Identification of the genetic loci associating with the OMV formation by means of transcriptome analysis on the isogenic BF2766 mutants in B. fragilis strain YCH46
Ontology highlight
ABSTRACT:
ORGANISM(S): Bacteroides fragilis Bacteroides fragilis YCH46
PROVIDER: GSE69071 | GEO | 2016/02/21
SECONDARY ACCESSION(S): PRJNA284447
REPOSITORIES: GEO
Similar Datasets
Project description:The human gut microbe Bacteroides fragilis can alter the expression of its surface molecules such as capsular polysaccharides and SusC/SusD family outer membrane proteins through the reversible DNA inversions.ã??We have revealed that the outer membrane vesicle (OMV) formation in B. fragilis is regulated by BF2766 (tyrosine recombinase)-mediated DNA inversions at two distantly located promoter regions previously designated as class IV regions. In this study, we aimed to identify the genetic loci associating with the OMV formation by means of transcriptome analysis on the isogenic BF2766 mutants. By comparing the transciptomes of four BF2766 deletion mutants, in which the promoter orientations in class IV-1 and IV-2 regions were locked ON/ON, OFF/ON, OFF/OFF, or ON/OFF, we found that the transcription of the genes downstream of class IV-2 markedly elevated in a hyper-vesiculating ON/ON strain. A four chip study using total RNA isolated from four BF2766 deletion mutants culture. Each sample contains duplicated data.
2016-02-21 | E-GEOD-69071 | biostudies-arrayexpress
Project description:Microbial molecules have evolved to promote transient and/or permanent associations with mammals. Although numerous examples of secretion systems employed by pathogens have been described, mechanisms by which commensal bacteria export molecules during symbiosis remain unknown. The human gut mutualist Bacteroides fragilis produces a capsular polysaccharide (PSA) that directs host immune development. We reveal herein that outer membrane vesicles (OMVs) deliver PSA to dendritic cells (DCs), promoting regulatory T cells and inducing anti-inflammatory cytokines during protection from intestinal disease. In addition, we found that TLR2 signaling by DCs is required for OMV sensing. Following internalization into DCs and engagement of TLR2, OMVs initiate a gene expression program that results in IL-10 production by DCs. Although it is known that the outcome of PSA sensing by the immune system is Treg induction, nothing is known about the intracellular signaling pathway(s) activated by PSA within DCs. We analyzed the gene expression profile of DCs treated with OMVs to uncover factors that are expressed in a PSA-dependent, TLR2-dependent manner. Our findings demonstrate DC-induced protection from disease via OMV-delivery of a beneficial microbial molecule, uncovering a novel paradigm for inter-kingdom communication between the microbiota and mammals.
2012-07-23 | GSE39563 | GEO
Project description:Microbial molecules have evolved to promote transient and/or permanent associations with mammals. Although numerous examples of secretion systems employed by pathogens have been described, mechanisms by which commensal bacteria export molecules during symbiosis remain unknown. The human gut mutualist Bacteroides fragilis produces a capsular polysaccharide (PSA) that directs host immune development. We reveal herein that outer membrane vesicles (OMVs) deliver PSA to dendritic cells (DCs), promoting regulatory T cells and inducing anti-inflammatory cytokines during protection from intestinal disease. In addition, we found that TLR2 signaling by DCs is required for OMV sensing. Following internalization into DCs and engagement of TLR2, OMVs initiate a gene expression program that results in IL-10 production by DCs. Although it is known that the outcome of PSA sensing by the immune system is Treg induction, nothing is known about the intracellular signaling pathway(s) activated by PSA within DCs. We analyzed the gene expression profile of DCs treated with OMVs to uncover factors that are expressed in a PSA-dependent, TLR2-dependent manner. Our findings demonstrate DC-induced protection from disease via OMV-delivery of a beneficial microbial molecule, uncovering a novel paradigm for inter-kingdom communication between the microbiota and mammals. RNA samples (1ug total RNA) from BMDCs were labeled with fluorescent dyes using the Quick Amp Labeling Kit (Agilent). Microarray (AgilentWhole Mouse Genome chip) hybridizations (65M-BM-0C for 16 hours) and washes were performed with Agilent reagents following standard protocols. Microarrays were analyzed using an Agilent DNA Microarray Scanner G2565CA, and data were acquired using Agilent's Feature Extraction Software version 10.1.1.1. Significant genes were selected based on p< 0.01 and fold change >2.0.
