Salmonella enterica serovar Enteritidis biofilm lifestyle induces lower pathogenicity and reduces inflammatory response in a murine model compared to planktonic bacteria.

Salmonellaenterica serovar Enteritidis (S. Enteritidis) is the most frequent serovar involved in human salmonellosis. It has been demonstrated that about 80% of infections are related to biofilm formation.

Growth conditions affect biofilms of producing mastitis: Contribution of MALDI-TOF-MS to strain characterization.

Bovine mastitis is a disease of dairy cattle prevalent throughout the world that causes alterations in the quality and composition of milk, compromising technological performance. is one of the most important pathogens that produce clinical, subclinical, and chronic mastitis. Biofilms are considered a virulence factor necessary for the survival of in the mammary gland.

Salmonella Enteritidis foodborne infection induces altered placental morphometrics in the murine model.

Introduction: Salmonella foodborne disease during pregnancy causes a significant fetal loss in domestic livestock and preterm birth, chorioamnionitis and miscarriage in humans. These complications could be associated with alterations in placental structure. This study was aimed to determine how a low dose of Salmonella Enteritidis during late gestation affects placental histomorphometric in mice.

Activation of iNKT Cells Prevents Salmonella-Enterocolitis and Salmonella-Induced Reactive Arthritis by Downregulating IL-17-Producing γδT Cells.

Reactive arthritis (ReA) is an inflammatory condition of the joints that arises following an infection. enterocolitis is one of the most common infections leading to ReA. Although the pathogenesis remains unclear, it is known that IL-17 plays a pivotal role in the development of ReA.

Dam methylation is required for efficient biofilm production in Salmonella enterica serovar Enteritidis.

The ecological success of Salmonella enterica to survive in different environments is due, in part, to the ability to form biofilms, something which is especially important for food industry. The aim of the current study was to evaluate the involvement of Dam methylation in biofilm production in S. Enteritidis strains.

Salmonella enterica serovar Enteritidis enterocolitis during late stages of gestation induces an adverse pregnancy outcome in the murine model.

Foodborne diseases caused by Salmonella enterica serovar Enteritidis (S. Enteritidis) are a significant health problem. Pregnancy, state of immunological tolerance, is a predisposing condition for the development of infections with intracellular pathogens.

Dam methylation regulates the expression of SPI-5-encoded sopB gene in Salmonella enterica serovar Typhimurium.

DNA adenine methylation is an essential factor in Salmonella virulence. Here, we investigate the involvement of DNA adenine methylase (Dam) in the expression and translocation of a SPI-5-encoded effector of S. Typhimurium.

AvrA effector protein of Salmonella enterica serovar Enteritidis is expressed and translocated in mesenteric lymph nodes at late stages of infection in mice.

Salmonellosis is a major health problem worldwide. Salmonella enterica serovar Enteritidis (S. Enteritidis) has been a primary cause of Salmonella outbreaks in many countries.

Consumption of Lactobacillus casei fermented milk prevents Salmonella reactive arthritis by modulating IL-23/IL-17 expression.

Reactive arthritis is the development of sterile joint inflammation as a sequel to a remote infection, often in the gut. We have previously shown that a low dose of S. enteritidis inoculated to streptomycin-pretreated mice generates a self-limiting enterocolitis suitable for studying reactive arthritis.

Dam methylation participates in the regulation of PmrA/PmrB and RcsC/RcsD/RcsB two component regulatory systems in Salmonella enterica serovar Enteritidis.

The absence of Dam in Salmonella enterica serovar Enteritidis causes a defect in lipopolysaccharide (LPS) pattern associated to a reduced expression of wzz gene. Wzz is the chain length regulator of the LPS O-antigen. Here we investigated whether Dam regulates wzz gene expression through its two known regulators, PmrA and RcsB.

Salmonella enterica induces joint inflammation and expression of interleukin-17 in draining lymph nodes early after onset of enterocolitis in mice.

In developing countries, one-third of reactive arthritis (ReA) cases are associated with Salmonella enterocolitis; nevertheless, there is no animal model for studying this pathology. Here we induced a self-limiting Salmonella enterica serovar Enteritidis enterocolitis in mice to analyze the onset of ReA. BALB/c mice received orally 20 μg of streptomycin 24 h before intragastric inoculation of a low dose (3 × 10(3) to 4 × 10(3) CFU) of S.

SopB effector protein of Salmonella Typhimurium is translocated in mesenteric lymph nodes during murine salmonellosis.

Salmonella Typhimurium harbors two Salmonella pathogenicity islands (SPIs), each encoding a type three secretion system for virulence proteins. Although there is increasing evidence of postinvasion roles for SPI-1, it has been generally accepted that SPI-1 genes are downregulated following the invasion process. Here, we analyzed the expression and translocation of SopB in vitro, in cell culture and in vivo.

Dam and its role in pathogenicity of Salmonella enterica.

Dam methylation is an essential factor involved in the virulence of an increasing number of bacterial pathogens including Salmonella enterica. Lack of Dam methylation causes severe attenuation in animal models. It has been proposed that dysregulation of Dam activity is potentially a general strategy for the generation of vaccines against bacterial pathogens.

Dam methylation controls O-antigen chain length in Salmonella enterica serovar enteritidis by regulating the expression of Wzz protein.

We reported previously that a Salmonella enterica serovar Enteritidis dam mutant expressing a truncated Dam protein does not agglutinate in the presence of specific antibodies against O9 polysaccharide. Here we investigate the participation of Dam in lipopolysaccharide (LPS) synthesis in Salmonella. The LPS O-antigen profiles of a dam null mutant (SEDeltadam) and the Salmonella serovar Enteritidis parental strain were examined by using electrophoresis and silver staining.

Impaired synthesis and secretion of SopA in Salmonella Typhimurium dam mutants.

DNA adenine methylation regulates virulence gene expression in certain bacteria, including Salmonella Typhimurium. The aim of this study was to investigate the involvement of DNA adenine methylase (Dam) methylation in the expression and secretion of the SPI-1 effector protein SopA. For this purpose, SopA-FLAG-tagged wild-type and dam strains of Salmonella Typhimurium were constructed.

Sublethal infection with Salmonella Enteritidis by the natural route induces intestinal and joint inflammation in mice.

Reactive arthritis (ReA) is a sterile inflammation triggered by a distal mucosal infection, which suggests a contribution from bacterial products. Investigation on the pathogenesis of ReA is difficult because of the limited studies that can be performed in humans; therefore the availability of animal models is crucial. We hereby describe a murine model for studying the early stages of Salmonella-induced ReA.

Host response to a dam mutant of Salmonella enterica serovar enteritidis with a temperature-sensitive phenotype.

The temperature-sensitive dam mutant strain of Salmonella enterica serovar Enteritidis SD1 is highly attenuated and induces innate and protective immunity in mice. SD1 activates NF-kappaB and induces gamma interferon secretion. Early interaction of the SD1 mutant with intestinal epithelial cells was associated with ruffling of enterocytes.

Involvement of intestinal inducible nitric oxide synthase (iNOS) in the early stages of murine salmonellosis.

Local induction of inducible nitric oxide synthase (iNOS) and apoptosis was examined in the intestine of mice infected with virulent Salmonella enterica serovar Enteritidis 5694 (S. enteritidis) and its attenuated derivative mutant E/1/3. Both, intestinal iNOS mRNA expression and iNOS activity showed a peak at 4 h only in animals receiving the virulent S.