bacillus salmonella typhi: Topics by WorldWideScience.org

Salmonella enterica Serovar Typhimurium Expressing a Chromosomally Integrated Copy of the Bacillus anthracis Protective Antigen Gene Protects Mice against an Anthrax Spore Challenge

BackgroundThe diagnosis of typhoid fever is confirmed by culture of Salmonella enterica serotype Typhi (S. typhi). However, a more rapid, simpler,...Full Text Available

Global Analysis of the General Stress Response of Bacillus subtilis

Protective immunity against infection with Bacillus anthracis is almost entirely based on a response to the protective antigen (PA), the binding moiety for the two other toxin components....Full Text Available

2003-07-01

Distribution, Frequency, and Diversity of Bacillus thuringiensis in an Animal Feed Mill

Gene arrays containing all currently known open reading frames of Bacillus subtilis were used to examine the general stress response of Bacillus. By proteomics, transcriptional...Full Text Available

2001-10-01

Sources of salmonellae in an uninfected commercially-processed broiler flock.

Bacillus thuringiensis was isolated from 36 of 50 residue samples obtained from an animal feed mill (a stored-product environment). Of 710 selected colonies having Bacillus...Full Text Available

1992-04-01

Flock infection and transport as sources of salmonellae in broiler chickens and carcasses.

Cultural monitoring was used to study the incidence and sources of salmonellae in a 4160 bird broiler flock during the growing period, transport and processing in a commercial plant. No salmonellae...Full Text Available

1980-07-01

Farm-level risk factors for the presence of Salmonella in 89 Alberta swine-finishing barns

Cultural monitoring was used to determine the incidence and sources of salmonellae in a 4160-bird broiler flock raised on litter in 32 pens. Twenty-five of the pens remained apparently free of salmonellae...Full Text Available

1980-07-01

This study investigated potential risk factors for the presence of Salmonella on 89 Alberta swine-finishing farms with the use of a questionnaire. Salmonella status...Full Text Available

2007-10-01

Characterization of cry Genes in a Mexican Bacillus thuringiensis Strain Collection

In recent years, Salmonella enteritidis has become an increasingly important public health problem in Italy. In some parts of the country, the fraction of total human salmonella isolates...Full Text Available

1993-04-01

Optimization of Culture Condition for the Hydrocinnamic Acid Production from Bacillus subtilis IJ-31

Mexico is located in a transition zone between the Nearctic and Neotropical biogeographical regions and contains a rich and unique biodiversity. A total of 496 Bacillus thuringiensis...Full Text Available

1998-12-01

Biochemical characterization of Alanine racemase- a spore protein produced by Bacillus anthracis

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2005-09-01

CLINICOBACTERIOLOGICAL AND EPIDEMIOLOGICAL ...

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2009-01-01

Thioredoxin Is an Essential Protein Induced by Multiple Stresses in Bacillus subtilis

... Salmonella. Vdgella and Brucela also to the diagnosis of the septic- tylphoidal and enteric form of human peendotuber- auloals. ...

1963-11-01

Sodium ion-dependent amino acid transport in membrane vesicles of Bacillus stearothermophilus.

Thioredoxin, a small, ubiquitous protein which participates in redox reactions through the reversible oxidation of its active center dithiol to a disulfide, is an essential protein in Bacillus...Full Text Available

1998-04-01

Resistance of Bacillus subtilis var. niger Spores Occluded in Water-insoluble Crystals to Three Sterilization Agents

Amino acid transport in membrane vesicles of Bacillus stearothermophilus was studied. A relatively high concentration of sodium ions is needed for uptake of L-alanine (Kt = 1.0 mM) and L-leucine (Kt...Full Text Available

1991-01-01

Rapid in situ hybridization technique using 16S rRNA segments for detecting and differentiating the closely related gram-positive organisms Bacillus polymyxa and Bacillus macerans

The resistance to destruction of spores of Bacillus subtilis var. niger occluded in crystals of calcium carbonate and exposed to ethylene oxide and moist and dry heat...Full Text Available

1967-07-01

Purification and properties of penicillinases from two strains of Bacillus licheniformis: a chemical, physicochemical and physiological comparison

A rapid, sensitive, inexpensive in situ hybridization technique, using 30-mer 16S rRNA probes, can

1992-01-01

Preliminary X-ray crystallographic studies of Bacillus subtilis SpeA protein

1. The penicillinases formed by penicillinase-constitutive mutant strains from two closely related varieties (749 and 6346) of Bacillus licheniformis have been isolated, characterized...Full Text Available

1965-03-01

Plasmid Transfer between Bacillus thuringiensis subsp. israelensis Strains in Laboratory Culture, River Water, and Dipteran Larvae

The speA gene in Bacillus subtilis encodes arginine decarboxylase, which catalyzes the conversion of arginine to agmatine. Arginine decarboxylase is an important enzyme...Full Text Available

Nonnative Proteins Induce Expression of the Bacillus subtilis CIRCE Regulon

Plasmid transfer between strains of Bacillus thuringiensis subsp. israelensis was studied under a range of environmentally relevant laboratory conditions in vitro,...Full Text Available

2001-01-01

Mosquitocidal activity of the CryIC delta-endotoxin from Bacillus thuringiensis subsp. aizawai.

The chaperone-encoding groESL and dnaK operons constitute the CIRCE regulon of Bacillus subtilis. Both operons are under negative control of the repressor...Full Text Available

1998-06-01

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Mechanism of L-glutamate transport in membrane vesicles from Bacillus stearothermophilus.

The cloned 135-kDa CryIC delta-endotoxin from Bacillus thuringiensis is a lepidopteran-active toxin, displaying high activity in vivo against Spodoptera litoralis and Spodoptera frugiperda larvae and...Full Text Available

1996-02-01

Isolation of Bacillus thuringiensis from Stored Tobacco and Lasioderma serricorne (F.)

In the presence of electrochemical energy, several branched-chain neutral and acidic amino acids were found to accumulate in membrane vesicles of Bacillus stearothermophilus. The membrane vesicles contained...Full Text Available

1989-02-01

Iodination of glyceraldehyde 3-phosphate dehydrogenase from Bacillus stearothermophilus.

Bacillus thuringiensis was isolated from dried tobacco residues and dead tobacco beetles (Lasioderma serricorne (F.); Coleoptera: Anobiidae) collected in a large number...Full Text Available

1994-01-01

Inhibition of beta-lactamase of Bacillus licheniformis 749/C by compound PS-5, a new beta-lactam antibiotic.

The reaction of iodine with glyceraldehyde 3-phosphate dehydrogenase from Bacillus stearothermophilus was investigated. The active-site thiol group of the cysteine residue homologous with cysteine-149...Full Text Available

1976-06-01

Induction and transmission of Bacillus thuringiensis tolerance in the flour moth Ephestia kuehniella

By use of a new computer-assisted u.v.-spectrophotometric assay method, the kinetic parameters of the reaction catalysed by Bacillus licheniformis 749/C beta-lactamase were re-examined and the mode...Full Text Available

1980-01-01

Identification of plasmid and Bacillus subtilis chromosomal recombination sites used for pE194 integration.

The use of Bacillus thuringiensis (Bt) endotoxins to control insect vectors of human diseases and agricultural pests is threatened by the possible evolution of resistance in major pest...Full Text Available

2004-03-02

Identification and characterization of Aedes aegypti aminopeptidase N as a putative receptor of Bacillus thuringiensis Cry11A toxin

The plasmid pE194 (3.7 kilobases) is capable of integrating into the genome of the bacterial host Bacillus subtilis in the absence of the major homology-dependent RecE recombination system. Multiple...Full Text Available

1989-05-01

Heavy metals alter the electrokinetic properties of bacteria, yeasts, and clay minerals.

