Swarmer Cell Development of the Bacterium Proteus mirabilis Requires the Conserved Enterobacterial Common Antigen Biosynthesis Gene rffG
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ABSTRACT:
ORGANISM(S): Proteus mirabilis
PROVIDER: GSE116587 | GEO | 2018/07/04
REPOSITORIES: GEO
Similar Datasets
Project description:This series of microarrays compares gene expression by the bacterial pathogen Proteus mirabilis when the transcriptional regulator mrpJ is deleted or induced to levels found during experimental urinary tract infection. The enteric bacterium Proteus mirabilis is associated with a significant number of catheter-associated urinary tract infections. Strict regulation of the antagonistic processes of adhesion and motility, mediated by fimbriae and flagella, respectively, is essential for successful disease progression. Previously, the transcriptional regulator MrpJ, which is encoded by the mrp fimbrial operon, has been shown to repress both swimming and swarming motility. Here we show that MrpJ affects a wide array of cellular processes beyond adherence and motility. Microarray analysis found that expression of mrpJ mimicking expression levels that occur during UTI leads to differential expression of 217 genes related to, among others, bacterial virulence, type VI secretion and metabolism. We probed the molecular mechanism of transcriptional regulation through MrpJ using reporter assays and chromatin immunoprecipitation (ChIP). Two virulence-associated target genes, the flagellar master regulator flhDC and mrp itself, appear to be regulated through a binding site proximal to the transcriptional start, complemented by a more distantly situated enhancer site. Furthermore, an mrpJ deletion mutant colonized the bladders of mice at significantly lower levels in a transurethral model of infection. Additionally, we observe that mrpJ is widely conserved in a collection of recent clinical isolates, leading us to conclude that our results elucidate an unanticipated role of MrpJ as a global regulator of P. mirabilis virulence. Four biological replicates were analyzed for each set of arrays (P. mirabilis HI4320 wild type vs. ΔmrpJ, and vector pLX3607 vs. mrpJ plasmid pLX3805).
2015-04-13 | E-GEOD-63321 | biostudies-arrayexpress
Project description:This series of microarrays compares gene expression by the bacterial pathogen Proteus mirabilis when the transcriptional regulator mrpJ is deleted or induced to levels found during experimental urinary tract infection. The enteric bacterium Proteus mirabilis is associated with a significant number of catheter-associated urinary tract infections. Strict regulation of the antagonistic processes of adhesion and motility, mediated by fimbriae and flagella, respectively, is essential for successful disease progression. Previously, the transcriptional regulator MrpJ, which is encoded by the mrp fimbrial operon, has been shown to repress both swimming and swarming motility. Here we show that MrpJ affects a wide array of cellular processes beyond adherence and motility. Microarray analysis found that expression of mrpJ mimicking expression levels that occur during UTI leads to differential expression of 217 genes related to, among others, bacterial virulence, type VI secretion and metabolism. We probed the molecular mechanism of transcriptional regulation through MrpJ using reporter assays and chromatin immunoprecipitation (ChIP). Two virulence-associated target genes, the flagellar master regulator flhDC and mrp itself, appear to be regulated through a binding site proximal to the transcriptional start, complemented by a more distantly situated enhancer site. Furthermore, an mrpJ deletion mutant colonized the bladders of mice at significantly lower levels in a transurethral model of infection. Additionally, we observe that mrpJ is widely conserved in a collection of recent clinical isolates, leading us to conclude that our results elucidate an unanticipated role of MrpJ as a global regulator of P. mirabilis virulence.
2015-04-13 | GSE63321 | GEO
Project description:Proteus mirabilis is a leading cause of catheter-associated urinary tract infections (UTIs) and urolithiasis. The transcriptional regulator MrpJ inversely modulates two critical aspects of P. mirabilis UTI progression: fimbria-mediated attachment to the urinary tract, and flagella-mediated motility. Chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq) was used for the first time in a CAUTI pathogen to probe for in vivo direct targets of MrpJ. ChIP-seq revealed 81 78 direct MrpJ targets, including genes for motility, fimbriae and a type VI secretion system (T6SS), and the putative MrpJ binding sequence ACnCnnnnnnnGnGT.
