Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| bacteria-mediated dna transfer in gene therapy and vaccination. | the use of live attenuated bacterial vaccine strains allows the targeted delivery of macromolecules to mammalian cells and tissues via the mucosal route. depending on their specific virulence mechanisms and inherent metabolic preferences, bacteria invade certain cell types and body niches where they consequently deliver their cargo. recently, the ability of attenuated strains of salmonella, shigella and yersinia spp., as well as listeria monocytogenes and invasive escherichia coli, to deliver eu ... | 2004 | 14998775 |
| efficacy and tolerability of clo2-generating gloves. | the transmission of pathogenic microorganisms by the hands of workers continues to be a problem in the medical field and the food industry. compliance with hand hygiene is often poor, and gloves may be contaminated after being donned and may transmit microorganisms. a novel, patented technology allows materials to be impregnated with microspheres that, when activated by light or moisture, generate clo2 at sustained rates to produce a disinfecting microatmosphere. gloves that were seeded with bac ... | 2004 | 14999631 |
| cytotoxic t-lymphocyte-, and helper t-lymphocyte-oriented dna vaccination. | dna vaccines have advantages over other types of vaccines in that they can induce strong cellular immune responses, namely cytotoxic t lymphocytes (ctl) and helper t lymphocytes (th). dna vaccines are therefore considered a promising alternative to attenuated live vaccines in the field of infectious diseases. so far, various dna vaccines have been generated and tried to induce a particular cellular immune response by virtue of recombinant dna technology. dna vaccines have been designed for effic ... | 2004 | 15000749 |
| folding and stability of the leucine-rich repeat domain of internalin b from listeri monocytogenes. | internalin b (inlb), a surface protein of the human pathogen listeria monocytogenes, promotes invasion into various host cell types by inducing phagocytosis of the entire bacterium. the n-terminal half of inlb (residues 36-321, inlb321), which is sufficient for this process, contains a central leucine-rich repeat (lrr) domain that is flanked by a small alpha-helical cap and an immunoglobulin (ig)-like domain. here we investigated the spectroscopic properties, stability and folding of inlb321 and ... | 2004 | 15003459 |
| suppurative gastritis in balb/c mice infected with listeria monocytogenes via the intragastric route. | suppurative gastritis was demonstrated in balb/c mice 3 days after intragastric inoculation with 10(9) organisms of listeria monocytogenes strain atcc19113 (serotype 3). also tested were four other strains of mice (c3h, c57bl/6, fvb and icr) and three other strains of l. monocytogenes (hpb 3 [serotype 4b], hpb 410 [serotype 1/2a] and hpb 503 [serotype 1/2b]). after inoculation with atcc19113 the numbers of bacteria found in the stomach wall were greater in c57bl/6 and icr mice than in c3h and fv ... | 2004 | 15003470 |
| evaluation of the microfoss system for the detection of listeria species in environmental samples. | the microfoss system was evaluated for its ability to detect listeria species in environmental samples. the sensitivity and specificity of the microfoss were determined in relation to a standard culture method for listeria detection. the sensitivities of both the microfoss and standard culture methods were similar (88.4%-microfoss, 90.7%-culture) based on the total number of positive results obtained by both methods. the microfoss system detected listeria spp. in 12 samples, which were not detec ... | 2004 | 15003682 |
| cutting edge: long-lived cd8 memory and protective immunity in the absence of cd40 expression on cd8 t cells. | cd8 t cells need cd4 t cells to develop into long-lived, functional memory cells that provide protection against pathogen rechallenge. we investigated whether signaling via cd40 expressed on the cd8 cells themselves is involved in this cooperation. in murine responses to listeria monocytogenes and lymphocytic choriomeningitis virus, we found no evidence of any requirement for cd40-cd40 ligand interaction at this level. no differences were observed between cd40(-/-) and cd40(+/+) cd8 t cells that ... | 2004 | 15004136 |
| prolonged antigen presentation, apc-, and cd8+ t cell turnover during mycobacterial infection: comparison with listeria monocytogenes. | we expressed the ctl epitope of ova (ova(257-264)) in an acute (listeria monocytogenes (lm)-ova) and a chronic intracellular pathogen (mycobacterium bovis (bcg)-ova), to evaluate the kinetics of ag presentation. lm-ova proliferated rapidly in vivo, resulting in profound lm-ova expansion within the first 24 h of infection, culminating in the generation of a potent cd8+ t cell response, which peaked on day 7 but underwent a rapid attrition subsequently. in contrast, bcg-ova exhibited reduced growt ... | 2004 | 15004149 |
| increased dendritic cell numbers impair protective immunity to intracellular bacteria despite augmenting antigen-specific cd8+ t lymphocyte responses. | dendritic cells (dcs) reside in tissues, where they function as sentinels, providing an essential link between innate and adaptive immunity. increasing the numbers of dcs in vivo augments t cell responses, and can cause dramatic ctl-dependent tumor regression. to determine whether greater dc numbers promoted t cell-mediated protection in the context of host defense against intracellular bacteria, we treated mice with flt3 ligand (flt3-l) to increase dcs in vivo and challenged them with listeria ... | 2004 | 15004177 |
| biophysical parameters influence actin-based movement, trajectory, and initiation in a cell-free system. | using a biochemically complex cytoplasmic extract to reconstitute actin-based motility of listeria monocytogenes and polystyrene beads coated with the bacterial protein acta, we have systematically varied a series of biophysical parameters and examined their effects on initiation of motility, particle speed, speed variability, and path trajectory. bead size had a profound effect on all aspects of motility, with increasing size causing slower, straighter movement and inhibiting symmetry-breaking. ... | 2004 | 15004224 |
