Comparative proteome and transcriptome analyses of wild-type and live vaccine strains of Salmonella enterica serovar Gallinarum

ABSTRACT Three live vaccine candidates of Salmonella enterica subspecies I serotype Abortusovis (aroA, cya crp cdt, and plasmid-cured strains) have been developed, and their efficacies in inducing humoral antibodies and protecting against abortion after challenge with wild-type strain SS44 were evaluated in sheep. Following estrus synchronization, animals were immunized 3 weeks after fertilization and boosted once 3 weeks later. Following challenge with wild-type SS44, pregnancy failure of vaccinated ewes was reduced compared to that of nonimmunized controls. Attenuation of each vaccine was also assessed in challenge experiments with nonimmunized pregnant ewes and in BALB/c mice. All three vaccine candidates appear to be safe for use in sheep and provide a model for the development of live vaccine candidates against naturally occurring ovine salmonellosis.

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A network of Rab GTPases controls phagosome maturation and is modulated by Salmonella enterica serovar Typhimurium

The Journal of Cell Biology ◽

10.1083/jcb.200611056 ◽

2007 ◽

Vol 176 (3) ◽

pp. 263-268 ◽

Cited By ~ 107

Author(s):

Adam C. Smith ◽

Won Do Heo ◽

Virginie Braun ◽

Xiuju Jiang ◽

Chloe Macrae ◽

...

Keyword(s):

Salmonella Enterica ◽

Salmonella Enterica Serovar Typhimurium ◽

Dominant Negative ◽

Rab Gtpases ◽

Wild Type ◽

Intracellular Growth ◽

Non Invasive ◽

Serovar Typhimurium ◽

Guanosine Triphosphatase ◽

Kinetics Of

Members of the Rab guanosine triphosphatase (GTPase) family are key regulators of membrane traffic. Here we examined the association of 48 Rabs with model phagosomes containing a non-invasive mutant of Salmonella enterica serovar Typhimurium (S. Typhimurium). This mutant traffics to lysosomes and allowed us to determine which Rabs localize to a maturing phagosome. In total, 18 Rabs associated with maturing phagosomes, each with its own kinetics of association. Dominant-negative mutants of Rab23 and 35 inhibited phagosome–lysosome fusion. A large number of Rab GTPases localized to wild-type Salmonella-containing vacuoles (SCVs), which do not fuse with lysosomes. However, some Rabs (8B, 13, 23, 32, and 35) were excluded from wild-type SCVs whereas others (5A, 5B, 5C, 7A, 11A, and 11B) were enriched on this compartment. Our studies demonstrate that a complex network of Rab GTPases controls endocytic progression to lysosomes and that this is modulated by S. Typhimurium to allow its intracellular growth.

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OmpR and LeuO Positively Regulate the Salmonella enterica Serovar Typhi ompS2 Porin Gene

Journal of Bacteriology ◽

10.1128/jb.186.10.2909-2920.2004 ◽

2004 ◽

Vol 186 (10) ◽

pp. 2909-2920 ◽

Cited By ~ 39

Author(s):

Marcos Fernández-Mora ◽

José Luis Puente ◽

Edmundo Calva

Keyword(s):

Salmonella Enterica ◽

Type Strain ◽

Wild Type Strain ◽

Phosphorylation Site ◽

Regulatory Region ◽

Random Mutagenesis ◽

Fold Increase ◽

Upstream Regulatory Region ◽

Wild Type ◽

Transposon Insertion

ABSTRACT The Salmonella enterica serovar Typhi ompS2 gene codes for a 362-amino-acid outer membrane protein that contains motifs common to the porin superfamily. It is expressed at very low levels compared to the major OmpC and OmpF porins, as observed for S. enterica serovar Typhi OmpS1, Escherichia coli OmpN, and Klebsiella pneumoniae OmpK37 quiescent porins. A region of 316 bp, between nucleotides −413 and −97 upstream of the transcriptional start point, is involved in negative regulation, as its removal resulted in a 10-fold increase in ompS2 expression in an S. enterica serovar Typhi wild-type strain. This enhancement in expression was not observed in isogenic mutant strains, which had specific deletions of the regulatory ompB (ompR envZ) operon. Furthermore, ompS2 expression was substantially reduced in the presence of the OmpR D55A mutant, altered in the major phosphorylation site. Upon random mutagenesis, a mutant where the transposon had inserted into the upstream regulatory region of the gene coding for the LeuO regulator, showed an increased level of ompS2 expression. Augmented expression of ompS2 was also obtained upon addition of cloned leuO to the wild-type strain, but not in an ompR isogenic derivative, consistent with the notion that the transposon insertion had increased the cellular levels of LeuO and with the observed dependence on OmpR. Moreover, LeuO and OmpR bound in close proximity, but independently, to the 5′ upstream regulatory region. Thus, the OmpR and LeuO regulators positively regulate ompS2.

