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fluoroquinolone resistance in salmonella enterica serotype choleraesuis, taiwan, 2000-2003.salmonella enterica serotype choleraesuis is a highly invasive pathogen that infects humans and causes systemic infections that require antimicrobial therapy. surveillance in taiwan showed that fluoroquinolone resistance in s. choleraesuis markedly increased from 2000 to 2003, reaching approximately 70% in 2003.200415498176
the salmonella membrane protein igaa modulates the activity of the rcsc-yojn-rcsb and phop-phoq regulons.the salmonella enterica serovar typhimurium membrane protein igaa and the phop-phoq two-component system are used by this pathogen to attenuate the intracellular growth rate within fibroblasts. igaa has also recently been shown to contribute to virulence by exerting tight repression of the rcsc-yojn-rcsb phosphorelay in host tissues. here we show that loss of repression of the rcsc-yojn-rcsb system, linked to an r188h mutation in the igaa protein (igaa1 allele), is accompanied by altered express ...200415516559
lack of yggx results in chronic oxidative stress and uncovers subtle defects in fe-s cluster metabolism in salmonella enterica.as components involved in fe-s cluster metabolism are described, the challenge becomes defining the integrated process that occurs in vivo based on the individual functions characterized in vitro. strains lacking yggx have been used here to mimic chronic oxidative stress and uncover subtle defects in fe-s cluster metabolism. we describe the in vivo similarities and differences between isc mutants, which have a known function in cluster assembly, and mutants disrupted in four additional loci, gsh ...200415516576
evidence that a b12-adenosyl transferase is encoded within the ethanolamine operon of salmonella enterica.adenosylcobalamin (ado-b12) is both the cofactor and inducer of ethanolamine ammonia lyase (ea-lyase), a catabolic enzyme for ethanolamine. de novo synthesis of ado-b12 by salmonella enterica occurs only under anaerobic conditions. therefore, aerobic growth on ethanolamine requires import of ado-b12 or a precursor (cn-b12 or oh-b12) that can be adenosylated internally. several known enzymes adenosylate corrinoids. the coba enzyme transfers adenosine from atp to a biosynthetic intermediate in de ...200415516577
the cora mg2+ transporter does not transport fe2+.cora encodes the constitutively expressed primary mg2+ uptake system of most eubacteria and many archaea. recently, a mutation in cora was reported to make salmonella enterica serovar typhimurium markedly resistant to fe2+-mediated toxicity. mechanistically, this was hypothesized to be from an ability of cora to mediate the influx of fe2+. consequently, we directly examined fe2+ transport and toxicity in wild-type versus cora cells. as determined by direct transport assay, cora cannot transport ...200415516579
the complete nucleotide sequence of the resistance plasmid r478: defining the backbone components of incompatibility group h conjugative plasmids through comparative genomics.horizontal transfer of resistance determinants amongst bacteria can be achieved by conjugative plasmid dna elements. we have determined the complete 274,762 bp sequence of the incompatibility group h (inch) plasmid r478, originally isolated from the gram negative opportunistic pathogen serratia marcescens. this self-transferable extrachromosomal genetic element contains 295 predicted genes, of which 144 are highly similar to coding sequences of inch plasmids r27 and phcm1. the regions of similar ...200415518875
sequence analysis and characterization of sulfonamide resistance plasmid prf-1 from salmonella enterica serovar choleraesuis.the nucleotide sequence of a small plasmid, designated prf-1, isolated from salmonella enterica serovar choleraesuis, was determined. we identified seven open reading frames (orfs) encoded by 6066 nucleotides with a total g + c content of 53.6%. analysis of the complete nucleotide sequence revealed a replicon of prf-1 to have high similarity to the p15a origin of replication, with a possible cer-like region. orf1, which is composed of 816 nucleotides, shows a high degree of similarity to dihydro ...200415518878
identification of host-specific colonization factors of salmonella enterica serovar typhimurium.the severity of infections caused by salmonella enterica serovar typhimurium varies depending on the host species. numerous virulence genes have been identified in s. typhimurium, largely from studies in mice, but their roles in infections of other species remain unclear. in the most comprehensive survey of its kind, through the use of signature-tagged mutagenesis of s. typhimurium we have identified mutants that were unable to colonize calf intestines, mutants unable to colonize chick intestine ...200415522082
growth inhibition of foodborne pathogens and food spoilage organisms by select raw honeys.twenty-seven honey samples from different floral sources and geographical locations were evaluated for their ability to inhibit the growth of seven food spoilage organisms (alcaligenes faecalis, aspergillus niger, bacillus stearothermophilus, geotrichum candidum, lactobacillus acidophilus, penicillium expansum, pseudomonas fluorescens) and five foodborne pathogens (bacillus cereus, escherichia coli o157:h7, listeria monocytogenes, salmonella enterica ser. typhimurium, and staphylococcus aureus) ...200415527912
2-methylcitrate-dependent activation of the propionate catabolic operon (prpbcde) of salmonella enterica by the prpr protein.the function of the prpr protein of salmonella enterica serovar typhimurium lt2 was studied in vitro and in vivo. the prpr protein is a sensor of 2-methylcitrate (2-mc), an intermediate of the 2-methylcitric acid cycle used by this bacterium to convert propionate to pyruvate. prpr was unresponsive to citrate (a close structural analogue of 2-mc) and to propionate, suggesting that 2-mc, not propionate, is the metabolite that signals the presence of propionate in the environment to s. enterica. pr ...200415528672
descriptive study of california egg layer premises and analysis of risk factors for salmonella enterica serotype enteritidis as characterized by manure drag swabs.this cross-sectional, double-blind study reports the prevalence of salmonella enterica serotype enteritidis (se) on california egg layer premises using single vs. pooled manure drag swabs and presents a description of egg production and management systems in the state and an initial analysis of risk factors for se. the study included 91% of all known eligible egg premises in california, representing the majority of eggs produced in the state. the overall prevalence of se on california egg layer ...200415529977
comparison of genome degradation in paratyphi a and typhi, human-restricted serovars of salmonella enterica that cause typhoid.salmonella enterica serovars often have a broad host range, and some cause both gastrointestinal and systemic disease. but the serovars paratyphi a and typhi are restricted to humans and cause only systemic disease. it has been estimated that typhi arose in the last few thousand years. the sequence and microarray analysis of the paratyphi a genome indicates that it is similar to the typhi genome but suggests that it has a more recent evolutionary origin. both genomes have independently accumulat ...200415531882
