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aminoimidazole carboxamide ribotide exerts opposing effects on thiamine synthesis in salmonella enterica.in salmonella enterica, the thiamine biosynthetic intermediate 5-aminoimidazole ribotide (air) can be synthesized de novo independently of the early purine biosynthetic reactions. this secondary route to air synthesis is dependent on (i) 5-amino-4-imidazolecarboxamide ribotide (aicar) accumulation, (ii) a functional phosphoribosylaminoimidazole-succinocarboxamide (saicar) synthetase (purc; ec 6.3.2.6), and (iii) methionine and lysine in the growth medium. studies presented here show that aicar i ...201526100042
the outer membrane protease pgte of salmonella enterica interferes with the alternative complement pathway by cleaving factors b and h.the virulence factor pgte is an outer membrane protease (omptin) of the zoonotic pathogen salmonella enterica that causes diseases ranging from gastroenteritis to severe enteric fever. it is surface exposed in bacteria that have a short-chain, i.e., rough lps, as observed e.g., in bacteria residing inside macrophages or just emerging from them. we investigated whether pgte cleaves the complement factors b (b) and h (h), key proteins controlling formation and inactivation of the complement protei ...201525705210
poultry body temperature contributes to invasion control through reduced expression of salmonella pathogenicity island 1 genes in salmonella enterica serovars typhimurium and enteritidis.salmonella enterica serovars typhimurium (s. typhimurium) and enteritidis (s. enteritidis) are foodborne pathogens, and outbreaks are often associated with poultry products. chickens are typically asymptomatic when colonized by these serovars; however, the factors contributing to this observation are uncharacterized. whereas symptomatic mammals have a body temperature between 37°c and 39°c, chickens have a body temperature of 41°c to 42°c. here, in vivo experiments using chicks demonstrated that ...201526386070
the development and evaluation of a loop-mediated isothermal amplification method for the rapid detection of salmonella enterica serovar typhi.typhoid fever remains a public health threat in many countries. a positive result in traditional culture is a gold-standard for typhoid diagnosis, but this method is time consuming and not sensitive enough for detection of samples containing a low copy number of the target organism. the availability of the loop-mediated isothermal amplification (lamp) assay, which offers high speed and simplicity in detection of specific targets, has vastly improved the diagnosis of numerous infectious diseases. ...201525910059
plant pathogen-induced water-soaking promotes salmonella enterica growth on tomato leaves.plant pathogen infection is a critical factor for the persistence of salmonella enterica on plants. we investigated the mechanisms responsible for the persistence of s. enterica on diseased tomato plants by using four diverse bacterial spot xanthomonas species that differ in disease severities. xanthomonas euvesicatoria and x. gardneri infection fostered s. enterica growth, while x. perforans infection did not induce growth but supported the persistence of s. enterica. x. vesicatoria-infected le ...201526386057
cilantro microbiome before and after nonselective pre-enrichment for salmonella using 16s rrna and metagenomic sequencing.salmonella enterica is a common cause of foodborne gastroenteritis in the united states and is associated with outbreaks in fresh produce such as cilantro. salmonella culture-based detection methods are complex and time consuming, and improvments to increase detection sensitivity will benefit consumers. in this study, we used 16s rrna sequencing to determine the microbiome of cilantro. we also investigated changes to the microbial community prior to and after a 24-hour nonselective pre-enrichmen ...201526264042
a diverse range of bacterial and eukaryotic chitinases hydrolyzes the lacnac (galβ1-4glcnac) and lacdinac (galnacβ1-4glcnac) motifs found on vertebrate and insect cells.there is emerging evidence that chitinases have additional functions beyond degrading environmental chitin, such as involvement in innate and acquired immune responses, tissue remodeling, fibrosis, and serving as virulence factors of bacterial pathogens. we have recently shown that both the human chitotriosidase and a chitinase from salmonella enterica serovar typhimurium hydrolyze lacnac from galβ1-4glcnacβ-tetramethylrhodamine (lacnac-tmr (galβ1-4glcnacβ(ch2)8conh(ch2)2nhco-tmr)), a fluorescen ...201525561735
real-time duplex applications of loop-mediated amplification (lamp) by assimilating probes.isothermal nucleic-acid amplification methods such as loop-mediated isothermal amplification (lamp) are increasingly appealing alternatives to pcr for use in portable diagnostic system due to the low cost, weight, and power requirements of the instrumentation. as such, interest in developing new probes and other functionality based on the lamp reaction has been intense. here, we report on the development of duplexed lamp assays for pathogen detection using spectrally unique assimilating probes. ...201525741765
phylogenetic and amino acid conservation analyses of bacterial l-aspartate-α-decarboxylase and of its zymogen-maturation protein reveal a putative interaction domain.all organisms must synthesize the enzymatic cofactor coenzyme a (coa) from the precursor pantothenate. most bacteria can synthesize pantothenate de novo by the condensation of pantoate and β-alanine. the synthesis of β-alanine is catalyzed by l-aspartate-α-decarboxylase (pand), a pyruvoyl enzyme that is initially synthesized as a zymogen (pro-pand). active pand is generated by self-cleavage of pro-pand at gly24-ser25 creating the active-site pyruvoyl moiety. in salmonella enterica, this cleavage ...201526276430
intra- and inter-species interactions within biofilms of important foodborne bacterial pathogens.a community-based sessile life style is the normal mode of growth and survival for many bacterial species. under such conditions, cell-to-cell interactions are inevitable and ultimately lead to the establishment of dense, complex and highly structured biofilm populations encapsulated in a self-produced extracellular matrix and capable of coordinated and collective behavior. remarkably, in food processing environments, a variety of different bacteria may attach to surfaces, survive, grow, and for ...201526347727
genomic targets and features of bara-uvry (-sira) signal transduction systems.the two-component signal transduction system bara-uvry of escherichia coli and its orthologs globally regulate metabolism, motility, biofilm formation, stress resistance, virulence of pathogens and quorum sensing by activating the transcription of genes for regulatory srnas, e.g. csrb and csrc in e. coli. these srnas act by sequestering the rna binding protein csra (rsma) away from lower affinity mrna targets. in this study, we used chip-exo to identify, at single nucleotide resolution, genomic ...201526673755
regulation of dna phosphorothioate modification in salmonella enterica by dndb.dna phosphorothioate (pt) modification, in which the non-bridging oxygen of the sugar-phosphate backbone is substituted by sulfur, occurs naturally in diverse bacteria and archaea and is regulated by the dndabcde proteins. dndabcde and the restriction cognate dndfghi constitute a new type of defense system that prevents the invasion of foreign dna in salmonella enterica serovar cerro 87. gaac/gttc consensus contexts across genomes were found to possess partial pt modifications even in the presen ...201526190504
