Browse
Submit Data
Databases
API
Help

Dataset Information

22 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Bordetella pertussis fur gene restores iron repressibility of siderophore and protein expression to deregulated Bordetella bronchiseptica mutants.

ABSTRACT: We report the isolation and preliminary phenotypic characterization of manganese-resistant Bordetella bronchiseptica mutants with respect to deregulation of siderophore and iron-regulated protein expression. The fur gene of Bordetella pertussis was cloned by genetic complementation of this deregulated phenotype and confirmed as fur by nucleotide sequence analysis.

SUBMITTER: Brickman TJ

PROVIDER: S-EPMC176585 | biostudies-other | 1995 Jan

REPOSITORIES: biostudies-other

ACCESS DATA

Json Xml

Publications

Bordetella pertussis fur gene restores iron repressibility of siderophore and protein expression to deregulated Bordetella bronchiseptica mutants.

Brickman T J TJ Armstrong S K SK

Journal of bacteriology 19950101 1

We report the isolation and preliminary phenotypic characterization of manganese-resistant Bordetella bronchiseptica mutants with respect to deregulation of siderophore and iron-regulated protein expression. The fur gene of Bordetella pertussis was cloned by genetic complementation of this deregulated phenotype and confirmed as fur by nucleotide sequence analysis. ...[more]

PMID: 7798143

Similar Datasets

Conditional growth defect of Bordetella pertussis and Bordetella bronchiseptica ferric uptake regulator (fur) mutants.

Project description:Outer-membrane vesicles (OMVs) are promising tools in the development of novel vaccines against the respiratory pathogens Bordetella pertussis and Bordetella bronchiseptica. Unfortunately, vesiculation by bordetellae is too low for cost-effective vaccine production. In other bacteria, iron limitation or inactivation of the fur gene has been shown to increase OMV production, presumably by downregulation of the mla genes, which encode machinery for maintenance of lipid asymmetry in the outer membrane. Here, we followed a similar approach in bordetellae. Whereas a fur mutant was readily obtained in B. bronchiseptica, a B. pertussis fur mutant could only be obtained in iron-deplete conditions, indicating that a fur mutation is conditionally lethal in this bacterium. The fur mutants displayed a growth defect in iron-replete media, presumably because constitutive expression of iron-uptake systems resulted in iron intoxication. Accordingly, expression of the Escherichia coli ferritin FtnA to sequester intracellularly accumulated iron rescued the growth of the mutants in these media. The fur mutations led to the constitutive expression of novel vaccine candidates, such as the TonB-dependent receptors FauA for the siderophore alcaligin and BhuR for heme. However, neither inactivation of fur nor growth under iron limitation improved vesiculation, presumably because the expression of the mla genes appeared unaffected.

| S-EPMC9249403 | biostudies-literature

Identification of AlcR, an AraC-type regulator of alcaligin siderophore synthesis in Bordetella bronchiseptica and Bordetella pertussis.

Project description:A Fur titration assay was used to isolate DNA fragments bearing putative Fur binding sites (FBS) from a partial Bordetella bronchiseptica genomic DNA library. A recombinant plasmid bearing a 3.5-kb DNA insert was further studied. Successive deletions in the cloned fragment enabled us to map a putative FBS at about 2 kb from one end. Sequence analysis revealed the presence of an FBS upstream from a new gene encoding an AraC-type transcriptional regulator. The deduced protein displays similarity to PchR, an activator of pyochelin siderophore and ferripyochelin receptor synthesis in Pseudomonas aeruginosa. Homologous genes in Bordetella pertussis and Bordetella parapertussis were PCR amplified, and sequence comparisons indicated a very high conservation in the three species. The B. pertussis and B. bronchiseptica chromosomal genes were inactivated by allelic exchange. Under low-iron growth conditions, the mutants did not secrete the alcaligin siderophore and lacked AlcC, an alcaligin biosynthetic enzyme. Alcaligin production was restored after transformation with a plasmid bearing the wild-type gene. On the basis of its role in regulation of alcaligin biosynthesis, the new gene was designated alcR. Additional sequence determination showed that alcR is located about 2 kb downstream from the alcABC operon and is transcribed in the same orientation. Two tightly linked open reading frames, alcD and alcE, were identified between alcC and alcR. AlcE is a putative iron-sulfur protein; AlcD shows no homology with the proteins in the database. The production of major virulence factors and colonization in the mouse respiratory infection model are AlcR independent.

| S-EPMC106966 | biostudies-literature

Bordetella pertussis FbpA binds both unchelated iron and iron siderophore complexes.