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The Capsule Encoding the viaB Locus Reduces Interleukin-17 Expression and Mucosal Innate Responses in the Bovine Intestinal Mucosa during Infection with Salmonella enterica Serotype Typhi

Infection and Immunity ◽

10.1128/iai.01571-06 ◽

2007 ◽

Vol 75 (9) ◽

pp. 4342-4350 ◽

Cited By ~ 69

Author(s):

Manuela Raffatellu ◽

Renato L. Santos ◽

Daniela Chessa ◽

R. Paul Wilson ◽

Sebastian E. Winter ◽

...

Keyword(s):

Mouse Model ◽

Salmonella Enterica ◽

Intestinal Inflammation ◽

Fluid Secretion ◽

Interleukin 17 ◽

Loop Model ◽

Wild Type ◽

Ileal Loop ◽

Chemokine Production

ABSTRACT The viaB locus contains genes for the biosynthesis and export of the Vi capsular antigen of Salmonella enterica serotype Typhi. Wild-type serotype Typhi induces less CXC chemokine production in tissue culture models than does an isogenic viaB mutant. Here we investigated the in vivo relevance of these observations by determining whether the presence of the viaB region prevents inflammation in two animal models of gastroenteritis. Unlike S. enterica serotype Typhimurium, serotype Typhi or a serotype Typhi viaB mutant did not elicit marked inflammatory changes in the streptomycin-pretreated mouse model. In contrast, infection of bovine ligated ileal loops with a serotype Typhi viaB mutant resulted in more fluid accumulation and higher expression of the chemokine growth-related oncogene alpha (GROα) and interleukin-17 (IL-17) than did infection with the serotype Typhi wild type. There was a marked upregulation of IL-17 expression in both the bovine ligated ileal loop model and the streptomycin-pretreated mouse model, suggesting that this cytokine is an important component of the inflammatory response to infection with Salmonella serotypes. Introduction of the cloned viaB region into serotype Typhimurium resulted in a significant reduction of GROα and IL-17 expression and in reduced fluid secretion. Our data support the idea that the viaB region plays a role in reducing intestinal inflammation in vivo.

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Intranasal Interleukin-12 Treatment for Protection against Respiratory Infection with the Francisella tularensis Live Vaccine Strain

Infection and Immunity ◽

10.1128/iai.73.4.2306-2311.2005 ◽

2005 ◽

Vol 73 (4) ◽

pp. 2306-2311 ◽

Cited By ~ 67

Author(s):

Nathalie S. Duckett ◽

Sofia Olmos ◽

Douglas M. Durrant ◽

Dennis W. Metzger

Keyword(s):

Respiratory Infection ◽

Francisella Tularensis ◽

Vaccine Strain ◽

Live Vaccine ◽

Interleukin 12 ◽

Live Vaccine Strain ◽

Wild Type ◽

Intranasal Infection ◽

Ifn Γ

ABSTRACT Francisella tularensis is a gram-negative intracellular bacterium that can induce lethal respiratory infection in humans and rodents. However, little is known about the role of innate or adaptive immunity in protection from respiratory tularemia. In the present study, the role of interleukin-12 (IL-12) in inducing protective immunity in the lungs against intranasal infection of mice with the live vaccine strain (LVS) of F. tularensis was investigated. It was found that gamma interferon (IFN-γ) and IL-12 were strictly required for protection, since mice deficient in IFN-γ, IL-12 p35, or IL-12 p40 all succumbed to LVS doses that were sublethal for wild-type mice. Furthermore, exogenous IL-12 treatment 24 h before intranasal infection with a lethal dose of LVS (10,000 CFU) significantly decreased bacterial loads in the lungs, livers, and spleens of wild-type BALB/c and C57BL/6 mice and allowed the animals to survive infection; such protection was not observed in IFN-γ-deficient mice. The resistance induced by IL-12 to LVS infection was still observed in NK cell-deficient beige mice but not in CD8−/− mice. These results demonstrate that exogenous IL-12 delivered intranasally can prevent respiratory tularemia through a mechanism that is at least partially dependent upon the expression of IFN-γ and CD8 T cells.