de novo amino acid biosynthesis contributes to salmonella enterica growth in alfalfa seedling exudates.salmonella enterica is a member of the plant microbiome. growth of s. enterica in sprouting-seed exudates is rapid; however, the active metabolic networks essential in this environment are unknown. to examine the metabolic requirements of s. enterica during growth in sprouting-seed exudates, we inoculated alfalfa seeds and identified 305 s. enterica proteins extracted 24 h postinoculation from planktonic cells. over half the proteins had known metabolic functions, and they are involved in over o ...201525416761
structural features reminiscent of atp-driven protein translocases are essential for the function of a type iii secretion-associated atpase.many bacterial pathogens and symbionts utilize type iii secretion systems to interact with their hosts. these machines have evolved to deliver bacterial effector proteins into eukaryotic target cells to modulate a variety of cellular functions. one of the most conserved components of these systems is an atpase, which plays an essential role in the recognition and unfolding of proteins destined for secretion by the type iii pathway. here we show that structural features reminiscent of other atp-d ...201526170413
the diagnostic accuracy of three rapid diagnostic tests for typhoid fever at chittagong medical college hospital, chittagong, bangladesh.to determine the diagnostic accuracy of three rapid diagnostic tests (rdts) for typhoid fever in febrile hospitalised patients in bangladesh.201526094960
inhibition of pathogenic and spoilage bacteria by a novel biofilm-forming lactobacillus isolate: a potential host for the expression of heterologous proteins.bacterial biofilms are a preferred mode of growth for many types of microorganisms in their natural environments. the ability of pathogens to integrate within a biofilm is pivotal to their survival. the possibility of biofilm formation in lactobacillus communities is also important in various industrial and medical settings. lactobacilli can eliminate the colonization of different pathogenic microorganisms. alternatively, new opportunities are now arising with the rapidly expanding potential of ...201526150120
a macrophage subversion factor is shared by intracellular and extracellular pathogens.pathogenic bacteria have developed strategies to adapt to host environment and resist host immune response. several intracellular bacterial pathogens, including salmonella enterica and mycobacterium tuberculosis, share the horizontally-acquired mgtc virulence factor that is important for multiplication inside macrophages. mgtc is also found in pathogenic pseudomonas species. here we investigate for the first time the role of mgtc in the virulence of an extracellular pathogen, pseudomonas aerugin ...201526080006
conjunctival flora of clinically normal and diseased turtles and tortoises.in captive breed turtles and tortoises conjunctival disease is common. our aim was to investigate the bacterial and fungal flora present in the eyes of healthy and pathological chelonians and to compare findings in turtles with those in tortoises.201525889261
temperature-sensitive salmonella enterica serovar enteritidis pt13a expressing essential proteins of psychrophilic bacteria.synthetic genes based on deduced amino acid sequences of the nad-dependent dna ligase (liga) and ctp synthetase (pyrg) of psychrophilic bacteria were substituted for their native homologues in the genome of salmonella enterica serovar enteritidis phage type 13a (pt13a). the resulting strains were rendered temperature sensitive (ts) and did not revert to temperature resistance at a detectable level. at permissive temperatures, ts strains grew like the parental strain in broth medium and in macrop ...201526187965
structure of aada from salmonella enterica: a monomeric aminoglycoside (3'')(9) adenyltransferase.aminoglycoside resistance is commonly conferred by enzymatic modification of drugs by aminoglycoside-modifying enzymes such as aminoglycoside nucleotidyltransferases (ants). here, the first crystal structure of an ant(3'')(9) adenyltransferase, aada from salmonella enterica, is presented. aada catalyses the magnesium-dependent transfer of adenosine monophosphate from atp to the two chemically dissimilar drugs streptomycin and spectinomycin. the structure was solved using selenium sad phasing and ...201526527143
development of a protocol for predicting bacterial resistance to microbicides.regulations dealing with microbicides in europe and the united states are evolving and now require data on the risk of the development of resistance in organisms targeted by microbicidal products. there is no standard protocol to assess the risk of the development of resistance to microbicidal formulations. this study aimed to validate the use of changes in microbicide and antibiotic susceptibility as initial markers for predicting microbicide resistance and cross-resistance to antibiotics. thre ...201525636848
the extended regulatory networks of sxt/r391 integrative and conjugative elements and inca/c conjugative plasmids.nowadays, healthcare systems are challenged by a major worldwide drug resistance crisis caused by the massive and rapid dissemination of antibiotic resistance genes and associated emergence of multidrug resistant pathogenic bacteria, in both clinical and environmental settings. conjugation is the main driving force of gene transfer among microorganisms. this mechanism of horizontal gene transfer mediates the translocation of large dna fragments between two bacterial cells in direct contact. inte ...201526347724
small rna-based feedforward loop with and-gate logic regulates extrachromosomal dna transfer in salmonella.horizontal gene transfer via plasmid conjugation is a major driving force in microbial evolution but constitutes a complex process that requires synchronization with the physiological state of the host bacteria. although several host transcription factors are known to regulate plasmid-borne transfer genes, rna-based regulatory circuits for host-plasmid communication remain unknown. we describe a posttranscriptional mechanism whereby the hfq-dependent small rna, rpra, inhibits transfer of pslt, t ...201526307765
development and validation of a high-throughput cell-based screen to identify activators of a bacterial two-component signal transduction system.cpxra is a two-component signal transduction system (2csts) found in many drug-resistant gram-negative bacteria. in response to periplasmic stress, cpxa autophosphorylates and donates a phosphoryl group to its cognate response regulator, cpxr. phosphorylated cpxr (cpxr-p) upregulates genes involved in membrane repair and downregulates multiple genes that encode virulence factors, which are trafficked across the cell membrane. mutants that constitutively activate cpxra in salmonella enterica sero ...201525870061
genome rearrangements can make and break small rna genes.small rnas (srnas) are short, transcribed regulatory elements that are typically encoded in the intergenic regions (igrs) of bacterial genomes. several srnas, first recognized in escherichia coli, are conserved among enteric bacteria, but because of the regulatory roles of srnas, differences in srna repertoires might be responsible for features that differentiate closely related species. we scanned the e. coli mg1655 and salmonella enterica typhimurium genomes for nonsyntenic igrs as a potential ...201525601101