Bacillus thuringiensis subsp. israelensis, which is used worldwide to control Aedes aegypti larvae, produces Cry11Aa and other toxins during...Full Text Available

2009-10-01

Expression of the ?^B-Dependent General Stress Regulon Confers Multiple Stress Resistance in Bacillus subtilis

The electrokinetic patterns of four bacterial species (Bacillus subtilis, Bacillus megaterium, Pseudomonas aeruginosa, and Agrobacterium radiobacter), two yeasts (Saccharomyces cerevisiae and Candida...Full Text Available

1992-05-01

Dynamic SpoIIIE assembly mediates septal membrane fission during Bacillus subtilis sporulation

The alternative sigma factor ς^B of Bacillus subtilis is required for the induction of approximately 100 genes after the imposition of a whole range of stresses and...Full Text Available

1999-07-01

Comparison of Disulfide Contents and Solubility at Alkaline pH of Insecticidal and Noninsecticidal Bacillus thuringiensis Protein Crystals

SpoIIIE is an FtsK-related protein that transports the forespore chromosome across the Bacillus subtilis sporulation septum. We use membrane photobleaching and protoplast assays to...Full Text Available

2010-06-01

Binary Bacterial Toxins: Biochemistry, Biology, and Applications of Common Clostridium and Bacillus Proteins

We compared two insecticidal and eight noninsecticidal soil isolates of Bacillus thuringiensis with regard to the solubility of their proteinaceous crystals at alkaline pH values. The...Full Text Available

1994-10-01

A Bacillus thuringiensis isolation method utilizing a novel stain, low selection and high throughput produced atypical results

Certain pathogenic species of Bacillus and Clostridium have developed unique methods for intoxicating cells that employ the classic enzymatic “A-B” paradigm for protein toxins. The binary...Full Text Available

2004-09-01

Transmission of Salmonella mbandaka to cattle from contaminated feed.

BackgroundBacillus thuringiensis is a bacterium known for producing protein crystals with insecticidal properties. These toxins are widely sought after for controlling...Full Text Available

The sensitivity of real-time PCR amplification targeting invasive Salmonella serovars in biological specimens

Salmonella mbandaka was isolated from cattle on three dairy farms. The duration of infection was less than four weeks and none of the animals became clinically ill. The animals had all consumed a diet...Full Text Available

1982-04-01

The relationships of salmonellae from infected broiler flocks, transport crates or processing plants to contamination of eviscerated carcases.

BackgroundPCR amplification for the detection of pathogens in biological material is generally considered a rapid and informative diagnostic technique. Invasive Salmonella...Full Text Available

The associations between milk production, milk composition and Salmonella in the bulk milk supplies of dairy farms in Ontario.

Three flocks raised for broiler or roaster performance tests were studied to determine the incidence and sources of salmonellae during the growing period, transport and processing and to relate these...Full Text Available

1982-07-01

Spread of a Salmonella typhimurium Clone Resistant to Expanded-Spectrum Cephalosporins in Three European Countries

The purpose of this study was to assess changes in dairy herd milk production and milk composition associated with changes in Salmonella contamination of bulk milk on dairy farms in southwestern Ontario....Full Text Available

1989-04-01

Salmonellosis in Botswana

Twelve Salmonella typhimurium strains resistant to broad-spectrum cephalosporins were isolated from cases of gastroenteritis during 1996 to 1998 in Russia, Hungary, and Greece. Resistance...Full Text Available

1999-11-01

Salmonella enterica in Commercial Swine Feed and Subsequent Isolation of Phenotypically and Genotypically Related Strains from Fecal Samples?

Clinical salmonellosis in cattle is infrequently recorded in Botswana, the majority of salmonella isolations being made from apparently healthy animals. A salmonella carrier rate of 6·7% was...Full Text Available

1971-09-01

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Roles of curli, cellulose and BapA in Salmonella biofilm morphology studied by atomic force microscopy

The purpose of this study was to determine the occurrence and genotypic relatedness of Salmonella enterica isolates recovered from feed and fecal samples in commercial swine production...Full Text Available

2010-11-01

Resuscitation of Salmonella enterica Serovar Typhimurium and Enterohemorrhagic Escherichia coli from the Viable but Nonculturable State by Heat-Stable Enterobacterial Autoinducer

BackgroundCurli, cellulose and the cell surface protein BapA are matrix components in Salmonella biofilms. In this study we have investigated the roles of these...Full Text Available

Phosphorylated PmrA Interacts with the Promoter Region of ugd in Salmonella enterica Serovar Typhimurium

Salmonella enterica serovar Typhimurium and enterohemorrhagic Escherichia coli were stressed by prolonged incubation in water microcosms until it was no longer possible...Full Text Available

2002-10-01

Molecular Analyses of Salmonellaenterica Isolates from Fish Feed Factories and Fish Feed Ingredients

The Salmonella PmrA-PmrB system controls the expression of genes necessary for polymyxin B resistance. Four loci were previously identified as part of the regulon, and interaction of...Full Text Available

2000-07-01

High Prevalence of Extended-Spectrum Beta Lactamases among Salmonella enterica Typhimurium Isolates from Pediatric Patients with Diarrhea in China

Isolates of the most commonly observed salmonella serovars in Norwegian fish feed factories from 1998 to 2000 (Salmonella enterica serovar Agona, S. enterica...Full Text Available

2003-02-01

Compounds Which Serve as the Sole Source of Carbon or Nitrogen for Salmonella typhimurium LT-2

We investigated the extended-spectrum beta lactamases among 62 Salmonella enterica Typhimurium isolates recovered from children with diarrhea in a Chinese pediatric hospital. A large...Full Text Available

Comparison of Genotypes of Salmonella enterica Serovar Enteritidis Phage Type 30 and 9c Strains Isolated during Three Outbreaks Associated with Raw Almonds?

About 600 compounds were screened as possible carbon or nitrogen sources for Salmonella typhimurium LT-2. About 100 utilizable compounds were found.

1969-10-01

Attenuated Salmonella typhimurium reduces ovalbumin-induced airway inflammation and T-helper type 2 responses in mice

In 2000 to 2001, 2003 to 2004, and 2005 to 2006, three outbreaks of Salmonella enterica serovar Enteritidis were linked with the consumption of raw almonds. The S....Full Text Available

2010-06-01

A Murine Model to Study the Antibacterial Effect of Copper on Infectivity of Salmonella Enterica Serovar Typhimurium

Cytokines produced by Th2 cells are responsible for the pathogenesis of asthma. Th1-biased immune responses caused by attenuated salmonella have the potential to relieve asthmatic symptoms. We evaluated...Full Text Available

2006-07-01

Invasiveness and persistence of Salmonella enteritidis, Salmonella typhimurium, and a genetically defined S. enteritidis aroA strain in young chickens.

This study investigated the effect of copper as an antibacterial agent on the infectivity of Salmonella enterica serovar Typhimurium. Mice were infected orally with a standardized dose...Full Text Available

2011-01-01

Substitution of Glycine 275 by Glutamate (G275E) in Lipase of Bacillus stearothermophilus Affects Its Catalytic Activity and Enantio- and Chain Length Specificity

Newly hatched chicks were dosed orally with a Salmonella typhimurium wild-type strain, an S. enteritidis wild-type strain, and a genetically defined S. enteritidis aroA vaccine candidate, strain CVL30....Full Text Available

1994-11-01

Proteomic Analysis of Global Changes in Protein Expression During Exposure of Gamma Radiation in Bacillus sp. HKG 112 Isolated from Saline Soil

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2000-12-01

Growth Inhibition and Induction of Stress Protein, GroEL, of Bacillus cereus Exposed to Antibacterial Peptide Isolated from Bacillus subtilis SC-8

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British Library Electronic Table of Contents (United Kingdom)

This study was conducted to investigate the antibacterial effect of BSAP-254 on Bacillus cereus with the induced stress proteins. The BSAP-254 is an antimicrobial peptide isolated from soybean-fermenting bacteria, Bacillus subtilis SC-8. It had a narrow spectrum of activity against B. cereus group. The growth inhibitory effect of BSAP-254 (50??g/mL) reduced the population of B. cereus from >108 to 104 colony-forming units per milliliter within 30?min. In B. cereus exposed to BSAP-254, 14 intracellular proteins were differentially expressed as determined by 2-DE coupled with MS. Of the differentially expressed proteins identified, the stress protein GroEL, which is heat shock protein, was induced in B. cereus exposed to antibacterial peptide.