2012-07-22 | E-GEOD-39563 | biostudies-arrayexpress
Project description:Bacterial outer membrane vesicles (OMVs) have important biological roles in pathogenesis and intercellular interactions, but a general mechanism of OMV formation is lacking. Here we show that the VacJ/Yrb ABC transport system, a proposed phospholipid (PL) transporter, is involved in OMV formation. Deletion or repression of VacJ/Yrb increases OMV production in two distantly related Gram-negative bacteria, Haemophilus influenzae and Vibrio cholerae. Within our studies we also analyzed the proteome of the OMV and outer membrane (OM) and found no massive alteration in Haemophilus influenzae Rd KW20, Rd ∆yrbE and Rd ∆vacJ. Lipidome analyses demonstrate that OMVs from VacJ/Yrb-defective mutants in H. influenzae are enriched in PLs and certain fatty acids. Furthermore, we demonstrate that OMV production and regulation of the VacJ/Yrb ABC transport system respond to iron starvation. Our results suggest a new general mechanism of OMV biogenesis based on PL accumulation in the outer leaflet of the outer membrane. This mechanism is highly conserved among Gram-negative bacteria, provides a means for regulation, can account for OMV formation under all growth conditions, and might have important pathophysiological roles in vivo.
2016-01-27 | PXD003249 | Pride
Project description:small RNA-Seq showing transfer of bacterial outer membrane vesicle (OMV) sRNA to host airway epithelial cells
| PRJNA318881 | ENA
Project description:Secretion of outer membrane vesicles (OMV) presents an important phenomenon in Gram-negative bacteria and they play multiple roles in their lifestyle including virulence and host-pathogen interaction. Francisella tularensis secretes unusually shaped tubular OMV. We here present a proteomic comparison of whole cell lysates, OMV and membrane fractions derived from two F. tularensis strains: a moderately virulent subsp. holarctica strain FSC200 and highly virulent subsp. tularensis SchuS4 strain. We describe a novel approach to the cross-species proteomic comparison based on creating an intersection protein database from the individual single-species databases. This approach proved to be less prone to quantification errors arising from differences in the protein sequences than using the individual databases. The consecutive comparison of the subproteomes of OMV and membranes of the two strains allowed us to distinguish the differences in protein amounts caused by global expression changes from those caused by preferential protein packing to OMV or membrane. Amongst the most different proteins we detected proteins involved in the biosynthesis and metabolism of the bacterial envelope components like O-antigen, lipid A, phospholipids, and fatty acids, as well as some of the major structural outer membrane proteins.
2021-02-08 | PXD022406 | Pride
Project description:Secretion of outer membrane vesicles (OMV) presents an important phenomenon in Gram-negative bacteria and they play multiple roles in their lifestyle including virulence and host-pathogen interaction. Francisella tularensis secretes unusually shaped tubular OMV filled with immunoreactive material and virulence factors. Mice were immunized with OMV isolated from Francisella tularensis subsp. holarctica, fully virulent strain FSC200. Their sera were then used for detection of immunoreactive proteins.