| listeria monocytogenes actin-based motility varies depending on subcellular location: a kinematic probe for cytoarchitecture. | intracellular listeria monocytogenes actin-based motility is characterized by significant individual variability, which can be influenced by cytoarchitecture. l. monocytogenes was used as a probe to transmit information about structural variation among subcellular domains defined by mitochondrial density. by analyzing the movement of a large population of l. monocytogenes in ptk2 cells, we found that mean speed and trajectory curvature were significantly larger for bacteria moving in mitochondri ... | 2004 | 15004231 |
| quantitative detection of listeria monocytogenes and listeria innocua by real-time pcr: assessment of hly, iap, and lin02483 targets and amplifluor technology. | we developed and assessed real-time pcr (rti-pcr) assays for the detection and quantification of the food-borne pathogen listeria monocytogenes and the closely related nonpathogenic species l. innocua. the target genes were hly and iap for l. monocytogenes and lin02483 for l. innocua. the assays were 100% specific, as determined with 100 listeria strains and 45 non-listeria strains, and highly sensitive, with detection limits of one target molecule in 11 to 56% of the reactions with purified dna ... | 2004 | 15006755 |
| characteristics of a new enantioselective thermostable dipeptidase from brevibacillus borstelensis bcs-1 and its application to synthesis of a d-amino-acid-containing dipeptide. | a new thermostable dipeptidase gene was cloned from the thermophile brevibacillus borstelensis bcs-1 by genetic complementation of the d-glu auxotroph escherichia coli wm335 on a plate containing d-ala-d-glu. nucleotide sequence analysis revealed that the gene included an open reading frame coding for a 307-amino-acid sequence with an m(r) of 35,000. the deduced amino acid sequence of the dipeptidase exhibited 52% similarity with the dipeptidase from listeria monocytogenes. the enzyme was purifi ... | 2004 | 15006780 |
| pbp2229-mediated nisin resistance mechanism in listeria monocytogenes confers cross-protection to class iia bacteriocins and affects virulence gene expression. | it was previously shown that enhanced nisin resistance in some mutants was associated with increased expression of three genes, pbp2229, hpk1021, and lmo2487, encoding a penicillin-binding protein, a histidine kinase, and a protein of unknown function, respectively. in the present work, we determined the direct role of the three genes in nisin resistance. interruption of pbp2229 and hpk1021 eliminated the nisin resistance phenotype. interruption of hpk1021 additionally abolished the increase in ... | 2004 | 15006792 |
| maternal listeriosis in pregnancy associated with measles virus infection. | a case of maternal listeriosis associated with measles infection is described. maternal listeriosis without fetal or neonatal involvement is relatively rare. this case was diagnosed early and treated appropriately, and the baby showed no symptoms or signs of feto-maternal infection. | 2004 | 15009615 |
| auto, a surface associated autolysin of listeria monocytogenes required for entry into eukaryotic cells and virulence. | listeria monocytogenes is an opportunistic food-borne human and animal pathogen. several surface proteins expressed by this intracellular pathogen are critical for the infectious process. by in silico analysis we compared the surface protein repertories of l. monocytogenes and of the non-pathogenic species listeria innocua and identified a gene encoding a surface protein of l. monocytogenes absent in l. innocua. this gene that we named aut encodes a protein (auto) of 572 amino acids containing a ... | 2004 | 15009888 |
| influence of bovine manure as fertilizer on the bacteriological quality of organic iceberg lettuce. | to investigate the bacteriological quality, and the occurrence of selected pathogenic bacteria from organically grown iceberg lettuce fertilized with bovine manure in the form of compost, firm manure and slurry in a 2-year field trial. | 2004 | 15012817 |
| the interplay between classical and alternative isoprenoid biosynthesis controls gammadelta t cell bioactivity of listeria monocytogenes. | isoprenoids are synthesised either through the classical, mevalonate pathway, or the alternative, non-mevalonate, 2-c-methyl-d-erythritol 4-phosphate (mep) pathway. the latter is found in many microbial pathogens and proceeds via (e)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (hmb-pp), a potent activator of human vgamma9/vdelta2 t cells. listeria monocytogenes is the only pathogenic bacterium known to contain both pathways concurrently. strategic gene knockouts demonstrate that either pathway i ... | 2004 | 15013758 |
| listeria monocytogenes-induced endogenous endophthalmitis: bioultrasonic findings. | to report bioultrasonic findings in listeria monocytogenes-induced endophthalmitis (lmie) that have not been described previously. | 2004 | 15013893 |
| comparative genomic analysis of the sigb operon in listeria monocytogenes and in other gram-positive bacteria. | the stress-responsive, alternative sigma factor sigmab has been described in members of three gram-positive genera, bacillus, listeria, and staphylococcus. in these bacteria, sigmab appears to play an important role in facilitating rapid adaptation to and survival in stressful environments. sigmab activity is regulated through a complex system of phosphatases and kinases encoded by rsb (regulator of sigma b) genes. we describe the sigb operon structure for the facultative intracellular pathogen ... | 2004 | 15018101 |
