Regulation of flagellum biosynthesis in response to cell envelope stress in Salmonella Typhimurium
Ontology highlight
ABSTRACT:
ORGANISM(S): Salmonella enterica subsp. enterica serovar Typhimurium str. LT2
PROVIDER: GSE87447 | GEO | 2018/04/13
REPOSITORIES: GEO
Similar Datasets
Project description:Salmonella enterica serotype Typhimurium produces a variety of fimbrial appendages, among which the type 1 fimbriae is the most common type. In vitro static broth culture favors S. Typhimurium to produce type 1 fimbriae, while solid agar inhibits its expression. A transposon inserted in the stbC gene, which would encode an usher protein for Stb fimbriae of a non-flagellar S. Typhimurium LB5010 strain, conferred it to agglutinate yeast cells on both cultures, and was mannose-sensitive. Reverse transcription polymerase chain reaction (RT-PCR) revealed that the expression of the fimbrial major subunit gene fimA, and fimZ, a positive regulator gene of fimA, were both increased in the stbC mutant strain when grown on LB agar; fimW, a repressor gene of fimA, exhibited lower expression. Flagella were observed in the stbC mutant and this phenotype was correlated with the motile phenotype detected by MSRV agar medium and reaction with flagella antiserum. Microarray data and RT-PCR also indicated that the expression of three genes, motA, motB, and cheM, was enhanced in the stbC mutant. The S. Typhimurium stbC mutant was resistant to a variety of antibiotics, consistent with the finding that expression of yhcQ and ramA, two genes involved in multidrug resistance, was enhanced. A complementation test revealed that transforming a recombinant plasmid possessing the coding sequence of the stbC gene restored the mannose-sensitive agglutination phenotype to the stbC mutant much as that in the parental S. Typhimurium LB5010 strain, indicating the possibility of an interplay of different fimbrial systems in coordinating their expression. Key Words: Salmonella enterica serotype Typhimurium, fimbriae, type 1 fimbriae, stbC, transposon, multidrug resistant, flagella RNA transcript of Salmonella Typhimurium LB5010 strain comparing wild-type with stbC mutant. Two-cindition experiment, wild-type vs. stbC mutant strain.
2011-12-25 | E-GEOD-34685 | biostudies-arrayexpress
Project description:Background: Salmonella enterica serovar Typhimurium (S. Typhimurium) is a Gram-negative pathogen that must successfully adapt to the broad fluctuations in the concentration of dissolved dioxygen encountered in the host. In Escherichia coli, ArcA (Aerobic Respiratory Control) helps the cells to sense and respond to the presence of dioxygen. The global role of ArcA in E. coli is well characterized; however, little is known about its role in anaerobically grown S. Typhimurium. Results: We compared the transcriptional profiles of the virulent wild-type (WT) strain (ATCC 14028s) and its isogenic arcA mutant grown under anaerobic conditions. We found that ArcA directly or indirectly regulates 392 genes (8.5% of the genome); of these, 138 genes are poorly characterized. Regulation by ArcA in S. Typhimurium is similar, but distinct from that in E. coli. Thus, genes/operons involved in core metabolic pathways (e.g., succinyl-CoA, fatty acid degradation, cytochrome oxidase complexes, flagellar biosynthesis, motility, and chemotaxis) were regulated similarly in the two organisms. However, genes/operons present in both organisms, but regulated differently by ArcA in S. Typhimurium included those coding for ethanolamine utilization, lactate transport and metabolism, and succinate dehydrogenases. Salmonella-specific genes/operons regulated by ArcA included those required for propanediol utilization, flagellar genes (mcpAC, cheV), Gifsy-1 prophage genes, and a few SPI-3 genes (mgtBC, slsA, STM3784). In agreement with our microarray data, the arcA mutant was non-motile, lacked flagella, and was as virulent in mice as the WT. Furthermore, we identified a set of 120 genes whose regulation was shared with the anaerobic redox regulator, Fnr. Conclusion(s): We have identified the ArcA regulon in anaerobically grown S. Typhimurium. Our results demonstrated that in S. Typhimurium, ArcA serves as a transcriptional regulator coordinating cellular metabolism, flagella biosynthesis, and motility. Furthermore, ArcA and Fnr share in the regulation of 120 S. Typhimurium genes.