2011-01-01

Detection and Identification of Bacteria by Gas Chromatography¹

Presence of Arsenic Resistance in Salmonella enterica Serovar Kentucky and Other Serovars Isolated from Poultry

Ether extracts of cultures of 29 strains representing 6 species of Bacillus, and of individual strains of Escherichia coli, Aerobacter aerogenes, and Pseudomonas...Full Text Available

1966-07-01

Direct detection of Salmonella without pre-enrichment in milk, ice-cream and fruit juice by PCR against hilA gene

... B. P. Rosen. An arsenic metallochaperone for an arsenic detoxification pump. Proc. Natl. Acad. Sci. U. S. A 103( ... ...

British Library Electronic Table of Contents (United Kingdom)

A novel PCR based assay was devised to specifically detect contamination of any Salmonella serovar in milk, fruit juice and ice-cream without pre-enrichment. This method utilizes primers against hilA gene which is conserved in all Salmonella serovars and absent from the close relatives of Salmonella. An optimized protocol, in terms time and money, is provided for the reduction of PCR contaminants from milk, ice-cream and juice through the use of routine laboratory chemicals. The simplicity, efficiency (time taken 3-4 h) and sensitivity (to about 5-10 CFU/ml) of this technique confers a unique advantage over other previously used time consuming detection techniques. This technique does not involve pre-enrichment of the samples or extensive sample processing, which was a pre-requisite in mos...

2012-01-01

A Response Surface Model Based on Absorbance Data for the Growth Rates of Salmonella enterica Serovar Typhimurium as a Function of Temperature, NaCl, and pH

Signal transduction pathway controlling synthesis of a class of degradative enzymes in Bacillus subtilis: expression of the regulatory genes and analysis of mutations in degS and degU.

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2007-04-01

Sequence and Organization of pXO1, the Large Bacillus anthracis Plasmid Harboring the Anthrax Toxin Genes

The rates of synthesis of a class of both secreted and intracellular degradative enzymes in Bacillus subtilis are controlled by a signal transduction pathway defined by at least four regulatory genes:...Full Text Available

1990-02-01

A Two-Dimensional Protein Gel Electrophoresis Study of the Heat Stress Response of Bacillus subtilis Cells during Sporulation

The Bacillus anthracis Sterne plasmid pXO1 was sequenced by random, “shotgun” cloning. A circular sequence of 181,654 bp was generated. One hundred forty-three open...Full Text Available

1999-10-01

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Transfer of Plasmid-Mediated CTX-M-9 from Salmonella enterica Serotype Virchow to Enterobacteriaceae in Human Flora-Associated Rats Treated with Cefixime?

The heat resistance of spores of Bacillus subtilis formed at 30°C was enhanced by pretreatment at 48°C for 30 min, 60 min into sporulation, for all four strains examined....Full Text Available

2000-09-01

Chromosomal Integration of the Extended-Spectrum ?-Lactamase Gene bla_CTX-M-15 in Salmonella enterica Serotype Concord Isolates from Internationally Adopted Children?

Food animals are a potential source of CTX-M resistance genes for humans. We evaluated the transfer of the bla_CTX-M-9 gene from an animal strain of Salmonella enterica...Full Text Available

2010-01-01

Association between Handling of Pet Treats and Infection with Salmonella enterica Serotype Newport Expressing the AmpC ?-Lactamase, CMY-2

We report the emergence of Salmonella enterica isolates of serotype Concord (and its monophasic variant 6,7:l,v:-) producing the extended-spectrum β-lactamases (ESBLs) SHV-12...Full Text Available

2009-05-01

Antimicrobial resistance, virulence-associated genes, and pulsed-field gel electrophoresis profiles of Salmonella enterica subsp. enterica serovar Typhimurium isolated from piglets with diarrhea in Korea

Resistance to the extended-spectrum cephalosporins can occur in Salmonella species via the production of extended-spectrum and AmpC β-lactamases. We describe human infections...Full Text Available

2003-10-01

Biosorption of lead from aqueous solutions by Bacillus strains possessing heavy-metal resistance

Salmonella enterica subsp. enterica serovar Typhimurium was isolated from diarrheic piglets in 2 periods, 2000–2001 (n = 25) and 2005–2006...Full Text Available

2011-01-01

British Library Electronic Table of Contents (United Kingdom)

In this study, bacterial strains were investigated in order to determine their heavy metal tolerance. The bacterial strains were identified as Bacillus cereus and Bacillus pumilus. In the batch system, the effects of operating variables such as solution pH, initial metal concentration, contact time, and adsorbent dosage were investigated. Both isolates were highly resistance to copper and lead in comparison with the control strain examined. The adsorption capacities of B. cereus and B. pumilus were found to be 22.1mg/g and 28.06mg/g, respectively. The biosorption follows pseudo-second order kinetics and the isotherm fits well to the Langmuir isotherm model. In column experiments, the biosorption was fitted well by the Thomas model. The breakthrough and exhaustion capacity of each biosorben...

2011-01-01

Phosphorylation of the Mycobacterium tuberculosis ?-Ketoacyl-Acyl Carrier Protein Reductase MabA Regulates Mycolic Acid Biosynthesis*

Pathway to Licensure for Protective Antigen-based Anthrax Vaccines ...

Mycolic acids are key cell wall components for the survival, pathogenicity, and antibiotic resistance of the human tubercle bacillus. Although it was thought that Mycobacterium tuberculosis...Full Text Available

2010-04-23

Mycobacterium tuberculosis Chaperonin 10 Is Secreted in the Macrophage Phagosome: Is Secretion Due to Dissociation and Adoption of a Partially Helical Structure at the Membrane?

... Weiss, S., D. Kobiler, H. Levy, H. Marcus, A. Pass, N. Rothschild, and Z ... of Bacillus anthracis spores conferred by a protective antigen-based vaccine in rabbits ...

Incidence and Diversity of Potentially Highly Heat-Resistant Spores Isolated at Dairy Farms

To confirm that Mycobacterium tuberculosis chaperonin 10 (Cpn10) is secreted outside the live bacillus, infected macrophages were examined by electron microscopy. This revealed that...Full Text Available

2003-07-01

Display of Recombinant Proteins on Bacillus subtilis Spores, Using a Coat-Associated Enzyme as the Carrier?

The presence of highly heat-resistant spores of Bacillus sporothermodurans in ultrahigh-temperature or sterilized consumer milk has emerged as an important item in the dairy industry....Full Text Available

2005-03-01

Biological Response Modifier Activity of an Exopolysaccharide from Paenibacillus jamilae CP-7

The display of proteins such as feed enzymes at the surface of bacterial spore systems has a great potential use for animal feed. Feed enzymes increase the digestibility of nutrients, leading to greater...Full Text Available

2010-09-01

A Response Regulator That Represses Transcription of Several Virulence Operons in the Group A Streptococcus

An extracellular polysaccharide was purified from culture supernatants of Paenibacillus jamilae CP-7, a gram-positive bacillus that was isolated from compost prepared with olive mill...Full Text Available

2001-07-01

Past, present, and future of mutagens in cooked foods.

A search for homologs of the Bacillus subtilis PhoP response regulator in the group A streptococcus (GAS) genome revealed three good candidates. Inactivation of one of these, recently...Full Text Available

1999-06-01

Mutagenic and cytotoxic activity of doxorubicin and daunorubicin derivatives on prokaryotic and eukaryotic cells.

Mutation assay with Salmonella typhimurium enabled us to detect various types of mutagens in cooked foods. A series of mutagenic heterocyclic amines has been isolated and identified in broiled fish...Full Text Available

1986-08-01

Changes in Tetracycline Susceptibility of Enteric Bacteria following Switching to Nonmedicated Milk Replacer for Dairy Calves?

The mutagenic and cytotoxic activity of two newly synthesized doxorubicin derivatives and of one daunorubicin derivative were studied in V79 Chinese hamster cells and bacteria (Salmonella typhimurium...Full Text Available

1984-07-01

Allosteric regulation of glycerol kinase by enzyme IIIglc of the phosphotransferase system in Escherichia coli and Salmonella typhimurium.