development of a taqman array card for acute-febrile-illness outbreak investigation and surveillance of emerging pathogens, including ebola virus.acute febrile illness (afi) is associated with substantial morbidity and mortality worldwide, yet an etiologic agent is often not identified. convalescent-phase serology is impractical, blood culture is slow, and many pathogens are fastidious or impossible to cultivate. we developed a real-time pcr-based taqman array card (tac) that can test six to eight samples within 2.5 h from sample to results and can simultaneously detect 26 afi-associated organisms, including 15 viruses (chikungunya, crime ...201526491176
monoclonal antibodies of a diverse isotype induced by an o-antigen glycoconjugate vaccine mediate in vitro and in vivo killing of african invasive nontyphoidal salmonella.nontyphoidal salmonella (nts), particularly salmonella enterica serovars typhimurium and enteritidis, is responsible for a major global burden of invasive disease with high associated case-fatality rates. we recently reported the development of a candidate o-antigen-crm197 glycoconjugate vaccine against s. typhimurium. here, using a panel of mouse monoclonal antibodies generated by the vaccine, we examined the relative efficiency of different antibody isotypes specific for the o:4 antigen of s. ...201526169269
presumable role of outer membrane proteins of salmonella containing sialylated lipopolysaccharides serovar ngozi, sv. isaszeg and subspecies arizonae in determining susceptibility to human serum.the o48 group comprises salmonella bacteria containing sialic acid in the lipopolysaccharide (lps). bacteria with sialylated surface structures are described as pathogens that avoid immunological response of the host by making similar their surface antigens to the host's tissues (molecular mimicry). it is known that the smooth-type lps of salmonella enterica and outer membrane proteins (omp) pgte, pagc and rck mediate serum resistant phenotype by affecting complement system (c). the aim of this ...201526185527
signatures of adaptation in human invasive salmonella typhimurium st313 populations from sub-saharan africa.two lineages of salmonella enterica serovar typhimurium (s. typhimurium) of multi-locus sequence type st313 have been linked with the emergence of invasive salmonella disease across sub-saharan africa. the expansion of these lineages has a temporal association with the hiv pandemic and antibiotic usage. we analysed the whole genome sequence of 129 st313 isolates representative of the two lineages and found evidence of lineage-specific genome degradation, with some similarities to that observed i ...201525803844
influence of salmonella enterica serovar typhimurium ssrb on colonization of eastern oysters (crassostrea virginica) as revealed by a promoter probe screen.although salmonella has been isolated from 7.4 to 8.6% of domestic raw oysters, representing a significant risk for food-borne illness, little is known about the factors that influence their initial colonization by salmonella. this study tested the hypothesis that specific regulatory changes enable a portion of the invading salmonella population to colonize oysters. an in vivo promoter probe library screen identified 19 unique regions as regulated during colonization. the mutants in the nearest ...201526497459
exposure to sub-inhibitory concentrations of cefotaxime enhances the systemic colonization of salmonella typhimurium in balb/c mice.it has been proposed that sub-inhibitory concentrations of antibiotics play a role in virulence modulation. in this study, we evaluated the ability of salmonella enterica serovar typhimurium (hereafter s. typhimurium) to colonize systemically balb/c mice after exposure to a sub-inhibitory concentration of cefotaxime (ctx). in vivo competition assays showed a fivefold increase in systemic colonization of ctx-exposed bacteria when compared to untreated bacteria. to identify the molecular mechanism ...201526468132
deciphering the regulatory circuitry that controls reversible lysine acetylation in salmonella enterica.in salmonella enterica, the reversible lysine acetylation (rla) system is comprised of the protein acetyltransferase (pat) and sirtuin deacetylase (cobb). rla controls the activities of many proteins, including the acetyl coenzyme a (acetyl-coa) synthetase (acs), by modulating the degree of acs acetylation. we report that iolr, a myo-inositol catabolism repressor, activates the expression of genes encoding components of the rla system. in vitro evidence shows that the iolr protein directly regul ...201526199328
effects of norspermidine and spermidine on biofilm formation by potentially pathogenic escherichia coli and salmonella enterica wild-type strains.polyamines are present in all living cells. in bacteria, polyamines are involved in a variety of functions, including biofilm formation, thus indicating that polyamines may have potential in the control of unwanted biofilm. in the present study, the effects of the polyamines norspermidine and spermidine on biofilms of 10 potentially pathogenic wild-type strains of escherichia coli serotype o103:h2, salmonella enterica subsp. enterica serovar typhimurium, and s. enterica serovar agona were invest ...201525595767
downy mildew disease promotes the colonization of romaine lettuce by escherichia coli o157:h7 and salmonella enterica.downy mildew, a plant disease caused by the oomycete bremia lactucae, is endemic in many lettuce-growing regions of the world. invasion by plant pathogens may create new portals and opportunities for microbial colonization of plants. the occurrence of outbreaks of escherichia coli o157:h7 (eco157) and salmonella enterica typhimurium (s. typhimurium) infections linked to lettuce prompted us to investigate the role of downy mildew in the colonization of romaine lettuce by these human pathogens und ...201525648408
cyclic rhamnosylated elongation factor p establishes antibiotic resistance in pseudomonas aeruginosa.elongation factor p (ef-p) is a ubiquitous bacterial protein that is required for the synthesis of poly-proline motifs during translation. in escherichia coli and salmonella enterica, the posttranslational β-lysylation of lys34 by the poxa protein is critical for ef-p activity. poxa is absent from many bacterial species such as pseudomonas aeruginosa, prompting a search for alternative ef-p posttranslation modification pathways. structural analyses of p. aeruginosa ef-p revealed the attachment o ...201526060278
clinical and microbiological features of salmonella meningitis in a south african population, 2003-2013.the clinical and microbiological characteristics of nontyphoidal salmonella (nts) meningitis in south africa, where human immunodeficiency virus (hiv) prevalence is high (approximately 15% in persons ≥15 years of age), were reviewed.201526449942
comparative growth analysis of capsulated (vi+) and acapsulated (vi-) salmonella typhi isolates in human blood.salmonella enterica serovar typhi (s. typhi) is a human restricted pathogen. it biosynthesizes a virulence capsular polysaccharide named as vi antigen. s. typhi regulates expression of genes involved in the biosynthesis of vi antigen in response to osmolarity. beside vi-positive isolates, vi-negative (acapsulated) isolates are also pathogenic. however, vi-positive isolates are more prevalent. the present study was planned to investigate comparative growth of vi-positive and vi-negative s. typhi ...201526417360
the stm4195 gene product (pans) transports coenzyme a precursors in salmonella enterica.coenzyme a (coa) is a ubiquitous coenzyme involved in fundamental metabolic processes. coa is synthesized from pantothenic acid by a pathway that is largely conserved among bacteria and eukaryotes and consists of five enzymatic steps. while higher organisms, including humans, must scavenge pantothenate from the environment, most bacteria and plants are capable of de novo pantothenate biosynthesis. in salmonella enterica, precursors to pantothenate can be salvaged, but subsequent intermediates ar ...201525645561