2011-02-10 | GSE24564 | GEO
Project description:Salmonella enterica serotype Typhimurium produces a variety of fimbrial appendages, among which the type 1 fimbriae is the most common type. In vitro static broth culture favors S. Typhimurium to produce type 1 fimbriae, while solid agar inhibits its expression. A transposon inserted in the stbC gene, which would encode an usher protein for Stb fimbriae of a non-flagellar S. Typhimurium LB5010 strain, conferred it to agglutinate yeast cells on both cultures, and was mannose-sensitive. Reverse transcription polymerase chain reaction (RT-PCR) revealed that the expression of the fimbrial major subunit gene fimA, and fimZ, a positive regulator gene of fimA, were both increased in the stbC mutant strain when grown on LB agar; fimW, a repressor gene of fimA, exhibited lower expression. Flagella were observed in the stbC mutant and this phenotype was correlated with the motile phenotype detected by MSRV agar medium and reaction with flagella antiserum. Microarray data and RT-PCR also indicated that the expression of three genes, motA, motB, and cheM, was enhanced in the stbC mutant. The S. Typhimurium stbC mutant was resistant to a variety of antibiotics, consistent with the finding that expression of yhcQ and ramA, two genes involved in multidrug resistance, was enhanced. A complementation test revealed that transforming a recombinant plasmid possessing the coding sequence of the stbC gene restored the mannose-sensitive agglutination phenotype to the stbC mutant much as that in the parental S. Typhimurium LB5010 strain, indicating the possibility of an interplay of different fimbrial systems in coordinating their expression. Key Words: Salmonella enterica serotype Typhimurium, fimbriae, type 1 fimbriae, stbC, transposon, multidrug resistant, flagella
2011-12-25 | GSE34685 | GEO
Project description:The long external filament of bacterial flagella is composed of several thousand copies of a single protein, flagellin. Here, we explore the role played by lysine methylation of flagellin in Salmonella, which requires the methylase FliB. We show that both flagellins of Salmonella enterica serovar Typhimurium, FliC and FljB, are methylated at surface-exposed lysine residues by FliB. A Salmonella Typhimurium mutant deficient in flagellin methylation is outcompeted for gut colonization in a gastroenteritis mouse model, and methylation of flagellin promotes bacterial invasion of epithelial cells in vitro. Lysine methylation increases the surface hydrophobicity of flagellin and enhances flagella-dependent adhesion of Salmonella to phosphatidylcholine vesicles and epithelial cells.
2020-04-27 | PXD017935 | Pride
Project description:Upon entering host cells, Salmonella quickly turn off flagella biogenesis to avoid recognition by the host immune system. However, it is not clear which host signal(s) Salmonella senses to initiate flagellum control.During the infection of a host,acid pH acts as an important environmental factor to triggers some genes expression. To investigate the effect of environmental acid signaling on the regulation of Salmonella flagella synthesis, we cultivated Salmonella typhimurium ATCC 14028s to an OD600 of 0.4, and then continued to culture for 2 h at pH 7.0 or pH 5.0. We then performed gene expression profiling analysis using data obtained from RNA-seq of cultured cells at different pH condition.
2022-08-06 | GSE210570 | GEO
Project description:Vibrio cholerae is highly motile by the action of a single polar flagellum. The loss of motility reduces the infectivity of V. cholerae, demonstrating that motility is an important virulence factor. FlrC is the sigma-54-dependent positive regulator of flagellar genes. Recently, the genes VC2206 (flgP) and VC2207 (flgO) were identified as being regulated by FlrC by microarray analysis of an flrC mutant. FlgP is reported to be an outer membrane lipoprotein required for motility that functions as a colonization factor. The study reported here focuses on the characterization of flgO, the first gene in the flgOP operon. We show FlgO/P are important for motility, as these mutants have reduced motility phenotypes. The flgO/P mutant populations display fewer motile cells as well as reduced numbers of flagellated cells. The flagella produced by the flgO/P mutant strains are shorter in length than the WT flagella, which can be restored by inhibiting rotation of the flagellum. FlgO is an outer membrane protein that localizes throughout the membrane and not at the flagellar pole. Although FlgO/P do not specifically localize to the flagellum, they are required for flagellar stability. Due to the nature of these motility defects, we established that the flagellum is not sufficient for adherence, rather, motility is the essential factor required for attachment and thus colonization by V. cholerae O1 of the classical biotype. This study reveals a novel mechanism for which the OMPs FlgO and FlgP function in motility to mediate flagellar stability and influence attachment and colonization. Vibrio cholerae O395 vs. rpoN mutant
2010-05-16 | E-GEOD-17144 | biostudies-arrayexpress
Project description:To explore the mechanisms of Salmonella desiccation resistance, we studied the transcriptomic responses in Salmonella Tennessee (Tennessee), using S. Typhimurium LT2 (LT2), a strain weakly resistant to desiccation, as a reference strain. In response to 2 h air-drying at 11% equilibrated relative humidity, approximately one-fourth of the ORFs in the Tennessee genome and one-fifth in LT2 were differentially expressed (> 2-fold). Among all differentially expressed functional groups (>5-fold) in both strains, the expression fold change associated with fatty acid metabolism was the highest, and constituted 51 and 35% of the total expression fold change in Tennessee and LT2, respectively. Tennessee showed greater changes in expression of genes associated with stress response and envelope modification than LT2, while showing lesser changes in protein biosynthesis expression. Expression of flagella genes was significantly more inhibited in stationary phase cells of Tennessee than LT2 both before and after desiccation.