2024-02-22 | PXD047830 | Pride
Project description:Whole-genome DNA microarray analysis of Geobacter sulfurreducens cells grown on Fe(III)-oxide or Mn(IV)-oxide versus cells grown on soluble Fe(III) citrate indicated that there were significant differences in transcription patterns during growth on the insoluble metal oxides compared to growth on soluble Fe(III). Many of the genes that appeared to be up-regulated during growth on the metal hydroxides were involved in electron transport. The most highly up-regulated genes for both conditions were omcS and omcT, which encode co-transcribed c-type cytochromes exposed on the outer surface of the cell that are known to be required for Fe(III) and Mn(IV)-oxide reduction. Other electron transport genes that were up-regulated on both insoluble metals included the gene coding for the outer membrane c-type cytochrome, OmcG, genes for the outer membrane proteins, OmpB and OmpC, and the gene that codes for the structural protein of electrically conductive pili, PilA. Genes that were up-regulated in cells grown on Fe(III)-oxide but not Mn(IV)-oxide, included outer membrane c-type cytochromes including OmcE, a putative DMSO reductase protein, and proteins from the cytochrome bc1 complex. Electron transport genes that were only up-regulated in Mn(IV)-oxide grown cells included the genes that code for the outer membrane c-type cytochromes, OmcZ and OmcB, the periplasmic c-type cytochrome, MacA, and fumarate reductase. Genetic studies indicated that the c-type cytochrome proteins, PpcH, OmcJ, OmcM, OmcV, MacA, OmcF, OmcI, and OmcQ, and the iron sulfur subunit of the cytochrome b/b6 complex, QcrA, are important for reduction of insoluble Fe(III)-oxides but do not appear to be important for Mn(IV) reduction. These results demonstrate that the physiology of Fe(III) reducing bacteria differ significantly during growth on insoluble electron and soluble electron acceptors and emphasizes the importance of c-type cytochromes in extracellular electron transfer in G. sulfurreducens. Geobacter sulfurreducens cells were grown with acetate (5 mM) provided as the electron donor and either Fe(III) oxide or Fe(III) citrate provided as the electron acceptor. Cells were harvested at mid-log and total RNA was extracted. Total RNA (0.5 M-NM-<g) was amplified using the MessageAmp II-Bacteria Kit (Ambion, Foster City, CA) according to the manufacturers instructions. Ten micrograms of amplified RNA (aRNA) was chemically labeled with Cy3 (for the control or soluble electron acceptor condition) or Cy5 (for the experimental or insoluble electron acceptor condition) dye using the MicroMax ASAP RNA Labeling Kit (Perkin Elmer, Wellesley, MA) according to the manufacturerM-bM-^@M-^Ys instructions. RNA samples from three biological replicates were hybridized in duplicate on 12K Combimatrix antisense-detecting arrays. The experimental condition (DL1 grown with Mn(IV) oxide as acceptor) was labeled with cy5, the control condition (DL1 grown with Fe(III) citrate as acceptor) was labeled with cy3
2012-12-15 | E-GEOD-42919 | biostudies-arrayexpress
Project description:Whole-genome DNA microarray analysis of Geobacter sulfurreducens cells grown on Fe(III)-oxide or Mn(IV)-oxide versus cells grown on soluble Fe(III) citrate indicated that there were significant differences in transcription patterns during growth on the insoluble metal oxides compared to growth on soluble Fe(III). Many of the genes that appeared to be up-regulated during growth on the metal hydroxides were involved in electron transport. The most highly up-regulated genes for both conditions were omcS and omcT, which encode co-transcribed c-type cytochromes exposed on the outer surface of the cell that are known to be required for Fe(III) and Mn(IV)-oxide reduction. Other electron transport genes that were up-regulated on both insoluble metals included the gene coding for the outer membrane c-type cytochrome, OmcG, genes for the outer membrane proteins, OmpB and OmpC, and the gene that codes for the structural protein of electrically conductive pili, PilA. Genes that were up-regulated in cells grown on Fe(III)-oxide but not Mn(IV)-oxide, included outer membrane c-type cytochromes including OmcE, a putative DMSO reductase protein, and proteins from the cytochrome bc1 complex. Electron transport genes that were only up-regulated in Mn(IV)-oxide grown cells included the genes that code for the outer membrane c-type