characterization of inci1 sequence type 71 epidemic plasmid lineage responsible for the recent dissemination of ctx-m-65 extended-spectrum β-lactamase in the bolivian chaco region.during the last decade, a significant diffusion of ctx-m-type extended-spectrum β-lactamases (esbls) was observed in commensal escherichia coli from healthy children in the bolivian chaco region, with initial dissemination of ctx-m-2, which was then replaced by ctx-m-15 and ctx-m-65. in this work, we demonstrate that the widespread dissemination of ctx-m-65 observed in this context was related to the polyclonal spreading of an inci1 sequence type 71 (st71) epidemic plasmid lineage. the structure ...201526100713
ingested salmonella enterica, cronobacter sakazakii, escherichia coli o157:h7, and listeria monocytogenes: transmission dynamics from adult house flies to their eggs and first filial (f1) generation adults.the mechanical transmission of pathogenic bacteria by synanthropic filth flies is widely recognized. while many studies report the fate and the temporospatial distribution of ingested foodborne bacteria by filth flies, there is little evidence about the transmission dynamics of ingested foodborne bacteria by adult house flies (musca domestica) to their progeny. in this study, we fed parental house fly adults with food contaminated with low, medium, and high concentrations of salmonella enterica, ...201526228457
growth kinetics of salmonella enterica in hajna tetrathionate broth, rappaport broth and modified semisolid rappaport agar.to determine the appropriate method for isolating salmonella enterica, we compared the growth of s. enterica serovars using three selective enrichment media. s. enterica was more successfully isolated from artificially contaminated fecal samples after enrichment in hajna tetrathionate broth or modified semisolid rappaport agar than in rappaport broth. since most bacteria (other than motile s. enterica) do not migrate on modified semisolid rappaport agar, the growth characteristics of s. enterica ...201526498402
inca/c plasmid carrying bla(ndm-1), bla(cmy-16), and fosa3 in a salmonella enterica serovar corvallis strain isolated from a migratory wild bird in germany.a salmonella enterica serovar corvallis strain was isolated from a wild bird in germany. this strain carried the inca/c2 prh-1238 plasmid. complete sequencing of the plasmid was performed, identifying the blandm-1, blacmy-16, fosa3, sul1, sul2, stra, strb, aac(6')-ib, aada5, apha6, teta(a), mpha, flor, dfra7, and mera genes, which confer clinically relevant resistance to most of the antimicrobial classes, including β-lactams with carbapenems, fosfomycin, aminoglycosides, co-trimoxazole, tetracyc ...201526169417
virulence gene regulation by l-arabinose in salmonella enterica.invasion of the intestinal epithelium is a critical step in salmonella enterica infection and requires functions encoded in the gene cluster known as salmonella pathogenicity island 1 (spi-1). expression of spi-1 genes is repressed by l-arabinose, and not by other pentoses. transport of l-arabinose is necessary to repress spi-1; however, repression is independent of l-arabinose metabolism and of the l-arabinose-responsive regulator arac. spi-1 repression by l-arabinose is exerted at a single tar ...201525991823
host cell type-dependent translocation and phop-mediated positive regulation of the effector ssek1 of salmonella enterica.salmonella enterica expresses two virulence-related type iii secretion systems (t3sss) encoded in salmonella pathogenicity island 1 (spi1) and spi2, respectively. ssek1 is a poorly characterized substrate of the spi2-encoded t3ss. here, we show that this effector is essential to get full virulence both in oral and intraperitoneal mice infections, in spite of not having a role in invasion or intracellular proliferation in cultured mammalian cells. in vitro, expression of ssek1 was higher in media ...201525972862
laboratory-based nationwide surveillance of antimicrobial resistance in ghana.global efforts are underway to combat antimicrobial resistance (amr). a key target in this intervention is surveillance for local and national action. data on amr in ghana are limited, and monitoring of amr is nonexistent. we sought to generate baseline data on amr, and to assess the readiness of ghana in laboratory-based surveillance. biomedical scientists in laboratories across ghana with capacity to perform bacteriological culture were selected and trained. in-house standard operating protoco ...201526604806
acquisition of the lac operon by salmonella enterica.classical bacteriological characteristics of salmonella enterica indicate that the members of this species are unable to utilize lactose as a carbon source. however, lactose-fermenting (lac+) strains of several salmonella serovars have been isolated from different foodborne outbreaks as well as different geographical regions worldwide. in the present study, we sequenced the genomes of 13 lac + s. enterica isolates and characterized the lac region, comparing it to the lac region in other enteric ...201526303940
genome sequence of salmonella enterica phage det7.det7 is a myoviridae bacteriophage that gains entry into its salmonella enterica serovar typhimurium host cells by adsorbing to o-antigen polysaccharide. we report here the complete 157,498-bp sequence of its genome. det7, together with its vi01-like relatives, are distantly related to phage t4.201525953168
characterization of foodborne outbreaks of salmonella enterica serovar enteritidis with whole-genome sequencing single nucleotide polymorphism-based analysis for surveillance and outbreak detection.salmonella enterica serovar enteritidis is a significant cause of gastrointestinal illness in the united states; however, current molecular subtyping methods lack resolution for this highly clonal serovar. advances in next-generation sequencing technologies have made it possible to examine whole-genome sequencing (wgs) as a potential molecular subtyping tool for outbreak detection and source trace back. here, we conducted a retrospective analysis of s. enteritidis isolates from seven epidemiolog ...201526269623
inhibition of salmonella enterica biofilm formation using small-molecule adenosine mimetics.biofilms have been widely implicated in chronic infections and environmental persistence of salmonella enterica, facilitating enhanced colonization of surfaces and increasing the ability of the bacteria to be transmitted to new hosts. salmonella enterica serovar typhi biofilm formation on gallstones from humans and mice enhances gallbladder colonization and bacterial shedding, while salmonella enterica serovar typhimurium biofilms facilitate long-term persistence in a number of environments impo ...201525313216
photodynamic inactivation mediated by erythrosine and its derivatives on foodborne pathogens and spoilage bacteria.the purpose of the present study was to evaluate the efficacy of photodynamic inactivation (pdi) mediated by erythrosine (ery) and its ester derivatives erythrosine methyl ester (erymet) and erythrosine butyl ester (erybut) on foodborne pathogens and spoilage bacteria. we evaluated staphylococcus aureus atcc 25923, aeromonas hydrophila atcc 7966, salmonella enterica serotype typhimurium atcc 14028, escherichia coli atcc 25922, and pseudomonas aeruginosa atcc 27853. the toxicity of all of the com ...201525925153