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Virulence and Metabolic Characteristics of Salmonella enterica Serovar Enteritidis Strains with DifferentsefDVariants in Hens

Applied and Environmental Microbiology ◽

10.1128/aem.00852-12 ◽

2012 ◽

Vol 78 (18) ◽

pp. 6405-6412 ◽

Cited By ~ 6

Author(s):

Cesar A. Morales ◽

Jean Guard ◽

Roxana Sanchez-Ingunza ◽

Devendra H. Shah ◽

Mark Harrison

Keyword(s):

Salmonella Enterica ◽

Egg Production ◽

The Body ◽

Wild Type ◽

Salmonella Enterica Serovar Enteritidis ◽

Blood Calcium ◽

Content Type ◽

Metabolic Characteristics ◽

Wide Range ◽

Metabolic Properties

ABSTRACTSalmonella entericaserovar Enteritidis is one of a fewSalmonella entericaserotypes that has SEF14 fimbriae encoded by thesefoperon, which consists of 4 cotranscribed genes,sefABCD, regulated bysefR. A parental strain was used to construct asefDmutant and its complement, and all 3 strains were compared for gene expression, metabolic properties, and virulence characteristics in hens. Transcription ofsefDby wild type was suppressed at 42°C and absent for the mutant under conditions where the complemented mutant had 103times higher transcription. Growth of the complemented mutant was restricted in comparison to that of the mutant and wild type. Hens infected with the wild type and mutant showed decreased blood calcium and egg production, but infection with the complemented mutant did not. Thus, the absence ofsefDcorrelated with increased metabolic capacity and enhanced virulence of the pathogen. These results suggest that any contribution thatsefDmakes to egg contamination is either unknown or would be limited to early transmission from the environment to the host. Absence ofsefD, either through mutation or by suppression of transcription at the body temperature of the host, may contribute to the virulence ofSalmonella entericaby facilitating growth on a wide range of metabolites.

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Evaluation of the live vaccine efficacy of virulence plasmid-cured, and phoP- or aroA-deficient Salmonella enterica serovar Typhimurium in mice

Journal of Veterinary Medical Science ◽

10.1292/jvms.14-0013 ◽

2015 ◽

Vol 77 (2) ◽

pp. 181-186 ◽

Cited By ~ 7

Author(s):

Hidenori MATSUI ◽

Yasunori ISSHIKI ◽

Masahiro EGUCHI ◽

Yohsuke OGAWA ◽

Yoshihiro SHIMOJI

Keyword(s):

Vaccine Efficacy ◽

Salmonella Enterica ◽

Live Vaccine ◽

Virulence Plasmid ◽

Serovar Typhimurium

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Salmonella enterica Serovar Typhimurium Uses PbgA/YejM To Regulate Lipopolysaccharide Assembly during Bacteremia

Infection and Immunity ◽

10.1128/iai.00758-19 ◽

2019 ◽

Vol 88 (1) ◽

Cited By ~ 16

Author(s):

Melina B. Cian ◽

Nicole P. Giordano ◽

Revathi Masilamani ◽

Keaton E. Minor ◽

Zachary D. Dalebroux

Keyword(s):

Salmonella Enterica ◽

Lipid A ◽

Salmonella Enterica Serovar Typhimurium ◽

Transmembrane Domain ◽

Wild Type ◽

Content Type ◽

Serovar Typhimurium ◽

Periplasmic Domain ◽

Inner Membrane Protein ◽

Substitution Mutations

ABSTRACT Salmonella enterica serovar Typhimurium (S. Typhimurium) relies upon the inner membrane protein PbgA to enhance outer membrane (OM) integrity and promote virulence in mice. The PbgA transmembrane domain (residues 1 to 190) is essential for viability, while the periplasmic domain (residues 191 to 586) is dispensable. Residues within the basic region (residues 191 to 245) bind acidic phosphates on polar phospholipids, like for cardiolipins, and are necessary for salmonella OM integrity. S. Typhimurium bacteria increase their OM cardiolipin concentrations during activation of the PhoPQ regulators. The mechanism involves PbgA’s periplasmic globular region (residues 245 to 586), but the biological role of increasing cardiolipins on the surface is not understood. Nonsynonymous polymorphisms in three essential lipopolysaccharide (LPS) synthesis regulators, lapB (also known as yciM), ftsH, and lpxC, variably suppressed the defects in OM integrity, rifampin resistance, survival in macrophages, and systemic colonization of mice in the pbgAΔ191–586 mutant (in which the PbgA periplasmic domain from residues 191 to 586 is deleted). Compared to the OMs of the wild-type salmonellae, the OMs of the pbgA mutants had increased levels of lipid A-core molecules, cardiolipins, and phosphatidylethanolamines and decreased levels of specific phospholipids with cyclopropanated fatty acids. Complementation and substitution mutations in LapB and LpxC generally restored the phospholipid and LPS assembly defects for the pbgA mutants. During bacteremia, mice infected with the pbgA mutants survived and cleared the bacteria, while animals infected with wild-type salmonellae succumbed within 1 week. Remarkably, wild-type mice survived asymptomatically with pbgA-lpxC salmonellae in their livers and spleens for months, but Toll-like receptor 4-deficient animals succumbed to these infections within roughly 1 week. In summary, S. Typhimurium uses PbgA to influence LPS assembly during stress in order to survive, adapt, and proliferate within the host environment.