2018-08-10 | GSE96042 | GEO
Project description:Swarming motility by the urinary tract pathogen Proteus mirabilis has been a long-studied, but little understood phenomenon. On agar, a P. mirabilis colony grows outward in a bullseye pattern formed by consecutive waves of rapid swarming followed by consolidation into shorter cells. To examine differential gene expression in these growth phases, a microarray, constructed based on the completed genome sequence and annotation, was undertaken. RNA from 1) broth-cultured, or 2) swarming cells was extracted to assess transcription during each of these growth states.
2010-06-07 | GSE17898 | GEO
Project description:Swarming motility by the urinary tract pathogen Proteus mirabilis has been a long-studied, but little understood phenomenon. On agar, a P. mirabilis colony grows outward in a bullseye pattern formed by consecutive waves of rapid swarming followed by consolidation into shorter cells. To examine differential gene expression in these growth phases, a microarray, constructed based on the completed genome sequence and annotation, was undertaken. RNA from 1) broth-cultured, or 2) consolidation-phase cells was extracted to assess transcription during each of these growth states.
2010-06-07 | GSE17897 | GEO
Project description:A resident of animal intestines, Proteus mirabilis is a major cause of catheter-associated urinary tract infections and can cause recurrent, persistent infections. Swarming, which is a collective behavior that promotes centimeter-scale population migration, is implicated in colonization of bladders and kidneys. A regulatory factor of swarming is kin recognition, which involves the transfer of a self-identity protein from one cell into a physically adjacent neighboring cell. However, how kin recognition regulates swarming was previously unclear. We have now shown a mechanism linking kin recognition, swarm migration, and antibiotics tolerance: cells induce a transient antibiotics-tolerant, persister-like state in adjacent non-identical cells which in turn prevents non-identical cells from continuing to participate in collective swarming. These affected non-identical cells continue to exhibit large-scale gene expression suggesting an active shift into a different expression state. These data provide two key insights for the field. First, kin recognition can be a regulatory mechanism that acts with spatial and temporal precision. Second, induction into an antibiotics-tolerant state, instead of occurring stochastically, can be physically and spatially regulated by neighboring cells. These insights highlight the importance of further developing four-dimensional (time and X-, Y-, Z-axes) model systems for interrogating cell-cell signaling and control in microbial populations.
2019-05-23 | GSE131647 | GEO
Project description:The enteric bacterium Proteus mirabilis is a common cause of complicated urinary tract infections. In the study, microrarrays were used to analyze P. mirabilis gene expression in vivo from experimentally infected mice. Urine was collected at 1, 3, and 7d postinfection, and RNA was isolated from bacteria in the urine for transcriptional analysis. Across 9 microarrays, 471 genes were upregulated and 82 were downregulated in vivo compared to in vitro broth culture. Genes upregulated in vivo encoded MR/P fimbriae, urease, iron uptake systems, amino acid and peptide transporters, pyruvate metabolism, and portions of the TCA cycle. Flagella were downregulated. Ammonia assimilation gene glnA (glutamine synthetase) was repressed in vivo while gdhA (glutamate dehydrogenase) was upregulated in vivo. Contrary to our expectations, ammonia availability due to urease activity in P. mirabilis did not drive this gene expression. A gdhA mutant was growth-deficient in minimal medium with citrate as the sole carbon source, and loss of gdhA resulted in a significant fitness defect in the mouse model of urinary tract infection. Unlike Escherichia coli, which represses gdhA and upregulates glnA in vivo and cannot utilize citrate, the data suggest that P. mirabilis uses glutamate dehydrogenase to monitor carbon-nitrogen balance, and this ability contributes to the pathogenic potential of P. mirabilis in the urinary tract. Voided urine from female CBA/J mice infected with Proteus mirabilis was collected and pooled in RNA stabilizing reagent (RNAprotect). Urine was collected at 1, 3, and 7 d postinfection. RNA was isolated from urine and log-phase LB cultures, converted to cDNA, and labeled with CyDye. Three arrays were completed per time point (9 arrays total). Slides were scanned with a ScanArray Express microarray scanner (Perkin Elmer) at 10 μm resolution and quantified using ScanArray Express software. Resulting data were normalized by total intensity and median spot intensities were identified using MIDAS (v. 2.22) software.