cell tropism of salmonella enterica.salmonella serotypes are able to actively cross the intestinal epithelium, mainly but not exclusively through m cells in the follicle-associated epithelium of peyer's patches. once reaching the basal side of the epithelium, salmonella serotypes are internalized by macrophages, dendritic cells, and neutrophils but are not found in fibroblasts or other mesenchymal cells. the outcome of the interaction between salmonella serotypes and dendritic cells or neutrophils is detrimental to the pathogen. i ...200415532980
expression profiles of effector proteins sopb, sopd1, sope1, and avra differ with systemic, enteric, and epidemic strains of salmonella enterica.the presence and expression of sopb, sopd1, sope1, and avra genes encoding virulence associated effector proteins were studied comparatively in 405 salmonella enterica strains. they belong to different serovars and clonal types (genotypes, phage types) and originated from different clinical (systemic infection, focal enteritis, enterocolitis) and epidemic sources (epidemics, sporadic cases). the sopb and sopd1 determinants were commonly prevalent, but sope1 and avra genes only in 55% and 80%, re ...200415538712
molecular and epidemiologic analysis of a county-wide outbreak caused by salmonella enterica subsp. enterica serovar enteritidis traced to a bakery.an increase in the number of attendees due to acute gastroenteritis and fever was noted at one hospital emergency room in taiwan over a seven-day period from july to august, 2001. molecular and epidemiological surveys were performed to trace the possible source of infection.200415541186
improved efficiency of a salmonella-based vaccine against human papillomavirus type 16 virus-like particles achieved by using a codon-optimized version of l1.cervical cancer results from cervical infection by human papillomaviruses (hpvs), especially hpv16. an effective vaccine against these hpvs is expected to have a dramatic impact on the incidence of this cancer and its precursor lesions. the leading candidate, a subunit prophylactic hpv virus-like particle (vlp) vaccine, can protect women from hpv infection. an alternative improved vaccine that avoids parenteral injection, that is efficient with a single dose, and that induces mucosal immunity mi ...200415542642
[interaction of neomycin with other antibiotics on selected bacterial strains].antimicrobial combinations are used most frequently to provide broad-spectrum empirical coverage in the treatment of bacterial infections. however, combination of two antibiotics may not influence their activity, may lead to synergy or antagonism in the activity. neomycin may be combined with one of the following antibiotics: ampicillin, procaine penicillin, gramicidin, bacitracin, polymyxin b, lincomycin, oxytetracycline, and erythromycin in some human and veterinary multiantibiotic drugs distr ...200415544091
direct detection of bacterial pathogens in representative dairy products using a combined bacterial concentration-pcr approach.to develop a simple, rapid method to concentrate and purify bacteria and their nucleic acids from complex dairy food matrices in preparation for direct pathogen detection using polymerase chain reaction (pcr).200415546401
purification and initial characterization of the salmonella enterica pduo atp:cob(i)alamin adenosyltransferase.the pduo enzyme of salmonella enterica is an atp:cob(i)alamin adenosyltransferase that catalyzes the final step in the conversion of vitamin b(12) to coenzyme b(12). the primary physiological role of this enzyme is to support coenzyme b(12)-dependent 1,2-propanediol degradation, and bioinformatic analysis has indicated that it has two domains. here the pduo adenosyltransferase was produced in escherichia coli, solubilized from inclusion bodies, purified to apparent homogeneity, and partially cha ...200415547259
transferable antibiotic resistance elements in haemophilus influenzae share a common evolutionary origin with a diverse family of syntenic genomic islands.transferable antibiotic resistance in haemophilus influenzae was first detected in the early 1970s. after this, resistance spread rapidly worldwide and was shown to be transferred by a large 40- to 60-kb conjugative element. bioinformatics analysis of the complete sequence of a typical h. influenzae conjugative resistance element, icehin1056, revealed the shared evolutionary origin of this element. icehin1056 has homology to 20 contiguous sequences in the national center for biotechnology inform ...200415547285
environmental surveillance for salmonella enterica in a veterinary teaching hospital.to evaluate the extent of environmental contamination with salmonella enterica in a veterinary teaching hospital.200415552306
antibacterial effect of water-soluble tea extracts on foodborne pathogens in laboratory medium and in a food model.the microbial inhibition of foodborne pathogens was determined in brain heart infusion broth with 10% (wt/vol) water-soluble extracts of green, jasmine, black, dungglre, and oolong tea against escherichia coli o157:h7, salmonella enterica serovar enteritidis, listeria monocytogenes, and staphylococcus aureus. the mixed culture (approximately 6.0 log cfu/ml), which was composed of the four pathogens, was inoculated into brain heart infusion broth with and without tea extracts. after incubation at ...200415553649
the related effector proteins sopd and sopd2 from salmonella enterica serovar typhimurium contribute to virulence during systemic infection of mice.salmonella resides within host cells in a vacuole that it modifies through the action of virulence proteins called effectors. here we examined the role of two related effectors, sopd and sopd2, in salmonella pathogenesis. salmonella enterica serovar typhimurium (s. typhimurium) mutants lacking either sopd or sopd2 were attenuated for replication in the spleens of infected mice when competed against wild-type bacteria in mixed infection experiments. a double mutant lacking both effector genes did ...200415554961
salmonella carrier state in chicken: comparison of expression of immune response genes between susceptible and resistant animals.asymptomatic salmonella enterica serovar enteritidis carrier state in poultry has serious consequences on food safety and public health due to the risks of food poisoning following consumption of contaminated products. an understanding the mechanisms of persistence of salmonella in the digestive tract of chicken can be achieved by a better knowledge of the defects in the control of infection in susceptible versus resistant animals. the gene expression of innate immune response factors including ...200415555534
salmonella enterica serovar typhimurium infection induces cyclooxygenase 2 expression in macrophages: involvement of salmonella pathogenicity island 2.salmonella pathogenicity island 2 (spi-2) is required for intramacrophage survival and systemic infection in mice. we have recently reported that salmonella enterica causes activation of the protein kinase a (pka) signaling pathway in a manner dependent on spi-2, resulting in the upregulation of interleukin-10 expression in macrophages (k. uchiya et al., infect. immun. 72:1964-1973, 2004). we show in the present study the involvement of spi-2 in a signal transduction pathway that induces the exp ...200415557607
