scholarly journals Spontaneous Excision of the Salmonella enterica Serovar Enteritidis-Specific Defective Prophage-Like Element φSE14

2010 ◽  
Vol 192 (8) ◽  
pp. 2246-2254 ◽  
Author(s):  
Carlos A. Santiviago ◽  
Carlos J. Blondel ◽  
Carolina P. Quezada ◽  
Cecilia A. Silva ◽  
Pia M. Tobar ◽  
...  
Keyword(s):  
Salmonella Enterica ◽  
Growth Conditions ◽  
Open Reading Frames ◽  
Salmonella Enterica Serovar Enteritidis ◽  
Major Health Problem ◽  
Major Health ◽  
Detection Systems ◽  
Defective Prophage ◽  
Related Proteins ◽  
Reference Strains

ABSTRACT Salmonella enterica serovar Enteritidis has emerged as a major health problem worldwide in the last few decades. DNA loci unique to S. Enteritidis can provide markers for detection of this pathogen and may reveal pathogenic mechanisms restricted to this serovar. An in silico comparison of 16 Salmonella genomic sequences revealed the presence of an ∼12.5-kb genomic island (GEI) specific to the sequenced S. Enteritidis strain NCTC13349. The GEI is inserted at the 5′ end of gene ydaO (SEN1377), is flanked by 308-bp imperfect direct repeats (attL and attR), and includes 21 open reading frames (SEN1378 to SEN1398), encoding primarily phage-related proteins. Accordingly, this GEI has been annotated as the defective prophage SE14 in the genome of strain NCTC13349. The genetic structure and location of φSE14 are conserved in 99 of 103 wild-type strains of S. Enteritidis studied here, including reference strains NCTC13349 and LK5. Notably, an extrachromosomal circular form of φSE14 was detected in every strain carrying this island. The presence of attP sites in the circular forms detected in NCTC13349 and LK5 was confirmed. In addition, we observed spontaneous loss of a tetRA-tagged version of φSE14, leaving an empty attB site in the genome of strain NCTC13349. Collectively, these results demonstrate that φSE14 is an unstable genetic element that undergoes spontaneous excision under standard growth conditions. An internal fragment of φSE14 designated Sdf I has been used as a serovar-specific genetic marker in PCR-based detection systems and as a tool to determine S. Enteritidis levels in experimental infections. The instability of this region may require a reassessment of its suitability for such applications.

scholarly journals Evaluation of the Immunogenicity and Biological Activity of theCitrobacter freundiiVi-CRM197Conjugate as a Vaccine forSalmonella entericaSerovar Typhi

2011 ◽  
Vol 18 (3) ◽  
pp. 460-468 ◽  
Author(s):  
Simona Rondini ◽  
Francesca Micoli ◽  
Luisa Lanzilao ◽  
Christine Hale ◽  
Allan J. Saul ◽  
...  
Keyword(s):  
Salmonella Enterica ◽  
Capsular Polysaccharide ◽  
Protective Efficacy ◽  
Growth Conditions ◽  
Protein Ratio ◽  
Major Health Problem ◽  
Major Health ◽  
Serovar Typhimurium ◽  
Toxin Protein

ABSTRACTTyphoid fever remains a major health problem in developing countries. Young children are at high risk, and a vaccine effective for this age group is urgently needed. Purified capsular polysaccharide fromSalmonella entericaserovar Typhi (Vi) is licensed as a vaccine, providing 50 to 70% protection in individuals older than 5 years. However, this vaccine is ineffective in infants. Vi conjugated to a carrier protein (i.e., an exoprotein A mutant fromPseudomonas aeruginosa[rEPA]) is highly immunogenic, provides long-term protection, and shows more than 90% protective efficacy in children 2 to 5 years old. Here, we describe an alternative glycoconjugate vaccine forS. Typhi, Vi-CRM197, where Vi was obtained fromCitrobacter freundiiWR7011 and CRM197, the mutant diphtheria toxin protein, was used as the carrier. We investigated the optimization of growth conditions for Vi production fromC. freundiiWR7011 and the immunogenicity of Vi-CRM197conjugates in mice. The optimal saccharide/protein ratio of the glycoconjugates was identified for the best antibody production. We also demonstrated the ability of this new vaccine to protect mice against challenge with Vi-positiveSalmonella entericaserovar Typhimurium.