2011-11-29 | E-GEOD-25977 | biostudies-arrayexpress
Project description:The human gut acts as the main reservoir of microbes and a relevant source of life-threatening infections, especially in immunocompromised patients. There, the opportunistic fungal pathogen Candida albicans adapts to the host environment and additionally interacts with residing bacteria. We investigated fungal-bacterial interactions by coinfecting enterocytes with the yeast Candida albicans and the Gram-negative bacterium Proteus mirabilis resulting in enhanced host cell damage. This synergistic effect was conserved across different P. mirabilis isolates and occurred also with non-albicans Candida species and C. albicans mutants defective in filamentation or candidalysin production. Using bacterial deletion mutants, we identified the P. mirabilis hemolysin HpmA to be the key effector for host cell destruction. Spatially separated coinfections demonstrated that synergism between Candida and Proteus is induced by contact, but also by soluble factors. Specifically, we identified Candida-mediated glucose consumption and farnesol production as potential triggers for Proteus virulence. In summary, our study demonstrates that coinfection of enterocytes with C. albicans and P. mirabilis can result in increased host cell damage which is mediated by bacterial virulence factors as a result of fungal niche modification via nutrient consumption and production of soluble factors. This supports the notion that certain fungal-bacterial combinations have the potential to result in enhanced virulence in niches such as the gut and might therefore promote translocation and dissemination.
2022-05-09 | PXD031222 | Pride
Project description:Proteus mirabilis is an opportunistic pathogen that causes urinary tract infections in immunocompromised patients. Flagellar motility coupled with the ability to differentiate from short swimmer cells to highly elongated swarmer cells constitute key parts of the infection process. The mechanism by which the cells transduce the signal to differentiate remains unknown, but is believed to involve inhibition of flagellar rotation. Recent work has implicated FliL as a critical component of the signal transduction process, possibly through interactions with the motor proteins. The objective in the current study was to define the molecular mechanism underlying the cellâs ability to perceive a surface and begin the differentiation process, with a specific emphasis as to the role of FliL. Thus, the deep-sequencing technology of RNA-Seq was combined with genetic analysis to further examine the role of FliL in swarmer cell differentiation. RNA-Seq analysis of wild-type swarmer cells confirmed prior reports of genes involved in the differentiation process while concomittantly identifying novel genes potentially involved in swarming (including PMI1628, PMI0714-0716, and PMI0735, PMI0737, PMI0739, and PMI0740-0734). In comparison, RNA-Seq analysis of a fliL mutant showed that nearly all genes associated with the flagellar cascade and chemotaxis are repressed. A phenotypic, genetic, and transcriptomic characterization was then performed on spontaneous revertants of the fliL mutant, in which motility was restored yet still resulted in cells that differentiated under non-inducing (i.e. broth) conditions. Sequencing revealed perturbations in the C-terminus of FliL in both the mutant and revertant. Collectively, the data suggest that FliL senses the torque applied to the motor proteins- such as is encountered by a solid surface - and relays this signal to the master flagellar regulator FlhD4C2, triggering the expression of genes involved in the flagellar cascade. Transcriptomic comparison between wild-type Proteus mirabilis swarmer cells and a fliL mutant via RNA-Seq.
2011-11-15 | E-GEOD-30810 | biostudies-arrayexpress
Project description:The enteric bacterium Proteus mirabilis is a common cause of complicated urinary tract infections. In the study, microrarrays were used to analyze P. mirabilis gene expression in vivo from experimentally infected mice. Urine was collected at 1, 3, and 7d postinfection, and RNA was isolated from bacteria in the urine for transcriptional analysis. Across 9 microarrays, 471 genes were upregulated and 82 were downregulated in vivo compared to in vitro broth culture. Genes upregulated in vivo encoded MR/P fimbriae, urease, iron uptake systems, amino acid and peptide transporters, pyruvate metabolism, and portions of the TCA cycle. Flagella were downregulated. Ammonia assimilation gene glnA (glutamine synthetase) was repressed in vivo while gdhA (glutamate dehydrogenase) was upregulated in vivo. Contrary to our expectations, ammonia availability due to urease activity in P. mirabilis did not drive this gene expression. A gdhA mutant was growth-deficient in minimal medium with citrate as the sole carbon source, and loss of gdhA resulted in a significant fitness defect in the mouse model of urinary tract infection. Unlike Escherichia coli, which represses gdhA and upregulates glnA in vivo and cannot utilize citrate, the data suggest that P. mirabilis uses glutamate dehydrogenase to monitor carbon-nitrogen balance, and this ability contributes to the pathogenic potential of P. mirabilis in the urinary tract.
2011-11-29 | GSE25977 | GEO