induction of cationic chicken liver-expressed antimicrobial peptide 2 in response to salmonella enterica infection.cationic antimicrobial peptides constitute part of the innate immune system and provide an essential role in the defense against infection. at present there is a paucity of information regarding the antimicrobial profile of the chicken (gallus gallus). using in silico studies, an expressed sequence tag (est) clone was identified which encodes a novel cationic antimicrobial peptide, chicken liver-expressed antimicrobial peptide 2 (cleap-2). the predicted amino acid sequence composed a prepropepti ...200415557621
oral vaccination of balb/c mice with salmonella enterica serovar typhimurium expressing pseudomonas aeruginosa o antigen promotes increased survival in an acute fatal pneumonia model.pseudomonas aeruginosa is a leading cause of nosocomial pneumonia. we compared the efficacies of oral and intraperitoneal (i.p.) vaccinations of balb/c mice with attenuated salmonella enterica serovar typhimurium sl3261 expressing p. aeruginosa serogroup o11 o antigen to protect against p. aeruginosa infection in an acute fatal pneumonia model. oral and i.p. vaccines elicited o11-specific serum immunoglobulin g (igg) antibodies, but iga was observed only after oral immunization. challenge of ora ...200415557624
adaptation of the endogenous salmonella enterica serovar typhi clya-encoded hemolysin for antigen export enhances the immunogenicity of anthrax protective antigen domain 4 expressed by the attenuated live-vector vaccine strain cvd 908-htra.bacterial live-vector vaccines aim to deliver foreign antigens to the immune system and induce protective immune responses, and surface-expressed or secreted antigens are generally more immunogenic than cytoplasmic constructs. we hypothesize that an optimum expression system will use an endogenous export system to avoid the need for large amounts of heterologous dna encoding additional proteins. here we describe the cryptic chromosomally encoded 34-kda cytolysin a hemolysin of salmonella enteric ...200415557633
synovial fibroblasts infected with salmonella enterica serovar typhimurium mediate osteoclast differentiation and activation.the mechanisms whereby arthritogenic organisms may induce cartilage and bone erosions in infection-triggered arthritis remain unknown. in this study, we asked whether an arthritogenic organism could contribute to osteoclast differentiation and activation through regulation of the receptor activator of nf-kappab ligand (rankl) in synovial fibroblasts. rat synovial fibroblasts were infected in vitro with salmonella enterica serovar typhimurium and monitored over time. the expression of rankl in re ...200415557643
pigeon-associated strains of salmonella enterica serovar typhimurium phage type dt2 have genomic rearrangements at rrna operons.strains from a subgroup of salmonella enterica serovar typhimurium frequently associated with pigeon infections were tested for genomic anomalies and virulence in mice. some strains have a genomic inversion between rrn operons. two prophages found in the common laboratory strain lt2 were absent. pigeon-associated strains are still virulent in mice.200415557664
effect of inactivation of the htra-like serine protease degq on the virulence of salmonella enterica serovar typhimurium in mice.degq is a serine protease that is highly homologous to htra, an important virulence determinant of salmonella enterica serovar typhimurium. we examined if degq is involved in serovar typhimurium pathogenesis. a serovar typhimurium degq mutant was as virulent as the wild-type strain in mice. however, a serovar typhimurium htra degq mutant survived less well in murine organs, particularly in the liver, than a serovar typhimurium htra mutant. degq is not essential for serovar typhimurium pathogenes ...200415557668
cellular microbiology of intracellular salmonella enterica: functions of the type iii secretion system encoded by salmonella pathogenicity island 2.the facultative intracellular pathogen salmonella enterica resides in a special membrane compartment of the host cell and modifies its host to achieve intracellular survival and proliferation. the type iii secretion system encoded by salmonella pathogenicity island 2 (spi2) has a central role in the interference of intracellular salmonella with host cell functions. spi2 function affects antimicrobial defense mechanisms of the host, intracellular transport processes, integrity and function of the ...200415558211
a foodborne outbreak of salmonella enterica subsp. enterica serovar madelia at a silver anniversary reception.reported here is an outbreak of salmonella enterica subsp. enterica serovar madelia infection that occurred among 44 persons attending a silver anniversary reception in hesse, germany. isolates of salmonella madelia are extremely unusual, and no outbreaks associated with this serotype have been reported previously. forty-two attendees were interviewed and information was obtained from each of them regarding demographic and clinical characteristics and food consumed at the reception. twenty-four ...200415558342
suboptimal clinical response to ciprofloxacin in patients with enteric fever due to salmonella spp. with reduced fluoroquinolone susceptibility: a case series.salmonella spp. with reduced susceptibility to fluoroquinolones have higher than usual mics to these agents but are still considered "susceptible" by nccls criteria. delayed treatment response to fluoroquinolones has been noted, especially in cases of enteric fever due to such strains. we reviewed the ciprofloxacin susceptibility and clinical outcome of our recent enteric fever cases.200415380025
dual effects of mls antibiotics: transcriptional modulation and interactions on the ribosome.the macrolide-lincosamide-streptogramin (mls) antibiotics are an important group of translation inhibitors that act on the 50s ribosome. we show that, at subinhibitory concentrations, members of the mls group modulate specific groups of bacterial promoters, as detected by screening a library of promoter-luxcdabe reporter clones of salmonella enterica serovar typhimurium. the patterns of transcription permit identification of classes of promoters having differential responses to antibiotics of re ...200415380191
detection of integrons and antibiotic-resistance genes in salmonella enterica serovar typhimurium isolates with resistance to ampicillin and variable susceptibility to amoxicillin-clavulanate.we characterized 29 antimicrobial-resistant salmonella enterica serovar typhimurium strains, including four belonging to the monophasic variant 4,5,12:i:-, mostly isolated from infants. they were selected from 3230 strains isolated in the years 1990-2001 on the basis of resistance to ampicillin and variable susceptibility to the amoxicillin-clavulanate combination. twenty-three strains were resistant to more than four antibiotics. all the strains carried the bla(tem) gene and most were able to t ...200415380256
phage types, ribotypes and tetracycline resistance genes of salmonella enterica subsp. enterica serovar typhimurium strains isolated from different origins in italy.the tetracycline resistance (tet) gene patterns of 52 tetracycline resistant salmonella enterica subsp. enterica (s.) serovar typhimurium isolates collected from animals, food of animal origin, and humans in italy, were investigated to evaluate whether the tet gene patterns could be used for strain differentiation in addition to phage typing and ribotyping. the detection of tet genes was performed by specific pcr assays. ribotyping was performed automatically using pvuii as restriction enzyme. t ...200415381268