scholarly journals Actinobacillus pleuropneumoniae Iron Transport: a Set of exbBD Genes Is Transcriptionally Linked to the tbpB Gene and Required for Utilization of Transferrin-Bound Iron

2000 ◽  
Vol 68 (3) ◽  
pp. 1164-1170 ◽  
Author(s):  
Walaiporn Tonpitak ◽  
Svenja Thiede ◽  
Winfried Oswald ◽  
Nina Baltes ◽  
Gerald-F. Gerlach
Keyword(s):  
Actinobacillus Pleuropneumoniae ◽  
Growth Conditions ◽  
Open Reading Frames ◽  
Pcr Analysis ◽  
Iron Restriction ◽  
Polycistronic Mrna ◽  
Transferrin Binding Proteins ◽  
Reference Strains ◽  
Reading Frames ◽  
Additional Iron

ABSTRACT Upon iron restriction, Actinobacillus pleuropneumoniaehas been shown to express the transferrin-binding proteins TbpB and TbpA, both of which have been implied to be important virulence factors. In order to identify additional iron-regulated proteins, we cloned and analyzed the region upstream of the transferrin-binding protein genes in an A. pleuropneumoniae serotype 7 strain. We located immediately upstream of the tbpB gene two open reading frames which were 43% homologous to the neisserial ExbBD protein genes. By raising specific antibodies, we showed that ExbB is expressed under iron-limiting growth conditions only, and RT-PCR analysis revealed that the exbBD genes and thetbpB gene are transcribed on a single polycistronic mRNA. By constructing an isogenic and nonpolar exbBD mutant, we showed that the exbBD genes are required by A. pleuropneumoniae for utilization of transferrin-bound iron. Using PCR and Western blotting, we showed that the genetic organization found in A. pleuropneumoniae serotype 7 is similar in all 12A. pleuropneumoniae serotype reference strains.

scholarly journals Low-Molecular-Weight Plasmid of Salmonella enterica Serovar Enteritidis Codes for Retron Reverse Transcriptase and Influences Phage Resistance

2001 ◽  
Vol 183 (9) ◽  
pp. 2852-2858 ◽  
Author(s):  
I. Rychlik ◽  
A. Sebkova ◽  
D. Gregorova ◽  
R. Karpiskova
Keyword(s):  
Molecular Weight ◽  
Reverse Transcriptase ◽  
Salmonella Enterica ◽  
Open Reading Frames ◽  
Cold Shock Protein ◽  
Phage Resistance ◽  
Low Molecular Weight ◽  
Salmonella Enterica Serovar Enteritidis ◽  
Reverse Transcriptases ◽  
Double Stranded Dna

ABSTRACT Retron reverse transcriptases are unusual procaryotic enzymes capable of synthesis of low-molecular-weight DNA by reverse transcription. All of the so-far-described DNA species synthesized by retron reverse transcriptases have been identified as multicopy single-stranded DNA. We have shown that Salmonella entericaserovar Enteritidis is also capable of synthesis of the low-molecular-weight DNA by retron reverse transcriptase. Surprisingly,Salmonella serovar Enteritidis-produced low-molecular-weight DNA was shown to be a double-stranded DNA with single-stranded overhangs (sdsDNA). The sdsDNA was 72 nucleotides (nt) long, of which a 38-nt sequence was formed by double-stranded DNA with 19- and 15-nt single-stranded overhangs, respectively. Three open reading frames (ORFs), encoded by the 4,053-bp plasmid, were essential for the production of sdsDNA. These included an ORF with an unknown function, the retron reverse transcriptase, and an ORF encoding the cold shock protein homologue. This plasmid was also able to confer phage resistance onto the host cell by a mechanism which was independent of sdsDNA synthesis.

scholarly journals Competitive Exclusion of Salmonella enterica serovar Enteritidis by Lactobacillus crispatus and Clostridium lactatifermentans in a Sequencing Fed-Batch Culture