Project description:Bordetella pertussis is the causative agent of whooping cough. This pathogenic bacterium can obtain the essential nutrient iron using its native alcaligin siderophore and by utilizing xeno-siderophores such as desferrioxamine B, ferrichrome, and enterobactin. Previous genome-wide expression profiling identified an iron repressible B. pertussis gene encoding a periplasmic protein (FbpABp). A previously reported crystal structure shows significant similarity between FbpABp and previously characterized bacterial iron binding proteins, and established its iron-binding ability. Bordetella growth studies determined that FbpABp was required for utilization of not only unchelated iron, but also utilization of iron bound to both native and xeno-siderophores. In this in vitro solution study, we quantified the binding of unchelated ferric iron to FbpABp in the presence of various anions and importantly, we demonstrated that FbpABp binds all the ferric siderophores tested (native and xeno) with ?M affinity. In silico modeling augmented solution data. FbpABp was incapable of iron removal from ferric xeno-siderophores in vitro. However, when FbpABp was reacted with native ferric-alcaligin, it elicited a pronounced change in the iron coordination environment, which may signify an early step in FbpABp-mediated iron removal from the native siderophore. To our knowledge, this is the first time the periplasmic component of an iron uptake system has been shown to bind iron directly as Fe(3+) and indirectly as a ferric siderophore complex.

| S-EPMC4075987 | biostudies-literature

RNAseq analyses of copper effect on Bordetella pertussis and Bordetella bronchiseptica

Project description:Copper is both essential and toxic to living beings, which therefore tightly control its intracellular concentration. At the host-pathogen interface, copper is used by phagocytic cells to kill invading microorganisms. We investigated copper homeostasis in the whooping cough agent Bordetella pertussis, which lives in the human respiratory mucosa and has no environmental reservoir. B. pertussis has considerably streamlined copper homeostasis mechanisms relative to other Gram-negative bacteria. Its single remaining defense line against copper intoxication consists in a metallochaperone diverted for copper passivation and two enzymes involved in peroxide detoxification, which together fight two stresses encountered in phagolysosomes. The three proteins are encoded by an original, composite operon assembled in an environmental ancestor and which is under sensitive control by copper. Interestingly, this system appears to play a role in persistent infection in the nasal cavity of B. pertussis-infected mice. Combining responses to co-occurring stresses in a tailored operon reveals a new strategy adopted by a host-restricted pathogen to optimize survival at minimal energy expenditure.

2020-10-27 | GSE145049 | GEO

Polymorphism of repeated regions of pertactin in Bordetella pertussis, Bordetella parapertussis, and Bordetella bronchiseptica.

Project description:Pertactin is an outer membrane protein expressed by Bordetella pertussis, Bordetella parapertussis, and Bordetella bronchiseptica that induces protective immunity to Bordetella infections. The immunodominant and immunoprotective epitopes of pertactin include two repeated regions, I and II. Comparison of these two repeated regions showed that B. parapertussis pertactin is invariant, whereas B. pertussis pertactin varies mostly in region I and B. bronchiseptica pertactin varies in both repeated regions I and II, but mostly in region II. These differences may result from specific characteristics of these Bordetella species.

| S-EPMC98445 | biostudies-literature

Bordetella pertussis and Bordetella bronchiseptica filamentous hemagglutinins are processed at different sites.

Project description:Filamentous hemagglutinin (FHA) mediates adherence and plays an important role in lower respiratory tract infections by pathogenic Bordetellae. The mature FHA proteins of B. pertussis (Bp-FHA) and the B. bronchiseptica (Bb-FHA) are generated by processing of the respective FhaB precursors by the autotransporter subtilisin-type protease SphB1. We have used bottom-up proteomics with differential 16O/18O labeling and show that despite high-sequence conservation of the corresponding FhaB segments, the mature Bp-FHA (~ 230 kDa) and Bb-FHA (~ 243 kDa) proteins are processed at different sites of FhaB, after the Ala-2348 and Lys-2479 residues, respectively. Moreover, protease surface accessibility probing by on-column (on-line) digestion of the Bp-FHA and Bb-FHA proteins yielded different peptide patterns, revealing structural differences in the N-terminal and C-terminal domains of the Bp-FHA and Bb-FHA proteins. These data indicate specific structural variations between the highly homologous FHA proteins.

| S-EPMC6070651 | biostudies-literature

Identification and characterization of iron-regulated Bordetella pertussis alcaligin siderophore biosynthesis genes.

Project description:Bordetella bronchiseptica mutants BRM1, BRM6, and BRM9 fail to produce the native dihydroxamate siderophore alcaligin. A 4.5-kb BamHI-Smal Bordetella pertussis genomic DNA fragment carried multiple genes required to restore alcaligin production to these siderophore-deficient mutants. Phenotypic complementation analysis using subclones of the 4.5-kb genomic region demonstrated that the closely linked BRM1 and BRM9 mutations were genetically separable from the BRM6 mutation, and both insertions exerted strong polar effects on expression of the downstream gene defined by the BRM6 mutation, suggesting a polycistronic transcriptional organization of these alcaligin biosynthesis genes. Subcloning and complementation experiments localized the putative Bordetella promoter to a 0.7-kb BamHI-SphI subregion of the cloned genomic DNA fragment. Nucleotide sequencing, phenotypic analysis of mutants, and protein expression by the 4.5-kb DNA fragment in Escherichia coli suggested the presence of three alcaligin system genes, namely, alcA, alcB, and alcC. The deduced protein products of alcA, alcB, and alcC have significant primary amino acid sequence similarities with known microbial siderophore biosynthesis enzymes. Primer extension analysis mapped the transcriptional start site of the putative alcaligin biosynthesis operon containing alcABC to a promoter region overlapping a proposed Fur repressor-binding site and demonstrated iron regulation at the transcriptional level.

| S-EPMC178270 | biostudies-other

Identification and characterization of alcR, a gene encoding an AraC-like regulator of alcaligin siderophore biosynthesis and transport in Bordetella pertussis and Bordetella bronchiseptica.