photochemical treatment of platelet concentrates with amotosalen and long-wavelength ultraviolet light inactivates a broad spectrum of pathogenic bacteria.bacterial contamination of platelet (plt) concentrates can result in transfusion-transmitted sepsis. a photochemical treatment (pct) process with amotosalen hcl and long-wavelength ultraviolet light (uva), which cross-links nucleic acids, was developed to inactivate bacteria and other pathogens in plt concentrates.200415383024
the modified wobble nucleoside uridine-5-oxyacetic acid in trnapro(cmo5ugg) promotes reading of all four proline codons in vivo.in salmonella enterica serovar typhimurium five of the eight family codon boxes are decoded by a trna having the modified nucleoside uridine-5-oxyacetic acid (cmo5u) as a wobble nucleoside present in position 34 of the trna. in the proline family codon box, one (trnaprocmo5ugg) of the three trnas that reads the four proline codons has cmo5u34. according to theoretical predictions and several results obtained in vitro, cmo5u34 should base pair with a, g, and u in the third position of the codon b ...200415383682
identification and characterization of class 1 integron resistance gene cassettes among salmonella strains isolated from healthy humans in china.twenty-three strains of salmonella spp. isolated from healthy humans in guangdong, china, were examined for their susceptibility to ten common antibiotics and the presence of antibiotic resistance integrons. all the strains were resistant to at least one antibiotic, and 4 strains were positive for the inti1 gene. polymerase chain reaction using in-f and in-b primers showed the existence of amplicons of 1,009 bp in two, 1,664 bp in one, and 1,009 bp and 1,664 bp in one of the inti1 -positive isol ...200415383699
structural organization of the pfra virulence-associated plasmid of rhamnose-positive yersinia pestis.the 137,036-bp plasmid pg8786 from rhamnose-positive yersinia pestis g8786 isolated from the high mountainous caucasian plague focus in georgia is an enlarged form of the pfra virulence-associated plasmid containing genes for synthesis of the antigen fraction 1 and phospholipase d. in addition to the completely conserved genes of the pfra backbone, pg8786 contains two large regions consisting of 4,642 and 32,617 bp, designated regions 1 and 2, respectively. region 1 retains a larger part of salm ...200415385458
role of b7 costimulatory molecules in mediating systemic and mucosal antibody responses to attenuated salmonella enterica serovar typhimurium and its cloned antigen.the purpose of the present study was to evaluate the ability of an attenuated salmonella enterica serovar typhimurium vaccine strain to up-regulate b7-1 and b7-2 on antigen-presenting cells and to examine the functional roles these costimulatory molecules play in mediating immune responses to salmonella and to an expressed cloned antigen, the saliva-binding region (sbr) of antigen i/ii. in vitro stimulation of b cells (b220+), macrophages (cd11b+), and dendritic cells (cd11c+) with s. enterica s ...200415385483
repression of the rcsc-yojn-rcsb phosphorelay by the igaa protein is a requisite for salmonella virulence.bacterial pathogenesis relies on regulators that activate virulence genes. some of them act, in addition, as repressors of specific genes. intracellular-growth-attenuator-a (igaa) is a salmonella enterica membrane protein that prevents overactivation of the rcsc-yojn-rcsb regulatory system. this negative control is critical for growth because disruption of the igaa gene is only possible in rcsc, yojn or rcsb strains. in this work, we examined the contribution of this regulatory circuit to virule ...200415387821
acrab-tolc directs efflux-mediated multidrug resistance in salmonella enterica serovar typhimurium dt104.multidrug-resistant salmonella enterica serovar typhimurium definitive phage type 104 (dt104) strains harbor a genomic island, called salmonella genomic island 1 (sgi1), which contains an antibiotic resistance gene cluster conferring resistance to ampicillin, chloramphenicol, florfenicol, streptomycin, sulfonamides, and tetracyclines. they may be additionally resistant to quinolones. among the antibiotic resistance genes there are two, i.e., flor and tet(g), which code for efflux pumps of the ma ...200415388427
increasing prevalence of quinolone resistance in human nontyphoid salmonella enterica isolates obtained in spain from 1981 to 2003.from january 1981 to december 2003, susceptibility to nalidixic acid was tested in 10,504 nontyphoid salmonella enterica isolates from patients with acute enteric disease in gipuzkoa, spain. the prevalence of nalidixic acid resistance steadily increased from less than 0.5% before 1991 to 38.5% in 2003, mainly due to the increase in resistance among isolates of the most prevalent serovar, s. enterica serovar enteritidis. for nalidixic acid-resistant isolates, the ciprofloxacin mic was eightfold h ...200415388435
variant salmonella genomic island 1 antibiotic resistance gene cluster containing a novel 3'-n-aminoglycoside acetyltransferase gene cassette, aac(3)-id, in salmonella enterica serovar newport.salmonella genomic island 1 (sgi1) harbors an antibiotic resistance gene cluster and was previously identified in the multidrug-resistant salmonella enterica serovars typhimurium dt104, agona, paratyphi b, and albany. this antibiotic resistance gene cluster is a complex class 1 integron and most often confers resistance to ampicillin (ap), chloramphenicol (cm)/florfenicol (ff), streptomycin (sm)/spectinomycin (sp), sulfonamides (su), and tetracycline (tc) (apcmffsmspsutc profile). recently, vari ...200415388438
fusidic acid-resistant mutants of salmonella enterica serovar typhimurium have low levels of heme and a reduced rate of respiration and are sensitive to oxidative stress.mutations in the translation elongation factor g (ef-g) make salmonella enterica serovar typhimurium resistant to the antibiotic fusidic acid. fus(r) mutants are hypersensitive to oxidative stress and rapidly lose viability in the presence of hydrogen peroxide. we show that this phenotype is associated with reduced activity of two catalase enzymes, hpi (a bifunctional catalase-hydroperoxidase) and hpii (a monofunctional catalase). these catalases require the iron-binding cofactor heme for their ...200415388448
prevalence of mutations within the quinolone resistance-determining region of gyra, gyrb, parc, and pare and association with antibiotic resistance in quinolone-resistant salmonella enterica.salmonella enterica isolates (n = 182) were examined for mutations in the quinolone resistance-determining region of gyra, gyrb, parc, and pare. the frequency, location, and type of gyra substitution varied with the serovar. mutations were found in parc that encoded thr57-ser, thr66-ile, and ser80-arg substitutions. mutations in the gyrb quinolone resistance-determining region were located at codon tyr420-cys or arg437-leu. novel mutations were also found in pare encoding glu453-gly, his461-tyr, ...200415388468
international dissemination of antibiotic resistant strains of bacterial pathogens.the increasing incidence of methicillin and multiple resistant staphylococcus aureus (mrsa) in nosocomial infections is mainly associated with a wide, international dissemination of well defined clonal lineages (epidemic mrsa) which are clearly different from community acquired mrsa by molecular typing patterns and structure of the staphylococcal cassette chromosome containing the meca gene. although belonging to a definite subpopulation within the species enterococcus faecium, hospital associat ...200415450197