| characterization of the calcium-binding sites of listeria monocytogenes inlb. | the listeria monocytogenes protein inlb promotes invasion of mammalian cells through activation of the receptor tyrosine kinase met. the inlb n-cap, a approximately 40 residue part of the domain that binds met, was previously observed to bind two calcium ions in a novel and unusually exposed manner. because subsequent work raised questions about the existence of these calcium-binding sites, we assayed calcium binding in solution to the inlb n-cap. we show that calcium ions are bound with dissoci ... | 2004 | 15020228 |
| does etanercept monotherapy enhance the risk of listeria monocytogenes meningitis? | 2004 | 15020347 | |
| sortase b, a new class of sortase in listeria monocytogenes. | sortases are transamidases that covalently link proteins to the peptidoglycan of gram-positive bacteria. the genome of the pathogenic bacterium listeria monocytogenes encodes two sortases genes, srta and srtb. the srta gene product anchors internalin and some other lpxtg-containing proteins to the listerial surface. here, we focus on the role of the second sortase, srtb. whereas srta acts on most of the proteins in the peptidoglycan fraction, srtb appears to target minor amounts of surface polyp ... | 2004 | 15028680 |
| preventing listeria contamination in foods. | keeping ready-to-eat foods cold is key to reducing listeriosis, a serious infection in humans. that's one of the conclusions of a recent food and drug administration risk assessment on the relationships between foodborne listeriosis and human health. | 2004 | 15032197 |
| listeria monocytogenes and listeriosis: a review of hazard characterisation for use in microbiological risk assessment of foods. | considerable effort has been put into the application of quantitative microbiological risk assessment for listeria monocytogenes, and data are available for england and wales (probably more so than most other countries) on the adverse health effects, together with incidence data on different age and risk groups for human l. monocytogenes infections. this paper reviews aspects of listeria and human listeriosis, especially from a public health perspective and provide hazard characterisation data, ... | 2004 | 15033265 |
| growth of listeria monocytogenes in melon, watermelon and papaya pulps. | growth of listeria monocytogenes in low-acid fruits (melon, watermelon and papaya) at different times of incubation and at temperatures of 10, 20 and 30 degrees c was studied. fruit pulp portions with an average ph of 5.87, 5.50 and 4.87 for melon, watermelon and papaya, respectively, were obtained aseptically, homogenized, weighed and inoculated with suspensions (approximately 10(2) cfu/g) of l. monocytogenes. generation times of 7.12, 13.03 and 15.05 h at 10 degrees c, 1.74, 2.17 and 6.42 h at ... | 2004 | 15033271 |
| effects of several environmental factors on the anti-listeria monocytogenes activity of an essential oil of picea excelsa. | the effects of several environmental factors on the anti-listeria monocytogenes activity of an essential oil of picea excelsa were explored by determination of active concentrations using two methods and with survival curves. in trial conditions, the serovars 1/2c and 4b behaved similarly. a dose of 0.2-0.3% (v/v) of essential oil was bactericidal for 10(5)-10(7) cells contained in 1 ml of tryptone soy broth yeast extract at ph 6 and 7 incubated at 13 and 37 degrees c and of medium supplemented ... | 2004 | 15033272 |
| subpopulations of mouse blood monocytes differ in maturation stage and inflammatory response. | blood monocytes are well-characterized precursors for macrophages and dendritic cells. subsets of human monocytes with differential representation in various disease states are well known. in contrast, mouse monocyte subsets have been characterized minimally. in this study we identify three subpopulations of mouse monocytes that can be distinguished by differential expression of ly-6c, cd43, cd11c, mbr, and cd62l. the subsets share the characteristics of extensive phagocytosis, similar expressio ... | 2004 | 15034056 |
| the ly-6chigh monocyte subpopulation transports listeria monocytogenes into the brain during systemic infection of mice. | mononuclear phagocytes can be used by intracellular pathogens to disseminate throughout the host. in the bloodstream these cells are generically referred to as monocytes. however, blood monocytes are a heterogeneous population, and the exact identity of the leukocyte(s) relevant for microbial spreading is not known. experiments reported in this study used listeria monocytogenes-infected mice to establish the phenotype of parasitized blood leukocytes and to test their role in systemic disseminati ... | 2004 | 15034057 |
| attachment of listeria monocytogenes on ready-to-eat meats. | five individual strains of listeria monocytogenes and a mixed cocktail of all five were studied for attachment on frankfurters, ham, bologna, and roast beef relative to their cell surface characteristics. the ratio of strongly attached (sessile) l. monocytogenes cells compared with total (sessile and planktonic) attached cells on ready-to-eat meats was also determined. because bacterial cell surfaces were characterized by net negative charge and hydrophobicity, electrostatic interaction chromato ... | 2004 | 15035357 |
| temperature effect on listeria monocytogenes growth in the event of contamination of cooked pork products. | the aim of this study was to describe the effect of temperature on the growth of listeria monocytogenes in the event of postprocess contamination of packaged pork meats. this study was carried out in two steps. in the first step, the effect of temperature on l. monocytogenes growth rates was determined in duplicates at 13 temperatures between 2 and 43 degrees c by turbidimetric methods and adjusted by a quantitative secondary model. then, seven sets of growth kinetics were collected by challenge ... | 2004 | 15035358 |