Project description:A Bordetella bronchiseptica iron transport mutant was isolated following an enrichment procedure based on streptonigrin resistance. The mutant displayed a growth defect on iron-restricted medium containing ferric alcaligin as the sole iron source. In addition to the apparent inability to acquire iron from the siderophore, the mutant failed to produce alcaligin as well as two known iron-regulated proteins, one of which is the AlcC alcaligin biosynthesis protein. A 1.6-kb KpnI-PstI Bordetella pertussis DNA fragment mapping downstream of the alcaligin biosynthesis genes alcABC restored both siderophore biosynthesis and expression of the iron-regulated proteins to the mutant. Nucleotide sequencing of this complementing 1.6-kb region identified an open reading frame predicted to encode a protein with strong similarity to members of the AraC family of transcriptional regulators, for which we propose the gene designation alcR. Primer extension analysis localized an iron-regulated transcription initiation site upstream of the alcR open reading frame and adjacent to sequences homologous to the consensus Fur repressor binding site. The AlcR protein was produced by using an Escherichia coli expression system and visualized in electrophoretic gels. In-frame alcR deletion mutants of B. pertussis and B. bronchiseptica were constructed, and the defined mutants exhibited the alcR mutant phenotype, characterized by the inability to produce and transport alcaligin and express the two iron-repressed proteins. The cloned alcR gene provided in trans restored these siderophore system activities to the mutants. Together, these results indicate that AlcR is involved in the regulation of Bordetella alcaligin biosynthesis and transport genes and is required for their full expression.

| S-EPMC106965 | biostudies-literature

Transcriptional profiling of the iron starvation response in Bordetella pertussis provides new insights into siderophore utilization and virulence gene expression.

Project description:Serological studies of patients with pertussis and the identification of antigenic Bordetella pertussis proteins support the hypothesis that B. pertussis perceives an iron starvation cue and expresses multiple iron source utilization systems in its natural human host environment. Furthermore, previous studies using a murine respiratory tract infection model showed that several of these B. pertussis iron systems are required for colonization and persistence and are differentially expressed over the course of infection. The present study examined genome-wide changes in B. pertussis gene transcript abundance in response to iron starvation in vitro. In addition to known iron source utilization genes, we identified a previously uncharacterized iron-repressed cytoplasmic membrane transporter system, fbpABC, that is required for the utilization of multiple structurally distinct siderophores including alcaligin, enterobactin, ferrichrome, and desferrioxamine B. Expression of type III secretion system genes was also found to be upregulated during iron starvation in both B. pertussis strain Tohama I and Bordetella bronchiseptica strain RB50. In a survey of type III secretion system protein production by an assortment of B. pertussis laboratory-adapted and low-passage clinical isolate strains, iron limitation increased the production and secretion of the type III secretion system-specific translocation apparatus tip protein Bsp22 in all Bvg-proficient strains. These results indicate that iron starvation in the infected host is an important environmental cue influencing not only Bordetella iron transport gene expression but also the expression of other important virulence-associated genes.

| S-EPMC3165686 | biostudies-literature

Oligosaccharide conjugates of Bordetella pertussis and bronchiseptica induce bactericidal antibodies, an addition to pertussis vaccine.

Project description:Pertussis is a highly contagious respiratory disease that is especially dangerous for infants and children. Despite mass vaccination, reported pertussis cases have increased in the United States and other parts of the world, probably because of increased awareness, improved diagnostic means, and waning vaccine-induced immunity among adolescents and adults. Licensed vaccines do not kill the organism directly; the addition of a component inducing bactericidal antibodies would improve vaccine efficacy. We investigated Bordetella pertussis and Bordetella bronchiseptica LPS-derived core oligosaccharide (OS) protein conjugates for their immunogenicity in mice. B. pertussis and B. bronchiseptica core OS were bound to aminooxylated BSA via their terminal Kdo residues. The two conjugates induced similar anti-B. pertussis LPS IgG levels in mice. B. bronchiseptica was investigated because it is easier to grow than B. pertussis. Using B. bronchiseptica genetically modified strains deficient in the O-specific polysaccharide, we isolated fractions of core OS with one to five repeats of the terminal trisaccharide, having at the nonreducing end a GlcNAc or GalNAc, and bound them to BSA at different densities. The highest antibody levels in mice were elicited by conjugates containing an average of 8-17 OS chains per protein and with one repeat of the terminal trisaccharide. Conjugate-induced antisera were bactericidal against B. pertussis, and the titers correlated with ELISA-measured antibody levels (r = 0.74). Such conjugates are easy to prepare and standardize; added to a recombinant pertussis toxoid, they may induce antibacterial and antitoxin immunity.

| S-EPMC3054038 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data