chemotaxis in vibrio cholerae.the ability of motile bacteria to swim toward or away from specific environmental stimuli, such as nutrients, oxygen, or light provides cells with a survival advantage, especially under nutrient-limiting conditions. this behavior, called chemotaxis, is mediated by the bacteria changing direction by briefly reversing the direction of rotation of the flagellar motors. a sophisticated signal transduction system, consisting of signal transducer proteins, a histidine kinase, a response regulator, a c ...200415451094
analysis of integrons in human isolates of salmonella enterica serovar typhimurium isolated in the slovak republic.about 110 sporadic, epidemiologically unrelated salmonella enterica serovar typhimurium strains isolated in the slovak republic were analyzed for the presence of integrons. of these 110 examined strains, 47 were of definitive phage type dt104 and 63 were strains of various phage type, rdnc and untypeable, designated here as non-dt104 strains. all isolates were also tested for antimicrobial resistance to 10 antibiotics as well as for the presence of virulence plasmid. of 63 non-dt104 strains, 15 ...200415451097
effect of thermoultrasonication on salmonella enterica serovar enteritidis in distilled water and intact shell eggs.the combined effects of simultaneous application of ultrasonic waves and heat treatment (thermoultrasonication) on the survival of a strain of salmonella enterica enteritidis was studied in both distilled water and intentionally contaminated intact eggs immersed in water. although minor differences were observed between parameters obtained for thermoultrasonic treatment of bacteria suspended in water and those attached to the shell egg, the thermoultrasonication effects were considered to be of ...200415453578
experimental use of 2-nitropropanol for reduction of salmonella typhimurium in the ceca of broiler chicks.the effect of 2-nitropropanol (2npoh) administration on salmonella enterica serovar typhimurium in experimentally infected chicks was determined. chicks orally challenged with 10(6) cfu/ml of a novobiocin- and naladixic acid-resistant salmonella typhimurium at 6 days of age were divided into three groups receiving 0 (control), 6.5, and 13 mg 2npoh per bird (experiment 1) or four groups receiving 0 (control), 13, 65, and 130 mg 2npoh per bird (experiment 2). treatments were administered orally 1 ...200415453586
antibacterial effect of water-soluble arrowroot (puerariae radix) tea extracts on foodborne pathogens in ground beef and mushroom soup.antimicrobial activity of water-soluble arrowroot tea extract was evaluated against escherichia coli o157:h7, salmonella enterica serotype enteritidis, listeria monocytogenes, and staphylococcus aureus in ground beef and mushroom soup. the concentrations of arrowroot tea used were 0, 3, and 6% (wt/wt) for ground beef and 0, 1, 5, and 10% (wt/vol) for mushroom soup. samples without tea extract were considered controls. each sample was stored for 0, 1, 3, 5, and 7 days at 7 degrees c for ground be ...200415453588
intraspecies variability in the dose-response relationship for salmonella enteritidis associated with genetic differences in cellular immune response.to evaluate the effects of differences in host cellular immunity, we studied the dose-response relationship for infection with salmonella enterica serovar enteritidis (se) in two different rat strains, skewed towards t helper 1 (th1, lewis rats) or t helper 2 (th2, brown norway rats) immunoregulation. rats were exposed orally to different doses of se after overnight starvation and neutralization of gastric acid. animals were observed for clinical signs of disease, fecal excretion and se load in ...200415453596
role of the ggdef protein family in salmonella cellulose biosynthesis and biofilm formation.salmonella enterica serovar typhimurium is capable of producing cellulose as the main exopolysaccharide compound of the biofilm matrix. it has been shown for gluconacetobacter xylinum that cellulose biosynthesis is allosterically regulated by bis-(3',5') cyclic diguanylic acid, whose synthesis/degradation depends on diguanylate cyclase/phosphodiesterase enzymatic activities. a protein domain, named ggdef, is present in all diguanylate cyclase/phosphodiesterase enzymes that have been studied to d ...200415458421
crystal structure of an aminoimidazole riboside kinase from salmonella enterica: implications for the evolution of the ribokinase superfamily.the crystal structures of a salmonella enterica aminoimidazole riboside (airs) kinase, its complex with the substrate airs, and its complex with airs and an atp analog were determined at 2.6 angstroms, 2.9 angstroms, and 2.7 angstroms, respectively. the product of the salmonella-specific gene stm4066, airs kinase, is a homodimer with one active site per monomer. the core structure, consisting of an eight-stranded beta sheet flanked by eight alpha helices, indicates that airs kinase is a member o ...200415458630
[contribution of phage typing and ribotyping in investigating a typhoid fever outbreak in tunisia].a study was carried out to investigate an outbreak of typhoid fever that occurred in sousse city and in the vicinity of sousse (tunisia) during summer 1999. twenty four isolates of salmonella enterica serotype typhi were isolated in hospitalized patients with a typhoid fever in two hospitals (farhat hached sousse and m'saken) and were studied with the help of two molecular typing methods: phage typing and automated ribotyping. twenty one isolates with the vi antigen had profile dvs (degraded vi ...200415462196
antimicrobial drug resistance in nontyphoid human salmonella in belgium: trends for the period 2000-2002.in order to assess antimicrobial resistance in nontyphoid human salmonella in belgium, the six most important serovars, representing together more than 90% of laboratory confirmed cases, were randomly sampled. from june 2000 until december 2002, a total of 1756 isolates were screened for their antimicrobial resistance profile by the disc diffusion method. s. hadar strains showed the highest level of antimicrobial resistance. simultaneous resistance to ampicillin, nalidixic acid, tetracycline and ...200415462512
a ph-sensitive function and phenotype: evidence that euth facilitates diffusion of uncharged ethanolamine in salmonella enterica.the euth gene is part of an operon that allows salmonella enterica to use ethanolamine as a sole source of nitrogen, carbon, and energy. although the sequence of euth suggests a role in transport, euth mutants use ethanolamine normally under standard conditions (ph 7.0). these mutants fail to use ethanolamine at a low ph. evidence is presented that protonated ethanolamine (eth0) does not enter cells, while uncharged ethanolamine (eth0) diffuses freely across the membrane. the external concentrat ...200415466042