A randomized intervention study was conducted to determine if discontinuing use of calf milk replacer medicated with oxytetracycline results in increased tetracycline susceptibility in Salmonella...Full Text Available

2008-06-01

Adrenaline modulates the global transcriptional profile of Salmonella revealing a role in the antimicrobial peptide and oxidative stress resistance responses

The mechanism by which enzyme IIIglc of the bacterial phosphotransferase system regulates the activity of crystalline glycerol kinase from Escherichia coli has been studied, and the inhibitory effects...Full Text Available

1985-05-01

beta-Lactamases among extended-spectrum beta-lactamase (ESBL)-resistant Salmonella from poultry, poultry products and human patients in The Netherlands

BackgroundThe successful interaction of bacterial pathogens with host tissues requires the sensing of specific chemical and physical cues. The human gut contains a huge number of...Full Text Available

DEFF Research Database (Denmark)

Objectives: The purpose of this work was to study the genetic determinants responsible for extended-spectrum beta-lactamase (ESBL) resistance of Salmonella isolated from Dutch poultry, poultry meat and hospitalized humans. Methods: Thirty-four ESBL-resistant Salmonella isolates from The Netherlands were tested towards 21 antimicrobial agents. PCR and sequencing were used to determine the underlying genetic determinants responsible for the ESBL phenotypes. The transferability of the ESBL phenotypes was tested by conjugation to a susceptible Salmonella enterica serovar Dublin and plasmid purification, restriction fragment length polymorphism (RFLP) and pulsed-field gel electrophoresis (PFGE) were employed to further characterize a subset of the isolates. Results: A great genetic diversity was seen among the isolates. The bla(TEM-52) gene was most predominant and was found among Salmonella enterica ...

2005-01-01

Salmonella radicidation of poultry carcasses

Activity of Citrus Essential Oils against-Escherichia coli-O157:H7 and-Salmonella-spp. and Effects on Beef Subprimal Cuts under Refrigeration

This thesis reports investigations using gamma-radiation to decontaminate poultry carcasses. The application to foods of doses of ionizing radiation sufficient to reduce the number of viable specific non-sporeforming pathogenic microorganisms so that none is detectable in the treated food by any standard method is termed radicidation. The doses used in this study were at such a level that no undesirable or unfavourable side-effects occurred. The effects of these doses were studied on salmonellae and other microorganisms present in, or associated with poultry carcasses and in liquid and on solid culture media as well. Decimal reduction (D_1_0) values were estimated. These represent the dose (kGy) required to achieve a reduction in initial colony count from N_0 to 0.1 N_0. Together with the estimation of the numbers of Salmonella present per carcass the data were used to predict the effect of an ionizing radiation treatment of poultry. Data on ...

2005-09-22

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British Library Electronic Table of Contents (United Kingdom)

Abstract:- Escherichia coli-O157:H7 and-Salmonella-spp. are bacterial pathogens often associated with beef, and cause many cases of foodborne illness each year in the United States. During beef slaughter and processing, these bacteria may spread from the hide or intestines to the carcass. The objective of this research was to investigate the use of naturally occurring compounds citrus essential oils (CEOs) extracted from orange peel to reduce or eliminate these pathogens at the chilling stage of processing, or during fabrication. Brisket flats (used to simulate beef subprimals) were spot inoculated with approximately 6 log of surrogate generic-E. coli-cocktail (previously shown to be identical in growth and survival parameters to-E. coli-O157:H7 and-Salmonella-spp.). Following drying, CEOs...

2011-01-01

Unfolding analysis of the mature and unprocessed forms of Bacillus licheniformis ?-glutamyltranspeptidase

British Library Electronic Table of Contents (United Kingdom)

Bacillus licheniformis ?-glutamyltranspeptidase (BlGGT) undergoes an autocatalytic process to generate 44.9 and 21.7?kDa subunits; however, a mutant protein (T399A) loses completely the processing ability and mainly exists as a precursor. For a comprehensive understanding of their structural features, the biophysical properties of these two proteins were investigated by circular dichroism and fluorescence spectroscopy. Tryptophan fluorescence and circular dichroism spectra were nearly identical for BlGGT and T399A, but unfolding analyses revealed that these two proteins had a different sensitivity towards temperature- and guanidine hydrochloride (GdnHCl)-induced denaturation. BlGGT and the unprocessed T399A displayed T m values of 61.4?C and 68.1?C, respectively, and thermal unfolding of b...

2011-01-01

Ability of a solid state fermentation technique to significantly minimize catabolic repression of. alpha. -amylase production by Bacillus licheniformis M27

High hydrostatic pressure processing reduces Salmonella enterica serovars in diced and whole tomatoes

The production of {alpha}-amylase by Bacillus licheniformis M27 in submerged fermentation was completely inhibited due to catabolic repression in medium containing 1% glucose. In contrast, the enzyme production in a solid state fermentation system was 19,550 units/ml extract even when the medium contained 15% glucose. The peak in enzyme titre was, however, shifted from 48 to 72 h. The ability of the solid state fermentation system to significantly overcome catabolic repression was not known earlier and is probably conferred by various physico-chemical factors and culture conditions specific to the system. (orig.).

1991-08-01

British Library Electronic Table of Contents (United Kingdom)

Fresh and fresh-cut tomatoes have been associated with numerous outbreaks of salmonellosis in recent years. One effective post harvest treatment to reduce Salmonella enterica in tomatoes may be high pressure processing (HPP). The objectives of the study were to determine the potential for HPP to reduce S. enterica serovars Newport, Javiana, Braenderup and Anatum in tryptic soy broth (TSB) and to determine the effect of HPP to reduce the most pressure resistant of the four serovars from fresh diced and whole tomatoes. To evaluate pressure resistance, TSB containing 8 log CFU/ml of one of the four serovars was packaged in sterile stomacher bags and subjected to one of three different pressures (350, 450 or 550MPa) for 120s. The most pressure resistant S. enterica serovar evaluated was Braend...

2011-01-01

Biomagnetic separation of Salmonella Typhimurium with high affine and specific ligand peptides isolated by phage display technique

Tests for mutagencity of free radicals formed in irradiated sugars and amino acids

Analyses of food-borne pathogens are of great importance in order to minimize the health risk for customers. Thus, very sensitive and rapid detection methods are required. Current conventional culture techniques are very time consuming. Modern immunoassays and biochemical analysis also require pre-enrichment steps resulting in a turnaround time of at least 24 h. Biomagnetic separation (BMS) is a promising more rapid method. In this study we describe the isolation of high affine and specific peptides from a phage-peptide library, which combined with BMS allows the detection of Salmonella spp. with a similar sensitivity as that of immunomagnetic separation using antibodies.

2007-04-15

Platelet-activating factor mediates hemodynamic changes and lung injury in endotoxin-treated rats.

Radicals formed in gamma-irradiated crystals of galactose and glycine were found, upon dissolution, to cause mutagenesis of Salmonella typhimurium strains TA-98 and TA-100. Although the reproducibility of the results has not been adequately determined, they suggest the possibility of developing a test to measure the mutagenic-carcinogenic potential of radiation-induced free radicals with a microbial system.

1977-05-01

Destruction of Salmonellae on poultry meat with lysozyme, EDTA, x ray, microwave, and chlorine

Within 20 min after intraperitoneal injection of Salmonella enteritidis endotoxin in rats, blood platelet-activating factor (PAF) increased from 4.3 +/- 1.3 to 13.7 +/- 2.0 ng/ml (P less than 0.01)...Full Text Available

1987-05-01

Contribution of Gene Amplification to Evolution of Increased Antibiotic Resistance in Salmonella typhimurium

Lysozyme, ethylenediaminetetracetic acid, chlorine, x-irradiation and microwaves were used in experimental attempts to eliminate Salmonella senftenberg 775W or Salmonella typhimurium from turkey drumsticks and whole carcasses. Turkey drumsticks or whole carcasses were artificially contaminated with S. senfenberg 775W or S. typhimurium in concentrations ranging between 5 x 10"5 to 8 x 10"5 viable cells per ml. of contaminating fluid. After each treatment, samples were cultured, plated, and tested according to standard methods to determine the susceptibility of Salmonella organisms to the particular treatment. A 0.1 percent solution of lysozyme eliminated the S. senftenberg 775W at 22"0C within three hours. A 0.5 percent solution of ethylenediaminetetracetic acid failed to destroy the test organism under the same conditions. Eighty thousand rads of X-ray eliminated the test organism on turkey drumsticks but failed to remove ...