characterization of mannanase from bacillus circulans nt 6.7 and its application in mannooligosaccharides preparation as prebiotic.this study focused on the characterization of mannanase from bacillus circulans nt 6.7 for mannooligosaccharides (mos) production. the enzyme from b. circulans nt 6.7 was produced using defatted copra meal as a carbon source. the mannanase was purified by ultrafiltration and column chromatography of q-sepharose. the purified protein (m1) was a dimeric protein with a 40 kda subunit. the purified m1 exhibited optimum ph and temperature at ph 6.0 and 60 °c, respectively. it was activated by mn(2+,) ...201526697281
three phoma spp. synthesised novel silver nanoparticles that possess excellent antimicrobial efficacy.the authors report extracellular mycosynthesis of silver nanoparticles (agnps) by phoma capsulatum, phoma putaminum and phoma citri. the agnps thus synthesised were characterised by uv-visible spectrophotometer, fourier transform infrared spectroscopy, nanosight lm20 and transmission electron microscopy, which confirmed the synthesis of mostly spherical and polydisperse nanoparticles capped with proteins. the size of agnps was found in the range of 10-80 , 5-80 and 5-90 nm with an average size o ...201526435281
mechanistic aspects of biologically synthesized silver nanoparticles against food- and water-borne microbes.in the present study, silver nanoparticles (agnps) synthesized from aqueous leaves extract of malva crispa and their mode of interaction with food- and water-borne microbes were investigated. formation of agnps was conformed through uv-vis, fe-sem, eds, afm, and hr-tem analyses. further the concentration of silver (ag) in the reaction mixture was conformed through icp-ms analysis. different concentration of nanoparticles (1-3 mm) tested to know the inhibitory effect of bacterial pathogens such a ...201526178241
temperature and oxygen dependent metabolite utilization by salmonella enterica serovars derby and mbandaka.salmonella enterica is a zoonotic pathogen of clinical and veterinary significance, with over 2500 serovars. in previous work we compared two serovars displaying host associations inferred from isolation statistics. here, to validate genome sequence data and to expand on the role of environmental metabolite constitution in host range determination we use a phenotypic microarray approach to assess the ability of these serovars to metabolise ~500 substrates at 25°c with oxygen (aerobic conditions) ...201525798944
salmonella enterica biofilm-mediated dispersal by nitric oxide donors in association with cellulose nanocrystal hydrogels.protected by extracellular polymers, microbes within biofilms are significantly more resistant to disinfectants. current research has been instrumental in identifying nitric oxide donors and hydrogels as potential disinfectant additives. nitric oxide (no) donors are considered a very promising molecule as biofilm dispersal agents and hydrogels have recently attracted a lot of interest due to their biocompatible properties and ability to form stable thin films. when the no donor mahma nonoate was ...201526020015
biosynthesis, characterization, and antimicrobial applications of silver nanoparticles.in the present study, the strain brevibacterium frigoritolerans dc2 was explored for the efficient and extracellular synthesis of silver nanoparticles. these biosynthesized silver nanoparticles were characterized by ultraviolet-visible spectrophotometry, which detected the formation of silver nanoparticles in the reaction mixture and showed a maximum absorbance at 420 nm. in addition, field emission transmission electron microscopy revealed the spherical shape of the nanoparticles. the dynamic l ...201525848272
purification and characterization of a novel plantaricin, kl-1y, from lactobacillus plantarum kl-1.three bacteriocins from lactobacillus plantarum kl-1 were successfully purified using ammonium sulfate precipitation, cation-exchange chromatography and reverse-phase hplc. the bacteriocin peptides kl-1x, -1y and -1z had molecular masses of 3053.82, 3498.16 and 3533.16 da, respectively. all three peptides were stable at ph 2-12 and 25 °c and at high temperatures of 80 and 100 °c for 30 min and 121 °c for 15 min. however, they differed in their susceptibility to proteolytic enzymes and their inhi ...201525862353
antibiotic-resistant bacteria: prevalence in food and inactivation by food-compatible compounds and plant extracts.foodborne antibiotic-resistant pathogenic bacteria such as campylobacter jejuni, bacillus cereus, clostridium perfringens, escherichia coli, salmonella enterica, staphylococcus aureus, vibrio cholerae, and vibrio parahemolyticus can adversely affect animal and human health, but a better understanding of the factors involved in their pathogenesis is needed. to help meet this need, this overview surveys and interprets much of our current knowledge of antibiotic (multidrug)-resistant bacteria in th ...201525856120
antimicrobial activities of active component isolated from lawsonia inermis leaves and structure-activity relationships of its analogues against food-borne bacteria.the antimicrobial activities of lawsonia inermis leaf extract and 2-hydroxy-1,4-naphthoquinone analogues against food-borne bacteria. the antimicrobial activities of five fractions derived from the methanol extract of lawsonia inermis leaves were evaluated against 7 food-borne bacteria. 2-hydroxy-1,4-naphthoquinone was isolated by chromatographic analyses. 2-hydroxy-1,4-naphthoquinone showed the strong activities against bacillus cereus, listeria monocytogenes, salmonella enterica, shigella sonn ...201525829631
improved in vitro assay for determining the mucin adherence of bacteria sensitive to triton x-100 treatment.mucin-associated microbiota are in relatively close contact with the intestinal epithelium and may thus have a more pronounced effect on host health. we have previously developed a simple mucin agar assay to simulate initial mucus colonization by intestinal microbial communities. adherence of microbiota was estimated using flow cytometry after detachment with triton x-100. in this study, the effect of this detergent on the cultivability of both virulent and commensal strains was investigated. mu ...201525702162
pyrosequencing analysis of microbial community and food-borne bacteria on restaurant cutting boards collected in seri kembangan, malaysia, and their correlation with grades of food premises.this study adopts the pyrosequencing technique to identify bacteria present on 26 kitchen cutting boards collected from different grades of food premises around seri kembangan, a city in malaysia. pyrosequencing generated 452,401 of total reads of otus with an average of 1.4×10(7) bacterial cells/cm(2). proteobacteria, firmicutes and bacteroides were identified as the most abundant phyla in the samples. taxonomic richness was generally high with >1000 operational taxonomic units (otus) observed ...201525679309
antimicrobial potential of cauliflower, broccoli, and okara byproducts against foodborne bacteria.the antimicrobial potential of cauliflower, broccoli, and okara byproducts was assessed against gram-positive and gram-negative bacteria. salmonella enterica serovar typhimurium, escherichia coli o157:h7, bacillus cereus, and listeria monocytogenes serovar 4b growth behavior was assessed under exposure to 5% vegetable byproducts added to the reference medium, buffered peptone water (0.1% [wt/vol]), at 37°c. although the byproducts were not effective against l. monocytogenes, they were bactericid ...201525587927
propidium monoazide combined with real-time pcr for selective detection of viable staphylococcus aureus in milk powder and meat products.staphylococcus aureus is a spherical, gram-positive, pathogenic bacterium commonly associated with bovine mastitis and clinical infections. it is also recognized as a pathogen that causes outbreaks of food poisoning. the objective of this study was to develop and evaluate a rapid and reliable technique that combines propidium monoazide (pma) staining with real-time quantitative (q)pcr to detect and quantify viable cells of staph. aureus in milk powder and meat products. the inclusivity and exclu ...201525582587