detection of low levels of listeria monocytogenes cells by using a fiber-optic immunosensor.biosensor technology has a great potential to meet the need for sensitive and nearly real-time microbial detection from foods. an antibody-based fiber-optic biosensor to detect low levels of listeria monocytogenes cells following an enrichment step was developed. the principle of the sensor is a sandwich immunoassay where a rabbit polyclonal antibody was first immobilized on polystyrene fiber waveguides through a biotin-streptavidin reaction to capture listeria cells on the fiber. capture of cel ...200415466560
endostatin gene therapy delivered by salmonella choleraesuis in murine tumor models.some anaerobic and facultatively anaerobic bacteria have been used experimentally as anticancer agents because of their selective growth in tumors. in this study, we exploited attenuated salmonella choleraesuis as a tumoricidal agent and a vector to deliver the endostatin gene for tumor-targeted gene therapy.200415468191
salmonella-induced macrophage death: multiple mechanisms, different outcomes.the facultative intracellular pathogen salmonella enterica triggers programmed cell death in macrophages. the close examination of this phenomenon has revealed an unusually complex picture involving diverse mechanisms that lead to different types of programmed cell death. it appears that the outcome of the interaction of salmonella with macrophages depends on the relative contribution of two type iii protein secretion systems, in conjunction with the stimulation of innate immunity outputs throug ...200415469431
analysis of the mechanisms of salmonella-induced actin assembly during invasion of host cells and intracellular replication.salmonella enterica serovar typhimurium (s. typhimurium) induces actin assembly both during invasion of host cells and during the course of intracellular bacterial replication. in this study, we investigated the involvement in these processes of host cell signalling pathways that are frequently utilized by bacterial pathogens to manipulate the eukaryotic actin cytoskeleton. we confirmed that cdc42, rac, and arp3 are involved in s. typhimurium invasion of hela cells, and found that n-wasp and sca ...200415469433
salmonella enterica serovar typhimurium interaction with dendritic cells: impact of the sifa gene.salmonella enterica serovar typhimurium (s. typhimurium) and several mutant derivatives were able to enter efficiently murine bone marrow-derived dendritic cells using mechanisms predominantly independent of the salmonella pathogenicity island 1 type iii secretion system. the levels of intracellular bacteria did not increase significantly over many hours after invasion. using fluid endocytic tracers and other markers, s. typhimurium-containing vacuoles (scvs) were physically distinguishable from ...200415469435
modulation of arac family member activity by protein ligands.a number of arac family transcriptional activators bind low-molecular-weight ligands that modulate the activity of these proteins. recently, it has become clear that the activity of several virulence-related arac family members is regulated through the direct interaction of protein ligands. these interactions, in general, function to activate or repress the transcription of virulence genes in response to specific extracellular stimuli. the identification and characterization of several protein l ...200415469502
infective endocarditis due to salmonella typhi--a case report.endocarditis is a rare complication of typhoid fever. we report a case in which salmonella enterica serotype typhi was isolated from a case of endocarditis. the isolate was resistant to ampicillin, chloramphenicol and ciprofloxacin but sensitive to ceftriaxone, amikacin and gentamicin.200415471142
fluorescent amplified fragment length polymorphism subtyping of multiresistant salmonella enterica serovar typhimurium dt104.fluorescent amplified fragment length polymorphism (faflp) subtyping analysis was used to genotype multiresistant salmonella enterica serovar typhimurium definitive phage type 104. thirteen distinct faflp profiles were found among 85 isolates exhibiting identical pulsed-field gel electrophoresis (pfge) profiles. a single faflp profile was shared by 93% of outbreak-associated isolates and 82% of sporadic isolates. this study demonstrates the value of faflp as a high-resolution tool for epidemiolo ...200415472358
pediatric infection due to multiresistant salmonella enterica serotype infantis in honduras.we report the case of a pediatric patient with a salmonella enterica serotype infantis infection. detailed microbiological investigation revealed that this isolate carries four beta-lactamase genes (bla(tem-1b) variant, bla(shv-5), bla(ctx-m-15), and bla(cmy-2)) conferring resistance to all beta-lactams but imipenem. this is the first report of a salmonella isolate with ctx-m and ampc enzymes on the american continent, the first report of bla(cmy-2) in salmonella serotype infantis, and the first ...200415472372
genotypic diversity of salmonella enteritidis isolates from sporadic patients in limited area during one year.our aims were to investigate the genetic epidemiology of salmonella enterica serovar enteritidis (s. enteritidis) isolates using computerized analysis of restriction enzyme cleavage patterns.200415474626
[epidemiological analysis of salmonella enteritidis isolates using pulsed-field gel electrophoresis and bacteriophage typing over the period of april 2000 to march 2003 in gifu prefecture].we examined a total of 151 salmonella enterica serovar enteritidis strains isolated in gifu prefecture during the period from april 2000 to march 2003 by using bacteriophage typing and pulsed-field gel electrophoresis (pfge). bacteriophage typing classified them into twelve phage types (pt) and rdnc (reacted but did not conform). the predominant phage type was pt47 (34.4%) followed by pt1 (21.9%), pt4 (16.6%) and rdnc (11.3%). xbai- and blni-digested pfge analyses identified 17 and 44 pfge patte ...200415478644
antimicrobial resistance and phage types of human and non-human salmonella enterica isolates in ireland, 1998-2003.between 1998 and 2003, 5,161 isolates (3,182 human) of salmonella enterica were received by the national salmonella reference laboratory of ireland. serotyping, antimicrobial susceptibility testing and phage typing were performed by standard methods. the number of isolates of s. enterica serovar typhimurium decreased from 579 (80%) in 1998 to 208 (19%) in 2003, while s. enterica serovar enteritidis increased from 59 (8%) in 1998 to 219 (20%) in 2003. definitive (dt) phage types 104 and dt104b ac ...200415481212
cell density-dependent gene contributes to efficient seed colonization by pseudomonas putida kt2440.we have characterized the expression pattern of a gene, ddca, involved in initial colonization of corn seeds by pseudomonas putida kt2440. the ddca gene codes for a putative membrane polypeptide belonging to a family of conserved proteins of unknown function. members of this family are widespread among prokaryotes and include the products of a salmonella enterica serovar typhimurium gene expressed during invasion of macrophages and psie, an escherichia coli phosphate starvation-inducible gene. a ...200415345399
phenotypic and molecular typing of salmonella strains reveals different contamination sources in two commercial pig slaughterhouses.this study aimed to define the origin of salmonella contamination on swine carcasses and the distribution of salmonella serotypes in two commercial slaughterhouses during normal activity. salmonellae were isolated from carcasses, from colons and mesenteric lymph nodes of individual pigs, and from the slaughterhouse environment. all strains were serotyped; salmonella enterica serotype typhimurium and salmonella enterica serotype derby isolates were additionally typed beyond the serotype level by ...200415345414