Blockade of catecholamine-induced growth by adrenergic and dopaminergic receptor antagonists in Escherichia coli O157:H7, Salmonella enterica and Yersinia enterocolitica

The use of β-lactam antibiotics has led to the evolution and global spread of a variety of resistance mechanisms, including β-lactamases, a group of enzymes that degrade the β-lactam...Full Text Available

2009-08-01

A rapid and simple DNA extraction procedure to detect Salmonella spp. and Listeria monocytogenes from fresh produce using real-time PCR

BackgroundThe ability of catecholamines to stimulate bacterial growth was first demonstrated just over a decade ago. Little is still known however, concerning the nature of the putative...Full Text Available

Effects of dietary chitosan and Bacillus subtilis on the growth performance, non-specific immunity and disease resistance of cobia, Rachycentron canadum

DNA isolation procedures significantly influence the outcome of PCR-based detection of human pathogens. Unlike clinical samples, DNA isolation from food samples such as fresh and fresh-cut produce has remained a formidable task and has hampered the sensitivity and accuracy of molecular methods. We...

British Library Electronic Table of Contents (United Kingdom)

The present study was performed to investigate the effects of various levels of dietary Bacillus subtilis and chitosan on the growth performance, non-specific immunity and protection against Vibrio harveyi infection in cobia, Rachycentron canadum. Fish were fed with the control diet and six different experimental diets containing three graded levels of B. subtilis at 2 x 10^1^0 CFU g^-^1 (0.0, 1.0, 2.0 g kg^-^1 diet) for each of two levels of chitosan (3.0 and 6.0 g kg^-^1 diet). The results of 8 weeks feeding trial showed that the survival rate ranged from 81.3% to 84.0% with no significant difference (P > 0.05). The SGR (%) in the fish fed with dietary treatments was significantly higher than that of the control fish except diet 6 group with 2.0 g kg^-^1B. subtilis and 3.0 g kg^-^1 chito...

2011-01-01

Biological control of take-all in wheat by endophytic Bacillus subtilis E1R-j and potential mode of action

British Library Electronic Table of Contents (United Kingdom)

The bacterial strain E1R-j, isolated as an endophyte from wheat roots, exhibited high antifungal activity to Gaeumannomyces graminis var. tritici (Ggt). Strain E1R-j was identified as Bacillus subtilis based on morphological, physiological and biochemical methods as well as on 16S rDNA analysis. This strain inhibited mycelium growth in vitro of numerous plant pathogenic fungi, especially of Ggt, Coniothyrium diplodiella, Phomopsis sp. and Sclerotinia sclerotiorum. In greenhouse experiments, soil drenches with cell densities of 106, 109 and 1012CFU ml-1 E1R-j reduced significantly take-all disease, caused by Ggt, in wheat seedling by 62.6%, 68.6% and 70.7%, respectively, compared to the inoculated control, 4weeks after sowing. Growth parameters such as lengths and fresh weights of roots and...

2009-01-01

Use of Organic Acids to Inactivate-Escherichia coli-O157:H7,-Salmonella-Typhimurium, and-Listeria monocytogenes-on Organic Fresh Apples and Lettuce

British Library Electronic Table of Contents (United Kingdom)

Abstract:- This study was undertaken to investigate the antimicrobial effect of organic acids against-Escherichia coli-O157:H7,-Salmonella-Typhimurium, and-Listeria monocytogenes-on whole red organic apples and lettuce. Several studies have been conducted to evaluate organic acids as sanitizers. However, no studies have compared antimicrobial effects of various organic acids on organic fresh produce, including evaluation of color changes of produce. Apples and lettuce were inoculated with a cocktail of 3 strains each of 3 foodborne pathogens provided above and treated with 1% and 2% organic acids (propionic, acetic, lactic, malic, and citric acid) for 0, 0.5, 1, 5, and 10 min. With increasing treatment time and acid concentration, organic acid treatments showed significant reduction compar...

2011-01-01

Gamma irradiation in the control of pathogenic bacteria in refrigerated ground chicken meat; Irradiacao gama no controle de bacterias patogenicas em carne de frango refrigerada

Novel approach to decontaminate food-packaging from pathogens in non-thermal and not chemical way: Chlorophyllin-based photosensitization

This work evaluated the effect of gamma radiation on reducing the population of Staphylococcus aureus, Escherichia coli nd Salmonella typhimurium in ground chicken breast stored under refrigeration. The experiment included a control and 4 doses of gamma radiation ( 2.0, 4.0, 6.0 and 8.0 kGy) along with 5 periods of storage under refrigeration ( 1, 7 14, 21 and 28 days). Samples of ground chicken breast were inoculated with Staphylococcus aureus (ATCC 14458), Escherichia coli (ATCC 11105) and Salmonella typhimurium (ATCC 0626), irradiated at temperatures between 4 and 8 deg C and stored under refrigeration (5 deg C) for 28 days. The increased radiation dose and period of storage under refrigeration caused a reduction of Staphylococcus aureus, Escherichia coli and Salmonella typhimurium populations in the ground chicken breast. Mean radiation D values determined for Staphylococcus aureus and Escherichia coli were 0.41 and ...

2000-09-01

British Library Electronic Table of Contents (United Kingdom)

This study was focused on the possibility to inactivate main food pathogens, their spores and biofilms on the surface of packaging material polyolefine by Na-chlorophyllin (Na-Chl)-based photosensitization and to compare efficiency of this treatment with conventional antimicrobials. Data indicate that Bacillus cereus and Listeria monocytogenes were effectively inactivated (7 log) by Na-Chl (7.5x10-7M)-based photosensitization in vitro and on the surface of packaging. Meanwhile to achieve adequate inactivation of thermo-resistant strains, spores or biofilms the higher Na-Chl concentration and longer illumination times had to be used. Comparison of different surface decontamination treatments reveal that photosensitization is much more effective against B. cereus and L. monocytogenes attache...

2011-01-01

Microbiological quality and biophenol content of hot air-dried Thassos cv. table olives upon storage

British Library Electronic Table of Contents (United Kingdom)

Abstract Microbiological quality and biophenol content evolution was studied in minimally processed Thassos cv table olives by hot air dehydration under mild conditions (40C, 24-h, aw-=-0.893) and storage under characteristic packaging conditions (vacuum, 100% N2 and air) at 4 and 20C over a period of 180 days. No salt was used in the production line or packaging. The undesirable microorganisms (Enterobacteriaceae, Staphylococcus aureus, Bacillus, Clostridium) were undetectable until the end of the storage period. Also, modified atmospheres prevented fungal growth at both temperatures apart from the samples stored in air, in which Penicillium and Aspergillus spp. were identified. At 20C, a coexistence of mesophilic bacteria and yeasts occurred. At 4C, yeasts were the predominant microflora...

2011-01-01

Flavonols and an oxychromonol from Piliostigma reticulatum

British Library Electronic Table of Contents (United Kingdom)

The leaf extract from the plant Piliostigma reticulatum was found to exhibit antimicrobial activity against some bacteria and fungi such as Staphylococcus aureus (NCTC 6571), Escherichia coli (NCTC 10418), Bacillus subtilis (NCTC 8236), Proteus vulgaris (NCTC 4175), Aspergillus niger (ATCC 10578) and Candida albicans (ATCC 10231). Upon investigation of the chemical constituents present in the leaf extract, a total of seven compounds were isolated and their structures were unambiguously established by spectroscopic methods including HR-MS and NMR spectrometry. Four of the isolated compounds were novel, namely 6-C-methyl-2-p-hydroxyphenyloxychromonol (piliostigmol), 1, 6,8-di-C-methylquercetin-3,3prime,7-trimethyl ether, 2, 6,8-di-C-methylquercetin-3,3prime-dimethyl ether, 3 and 3prime,6,8,-...