| radiation resistance and virulence of listeria monocytogenes scott a following starvation in physiological saline. | the influence of starvation on the resistance of listeria monocytogenes scott a to electron beam irradiation in 0.85% (wt/vol) nacl (saline) and in ground pork was investigated. exponential- or stationary-phase cells (control) were grown at 35 degrees c in tryptic soy broth supplemented with 0.6% yeast extract. washed cells were starved for 12 days in saline, and virulence of the pathogen was evaluated at 0, 8, and 12 days during starvation. samples of saline and irradiation-sterilized ground po ... | 2004 | 15035359 |
| development and characterization of an antimicrobial packaging film coating containing nisin for inhibition of listeria monocytogenes. | the purpose of this study was to develop and characterize a packaging film coating containing nisin. a spot-on-lawn assay was used to determine the effect of acid type (ascorbic, acetic, hydrochloric, lactic) and nisin level (equal increments from 10,000 iu to 9 iu) to be used in the formulation of the film coating. zones of inhibition were measured after incubation on tryptic soy agar (37 degrees c, 48 h). low-density polyethylene films coated with differing levels of nisin were characterized b ... | 2004 | 15035360 |
| inhibition of listeria monocytogenes on the surface of individually packaged hot dogs with a packaging film coating containing nisin. | the objective of this study was to determine the effectiveness of packaging films coated with a methylcellulose/hydroxypropyl methylcellulose-based solution containing 10,000, 7,500, 2,500, or 156.3 iu/ml nisin for controlling listeria monocytogenes on the surfaces of vacuum-packaged hot dogs. barrier film coated with a methylcellulose/hydroxypropyl methylcellulose-based solution containing nisin or no nisin (control) was heat sealed to form individual pouches. hot dogs were placed in control an ... | 2004 | 15035361 |
| membrane fusion induced by the catalytic activity of a phospholipase c/sphingomyelinase from listeria monocytogenes. | listeria monocytogenes is a bacterium responsible for localized and generalized infections in humans and animals. it has the ability to spread from the cytoplasm of an infected cell to neighboring cells without becoming exposed to the extracellular space. the bacterium secretes a phospholipase c (plc(lm)) that is active on glycerophospholipids, e.g., phosphatidylcholine, and on sphingomyelin; thus, plc(lm) should be described more appropriately as a phospholipase c/sphingomyelinase. we have obta ... | 2004 | 15035639 |
| t cell responses to listeria monocytogenes. | owing to its unique intracellular biology that allows it to gain access to the host cell cytosol, listeria monocytogenes induces potent, protective cd8 responses. the study of these responses has served as a paradigm to understand cell-mediated immunity to microbial pathogens. the availability of mutants specifically defective in unique aspects of the intracellular biology of this pathogen has greatly aided these studies. during the past few years, progress has been made to understand the contri ... | 2004 | 15036139 |
| dendritic cells: the host achille's heel for mucosal pathogens? | mucosal surfaces represent the main sites of interaction with environmental microorganisms and antigens. sentinel cells, including epithelial cells and dendritic cells (dcs), continuously sense the environment and coordinate defenses for the protection of mucosal tissues. dcs play a central role in the control of adaptive immune responses owing to their capacity to internalize foreign materials, to migrate into lymph nodes and to present antigens to naive lymphocytes. some pathogenic microorgani ... | 2004 | 15036324 |
| the probiotic escherichia coli strain nissle 1917 interferes with invasion of human intestinal epithelial cells by different enteroinvasive bacterial pathogens. | the probiotic escherichia coli strain nissle 1917 (mutaflor) of serotype o6:k5:h1 was reported to protect gnotobiotic piglets from infection with salmonella enterica serovar typhimurium. an important virulence property of salmonella is invasion of host epithelial cells. therefore, we tested for interference of e. coli strain nissle 1917 with salmonella invasion of int407 cells. simultaneous administration of e. coli strain nissle 1917 and salmonella resulted in up to 70% reduction of salmonella ... | 2004 | 15039098 |
| injury recovery of foodborne pathogens in high hydrostatic pressure treated milk during storage. | bacteria are expected to be injured or killed by high hydrostatic pressure (hhp). this depends on pressure levels, species and strain of the microorganism and subsequent storage. injured bacteria may be repaired which could affect the microbiological quality of foodstuffs with an important safety consideration especially in low acid food products. in this study two gram-positive (listeria monocytogenes ca and staphylococcus aureus 485) and two gram-negative (escherichia coli o157:h7 933 and salm ... | 2004 | 15039101 |
| induction of protective cellular immunity against mycobacterium tuberculosis by recombinant attenuated self-destructing listeria monocytogenes strains harboring eukaryotic expression plasmids for antigen 85 complex and mpb/mpt51. | we report here the induction of specific protective cellular immunity against mycobacterium tuberculosis by the employment of vaccination with recombinant attenuated listeria monocytogenes strains. we constructed self-destructing attenuated l. monocytogenes delta 2 strains carrying eukaryotic expression plasmids for the antigen 85 complex (ag85a and ag85b) and for mpb/mpt51 (mycobacterial protein secreted by m. bovis bcg/mycobacterial protein secreted by m. tuberculosis) molecules. infection of ... | 2004 | 15039321 |
| toll-like receptor 2 is required for optimal control of listeria monocytogenes infection. | the control of listeria monocytogenes infection depends on the rapid activation of the innate immune system, likely through toll-like receptors (tlr), since mice deficient for the common adapter protein of tlr signaling, myeloid differentiation factor 88 (myd88), succumb to listeria infection. in order to test whether tlr2 is involved in the control of infections, we compared the host response in tlr2-deficient mice with that in wild-type mice. here we show that tlr2-deficient mice are more susc ... | 2004 | 15039335 |