aerobic bacterial microbiota isolated from the cloaca of the european pond turtle (emys orbicularis) in poland.we conducted a comparative analysis of the aerobic cloacal bacteria of european pond turtles (emys orbicularis) living in their natural environment and juvenile turtles reared under controlled conditions in a breeding center. we included 130 turtles in the study. the aerobic bacteria isolated from the cloaca of the juvenile turtles were less diverse and more prevalent than the bacteria isolated from free-living adults. we isolated 17 bacterial species from juvenile captive turtles, among which t ...201525380369
a novel antimicrobial peptide derived from fish goose type lysozyme disrupts the membrane of salmonella enterica.in aquaculture, accumulation of antibiotics resulted in development of resistance among bacterial pathogens. consequently, it became mandatory to find alternative to synthetic antibiotics. antimicrobial peptides (amps) which are described as evolutionary ancient weapons have been considered as promising alternates in recent years. in this study, a novel antimicrobial peptide had been derived from goose type lysozyme (lyzg) which was identified from the cdna library of freshwater fish channa stri ...201526477736
enhancement of mechanical properties, microstructure, and antimicrobial activities of zein films cross-linked using succinic anhydride, eugenol, and citric acid.zein constitutes about half of the endosperm proteins in corn. recently, attempts have been made to utilize zein for food coatings and biodegradable materials, which require better physical properties, using chemical modification of zein. in this study, zein proteins were modified using citric acid, succinic anhydride, and eugenol as natural cross-linking agents in the wet state. the cross-linkers were added either separately or combined in increment concentrations (0.1, 0.2, 0.3, and 0.4%). the ...201525036665
biological activity of the essential oils from cinnamodendron dinisii and siparuna guianensis.this study had analyzed the antibacterial, antifungal and trypanocidal activity of the essential oils from cinnamodendron dinisii schwacke (canellaceae) and siparuna guianensis aublet (siparunaceae). the essential oils were obtained from fresh leaves by hydrodistillation, using a modified clevenger apparatus. chemical analysis by gas-liquid chromatography coupled to mass spectrometry (gc-ms) showed that these essential oils are rich in monoterpene and sesquiterpene hydrocarbons. activity against ...201526221107
potential probiotic attributes of a new strain of bacillus coagulans cgmcc 9951 isolated from healthy piglet feces.a new strain of bacillus coagulans cgmcc 9551, which has a broad range of antibacterial activities against six main pathogenic bacteria including escherichia coli o8, staphylococcus aureus, salmonella enterica subsp. enterica serovar enteritidis, streptococcus suis, listeria monocytogenes and pasteurella multocida, was isolated from healthy piglet feces. in adhesion assay, the isolate exhibited a stronger adhesion to pig intestinal mucus than that of b. subtilis jt143 and l. acidophilus ly24 res ...201525752235
alternative fecal indicators and their empirical relationships with enteric viruses, salmonella enterica, and pseudomonas aeruginosa in surface waters of a tropical urban catchment.the suitability of traditional microbial indicators (i.e., escherichia coli and enterococci) has been challenged due to the lack of correlation with pathogens and evidence of possible regrowth in the natural environment. in this study, the relationships between alternative microbial indicators of potential human fecal contamination (bacteroides thetaiotaomicron, methanobrevibacter smithii, human polyomaviruses [hpyvs], and f+ and somatic coliphages) and pathogens (salmonella spp., pseudomonas ae ...201525416765
crystal structure of β-n-acetylglucosaminidase cbsa from thermotoga neapolitana.cbsa from the thermophilic marine bacteria thermotoga neapolitana is a chitinolyitc enzyme that can cleave a glycosidic bond of the polymer n-acetylglucosamine at the non-reducing end. this enzyme has particularly high activity on di-n-acetylchitobiose. cbsa consists of a family of 3 glycoside hydrolase (gh3)-type catalytic domains and a unique c-terminal domain. the c-terminal domain distinguishes cbsa from other gh3-type enzymes. sequence analyses have suggested that cbsa has the asp-his dyad ...201526187666
proteome-wide lysine acetylation profiling of the human pathogen mycobacterium tuberculosis.n(ɛ)-acetylation of lysine residues represents a pivotal post-translational modification used by both eukaryotes and prokaryotes to modulate diverse biological processes. mycobacterium tuberculosis is the causative agent of tuberculosis, one of the most formidable public health threats. many aspects of the biology of m. tuberculosis remain elusive, in particular the extent and function of n(ɛ)-lysine acetylation. with a combination of anti-acetyllysine antibody-based immunoaffinity enrichment wi ...201525456444
microbiological survey of birds of prey pellets.a microbiological survey of 73 pellets collected from different birds of prey species housed at the wildlife rescue and rehabilitation center of napoli (southern italy) was performed. pellets were analyzed by culture and biochemical methods as well as by serotyping and polymerase chain reaction. we isolated a wide range of bacteria some of them also pathogens for humans (i.e. salmonella enterica serotype typhimurium, campylobacter coli, escherichia coli o serogroups). this study highlights the p ...201526026881
tracking the elusive function of bacillus subtilis hfq.rna-binding protein hfq is a key component of the adaptive responses of many proteobacterial species including escherichia coli, salmonella enterica and vibrio cholera. in these organisms, the importance of hfq largely stems from its participation to regulatory mechanisms involving small non-coding rnas. in contrast, the function of hfq in gram-positive bacteria has remained elusive and somewhat controversial. in the present study, we have further addressed this point by comparing growth phenoty ...201525915524
near-infrared spectroscopy for the detection and quantification of bacterial contaminations in pharmaceutical products.accurate detection and quantification of microbiological contaminations remains an issue mainly due the lack of rapid and precise analytical techniques. standard methods are expensive and time-consuming being associated to high economic losses and public health threats. in the context of pharmaceutical industry, the development of fast analytical techniques able to overcome these limitations is crucial and spectroscopic techniques might constitute a reliable alternative. in this work we proved t ...201526151105
compounds in a particular production lot of tryptic soy broth inhibit staphylococcus aureus cell growth.staphylococcus aureus newman strain and several methicillin-resistant s. aureus (mrsa) clinical isolates were grown on agar plates prepared with conventional lots of tryptic soy broth (tsb). cell growth of these strains was inhibited on agar plates containing tsb of a particular product lot (lot a), whereas the cell growth of s. aureus rn4220 strain and several other mrsa clinical isolates was not inhibited. the cell growth of a strain of s. epidermidis was also inhibited on agar plates containi ...201526193939