cytochromes, OmcZ and OmcB, the periplasmic c-type cytochrome, MacA, and fumarate reductase. Genetic studies indicated that the c-type cytochrome proteins, PpcH, OmcJ, OmcM, OmcV, MacA, OmcF, OmcI, and OmcQ, and the iron sulfur subunit of the cytochrome b/b6 complex, QcrA, are important for reduction of insoluble Fe(III)-oxides but do not appear to be important for Mn(IV) reduction. These results demonstrate that the physiology of Fe(III) reducing bacteria differ significantly during growth on insoluble electron and soluble electron acceptors and emphasizes the importance of c-type cytochromes in extracellular electron transfer in G. sulfurreducens. Geobacter sulfurreducens cells were grown with acetate (5 mM) provided as the electron donor and either Fe(III) oxide or Fe(III) citrate provided as the electron acceptor. Cells were harvested at mid-log and total RNA was extracted. Total RNA (0.5 M-NM-<g) was amplified using the MessageAmp II-Bacteria Kit (Ambion, Foster City, CA) according to the manufacturers instructions. Ten micrograms of amplified RNA (aRNA) was chemically labeled with Cy3 (for the control or soluble electron acceptor condition) or Cy5 (for the experimental or insoluble electron acceptor condition) dye using the MicroMax ASAP RNA Labeling Kit (Perkin Elmer, Wellesley, MA) according to the manufacturerM-bM-^@M-^Ys instructions. RNA samples from three biological replicates were hybridized in duplicate on 12K Combimatrix antisense-detecting arrays. The experimental condition (DL1 grown with Fe(III) oxide as acceptor) was labeled with cy5, the control condition (DL1 grown with Fe(III) citrate as acceptor) was labeled with cy3
2012-12-15 | E-GEOD-42918 | biostudies-arrayexpress
Project description:Whole-genome DNA microarray analysis of Geobacter sulfurreducens cells grown on Fe(III)-oxide or Mn(IV)-oxide versus cells grown on soluble Fe(III) citrate indicated that there were significant differences in transcription patterns during growth on the insoluble metal oxides compared to growth on soluble Fe(III). Many of the genes that appeared to be up-regulated during growth on the metal hydroxides were involved in electron transport. The most highly up-regulated genes for both conditions were omcS and omcT, which encode co-transcribed c-type cytochromes exposed on the outer surface of the cell that are known to be required for Fe(III) and Mn(IV)-oxide reduction. Other electron transport genes that were up-regulated on both insoluble metals included the gene coding for the outer membrane c-type cytochrome, OmcG, genes for the outer membrane proteins, OmpB and OmpC, and the gene that codes for the structural protein of electrically conductive pili, PilA. Genes that were up-regulated in cells grown on Fe(III)-oxide but not Mn(IV)-oxide, included outer membrane c-type cytochromes including OmcE, a putative DMSO reductase protein, and proteins from the cytochrome bc1 complex. Electron transport genes that were only up-regulated in Mn(IV)-oxide grown cells included the genes that code for the outer membrane c-type cytochromes, OmcZ and OmcB, the periplasmic c-type cytochrome, MacA, and fumarate reductase. Genetic studies indicated that the c-type cytochrome proteins, PpcH, OmcJ, OmcM, OmcV, MacA, OmcF, OmcI, and OmcQ, and the iron sulfur subunit of the cytochrome b/b6 complex, QcrA, are important for reduction of insoluble Fe(III)-oxides but do not appear to be important for Mn(IV) reduction. These results demonstrate that the physiology of Fe(III) reducing bacteria differ significantly during growth on insoluble electron and soluble electron acceptors and emphasizes the importance of c-type cytochromes in extracellular electron transfer in G. sulfurreducens. Geobacter sulfurreducens cells were grown with acetate (5 mM) provided as the electron donor and either Fe(III) oxide or Fe(III) citrate provided as the electron acceptor. Cells were harvested at mid-log and total RNA was extracted. Total RNA (0.5 μg) was amplified using the MessageAmp II-Bacteria Kit (Ambion, Foster City, CA) according to the manufacturers instructions. Ten micrograms of amplified RNA (aRNA) was chemically labeled with Cy3 (for the control or soluble electron acceptor condition) or Cy5 (for the experimental or insoluble electron acceptor condition) dye using the MicroMax ASAP RNA Labeling Kit (Perkin Elmer, Wellesley, MA) according to the manufacturer’s instructions.
2012-12-15 | GSE42919 | GEO