| dna vaccination with gp96-peptide fusion proteins induces protection against an intracellular bacterial pathogen. | effective vaccination using in vitro peptide-loaded heat-shock proteins (hsp), tumor-derived hsp and hsp fusion proteins has been shown in viral, parasite and tumor model systems. we demonstrate protective dna vaccination using gp96-peptide fusion proteins against the intracellular bacterial pathogen listeria monocytogenes in a mouse model. in contrast to previous studies using pathogen-derived hsp as vaccine vehicles, we used recombinant endogenous (mus musculus) gp96 (grp94) as a carrier for i ... | 2004 | 15039390 |
| p47 gtpases: regulators of immunity to intracellular pathogens. | activation of the innate immune system by interferon-gamma (ifn-gamma is crucial for host resistance to infection. ifn-gamma induces the expression of a wide range of mediators that undermine the ability of pathogens to survive in host cells, including a newly discovered family of 47-kda gtpases. elimination of different p47 gtpases in mice by gene targeting severely cripples ifn-gamma-regulated defence against toxoplasma gondii, listeria monocytogenes, mycobacterium spp. and other pathogens. in ... | 2004 | 15040583 |
| prevalence of antimicrobial resistance in bacteria isolated from central nervous system specimens as reported by u.s. hospital laboratories from 2000 to 2002. | bacterial infections of the central nervous system, especially acute infections such as bacterial meningitis require immediate, invariably empiric antibiotic therapy. the widespread emergence of resistance among bacterial species is a cause for concern. current antibacterial susceptibility data among central nervous system (cns) pathogens is important to define current prevalence of resistance. | 2004 | 15043754 |
| listeria monocytogenes: comparative interpretation of mouse virulence assay. | being an opportunistic bacterial pathogen, listeria monocytogenes demonstrates significant strain variations in virulence and pathogenicity. the availability of laboratory procedures to ascertain the pathogenic potential of l. monocytogenes bacteria would greatly enhance the control and prevention of listerial infections. as a method that measures all virulent determinants, mouse virulence assay has been frequently used for assessing l. monocytogenes virulence. the pathogenic potential of a give ... | 2004 | 15043883 |
| a generic approach for the detection of whole listeria monocytogenes cells in contaminated samples using surface plasmon resonance. | the opportunistic food pathogen listeria monocytogenes is of great concern to the food industry and its rapid detection is of major importance. this paper describes the detection of l. monocytogenes with a polyclonal antibody by means of a new subtractive inhibition assay using a biacore 3000 biosensor. incubating l. monocytogenes cells and antibody for a short period of time, followed by subsequent separation of free unbound antibody with a stepwise centrifugation process, allowed the detection ... | 2004 | 15046767 |
| protection from bacterial infection by a single vaccination with replication-deficient mutant herpes simplex virus type 1. | adaptive immune responses in which cd8(+) t cells recognize pathogen-derived peptides in the context of major histocompatibility complex class i molecules play a major role in the host defense against infection with intracellular pathogens. cells infected with intracellular bacteria such as listeria monocytogenes, salmonella enterica serovar typhimurium, or mycobacterium tuberculosis are directly lysed by cytotoxic cd8(+) t cells. for this reason, current vaccines for intracellular pathogens, su ... | 2004 | 15047818 |
| mini-review: presentation of pathogen-derived antigens in vivo. | most intracellular pathogens induce robust t cell responses upon infection of mammalian hosts. in most cases, these t cell responses are protective and result in pathogen clearance. it is therefore important to determine how t cells are primed and how they differentiate into cytokine-secreting and/or cytotoxic effector cells. in contrast to b cells, which recognize soluble ag, cd8(+) and cd4(+) t cells react to ag-derived peptides bound to mhc i or mhc ii molecules, respectively. therefore, eluc ... | 2004 | 15048701 |
| in vitro transcription of the listeria monocytogenes virulence genes inlc and mpl reveals overlapping prfa-dependent and -independent promoters that are differentially activated by gtp. | most known virulence genes of listeria monocytogenes are regulated by the transcriptional factor prfa. using our recently established in vitro transcription system, we have studied the prfa-dependent promoter (pinlc) regulating the expression of the small, secreted internalin c. prfa-dependent and prfa-independent transcription is observed starting from pinlc in vitro and in vivo, suggesting the presence of two apparently overlapping promoters both of which use the same -10 box. although the prf ... | 2004 | 15049809 |
| gw domains of the listeria monocytogenes invasion protein inlb are required for potentiation of met activation. | the listeria monocytogenes protein inlb promotes intracellular invasion by activating the receptor tyrosine kinase met. earlier studies have indicated that the lrr fragment of inlb is sufficient for met activation, but we show that this is not the case unless the lrr fragment is artificially dimerized through a disulphide bond. in contrast, activation of met proceeds through monomers of intact inlb and, at physiologically relevant concentrations, requires coordinated action in cis of both inlb n ... | 2004 | 15049825 |
| characterization of listeria monocytogenes and listeria innocua from a vegetable processing plant by rapd and rea. | the incidence of listeria monocytogenes in a vegetable processing plant was investigated over a 23-month period. frozen ready-to-eat vegetable samples, well as the plant environment, were sampled. the molecular subtyping techniques, random amplified polymorphic dna (rapd) and restriction endonuclease analyses (rea), were performed to help investigate the origin and routes of listeria dissemination. the low and sporadic incidence of l. monocytogenes made it impossible to establish an epidemiologi ... | 2004 | 14751689 |