2013-01-01 | GSE40146 | GEO
Project description:To explore the mechanisms of Salmonella desiccation resistance, we studied the transcriptomic responses in Salmonella Tennessee (Tennessee), using S. Typhimurium LT2 (LT2), a strain weakly resistant to desiccation, as a reference strain. In response to 2 h air-drying at 11% equilibrated relative humidity, approximately one-fourth of the ORFs in the Tennessee genome and one-fifth in LT2 were differentially expressed (> 2-fold). Among all differentially expressed functional groups (>5-fold) in both strains, the expression fold change associated with fatty acid metabolism was the highest, and constituted 51 and 35% of the total expression fold change in Tennessee and LT2, respectively. Tennessee showed greater changes in expression of genes associated with stress response and envelope modification than LT2, while showing lesser changes in protein biosynthesis expression. Expression of flagella genes was significantly more inhibited in stationary phase cells of Tennessee than LT2 both before and after desiccation. Salmonella Typhimurium LT2 ATCC strain 19585 (LT2) and Tennessee strain K4643 (Tennessee) were grown in TSB at 37 M-BM-:C with shaking for 20 h. Cells (~8 log CFU) for each strain were added on the discs and either stored at -80M-BM-:C directly, as control samples; or kept at 11% ERH at 25M-BM-0C for 2 h and then transferred into -80 M-BM-:C, as desiccation treated samples. Three independent experiments were carried out for each condition.
2013-01-01 | E-GEOD-40146 | biostudies-arrayexpress
Project description:Salmonella Typhimurium is an enteric food-borne pathogen responsible for causing salmonellosis associated with acute diarrhea. The bacterial invasion initially requires flagellar motility to reach the intestinal lumen and to cross the mucus layer of the intestinal epithelia and subsequent adhesion to the host cell, mainly mediated by fimbriae .The key genes involved in the pathogenic process are encoded within highly conserved regions of the bacterial genome called Salmonella Pathogenicity Islands (SPIs). The key regulator HilA, which is positively regulated by HilC and HilD, is located in SPI-1;however, other virulence-related regulators, such as RtsA, are encoded outside this island . During the invasion, proteins encoded by the prgHIJK, spaMNOPQRS, and invABCEFGH SPI-1 operons constitute a Type-3 Secretion System. Effector proteins,such as SipA and SipC (encoded in SPI-1) and SigD/SopB (encoded in SPI-5), translocate to the host cytosol through this system causing intracellular changes and inducing the immune response . The survival and replication of intracellular Salmonella inside Salmonella-containing vacuoles (SCVs) is mainly mediated by the genes located in SPI-2. The immune response is activated through the recognition of pathogen-associated molecular patterns (PAMPs) by specific receptors expressed on the surface and/or inside different cell types. The most important PAMPs are flagellin (monomers comprising the flagella filaments), particularly the FliC subunit, which is highly expressed on the bacterial surface, and lipopolysaccharide (LPS).Oxygen availability is limited in the inflamed gut whereas other compounds, such as hydrogen sulfide (H2S) and H2 are abundantly produced by the colonic bacteria. In addition, nutrients are also limited inside the SCV, while reactive oxygen as wellas nitrogen species may be found . In anaerobic conditions, Salmonella is able to survive by using alternative energy sources, such as nitrate or fumarate, through the use of specific enzymes: nitrate and nitrite reductases, fumarate reductase , DMSO reductase and respiratory hydrogenases.In a previous study, we compared transcriptomes of a clinical isolate of S. Typhimurium (strain 50-wt) and its derivative-multidrug-resistant mutant (strain 50-64) using microarrays . In addition to showing antimicrobial resistance, strain was also less invasive. In the present study, we focused on the genes of unknown function that showed impaired expression. We further selected those genes with a putative role in the acquired resistance phenotype or in the observed repressed virulence observed. Here, 4 putative membrane proteins and the yedF of unknown function were investigated to evaluate their involvement inthese two phenotypes.
2018-10-24 | PXD006825 | Pride
Project description:Vibrio cholerae is highly motile by the action of a single polar flagellum. The loss of motility reduces the infectivity of V. cholerae, demonstrating that motility is an important virulence factor. FlrC is the sigma-54-dependent positive regulator of flagellar genes. Recently, the genes VC2206 (flgP) and VC2207 (flgO) were identified as being regulated by FlrC by microarray analysis of an flrC mutant. FlgP is reported to be an outer membrane lipoprotein required for motility that functions as a colonization factor. The study reported here focuses on the characterization of flgO, the first gene in the flgOP operon. We show FlgO/P are important for motility, as these mutants have reduced motility phenotypes. The flgO/P mutant populations display fewer motile cells as well as reduced numbers of flagellated cells. The flagella produced by the flgO/P mutant strains are shorter in length than the WT flagella, which can be restored by inhibiting rotation of the flagellum. FlgO is an outer membrane protein that localizes throughout the membrane and not at the flagellar pole. Although FlgO/P do not specifically localize to the flagellum, they are required for flagellar stability. Due to the nature of these motility defects, we established that the flagellum is not sufficient for adherence, rather, motility is the essential factor required for attachment and thus colonization by V. cholerae O1 of the classical biotype. This study reveals a novel mechanism for which the OMPs FlgO and FlgP function in motility to mediate flagellar stability and influence attachment and colonization.
2009-07-18 | GSE17144 | GEO