2002 ◽  
Vol 68 (2) ◽  
pp. 555-559 ◽  
Author(s):  
Paul W. J. J. van der Wielen ◽  
Len J. A. Lipman ◽  
Frans van Knapen ◽  
Steef Biesterveld
Keyword(s):  
Mixed Culture ◽  
Salmonella Enterica ◽  
Broiler Chickens ◽  
Competitive Exclusion ◽  
Batch Reactor ◽  
Growth Conditions ◽  
Fed Batch ◽  
Salmonella Enterica Serovar Enteritidis ◽  
Lactobacillus Crispatus ◽  
Fed Batch Culture

ABSTRACT Competitive exclusion of Salmonella enterica serovar Enteritidis by a mixed culture of Lactobacillus crispatus and Clostridium lactatifermentans was studied in a sequencing fed-batch reactor mimicking the cecal ecophysiology of broiler chickens. Growth of serovar Enteritidis was inhibited by a mixed culture of L. crispatus and C. lactatifermentans at pH 5.8 but not by a monoculture of L. crispatus at the same pH. Moreover, experiments performed at pH 7.0 did not show growth inhibition of serovar Enteritidis. L. crispatus fermented lactose to lactate, and C. lactatifermentans fermented the lactate to acetate and propionate in a mixed culture of L. crispatus and C. lactatifermentans growing on lactose. In contrast, only lactate was produced from lactose by a monoculture of L. crispatus. At pH 5.8 considerable concentrations of acetate and propionate were present as undissociated acids, whereas only trace levels of undissociated lactate were present at pH 5.8 due to the low pKa of lactate. At pH 7.0 all three acids were present in their dissociated forms. We conclude that a mixed culture of L. crispatus and C. lactatifermentans inhibits growth of serovar Enteritidis under cecal growth conditions. The undissociated forms of acetate and propionate produced in the mixed culture inhibited the growth of serovar Enteritidis.

scholarly journals Sugar sulfates are not hydrolyzed by the acid-inducible sulfatase AslA from Salmonella enterica Enteritidis NalR and Kentucky 3795 at pH 5.5

2017 ◽  
Vol 63 (8) ◽  
pp. 739-744
Author(s):  
Arpeeta Ganguly ◽  
Rolf D. Joerger
Keyword(s):  
Salmonella Enterica ◽  
Salmonella Enterica Serovar Typhimurium ◽  
Open Reading Frames ◽  
Salmonella Enterica Serovar Enteritidis ◽  
Heparin Sulfate ◽  
Serovar Typhimurium ◽  
Type Strains ◽  
Reading Frames ◽  
Adhesion And Invasion ◽  
Invasion Assays

The open reading frames SEN0085 and SeKA_A4361, from Salmonella enterica serovar Enteritidis NalR and serovar Kentucky 3795, respectively, corresponding to the acid-inducible sulfatase gene aslA from Salmonella enterica serovar Typhimurium, were previously suggested by microarray analysis to be differentially expressed under acid conditions. However, growth and enzyme activity tests in the present study demonstrated that both wild-type strains exhibited sulfatase activity with 4-nitrophenyl sulfate and 5-bromo-4-chloro-3 indolyl sulfate at pH 5.5. The acid sulfatase does not appear to be involved in sugar sulfate, tyrosine sulfate, 4-hydroxy-3-methoxyphenylglycol sulfate, heparin sulfate, or chondroitin sulfate hydrolysis at pH 5.5. Adhesion and invasion assays did not reveal differences between the serotypes and their corresponding aslA deletion mutants. Thus, the role and substrate(s) of AslA, a protein unique to salmonella and encoded in all sequenced Salmonella strains, remain elusive.

Detection of Mycobacterium tuberculosis in smear negative sputum by PCR

2012 ◽  
Vol 6 (2) ◽  
pp. 2-6 ◽  
Author(s):  
Mohammad Jobayer ◽  
SM Shamsuzzaman ◽  
Kazi Zulfiquer Mamun
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Pulmonary Tuberculosis ◽  
Accurate Method ◽  
Major Health Problem ◽  
Major Health ◽  
Tuberculosis Patients ◽  
Diagnostic Potential ◽  
Total Death ◽  
Smear Negative ◽  
Negative Sputum