| occurrence of listeria monocytogenes in fresh and processed foods in navarra (spain). | the presence of listeria spp. was investigated in a total of 3685 food samples obtained from different industries and markets of northern spain in the last 4 years. the samples analyzed include fresh raw products (meat, milk and poultry) and treated products (cooked and cured meats, frozen vegetables and smoked salmon). occurrence of listeria spp. varied from 8.1% in soft cheese to 76.3% in raw poultry samples. the highest incidence of l. monocytogenes also occurred in raw poultry (36.1% positiv ... | 2004 | 14751690 |
| caat-box, contigs-assembly and annotation tool-box for genome sequencing projects. | contigs-assembly and annotation tool-box (caat-box) is a software package developed for the computational part of a genome project where the sequence is obtained by a shotgun strategy. caat-box contains new tools to predict links between contigs by using similarity searches with other whole genome sequences. most importantly, it allows annotation of a genome to commence during the finishing phase using a gene-oriented strategy. for this purpose, caat-box creates an individual protein file (ipf) ... | 2004 | 14752000 |
| [meningitis by listeria in children]. | listeria monocytogenes is a rare cause of bacterial meningoencephalitis in the non-immunocompromised pediatric population. on occasions, the absence of differential characteristics with other bacteria that cause meningitis delays diagnosis and hence treatment, worsening the prognosis. | 2004 | 14752714 |
| [listeriosis in patients with human immunodeficiency virus infection in spain. three new cases and literature review]. | listeriosis has been considered infrequent among patients infected with the human immunodeficiency virus (hiv). only a limited number of listeriosis cases among hiv-infected patients have been published in spain, where the prevalence of hiv infection is relatively high. we present our experience in this field and provide a review of the reported cases in our country. | 2004 | 14757003 |
| [listeria monocytogenes meningitis in an immunocompetent girl]. | 2004 | 14757026 | |
| signs of spinal cord disease in two heifers caused by listeria monocytogenes. | 2004 | 14758832 | |
| recurrent listeria monocytogenes aortic graft infection: confirmation of relapse by molecular subtyping. | based on molecular typing methods, we identified a rare case of a recurrent l. monocytogenes infection resulting from an infected aortic prosthesis as detected by 18-f-fluoro-d-deoxyglucose positron emission tomography (fdg pet). our case highlights the usefulness of molecular typing and nuclear imaging methods for understanding l. monocytogenes pathogenesis and epidemiology. | 2004 | 14761724 |
| clpb, a novel member of the listeria monocytogenes ctsr regulon, is involved in virulence but not in general stress tolerance. | clp-hsp100 atpases are a widespread family of ubiquitous proteins that occur in both prokaryotes and eukaryotes and play important roles in the folding of newly synthesized proteins and refolding of aggregated proteins. they have also been shown to participate in the virulence of several pathogens, including listeria monocytogenes. here, we describe a member of the clp-hsp100 family of l. monocytogenes that harbors all the characteristics of the clpb subclass, which is absent in the closely rela ... | 2004 | 14762012 |
| characterization of flagellin expression and its role in listeria monocytogenes infection and immunity. | flagellin is the structural component of flagella produced by many pathogenic bacteria and is a potent proinflammatory molecule that mediates these effects through toll-like receptor (tlr) 5. in listeria monocytogenes (lm), flagellin expression is regulated by temperature and has been described as being shut off at 37 degrees c. in this study, we demonstrate that tlr5-mediated cell activation and flagellin expression is maintained at 37 degrees c in some laboratory-adapted strains and in approxi ... | 2004 | 14764107 |
| cutting edge: toll-like receptor signaling in macrophages induces ligands for the nkg2d receptor. | macrophages recognize the presence of infection by using the toll-like receptor (tlr) family of proteins that detect ligands on bacterial, viral, and fungal pathogens. we show that murine macrophages stimulated with pathogen products known to signal through tlrs express ligands for the nkg2d receptor, found on nk cells, activated cd8(+) t cells and activated macrophages. tlr signaling, through the myd88 adaptor, up-regulates transcription of the retinoic acid early inducible-1 (rae-1) family of ... | 2004 | 14764662 |
| extracellular replication of listeria monocytogenes in the murine gall bladder. | the bacterium listeria monocytogenes can cause a life-threatening systemic illness in humans. despite decades of progress in animal models of listeriosis, much remains unknown about the processes of infection and colonization. here, we report that l. monocytogenes can replicate in the murine gall bladder and provide evidence that its replication there is extracellular and intraluminal. in vivo bioluminescence imaging was employed to determine the location of the infection over time in live anima ... | 2004 | 14764883 |
| a portable array biosensor for detecting multiple analytes in complex samples. | the multi-analyte array biosensor (maab) has been developed at the naval research laboratory (nrl) with the goal of simultaneously detecting and identifying multiple target agents in complex samples with minimal user manipulation. this paper will focus on recent improvements in the biochemical and engineering aspects of this instrument. these improvements have enabled the expansion of the repertoire of analytes detected to include salmonella typhimurium and listeria monocytogenes, and also expan ... | 2004 | 14765282 |