2008-01-01

Enhanced antibacterial activity of bifunctional Fe3O4-Ag core-shell nanostructures

British Library Electronic Table of Contents (United Kingdom)

We describe a simple one-pot thermal decomposition method for the production of a stable colloidal suspension of narrowly dispersed superparamagnetic Fe3O4-Ag core-shell nanostructures. These biocompatible nanostructures are highly toxic to microorganisms. Antimicrobial activity studies were carried out on both Gram negative (Escherichia coli and Proteus vulgaris) and Gram positive (Bacillus megaterium and Staphylococcus aureus) bacterial strains. Efforts have been made to understand the underlying molecular mechanism of such antibacterial actions. The effect of the core-shell nanostructures on Gram negative strains was found to be better than that observed for silver nanoparticles. The minimum inhibitory concentration (MIC) values of these nanostructures were found to be considerably lowe...

2009-01-01

100

Australian experience with herbicide tolerant (HT) and Bacillus thuringiensis (Bt) cotton

British Library Electronic Table of Contents (United Kingdom)

Australia?s nationally consistent framework for gene technology regulation is underpinned by the Gene Technology Act 2000, administered by an independent decision-maker, the Gene Technology Regulator. The object of the Act is ?to protect the health and safety of people, and to protect the environment, by identifying risks posed by or as a result of gene technology, and by managing those risks through regulating certain dealings with genetically modified organisms?. Marketing and trade impacts are outside the scope of assessments required by the Act. Since 2001, seven licences have been issued for the commercial cultivation of genetically modified (GM) cotton with insect resistance and/or herbicide tolerance. Licences have also been issued for 32 GM cotton field trials with a broader range ...

2011-01-01

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101

Aerobic Decolorization and Detoxification of a Disperse Dye in Textile Effluent by a New Isolate of Bacillus sp.

British Library Electronic Table of Contents (United Kingdom)

A number of aerobic species capable of decolorizing some of the dyes in a textile mill effluent were isolated. One of the isolates was able to decolorize Terasil black dye under aerobic conditions in the presence of an exogenous carbon source after 5 days. Glucose or starch (%1 ea) are essential for decolorization but the process proceeds faster in the presence of 0.5% yeast extract. Results of the BOD5 show that the untreated effluent samples have a low BOD value, whereas treated samples show an initial increase in BOD up to 15 days followed by a decrease after 20 days. FT-IR and GC-MS data also reveal that the initial components in the untreated effluent disappear after 20 days of treatment, confirming biodegradation of the dye. Phytotoxicity tests on the untreated effluent samples using...

2006-01-01

102

Testing an agent-based model of bacterial cell motility: How nutrient concentration affects speed distribution

British Library Electronic Table of Contents (United Kingdom)

We revisit a recently proposed agent-based model of active biological motion and compare its predictions with own experimental findings for the speed distribution of bacterial cells, Salmonella typhimurium. Agents move according to a stochastic dynamics and use energy stored in an internal depot for metabolism and active motion. We discuss different assumptions of how the conversion from internal to kinetic energy d(v) may depend on the actual speed, to conclude that d 2 v ? with either ? = 2 or 1 ? < 2 are promising hypotheses. To test these, we compare the model?s prediction with the speed distribution of bacteria which were obtained in media of different nutrient concentration and at different times. We find that both hypotheses are in line with the experimental observations, with ? bet...

2011-01-01

103

Susceptibility to invasive bacterial infections in children with sickle cell disease

British Library Electronic Table of Contents (United Kingdom)

Individuals with sickle cell disease (SCD) demonstrate an increased susceptibility to invasive bacterial infections (IBI). The most common organisms causing IBI are Streptococcus pneumoniae, nontyphi Salmonella species and Haemophilus influenzae type b (Hib). IBI are the most common causes of death in children below 5 years of age with SCD. Increased susceptibility to IBI is because of several factors including dysfunctional antibody production and opsonophagocytosis as well as defective splenic clearance. Early diagnosis of Hib and pneumococcal infections combined with antibiotic prophylaxis and immunization programs, could lead to significant improvements in mortality, especially in Africa. Pediatr Blood Cancer. 2010;55:401-406. Copyright 2010 Wiley-Liss, Inc.

2010-01-01

104

Microbial pathogens in raw pork, chicken, and beef: benefit estimates for control using irradiation

Detection of irradiated chicken by ESR spectroscopy of bone

Various control procedures have been suggested for reducing foodborne infectious diseases. Receiving considerable attention is irradiation. This report estimates the medical and wage (or productivity) benefits associated with prevention of five human diseases transmitted by beef, pork, and chicken. (These diseases can also be transmitted by other vectors, such as eggs, milk, and pets. But these sources are not included in the analysis.) All of these foodborne infectious diseases - salmonellosis, campylobacteriosis, trichinosis, tapeworm, and toxoplasmosis - could be significantly reduced by irradiating meat and poultry. The Food and Drug Administration (FDA) has just approved irradiation of pork to prevent trichinosis (50FR 29658-59) and is considering approval of irradiation of chicken to kill Salmonella. 22 references.

1985-12-01

105

The role of the HCR system in the repair of lethal lesions of Bacillus subtilis phages and their transfecting DNA damaged by radiation and alkylating agents

Ionizing radiation has been used to treat poultry to remove harmful microorganisms, mainly Salmonella, which contaminates chicken, goose and other fresh and frozen poultry. This microorganism is sensitive to low dose radiation. Thus, irradiating these foods with doses between 1 to 7 kGy results in a large reduction of bacteria. Since it is necessary to determine whether irradiation has occurred and to what extend, this work studied the signal produced by ionizing radiation within the hard crystalline matrix of chicken`s bone to establish a control method. Chicken`s drumsticks were irradiated and bones separated from flesh were lyophilized and milled. ESR spectrum was then obtained. The ESR signal increased linearly with dose over the range 0.25 to 8.0 kGy. Free radicals evaluated during 30 days after irradiation showed stable in this period. (Author).

1995-10-01

106

Risk Assessment and Ecological Effects of Transgenic Bacillus thuringiensis Crops on Non-Target Organisms(F).

The role of the HCR system in the repair of prelethal lesions induced by UV light, #gamma# radiation and alkylating agents was studied in the Bacillus subtilis SPP1 phage, its heat sensitive mutants (N3, N73 nad ts_1) and corresponding infectious DNA. The survival of phages and their transfecting DNA after treatment with UV light is substantially higher in hcr"+ cells than in hcr cells, the differences being more striking in intact phages than in their transfecting DNA's. Repair inhibitors reduce survival in hcr"+ cells: caffeine lowers the survival of UV-irradiated phage SPP1 in exponentially growing hcr"+ cells but has no effect on its survival in competent hcr"+ cells; acriflavin and ethidium bromide decrease the survival of the UV-irradiated SPP1 phage in both exponentially growing and competent hcr"+ cells to the level of survival observed in hcr cells; moreover, ethidium bromide lowers the number of infective centres in hcr"+ cells of the UV-irradiated DNA of ...

107

Interaction of aerobic soil bacteria with plutonium(VI)

Kong-Ming Wu (Corresponding author) The application of recombinant DNA technology has resulted in many insect-resistant varieties by genetic engineering (GE). Crops expressing Cry toxins derived from Bacillus thuringiensis (Bt) have been planted worldwide, and are an effective tool for pest control. However, one ecological concern regarding the potential effects of insect-resistant GE plants on non-target organisms (NTOs) has been continually debated. In the present study, we briefly summarize the data regarding the development and commercial use of transgenic Bt varieties, elaborate on the procedure and methods for assessing the non-target effects of insect-resistant GE plants, and synthetically analyze the related research results, mostly those published between 2005 and 2010. A mass of laboratory and field studies have shown that the currently available Bt crops have no direct detrimental effects on NTOs due to their narrow spectrum of activity, and Bt crops are ...