burkholderia cenocepacia and salmonella enterica arnt proteins that transfer 4-amino-4-deoxy-l-arabinose to lipopolysaccharide share membrane topology and functional amino acids.we recently demonstrated that incorporation of 4-amino-4-deoxy-l-arabinose (l-ara4n) to the lipid a moiety of lipopolysaccharide (lps) is required for transport of lps to the outer membrane and viability of the gram-negative bacterium burkholderia cenocepacia. arnt is a membrane protein catalyzing the transfer of l-ara4n to the lps molecule at the periplasmic face of the inner membrane, but its topology and mechanism of action are not well characterized. here, we elucidate the topology of arnt a ...201526030265
flgm is secreted by the flagellar export apparatus in bacillus subtilis.the bacterial flagellum is assembled from over 20 structural components, and flagellar gene regulation is morphogenetically coupled to the assembly state by control of the anti-sigma factor flgm. in the gram-negative bacterium salmonella enterica, flgm inhibits late-class flagellar gene expression until the hook-basal body structural intermediate is completed and flgm is inhibited by secretion from the cytoplasm. here we demonstrate that flgm is also secreted in the gram-positive bacterium bacil ...201525313396
immune response of salmonella challenged broiler chickens fed diets containing gallipro®, a bacillus subtilis probiotic.this study was conducted to investigate the effect of feeding a probiotic, bacillus subtilis, on antibody titers against newcastle and infectious bursal viruses in broiler chickens challenged with salmonella enterica serotype enteritidis. one hundred and sixty 1-day-old broiler chicks were randomly assigned to four treatments in a completely randomized design. the treatments were negative control, probiotic-treated group, challenged group, and challenged probiotic treated group. salmonella chall ...201525344127
interactions of salmonella enterica subspecies enterica serovar typhimurium with gut bacteria.the aim of this study was to evaluate the impact of the gut microbiota on the growth and survival of s. typhimurium. this was tested in two-species co-cultures and in mixed cultures with a simplified gut model microbiota. subsequently, interactions between s. typhimurium and human faecal bacteria were quantified in both batch and continuous culture systems simulating the human colon. the exponential growth of s. typhimurium was halted when the population of escherichia coli reached the maximum p ...201525727571
prioritisation of wildlife pathogens to be targeted in european surveillance programmes: expert-based risk analysis focus on ruminants.this study attempted to develop a list of priority pathogens. it is part of a european union (eu) project dedicated to the surveillance of emerging or re-emerging pathogens of wildlife. partners of the consortium established an initial list of 138 pathogens of concern, which was reduced to a smaller list of 65 pathogens likely to affect ruminants (i.e., the most costly animal group in the eu over the last 15 years). these 65 pathogens underwent a two-step, expert-based risk analysis: 92 experts ...201525496774
generation and use of site-directed chromosomal cyaa' translational fusions in salmonella enterica.cyaa from bordetella pertussis is a calmodulin-dependent adenylate cyclase. fusions to the catalytic domain of cyaa (cyaa') are useful tools to detect translocation of type iii secretion system effectors from gram-negative pathogens like salmonella enterica. these fusions are usually generated using plasmids with strong promoters. here, we describe a protocol to insert the cyaa'-encoding sequence in a specific site in the bacterial chromosome in order to get a monocopy fusion whose expression is ...201525253250
mining host-pathogen protein interactions to characterize burkholderia mallei infectivity mechanisms.burkholderia pathogenicity relies on protein virulence factors to control and promote bacterial internalization, survival, and replication within eukaryotic host cells. we recently used yeast two-hybrid (y2h) screening to identify a small set of novel burkholderia proteins that were shown to attenuate disease progression in an aerosol infection animal model using the virulent burkholderia mallei atcc 23344 strain. here, we performed an extended analysis of primarily nine b. mallei virulence fact ...201525738731
a novel microbial source tracking microarray for pathogen detection and fecal source identification in environmental systems.pathogen detection and the identification of fecal contamination sources are challenging in environmental waters. factors including pathogen diversity and ubiquity of fecal indicator bacteria hamper risk assessment and remediation of contamination sources. a custom microarray targeting pathogens (viruses, bacteria, protozoa), microbial source tracking (mst) markers, and antibiotic resistance genes was tested against dna obtained from whole genome amplification (wga) of rna and dna from sewage an ...201525970344
antibiotic susceptibility and prevalence of foodborne pathogens in poultry meat in romania.the occurrence of pathogenic strains in poultry meat is of growing concern in romania. another problem found on a global level is the continuous increase of antimicrobial resistance in bacteria isolated from food. this study aimed to evaluate the prevalence of pathogenic bacteria in poultry carcasses obtained in romania in 2012-2013 and to reveal the most prevalent patterns of antimicrobial resistance in the isolated strains.201525596569
conservation and covariance in small bacterial phosphoglycosyltransferases identify the functional catalytic core.phosphoglycosyltransferases (pgts) catalyze the transfer of a c1'-phosphosugar from a soluble sugar nucleotide diphosphate to a polyprenol phosphate. these enzymes act at the membrane interface, forming the first membrane-associated intermediates in the biosynthesis of cell-surface glycans and glycoconjugates, including glycoproteins, glycolipids, and the peptidoglycan in bacteria. pgts vary greatly in both their membrane topologies and their substrate preferences. pgts, such as mray and weca, a ...201526600273
[the significance of fucosylated glycoconjugates of human milk in nutrition of newborns and infants].human milk is extremely complex secretion rich in biologically active glycoconjugates including free oligosaccharides, glycoproteins, glycolipids, and glycosaminoglycans. alpha1-2-fucosylated glycoconjugates of human milk are component of the innate immune system and provide an additional defense for infants. participation of fucosylated glycotopes in the inhibition of infections caused by some bacteria and/or viruses rely on blocking of lectin-receptors of pathogen. free fucosylated glycoconjug ...201526206995
low dietary iron intake restrains the intestinal inflammatory response and pathology of enteric infection by food-borne bacterial pathogens.orally administrated iron is suspected to increase susceptibility to enteric infections among children in infection endemic regions. here we investigated the effect of dietary iron on the pathology and local immune responses in intestinal infection models. mice were held on iron-deficient, normal iron, or high iron diets and after 2 weeks they were orally challenged with the pathogen citrobacter rodentium. microbiome analysis by pyrosequencing revealed profound iron- and infection-induced shifts ...201526046550
septic arthritis in infants younger than 3 months: a retrospective review.septic arthritis in infants is rare and can be difficult to diagnose. this study reviewed a series of patients younger than 3 months to identify factors that may assist in early diagnosis and treatment. a query of records at a large midwestern pediatric hospital (1994-2010) was performed to identify all patients younger than 3 months at the time of diagnosis. analysis included birth history, joint involvement, physical examination findings, laboratory results, imaging results, method of treatmen ...201526375536