| multi-virulence-locus sequence typing of listeria monocytogenes. | a multi-virulence-locus sequence typing (mvlst) scheme was developed for subtyping listeria monocytogenes, and the results obtained using this scheme were compared to those of pulsed-field gel electrophoresis (pfge) and the published results of other typing methods, including ribotyping (rt) and multilocus sequence typing (mlst). a set of 28 strains (eight different serotypes and three known genetic lineages) of l. monocytogenes was selected from a strain collection (n > 1,000 strains) to repres ... | 2004 | 14766571 |
| development and validation of experimental protocols for use of cardinal models for prediction of microorganism growth in food products. | an experimental protocol to validate secondary-model application to foods was suggested. escherichia coli, listeria monocytogenes, bacillus cereus, clostridium perfringens, and salmonella were observed in various food categories, such as meat, dairy, egg, or seafood products. the secondary model validated in this study was based on the gamma concept, in which the environmental factors temperature, ph, and water activity (aw) were introduced as individual terms with microbe-dependent parameters, ... | 2004 | 14766591 |
| deregulation of listeria monocytogenes virulence gene expression by two distinct and semi-independent pathways. | expression of the major virulence cluster in listeria monocytogenes is positively regulated by the transcription factor prfa and is influenced by several environmental factors, including the presence of readily metabolized carbohydrates such as cellobiose and glucose. although little is understood about the mechanisms through which environmental factors influence expression of the prfa regulon, evidence for structural and functional similarities of prfa to the crp-fnr family of regulatory protei ... | 2004 | 14766910 |
| physiological implications of class iia bacteriocin resistance in listeria monocytogenes strains. | high-level resistance to class iia bacteriocins has been directly associated with the absent eiiab(man) (mpta) subunit of the mannose-specific phosphoenolpyruvate-dependent phosphotransferase system (pts) (eiit(man)) in listeria monocytogenes strains. class iia bacteriocin-resistant strains used in this study were a spontaneous resistant, l. monocytogenes b73-mr1, and a defined mutant, l. monocytogenes egde-mpta. both strains were previously reported to have the eiiab(man) pts component missing. ... | 2004 | 14766911 |
| the cd8 population in cd4-deficient mice is heavily contaminated with mhc class ii-restricted t cells. | in experiments to study the impact of deficiency in cd4+ t cell help on the magnitude of cd8+ cytotoxic t cell response to pathogens, it was noted that in cd4 gene knockout mice, the cd8 population made significant responses to several nominally major histocompatibility complex (mhc) class ii-restricted epitopes in addition to the expected responses to mhc class i-restricted epitopes. a similar response by cd8+ t cells to class ii-restricted epitopes was not observed in wild-type mice, or in mic ... | 2004 | 14769854 |
| listeriosis in the pregnant guinea pig: a model of vertical transmission. | feto-placental infections represent a major cause of pregnancy complications, and yet the underlying molecular and cellular mechanisms of vertical transmission are poorly understood. listeria monocytogenes, a facultative intracellular pathogen, is one of a group of pathogens that are known to cause feto-placental infections in humans and other mammals. the purpose of this study was to evaluate possible mechanisms of vertical transmission of l. monocytogenes. humans and guinea pigs have a hemocho ... | 2004 | 14688130 |
| detection of bacteria in suspension by using a superconducting quantum interference device. | we demonstrate a technique for detecting magnetically labeled listeria monocytogenes and for measuring the binding rate between antibody-linked magnetic particles and bacteria. this sensitive assay quantifies specific bacteria in a sample without the need to immobilize them or wash away unbound magnetic particles. in the measurement, we add 50-nm-diameter superparamagnetic magnetite particles, coated with antibodies, to an aqueous sample containing l. monocytogenes. we apply a pulsed magnetic fi ... | 2004 | 14688406 |
| high affinity, paralog-specific recognition of the mena evh1 domain by a miniature protein. | many protein domains involved in cell signaling contain or interact with proline-rich sequences, and the design of molecules that perturb signaling pathways represents a foremost goal of chemical biology. previously we described a protein design strategy in which the well-folded alpha-helix in avian pancreatic polypeptide (app) presents short alpha-helical recognition epitopes. the miniature proteins designed in this way recognize even shallow protein clefts with high affinity and specificity. h ... | 2004 | 14709031 |
| generation and utilization of polyclonal antibodies to a synthetic c-terminal amino acid fragment of divercin v41, a class iia bacteriocin. | polyclonal antibodies have been generated by immunization of rabbits with a chemically synthesized c-terminal part of divercin v41 (dvnct) conjugated to the carrier protein keyhole limpet hemocyanin (klh). the sensitivity and reactivity of the dvnct-klh-generated antibodies were evaluated by enzyme-linked immunosorbent assay (elisa) using supernatant from cultures of 13 representative lactic acid bacterium strains, and specificity was confirmed by western blot analysis. anti-dvnct-klh antibodies ... | 2004 | 14711648 |