2011-07-01

108

Immunological correlates for protection against intranasal challenge of Bacillus anthracis spores conferred by a protective antigen-based vaccine in rabbits.

We studied the interaction of Pu(VI) with Pseudomonas stutzeri ATCC 17588 and Bacillus sphaericus ATCC 14577, representatives of the main aerobic groups of soil bacteria present in the upper soil layers. The accumulation studies have shown that these soil bacteria accumulate high amounts of Pu(VI). The sorption efficiency toward Pu(VI) decreased with increasing biomass concentration due to increased agglomeration of the bacteria resulting in a decreased total surface area and number of available complexing groups. Spores of Bacillus sphaericus showed a higher biosorption than the vegetative cells at low biomass concentration which decreased significantly with increasing biomass concentration. At higher biomass concentrations (> 0.7 g/L), the vegetative cells of both strains and the spores of B. sphaericus showed comparable sorption efficiencies. Investigations on the pH dependency of the biosorption and extraction studies with 0.01 M ...

2000-08-22

109

Murine antibody response to oral infection with live aroA recombinant Salmonella dublin vaccine strains expressing filamentous hemagglutinin antigen from Bordetella pertussis.

Correlates between immunological parameters and protection against Bacillus anthracis infection in animals vaccinated with protective antigen (PA)-based vaccines could provide surrogate markers to evaluate the putative protective efficiency of immunization in humans. In previous studies we demonstrated that neutralizing antibody levels serve as correlates for protection in guinea pigs (S. Reuveny et al., Infect. Immun. 69:2888-2893, 2001; H. Marcus et al., Infect. Immun. 72:3471-3477, 2004). In this study we evaluated similar correlates for protection by active and passive immunization of New Zealand White rabbits. Full immunization and partial immunization were achieved by single and multiple injections of standard and diluted doses of a PA-based vaccine. Passive immunization was carried out by injection of immune sera from rabbits vaccinated with PA-based vaccine prior to challenge with B. anthracis spores. Immunized rabbits were challenged by intranasal spore ...

2006-01-01

110

An investigation of some Turkish herbal medicines in Salmonella typhimurium and in the COMET assay in human lymphocytes.

Two plasmids which express either nearly intact or truncated filamentous hemagglutinin (FHA) from Bordetella pertussis and which are marked with a tetracycline resistance (Tcr) gene were transformed into Salmonella dublin SL1438, an aroA deletion mutant intended for use as an attenuated oral vaccine against salmonellosis. These S. dublin recombinants, when fed to mice, induced serum immunoglobulin, immunoglobulin M (IgM), and sometimes IgA antibody responses to FHA and S. dublin. In addition, IgA antibodies against FHA were found in gut wash fluids. S. dublin carrying pDB2300, a multicopy plasmid encoding truncated FHA protein, induced a better antibody response than did S. dublin carrying pDB2000, a low-copy-number plasmid encoding full-sized FHA. Administration of tetracycline to mice enhanced the stability of recombinant plasmids, and tetracycline-treated mice developed higher anti-FHA titers. Although neither strain examined is suitable for use in a human oral ...

1990-08-01

111

Synthesis, characterization and biological evaluation of mononuclear Co(II), Ni(II), Cu(II) and Pd(II) complexes with new N2O2 Schiff base ligands.

Medicinal plants play a major role in the life of Turkish people and of late medicinal plant usage has increased in many countries. Green plants in general contain mutagenic and carcinogenic substances, but there is little information about the biological activities of herbal medicine. In the present study, therefore, various Turkish medicinal herbs were investigated for their genotoxic potential in the Salmonella typhimurium microsomal activation assay and the alkaline single cell gel electrophoresis (COMET) assay. Extracts from these medicinal herbs and some fractions of these extracts were examined. The species investigated were Arctium minus, Ecballium elatterium, Momordica charantia, Plantago major, Urtica dioica, Viscum album, Salvia triloba, Euphorbia rigida, Stachys lavandulifolia, Acteoside, Abies nordmannia. They are used for various immune disorders and are applied either topically or taken orally as a herbal tea. Of the 19 samples of the extracts and ...

1996-01-01

112

USE OF A CONTROLLED CHLORINE DIOXIDE (CLO2) RELEASE SYSTEM IN COMBINATION WITH MODIFIED ATMOSPHERE PACKAGING (MAP) TO CONTROL THE GROWTH OF PATHOGENS

New tetradentate N(2)O(2) donor Schiff bases and their mononuclear Co(II), Ni(II), Cu(II), and Pd(II) complexes were synthesized and characterized extensively by IR, (1)H-, (13)C-NMR, mass, ESR, conductivity measurements, elemental and thermal analysis. Specifically the magnetic and electronic spectral measurements demonstrate the octahedral structures of cobalt(II), nickel(II) complexes and square planar geometries of copper(II), palladium(II) complexes. All the ligands and complexes were screened for their in vitro antibacterial activity against two gram-positive bacteria (Bacillus subtilis, Staphylococcus aureus) and two gram-negative bacteria (Escherichia coli, Klebsiella pneumonia). In this study, Pd(II) complexes exhibited potent antibacterial activity against B. subtilis, S. aureus whereas other metal complexes also exerted good activity towards all tested strains even than standard drugs streptomycin and ampicillin. PMID:21297294

2011-02-01

113

British Library Electronic Table of Contents (United Kingdom)

Abstract Salmonella Typhimurium and Listeria monocytogenes are major bacterial pathogens associated with poultry products. A controlled released ClO2 sachet applied with modified atmosphere packaging (MAP) was evaluated for its ability to control the growth of S. Typhimurium and L. monocytogenes on raw chicken breast during refrigerated storage. The fresh chicken samples were inoculated with one or the other of the pathogens at 104-cfu/g, and the packages (with and without ClO2 sachet) were flushed with ambient air or 30% CO2/70% N2 before sealing, and then stored at 4C for up to 21 days. The maximum reduction in MAP plus ClO2 (compared with MAP alone) was 0.68-log-cfu/g for S. Typhimurium and 1.87-log-cfu/g for L. monocytogenes. Color and pH changes of the chicken breast were observed at ...

2011-01-01

114

Negative Ames-test of cis-di(thiocyanato)-N,N'-bis(4,4'-dicarboxy-2,2'-bipyridine)Ru(II), the sensitizer dye of the nanocrystalline TiO{sub 2} solar cell

Antioxidant and toxicity tests of roasted noni (Morinda citrifolia) leaf infusion

Dye-sensitized nanocrystalline TiO{sub 2} solar cells are currently under development. Since these cells contain an electrolyte solution we reviewed the health and safety aspects in view of indoor applications, where personal contact cannot be excluded. Only small amounts of chemicals are present in each cell and so there is no danger of acute toxicity. However, long-term effects often can be caused by incidental contact with minute amounts. For this reason we have tested cis-di(thiocyanato)-bis(4,4'-dicarboxy-2,2'-bipyridine)Ru(II), the sensitizer dye in the Ames test. The dye was not mutagenic in the Salmonella typhimurium reverse mutation assay and in the Escherichia coli reverse mutation assay.

2000-01-01

115

British Library Electronic Table of Contents (United Kingdom)

Summary The antioxidant properties and toxicity profile of roasted noni (Morinda citrifolia L.) leaf infusion were evaluated. The 2,2-diphenylpicrylhydrazyl (DPPH) radical scavenging activity was greater than green tea infusion (81.6 +- 0.9% vs. 57.5 +- 1.8%, P < 0.001). The mean quercetin and kaempferol contents of roasted noni leaf infusion, as prepared by the consumer, were 0.24 +- 0.01 and 0.14 +- 0.01 mg mL-1, respectively. Tannic acid content was 10 +- 1 mg mL-1. The infusion was non-mutagenic in the reverse mutation test in Salmonella typhimurium and did not induce primary DNA damage in E. coli PQ37. Further, no significant primary DNA damage was induced by 5,15-dimethylmorindol, which was the only detectable anthraquinone in noni leaves. The infusion was not cytotoxic in the 24 h b...