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Correlation of Phenotype with the Genotype of Egg-Contaminating Salmonella enterica Serovar Enteritidis

Applied and Environmental Microbiology ◽

10.1128/aem.71.8.4388-4399.2005 ◽

2005 ◽

Vol 71 (8) ◽

pp. 4388-4399 ◽

Cited By ~ 42

Author(s):

Cesar A. Morales ◽

Steffen Porwollik ◽

Jonathan G. Frye ◽

Hailu Kinde ◽

Michael McClelland ◽

...

Keyword(s):

Microarray Analysis ◽

Dna Sequences ◽

Salmonella Enterica ◽

Respiratory Activity ◽

Phage Type ◽

Field Isolate ◽

Phenotype Microarray ◽

Wild Type ◽

Genomic Changes ◽

Phage Types

ABSTRACT The genotype of Salmonella enterica serovar Enteritidis was correlated with the phenotype using DNA-DNA microarray hybridization, ribotyping, and Phenotype MicroArray analysis to compare three strains that differed in colony morphology and phage type. No DNA hybridization differences were found between two phage type 13A (PT13A) strains that varied in biofilm formation; however, the ribotype patterns were different. Both PT13A strains had DNA sequences similar to that of bacteriophage Fels2, whereas the PT4 genome to which they were compared, as well as a PT4 field isolate, had a DNA sequence with some similarity to the bacteriophage ST64b sequence. Phenotype MicroArray analysis indicated that the two PT13A strains and the PT4 field isolate had similar respiratory activity profiles at 37°C. However, the wild-type S. enterica serovar Enteritidis PT13A strain grew significantly better in 20% more of the 1,920 conditions tested when it was assayed at 25°C than the biofilm-forming PT13A strain grew. Statistical analysis of the respiratory activity suggested that S. enterica serovar Enteritidis PT4 had a temperature-influenced dimorphic metabolism which at 25°C somewhat resembled the profile of the biofilm-forming PT13A strain and that at 37°C the metabolism was nearly identical to that of the wild-type PT13A strain. Although it is possible that lysogenic bacteriophage alter the balance of phage types on a farm either by lytic competition or by altering the metabolic processes of the host cell in subtle ways, the different physiologies of the S. enterica serovar Enteritidis strains correlated most closely with minor, rather than major, genomic changes. These results strongly suggest that the pandemic of egg-associated human salmonellosis that came into prominence in the 1980s is primarily an example of bacterial adaptive radiation that affects the safety of the food supply.

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Salmonella enterica subspecies enterica serovar Enteritidis Salmonella pathogenicity island 2 type III secretion system: role in intestinal colonization of chickens and systemic spread

Microbiology ◽

10.1099/mic.0.038018-0 ◽

2010 ◽

Vol 156 (9) ◽

pp. 2770-2781 ◽

Cited By ~ 18

Author(s):

Amanda L. S. Wisner ◽

Taseen S. Desin ◽

Birgit Koch ◽

Po-King S. Lam ◽

Emil M. Berberov ◽

...

Keyword(s):

Type Iii Secretion ◽

Salmonella Enterica ◽

Type Strain ◽

Wild Type Strain ◽

Type Iii Secretion System ◽

Secretion System ◽

Host Cells ◽

Wild Type ◽

Type Iii ◽

Systemic Spread

Salmonella enterica subspecies enterica serovar Enteritidis (S. Enteritidis) has been identified as a significant cause of salmonellosis in humans. Salmonella pathogenicity islands 1 and 2 (SPI-1 and SPI-2) each encode a specialized type III secretion system (T3SS) that enables Salmonella to manipulate host cells at various stages of the invasion/infection process. For the purposes of our studies we used a chicken isolate of S. Enteritidis (Sal18). In one study, we orally co-challenged 35-day-old specific pathogen-free (SPF) chickens with two bacterial strains per group. The control group received two versions of the wild-type strain Sal18: Sal18 attTn7 : : tet and Sal18 attTn7 : : cat, while the other two groups received the wild-type strain (Sal18 attTn7 : : tet) and one of two mutant strains. From this study, we concluded that S. Enteritidis strains deficient in the SPI-1 and SPI-2 systems were outcompeted by the wild-type strain. In a second study, groups of SPF chickens were challenged at 1 week of age with four different strains: the wild-type strain, and three other strains lacking either one or both of the SPI-1 and SPI-2 regions. On days 1 and 2 post-challenge, we observed a reduced systemic spread of the SPI-2 mutants, but by day 3, the systemic distribution levels of the mutants matched that of the wild-type strain. Based on these two studies, we conclude that the S. Enteritidis SPI-2 T3SS facilitates invasion and systemic spread in chickens, although alternative mechanisms for these processes appear to exist.

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