phages and the evolution of bacterial pathogens: from genomic rearrangements to lysogenic conversion.comparative genomics demonstrated that the chromosomes from bacteria and their viruses (bacteriophages) are coevolving. this process is most evident for bacterial pathogens where the majority contain prophages or phage remnants integrated into the bacterial dna. many prophages from bacterial pathogens encode virulence factors. two situations can be distinguished: vibrio cholerae, shiga toxin-producing escherichia coli, corynebacterium diphtheriae, and clostridium botulinum depend on a specific p ...200415353570
antibacterial effect of crude water-soluble arrowroot (puerariae radix) tea extracts on food-borne pathogens in liquid medium.to evaluate the effect of crude water-soluble arrowroot tea extracts on microbial growth of food-borne pathogens in liquid medium and to confirm the damage to bacterial cells using transmission electronic microscopy (tem).200415355532
salmonella escape from antigen presentation can be overcome by targeting bacteria to fc gamma receptors on dendritic cells.dendritic cells (dcs) are professional apcs with the unique ability to activate naive t cells, which is required for initiation of the adaptive immune response against pathogens. therefore, interfering with dc function would be advantageous for pathogen survival and dissemination. in this study we provide evidence suggesting that salmonella enterica serovar typhimurium, the causative agent of typhoid disease in the mouse, interferes with dc function. our results indicate that by avoiding lysosom ...200415356155
antimicrobial resistance in nontyphoid salmonella serotypes: a global challenge.increasing antimicrobial resistance in nontyphoid salmonella species has been a serious problem for public health worldwide. the high rate of resistance is hampering the use of conventional antibiotics, and growing resistance to newer antimicrobial agents is aggravating the situation. the circumstances of occurrence and spread of antimicrobial resistance are complex; however, a major cause is the widespread use of antimicrobial agents in food animals, particularly in animal feed. genetic analysi ...200415356819
genomic relationship of salmonella enterica serovar typhimurium dt104 isolates from korea and the united states.salmonella enterica serovar typhimurium dt104 (salmonella typhimurium dt104 or dt104) has been emerging as a common pathogen for human in korea since 1997. in order to compare the genomic relationship and to search for the dominant strains in korea, we conducted pulsed-field gel electrophoresis (pfge) and is200 fingerprinting of 25 epidemiological unrelated isolates from human and animals from korea and cattle from america. two salmonella typhimurium dt104 isolates from human in korea and all 8 ...200415357286
characterization of the second long polar (lp) fimbriae of escherichia coli o157:h7 and distribution of lp fimbriae in other pathogenic e. coli strains.a second region containing five genes homologous to the long polar fimbrial operon of salmonella enterica serovar typhimurium is located in the chromosome of enterohemorrhagic escherichia coli (ehec) o157:h7. a non-fimbriated e. coli k-12 strain carrying the cloned ehec lpf (lpf2) genes expressed thin fibrillae-like structures on its surface and displayed reduced adherence to tissue culture cells. neither mutation in the lpfa2 gene in either the parent or lpfa1 mutant strains showed an effect in ...200415358418
characterization of extended-spectrum-beta-lactamase (ctx-m-15)-producing strains of salmonella enterica isolated in france and senegal.three clinical isolates of salmonella enterica recovered between 2000 and 2003 in france and senegal were found to produce extended-spectrum beta-lactamase ctx-m-15. the two isolates from senegal were recovered from stool of a hospitalized patient with gastroenteritis in 2000 and from an urine specimen of an out-patient with urinary tract infection in 2001. these s. enterica isolates belonged to serotype kentucky and were clonally related as determined by pulsed-field gel electrophoresis and aut ...200415358420
early interactions of salmonella enterica serovar typhimurium with human small intestinal epithelial explants.salmonella enterica serovar typhimurium (s typhimurium) causes invasive gastroenteritis in humans, a disease involving significant penetration of the intestinal mucosa. however, few studies have been undertaken to investigate this interaction directly using differentiated human gut tissue.200415361488
antibacterial activities of plant essential oils and their components against escherichia coli o157:h7 and salmonella enterica in apple juice.we evaluated 17 plant essential oils and nine oil compounds for antibacterial activity against the foodborne pathogens escherichia coli o157:h7 and salmonella enterica in apple juices in a bactericidal assay in terms of % of the sample that resulted in a 50% decrease in the number of bacteria (ba(50)). the 10 compounds most active against e. coli (60 min ba(50) range in clear juice, 0.018-0.093%) were carvacrol, oregano oil, geraniol, eugenol, cinnamon leaf oil, citral, clove bud oil, lemongrass ...200415366861
nosocomial outbreak of neonatal salmonella enterica serotype enteritidis meningitis in a rural hospital in northern tanzania.clinicians at haydom lutheran hospital, a rural hospital in northern tanzania noted an unusually high case-fatality rate of pediatric meningitis and suspected an outbreak of an unknown agent or an organism resistant to the empirical therapy.200415367335
multiple-locus variable-number tandem-repeats analysis of salmonella enterica subsp. enterica serovar typhimurium using pcr multiplexing and multicolor capillary electrophoresis.the multiple-locus variable-number tandem-repeats analysis (mlva) method is currently being used as the primary typing tool for salmonella enterica subsp. enterica serovar typhimurium (s. typhimurium) isolates in our laboratory. our published initial mlva was performed using a single fluorescent dye and the different patterns were assigned from gel images. here we present a new and significantly improved assay using multiple dye colors, enhanced pcr multiplexing and the introduction of two new l ...200415369852
connecting two-component regulatory systems by a protein that protects a response regulator from dephosphorylation by its cognate sensor.a fundamental question in signal transduction is how an organism integrates multiple signals into a cellular response. here we report the mechanism by which the salmonella pmra/pmrb two-component system responds to the signal controlling the phop/phoq two-component system. we establish that the phop-activated pmrd protein binds to the phosphorylated form of the response regulator pmra, preventing both its intrinsic dephosphorylation and that promoted by its cognate sensor kinase pmrb. this resul ...200415371344
persistent bacterial infections: the interface of the pathogen and the host immune system.persistent bacterial infections involving mycobacterium tuberculosis, salmonella enterica serovar typhi (s. typhi) and helicobacter pylori pose significant public-health problems. multidrug-resistant strains of m. tuberculosis and s. typhi are on the increase, and m. tuberculosis and s. typhi infections are often associated with hiv infection. this review discusses the strategies used by these bacteria during persistent infections that allow them to colonize specific sites in the host and evade ...200415372085