2009-01-01

116

Active packaging of ground beef patties by edible zein films incorporated with partially purified lysozyme and Na2EDTA

British Library Electronic Table of Contents (United Kingdom)

Summary In this study, antimicrobial activity of zein films incorporated with partially purified lysozyme and disodium ethylenediaminetetraacetic acid (Na2EDTA) has been tested on selected pathogenic bacteria and refrigerated ground beef patties. The developed films containing 700-g-cm-2 lysozyme and 300-g-cm-2 Na2EDTA showed antimicrobial activity on Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella typhimurium. The application of lysozyme and Na2EDTA incorporated zein films on beef patties significantly decreased total viable counts (TVC) and total coliform counts after 5-days of storage compared to those of control patties (P-2EDTA or Na2EDTA alone significantly slowed down the oxidative changes in patties during storage (P-P-2EDTA for active packaging of refrigerated mea...

2011-01-01

117

Atomic substitution reveals the structural basis for substrate adenine recognition and removal by adenine DNA glycosylase

Safety evaluation of Propionibacterium freudenreichii ET-3 culture.

Adenine DNA glycosylase catalyzes the glycolytic removal of adenine from the promutagenic A {center_dot} oxoG base pair in DNA. The general features of DNA recognition by an adenine DNA glycosylase, Bacillus stearothermophilus MutY, have previously been revealed via the X-ray structure of a catalytically inactive mutant protein bound to an A:oxoG-containing DNA duplex. Although the structure revealed the substrate adenine to be, as expected, extruded from the DNA helix and inserted into an extrahelical active site pocket on the enzyme, the substrate adenine engaged in no direct contacts with active site residues. This feature was paradoxical, because other glycosylases have been observed to engage their substrates primarily through direct contacts. The lack of direct contacts in the case of MutY suggested that either MutY uses a distinctive logic for substrate recognition or that the X-ray structure had captured a noncatalytically competent state in lesion ...

2010-01-14

118

Effects of alpha-deuterium substitution on the mutagenicity of 4-(methyl-nitrosamino)-1-(3-pyridyl)-1-butanone (NNK)

Propionibacterium freudenreichii ET-3 culture, a cell-free product of whey fermentation using P. freudenreichii ET-3 (7025), has been shown to promote the growth of Bifidobacteria through the action of 1,4-dihydroxy-2-naphthoic acid (DHNA), and therefore, has potential use in the food and supplement industries. Although currently used as a food ingredient in Japan, the safety of this novel ingredient has not been previously evaluated through traditional toxicity testing. Therefore, here we report the results of standard toxicological testing performed on P. freudenreichii ET-3 culture. In a 4-week oral toxicity study, administration of 6000mg/kg body weight/day P. freudenreichii ET-3 culture was without compound-related adverse effects on clinical signs, body weights, food consumption, ophthalmology, hematology, clinical chemistry, urinalysis, organ weights, and gross and microscopic findings in male and female Sprague-Dawley rats. Furthermore, in vitro mutagenicity testing ...

2011-03-22

119

Depuration of shellfish by irradiation: Final technical report, October 1, 1987--March 31, 1989

4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), a carcinogenic tobacco specific nitrosamine, can be converted to electrophilic diazohydroxide intermediates by metabolic hydroxylation of either the methylene carbon (carbon 4) or the methyl carbon attached to the nitrosamine group. To investigate the relative importance of these two processes in NNK mutagenesis, we synthesized 4,4-dideutero-4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone((4,4,-D2)NNK) and 4-(trideuteromethylnitrosamino)-1-(3-pyridyl)-1-butanone ((CD3) NNK), and evaluated their mutagenic activities in Salmonella typhimurium tester strains. In the presence of Aroclor induced rat liver 9000 g supernatant, NNK and (4,4-D2)NNK had comparable mutagenic activities towards S. typhimurium TA 1535 and TA 100, but (CD3)NNK was inactive in both strains. These results suggest that hydroxylation of the methyl group of NNK is more important than hydroxylation of carbon 4 in its activation to a mutagen. To test ...

1983-01-01

120

Chemical, sensory and microbiological changes of gamma irradiated coconut cream powder

Studies by the University of Lowell Radiation Laboratory and the US National Marine Fisheries Service N.E. Laboratory in Gloucester, MA on softshelled clams (Mya arenaria) demonstrated the effectiveness of low to medium doses of Cobalt 60 source gamma irradiation in the inactivation of Escherichia coli, Salmonella typhimurium, Staphylococcus aureus and Streptococcus faecalis. Post-irradiation survival and organoleptic studies when extended to hardshelled clams (Mercinaria mercenaria) and American oysters (Crassostrea virginica) showed no significant decline in consumer qualities or 6 day post irradiation survival in oysters at doses of up to 3.0 kGy. The capacities of the American oyster to sustain relatively high doses of gamma irradiation were demonstrated by 6 day post-exposure survivorship values of greater than 90% for samples receiving 3.0, 5.0 and 7.0 kGy. Initial studies of inactivation of Polio I virus and a simian rotavirus (SA-11) was conducted in both ...

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121

Regulation of the pT181 encoded tetracycline resistance gene in Straphylococcus aureus

A study was carried out to determine optimum decontamination dose for a locally manufactured coconut cream powder. Samples were gamma irradiated (0-15 kGy) and ageing process was achieved using GEER oven at 60 deg. C for 7 days, which is equivalent to one-year storage at room temperature. Iodine value (IV), ranging from 4.8 to 6.4, was not affected by radiation doses and storage, however peroxide value and thiobarbituric acid (TBA) generally increased with radiation doses. In most samples, peroxide value (meq/kg) reduced after storage, whilst the TBA (mg malonaldehyde/kg), indicator for product quality, slightly increased. The sensory evaluation conducted using 25 taste panellists indicated that scores on odour, creamy taste and overall acceptance for all irradiated samples at more than 5 kGy were significantly lower (P<0.05) than the control. However, the panellists could not detect any significant differences among the irradiation doses (P>0.05). All stored products ...

2007-11-15

122

Interaction of antimicrobial peptides with lipid membranes

pT181 is a naturally-occurring 4437 basepair (bp) plasmid isolated from Staphylococcus aureus which encodes inducible resistance to tetracycline (Tc). The DNA sequence data has identified three open reading frames (ORFs). The largest ORF B, has been found to be responsible for the Tc resistance phenotype of pT181. Since most Tc resistance systems appear to be regulated by an effector protein and a repressor protein, several Bal 31 deletion mutants of pT181 were constructed and analyzed in an effort to identify the elements involved in Tc resistance. Two transcomplementing groups of mutants were identified within the tet gene. The mechanism of Tc resistance was studied by assaying the accumulation of (7-/sup 3/H) Tc by Tc sensitive cells, and uninduced and induced pT181-containing cells. A sharp decrease in accumulation of the drug after an initial increase was observed in Tc induced pT181-containing cells. In vivo labeling of Bacillus subtilis minicells containing ...

1986-01-01

123

Integrated systems for control of pink bollworm in cotton

This study aims to investigate the difference in the interaction of antimicrobial peptides with two classes of zwitterionic peptides, phosphatidylethanolamines (PE) and phosphatidylcholines (PC). Further experiments were performed on model membranes prepared from specific bacterial lipids, lipopolysaccharides (LPS) isolated from Salmonella minnesota. The structure of the lipid-peptide aqueous dispersions was studied by small-and wide-angle X-ray diffraction during heating and cooling from 5 to 85 C. The lipids and peptides were mixed at lipid-to-peptide ratios 10-10000 (POPE and POPC) or 2-50 (LPS). All experiments were performed at synchrotron soft condensed matter beamline A2 in Hasylab at Desy in Hamburg, Germany. The phases were identified and the lattice parameters were calculated. Alamethicin and melittin interact in similar ways with the lipids. Pure POPC forms only lamellar phases. POPE forms lamellar phases at low temperatures that upon heating transform ...

124