent RNA samples from control Y. pestis CO92 R88 cultures for hybridization to six two-color microarrays. For three arrays, the control RNA sample was labeled with Alexa 555 dye and the experimental RNA sample was labeled with Alexa 647 dye; the dyes were reversed for the other three arrays to account for any dye bias.
Project description:The etiologic agent of bubonic plague, Yersinia pestis, senses cell density-dependent chemical signals to synchronize transcription between cells of the population in a process named quorum sensing. Though the closely related enteric pathogen Y. pseudotuberculosis uses quorum sensing system to regulate motility, the role of quorum sensing in Y. pestis has been unclear. In this study we performed transcriptional profiling experiments to identify Y. pestis quorum sensing regulated functions. Our analysis revealed that acyl-homoserine lactone based quorum sensing controls the expression of several metabolic functions. Maltose fermentation and the glyoxylate bypass are induced by acyl-homoserine lactone signaling. This effect was seen to be temperature conditional. Metabolism is unresponsive to quorum sensing regulation at mammalian body temperature, indicating a potential role for quorum sensing regulation of metabolism specifically during colonization of the flea vector. It is proposed that utilization of alternative carbon sources may enhance growth and/or survival during prolonged flea colonization, contributing to maintenance of plague in nature. Six independent RNA samples from Y. pestis CO92 R114 AHL deficient cultures were paired with six independent RNA samples from control Y. pestis CO92 R88 cultures for hybridization to six two-color microarrays. For three arrays, the control RNA sample was labeled with Alexa 555 dye and the experimental RNA sample was labeled with Alexa 647 dye; the dyes were reversed for the other three arrays to account for any dye bias.
Project description:The AI-2 quorum-sensing system has been linked to diverse phenotypes and regulatory changes in pathogenic bacteria. In strain CO92, the AI-2 signal is produced in a luxS-dependent manner, reaching maximal levels of 2.5 μM in late logarithmic growth, and both wild type and pigmentation mutant strains made equivalent levels of AI-2. Y. pestis CO92 possesses a chromosomal lsr locus encoding factors involved in the binding and import of AI-2, and confirming this assignment, an lsr deletion increased extracellular pools of AI-2. To assess the functional role of AI-2 sensing in Y. pestis, microarray study was conducted comparing the âPgm strain R88 to a âPgm âluxS mutant at 30°C to mimic the flea gut. Six independent RNA samples from Y. pestis CO92 ÎPgm cultures were paired with six independent RNA samples from ÎPgm ÎluxS cultures for hybridization to six two-color microarrays. A dye-swap design was used to remove the Cy5 and Cy3 dye bias.
Project description:The quorum-sensing system has been linked to diverse phenotypes and regulatory changes in pathogenic bacteria. In strain CO92, the AI-2 signal is produced in a luxS-dependent manner, reaching maximal levels of 2.5 μM in late logarithmic growth, and both wild type and pigmentation mutant strains made equivalent levels of AI-2. Yersinia pestis CO92 possesses a chromosomal lsr locus encoding factors involved in the binding and import of AI-2, and confirming this assignment, an lsr deletion increased extracellular pools of AI-2. To assess the functional role of 3 quorum sensing singlas in Y. pestis, microarray study was conducted comparing the 3 quorum sensing signals added in to control at 30°C to mimic the flea gut. Here, the ÎPgm (pigmentation-negative) R88 strain was used. The three signals are one AI-2 and two AHLs (N-(3-Oxooctanoyl)-L-homoserine lactone and N-Hexanoyl-DL-homoserine lactone).The control consisted of cells grown and treated under the same conditions without added signals. Six independent RNA samples from 3 signals add in cultures were paired with six independent RNA samples from control cultures for hybridization to six two-color microarrays. A dye-swap design was used to remove the Cy5 and Cy3 dye bias.
Project description:Temperature is a key environmental factor for facultative pathogens during the host adaptation response. To assess the functional role of temperature in Yersinia pestis, a microarray study was conducted comparing the Îpgm (pigmentation-negative) R88 strain grown at 37°C or 30°C. Six independent RNA samples from 37°C cultures were paired with six independent RNA samples from 30°C cultures for hybridization to six two-color microarrays. A dye-swap design was used to remove the Cy5 and Cy3 dye bias.
Project description:Yersinia pestis, the etiological agent of plague, is able to sense cell density by quorum sensing. The function of quorum sensing in Y. pestis is not clear. Here, the process of autoinducer-2 (AI-2) quorum sensing was investigated by comparing transcript profiles when AI-2 quorum-sensing signal is added in to control. The strain Îpgm (pigmentation-negative) mutant was used as wild type.The control consisted of cells grown and treated under the same conditions without added signals. Six independent RNA samples from Y. pestis CO92 Îpgm cultures were paired with six independent RNA samples from AI-2 signal added in cultures for hybridization to six two-color microarrays. A dye-swap design was used to remove the Cy5 and Cy3 dye bias.