burkholderia pseudomallei stimulates low interleukin-8 production in the human lung epithelial cell line a549.melioidosis is a life-threatening disease caused by burkholderia pseudomallei. the lung is the most commonly affected organ, resulting in abscess formation in patients with chronic melioidosis. previous study has shown that b. pseudomallei was able to invade and multiply in epithelial cells. in the present study, we have demonstrated that b. pseudomallei is able to stimulate interleukin 8 (il-8) production from the human alveolar lung epithelium cell line a549. however, the level of il-8 product ...200415373906
relationships of the escherichia coli o157, o111, and o55 o-antigen gene clusters with those of salmonella enterica and citrobacter freundii, which express identical o antigens.escherichia coli o157, salmonella enterica o30, and citrobacter freundii f90 have identical o-antigen structures, as do e. coli o55 and s. enterica o50. the o-antigen gene cluster sequences for e. coli o157 and e. coli o55 have been published, and the genes necessary for o-antigen biosynthesis have been identified, although transferase genes for glycosidic linkages are only generic and have not been allocated to specific linkages. we determined sequences for s. enterica o30 and c. freundii f90 o ...200415375135
destruction of mycobacterium paratuberculosis, salmonella spp., and mycoplasma spp. in raw milk by a commercial on-farm high-temperature, short-time pasteurizer.the 2002 nahm's dairy survey indicated that 87.2% of dairy farms in the united states feed waste milk to their neonatal calves. although cost-effective, this practice can lead to increased calf morbidity and mortality due to ingestion of pathogenic agents. in an effort to reduce the risk of infection, dairy producers are implementing on-farm pasteurization of the waste milk as a control procedure before feeding the milk to calves. in the present study, the efficacy of a commercial high-temperatu ...200415328232
integral membrane protein p16 of bacteriophage prd1 stabilizes the adsorption vertex structure.the icosahedral membrane-containing double-stranded dna bacteriophage prd1 has a labile receptor binding spike complex at the vertices. this complex, which is analogous to that of adenovirus, is formed of the penton protein p31, the spike protein p5, and the receptor binding protein p2. upon infection, the internal phage membrane transforms into a tubular structure that protrudes through a vertex and penetrates the cell envelope for dna injection. we describe here a new class of prd1 mutants lac ...200415331712
elasticity of flagellar hooks. 200415332658
molecular characterization of beta-lactam resistance of salmonella isolates from pediatric patients in romania.the molecular characterization of 16 clinical isolates of salmonella enterica (14 serotype typhimurium and 2 serotype kingston) obtained between january and june 1999 from feces of children hospitalized in iasi, romania were genotypically compared by pulse field gel electrophoresis of xbai restricted bacterial dna. the majority of the clinical isolates (12/16) belonged to cluster a and (4/16) to unrelated strains, correlating to the omp profile. two major different patterns of beta-lactamases we ...200415332707
identification of nucleotides critical for activity of the sigmae-dependent rpoep3 promoter in salmonella enterica serovar typhimurium.we previously described a two-plasmid system for the identification of promoters recognized by salmonella enterica serovar typhimurium (s. typhimurium) sigmae. the s. typhimurium sigmae-dependent rpoep3 promoter was active in the e. coli two-plasmid system only after arabinose-induced expression of s. typhimurium rpoe. in the present study, we have exploited this two-plasmid system for the identification of nucleotides critical for activity of the rpoep3 promoter. a library of randomly mutated d ...200415336426
role of an acrr mutation in multidrug resistance of in vitro-selected fluoroquinolone-resistant mutants of salmonella enterica serovar typhimurium.quinolone resistance in salmonella spp. is usually attributed to both active efflux and mutations leading to modification of the target enzymes dna gyrase and topoisomerase iv. here, we investigated the presence of mutations in the efflux regulatory genes of fluoroquinolone- and multidrug-resistant mutants of salmonella enterica serovar typhimurium (s. typhimurium) selected in vitro with enrofloxacin that both carried a mutation in the target gene gyra and overproduced the acrab efflux pump. no ...200415336432
integrons in salmonella keurmassar, senegal. 200415338548
[purulent pericarditis with pericardial tamponade caused by streptococcus agalactiae and salmonella enterica no typhi].purulent pericarditis (pp) is an uncommon condition with high mortality. in the preantibiotic period, staphyloccocus aureus and streptococcus pneumoniae were the most common etiologic agents. we describe the case of a 75-year old man with septic shock, pp and cardiac tamponade caused by streptococcus agalactiae and salmonella enterica no-typhi. to our knowledge this association of pathogenic organisms has not been previously reported in the literature. the pathogenesis is here reviewed, and in o ...200415338978
cloning, sequencing and expression of groel-like protein gene of vibrio parahaemolyticus.vibrio parahaemolyticus is an important enteropathogen in regions where much seafood is consumed. substantial quantity of groel-like protein is produced during the heat shock of v. parahaemolyticus and located in periplasmic and extracellular fractions. in this study, the groel-like protein gene of this pathogen was cloned and sequenced and its properties were analyzed. the open reading frame consisted of 1647 bp, encoded a 57.6-kda groel-like protein of 548 amino acids. the amino acid sequence, ...200415340646
rapid screening method for the detection of antimicrobial substances.bioluminescence is phenomenon where living organisms produce light and this production is directly dependent on metabolic activity of the organism. genes encoding enzymes, luciferases, responsible for light production can be cloned into indicator strains, thus allowing sensitive detection of antimicrobial activity. this study utilized bacterial luciferase genes cloned into staphylococcus aureus, escherichia coli and salmonella enterica serovar typhimurium indicator strains and showed that the de ...200415003685
random amplified polymorphic dna and phenotyping analysis of salmonella enterica serovar enteritidis isolates collected from humans and poultry in uruguay from 1995 to 2002.molecular and phenotyping techniques were applied to study salmonella enterica serovar enteritidis strains both from human cases of infection and of avian origin isolated in uruguay from 1995 to 2002. a group of 62 isolates was subjected to random amplified polymorphic dna (rapd) assay and analysis of antibiotic resistance patterns. twenty-one of these strains were further characterized by phage typing and analysis of their protein expression profiles. rapd fingerprinting with five different pri ...200415004068
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