Pulmonary tuberculosis is a major health problem in Bangladesh that is responsible for about 7% of total death in a year. This study was conducted to isolate and identify Mycobacterium tuberculosis from sputum and to evaluate the efficacy of PCR as a modern diagnostic tool, for diagnosis of pulmonary tuberculosis, especially in the smear negative cases. One hundred and fifty suspected pulmonary TB patients (male/ female: 97/53) were included in this study. Single morning sputum was collected from each patient and diagnostic potential of PCR was compared with staining and culture. Twenty five (16.7%) sputum were positive by ZN stained smear. Among 125 smear negative samples, 13 (10.4%) yielded growth in culture in LJ media and 21 (16.8%) samples were positive by PCR. The sensitivity and specificity of PCR in smear negative cases was 100% and 92.9% respectively. Mean detection time in PCR was 24 hours. PCR detected M. tuberculosis in 21 smear negative and 9 culture negative samples. For diagnosis of tuberculosis in smear negative cases, PCR directly from sputum was a very sensitive and accurate method. In conclusion, PCR may be done, especially in clinically suspected pulmonary tuberculosis patients who remain negative by conventional methods.DOI: http://dx.doi.org/10.3329/bjmm.v6i2.19368 Bangladesh J Med Microbiol 2012; 06(02): 2-6

Evaluation of Whole Genome Sequencing for outbreak detection of Salmonella enterica serovar Enteritidis

2020 ◽  
Author(s):  
Ainhoa Arrieta-Gisasola ◽  
Aitor Atxaerandio Landa ◽  
Javier Garaizar ◽  
Joseba Bikandi ◽  
José Karkamo ◽  
...  
Keyword(s):  
Whole Genome Sequencing ◽  
Genome Sequencing ◽  
Salmonella Enterica ◽  
Outbreak Detection ◽  
Whole Genome ◽  
Salmonella Enterica Serovar Enteritidis

Prevention and Treatment of Early Childhood Caries (ECC)

2016 ◽  
Vol 1 (3) ◽  
Author(s):  
Jeffrey .
Keyword(s):  
Early Childhood ◽  
Health Problem ◽  
Early Childhood Caries ◽  
Health Providers ◽  
Missing Teeth ◽  
Optimal Basis ◽  
Major Health Problem ◽  
Major Health ◽  
Childhood Caries

Early Childhood Caries (ECC) is a chronic disease that can be prevented. It commonlyaffects children involving in one or more decayed (with lesions or not) teeth, missing teeth (dueto caries), or teeth with fillings in children aged under 71 months. The disease is sometimesoverlooked, but this condition usually affects the general health of children. Early detection ofEarly Childhood Caries (ECC) can prevent problems which are harmful to children. Therefore,the ECC must be prevented and for teeth that have had dental caries they should be givenproper treatment so as not to worsen and affect the quality of life in children. Prevention of thisdisease is a significant component in any health program to prepare for the optimal basis forthe oral health of children. This condition will become a serious health problem if not handledproperly, and it is a major health problem for health providers throughout the world.Primarypreventive must be initiated since a woman getting pregnant.Keywords: Early Childhood Caries (ECC), prevention, treatment

Salivary and Serum Biochemical Alterations in Patients with Acute Viral Hepatitis

2018 ◽  
Vol 69 (3) ◽  
pp. 747-751 ◽  
Author(s):  
Daniela Gabriela Badita ◽  
Iulia Ioana Stanescu ◽  
Andra Balcangiu Stroescu ◽  
Dan Piperea Sianu ◽  
Daniela Miricescu ◽  
...  
Keyword(s):  
Viral Hepatitis ◽  
Hepatitis A ◽  
Hepatitis A Virus ◽  
World Population ◽  
Major Health Problem ◽  
Major Health ◽  
Biochemical Alterations ◽  
B Virus ◽  
Serum Biochemical ◽  
Viral Hepatitis A

Viral hepatitis represents a major health problem worldwide. Approximately 1.4 million people are infected with hepatitis A virus every year, although given that most of the cases evolve asymptomatically the real number could be even higher. At the same time, hepatitis B virus affects up to 30% of the world population and represents one of the main causes of cirrhosis and hepatocellular carcinoma. Thus, it is very important to understand the physiopathology of viral hepatitis A and B not only for the diagnosis, but also for the therapeutic protocol. The present research aimed to determine if HAV and HBV can alter serum and salivary levels of total protein and of 2 important electrolytes: calcium and potassium.

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