molecular survey of occurrence and quantity of legionella spp., mycobacterium spp., pseudomonas aeruginosa and amoeba hosts in municipal drinking water storage tank sediments.to examine the occurrence and quantity of potential pathogens and an indicator of microbial contamination in the sediments of municipal drinking water storage tanks (mdwsts), given the absence of such data across the united states.201525891145
synthesis of silver nanoparticles by phoma gardeniae and in vitro evaluation of their efficacy against human disease-causing bacteria and fungi.the authors report the biological synthesis of silver nanoparticles (nps) by phoma gardeniae (itcc 4554). the detection of silver np formation was done by visual observation, and uv-vis spectrophotometer analysis. further, these mycogenic silver nps were characterised by fourier transform infrared spectroscopy (ftir), transmission electron microscopy (tem) and nanoparticle tracking and analysis system. the tem analysis revealed the formation of spherical and polydispersed nps within the range of ...201525829172
[demonstration of β-1,2 mannan structures expressed on the cell wall of candida albicans yeast form but not on the hyphal form by using monoclonal antibodies].candida albicans is a polymorphic fungus that may be observed as both commensal and opportunistic pathogen in humans. as one of the major components of candida cell wall structure, mannan plays an important role in the fungus-host cell interaction and in virulence. the ability to switch from yeast to hypha form of microorganism is crutial in the development of c.albicans infections. hyphal form has different antigenic properties compared to yeast form and structural changes occur in the yeast ce ...201525706732
crystal structure of dsba from corynebacterium diphtheriae and its functional implications for cuep in gram-positive bacteria.in gram-negative bacteria in the periplasmic space, the dimeric thioredoxin-fold protein dsbc isomerizes and reduces incorrect disulfide bonds of unfolded proteins, while the monomeric thioredoxin-fold protein dsba introduces disulfide bonds in folding proteins. in the gram-negative bacteria salmonella enterica serovar typhimurium, the reduced form of cuep scavenges the production of hydroxyl radicals in the copper-mediated fenton reaction, and dsbc is responsible for keeping cuep in the reduced ...201526082031
rab antibody characterization: comparison of rab14 antibodies.rab14 functions in the endocytic recycling pathway, having been implicated in the trafficking of the adam10 protease, glut4, and components of cell-cell junctions to the plasma membrane. it localizes predominantly to endocytic membranes with a pool also found on trans-golgi network (tgn) membranes, and is most closely related to the rab11 subfamily of gtpases. certain intracellular bacteria such as legionella pneumophila, chlamydia trachomatis, and salmonella enterica utilize rab14 to promote th ...201525800840
comparison of desiccation tolerance among listeria monocytogenes, escherichia coli o157:h7, salmonella enterica, and cronobacter sakazakii in powdered infant formula.bacterial pathogens such as listeria monocytogenes, escherichia coli o157:h7, salmonella enterica, and cronobacter sakazakii have demonstrated long-term survival in/on dry or low-water activity (aw) foods. however, there have been few comparative studies on the desiccation tolerance among these bacterial pathogens separately in a same food matrix. in the present study, the survival kinetics of the four bacterial pathogens separately inoculated onto powdered infant formula as a model low-aw food ...201525581184
selection for pro-inflammatory mediators produces chickens more resistant to eimeria tenella.we recently developed a novel selection method based on identification and selection of chickens with an inherently high and low phenotype of pro-inflammatory mediators, including interleukin (il)-6, cxcli2, and ccli2. the resultant high line of chickens is more resistant to salmonella enterica serovar enteritidis (salmonella enteritidis) compared to the low line. in the current study, we sought to determine if the high line birds were also more resistant to the protozoan parasite eimeria tenell ...201525577794
effects of listeria monocytogenes egd-e and salmonella enterica ser. typhimurium lt2 chitinases on intracellular survival in dictyostelium discoideum and mammalian cell lines.some bacterial pathogens produce chitinases as virulence factors during host infection. the molecular target of such enzymes in non-chitinous hosts remains uncertain. we studied the importance of listeria monocytogenes egd-e and salmonella enterica ser. typhimurium lt2 chitinases for intracellular survival in dictyostelium discoideum, and for salmonella, also infection of mammalian cell lines, and a mouse model. the salmonella chitinase did not contribute significantly to infection of d. discoid ...201525908871
the question of pathogen quantification in disinfected graywater.graywater (gw) reuse for irrigation is recognized as a sustainable solution for water conservation. one of the major impediments to gw reuse is the presence of pathogenic microorganisms. this study monitored three similar on-site gw treatment systems bi-monthly over the course of a year to compare the presence of pathogens and indicators in raw, biologically treated, and biologically treated and disinfected [by chlorine and ultraviolet light (uv)] gw. the systems were designed to allow the testi ...201525437766
intraepithelial lymphocyte numbers and histomorphological parameters in the porcine gut after enterococcus faecium ncimb 10415 feeding in a salmonella typhimurium challenge.salmonellae are among the most widespread sources of foodborne infections and salmonella typhimurium, in particular, is correlated with human disease caused by the consumption of contaminated pork. intraepithelial lymphocytes (iel) have early contact with intestinal antigens and play an important role in the detection of pathogenic bacteria. the objective of this study was to determine whether a presumed probiotic enterococcus faecium strain could improve histomorphological and immune system-rel ...201525669594
cross-reactivity of rapid salmonella typhi igm immunoassay in dengue fever without co-existing infection.dengue fever is endemic in developing nations worldwide with as many as 500,000 annual cases of dengue hemorrhagic fever (dhf) and dengue shock syndrome (dss). a prompt and accurate diagnosis early in the disease course is essential for prompt identification and treatment of severe complications of the dengue virus infection (dvi). we identified cross-reactivity of a rapid igm test for typhoid fever in patients with febrile illnesses that were determined to be due to dengue virus.201526798572
characterization of lactobacillus fermentum pl9988 isolated from healthy elderly korean in a longevity village.in this work, we wanted to develop a probiotic from famous longevity villages in korea. we visited eight longevity villages in korea to collect fecal samples from healthy adults who were aged above 80 years and had regular bowel movements, and isolated lactic-acid-producing bacteria from the samples. isolated colonies that appeared on mrs agar containing bromophenol blue were identified by means of 16s rrna sequencing, and 102 of the isolates were identified as lactic-acid-producing bacteria (18 ...201526095384
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