| a ratiometric expressible fret sensor for phosphoinositides displays a signal change in highly dynamic membrane structures in fibroblasts. | phosphoinositides are important signal transduction intermediates in cell growth, survival, and motility. we have invented a fluorescence sensor for polyphosphorylated phosphoinositides based on a peptide derived from the listeria protein acta that undergoes a random coil to helix transition upon lipid binding. the sensor, termed cay, is a fusion protein of cyan and yellow fluorescent proteins flanking the peptide at its n- and c-termini, respectively. cay displays fluorescence resonance energy ... | 2004 | 14967034 |
| detection of pcr amplicons from bacterial pathogens using microsphere agglutination. | for rapid and inexpensive detection of polymerase chain reaction (pcr) amplicons, a novel microsphere agglutination assay has been developed. pcr is carried out using biotinylated forward and reverse primers, and the amplified dna fragments are able to agglutinate streptavidin-coated microspheres (5.7 microm in diameter). purification of pcr amplicons is unnecessary when initial primer concentrations are 250 nm. agglutination can be identified visually within 2 min without any additional equipme ... | 2004 | 14967231 |
| recontamination as a source of pathogens in processed foods. | food products that have been submitted to an adequate heat-treatment during processing are free of vegetative pathogens and, depending on the treatments, of sporeformers and are generally regarded as safe. processed products such as pâté, ice cream, infant formulae and others have nevertheless been responsible for food-borne illnesses. thorough epidemiological investigations of several of these outbreaks have demonstrated that the presence of vegetative pathogens such as salmonella spp. or liste ... | 2004 | 14967555 |
| effects of chlorine and ph on efficacy of electrolyzed water for inactivating escherichia coli o157:h7 and listeria monocytogenes. | the effects of chlorine and ph on the bactericidal activity of electrolyzed (eo) water were examined against escherichia coli o157:h7 and listeria monocytogenes. the residual chlorine concentration of eo water ranged from 0.1 to 5.0 mg/l, and the ph effect was examined at ph 3.0, 5.0, and 7.0. the bactericidal activity of eo water increased with residual chlorine concentration for both pathogens, and complete inactivation was achieved at residual chlorine levels equal to or higher than 1.0 mg/l. ... | 2004 | 14967556 |
| influence of the sigb gene on the cold stress survival and subsequent recovery of two listeria monocytogenes serotypes. | the influence of serotype and the role of the sigb gene of listeria monocytogenes during the survival and recovery on different substrates were determined. wild-type and sigb mutants of two serotypes of l. monocytogenes were inoculated into buffer and onto beef steaks, and incubated at 4 degrees c for 8 weeks during which samples were removed and listeria numbers determined. growth kinetics of stationary phase wild-type and sigb mutant cells were compared, without prechilling and after prechilli ... | 2004 | 14967561 |
| inhibition of foodborne bacteria by the lactoperoxidase system in a beef cube system. | biopreservatives are being developed to inhibit the growth of foodborne pathogens and thus improve food safety. the lactoperoxidase system (lps) is a naturally occurring system that has potential for use as an antimicrobial agent in foods. growth of single strains of the pathogens staphylococcus aureus, listeria monocytogenes, escherichia coli o157:h7, salmonella enterica subsp. enterica serovar typhimurium, yersinia enterocolitica, pseudomonas aeruginosa and beef microflora were assessed on lps ... | 2004 | 14967562 |
| viability loss and morphology change of foodborne pathogens following exposure to hydrostatic pressures in the presence and absence of bacteriocins. | cell suspensions of three pathogens were exposed to hydrostatic pressure (hp), bacteriocin mixture (nisin and pediocin) or a combination of hp+bacteriocins and changes in colony forming units (cfu) and cell-morphology by scanning electron microscopy (sem) were studied. cell viability loss, as determined from the reduction in cfu before and after a treatment, occurred in listeria monocytogenes by all three treatments and in salmonella typhimurium and escherichia coli o157:h7 by hp and hp+bacterio ... | 2004 | 14967564 |
| prevalence of escherichia coli o157:h7, listeria monocytogenes, and salmonella in two geographically distant commercial beef processing plants in the united states. | for two large beef processing plants, one located in the southern united states (plant a) and one located in the northern united states (plant b), prevalence of escherichia coli o157:h7, listeria spp., listeria monocytogenes, and salmonella was determined for hide, carcass, and facility environmental samples over the course of 5 months. the prevalence of e. coli o157:h7 (68.1 versus 55.9%) and salmonella (91.8 versus 50.3%) was higher (p < 0.05), and the prevalence of listeria spp. (37.7 versus ... | 2004 | 14968961 |
| effects of cetylpyridinium chloride, acidified sodium chlorite, and potassium sorbate on populations of escherichia coli o157:h7, listeria monocytogenes, and staphylococcus aureus on fresh beef. | the effects of selected food-grade antimicrobial agents at decreasing the number of pathogenic bacteria on fresh beef were determined. beef cubes inoculated with escherichia coli o157:h7, listeria monocytogenes, or staphylococcus aureus were sprayed with 0.5% cetylpyridinium chloride (cpc), 0.12% acidified sodium chlorite (asc), 0.1% potassium sorbate (ps), or an equal mix of any two solutions. the beef samples were placed on absorbent tray pads sprayed with each single or mixed solution, wrappe ... | 2004 | 14968963 |
| changes in heat resistance resulting from ph and nutritional shifts of acid-adapted and non-acid-adapted listeria monocytogenes scott a. | stationary-phase listeria monocytogenes cells that were either ph dependent acid adapted or not acid adapted were heat challenged at 60 degrees c in a two-level full factorial design for three variables. the three variables and the levels consisted of tryptic soy broth (tsb) and sterile cell-free culture supernatant (sterile tsb), the presence and absence of 1% added glucose, and ph 4.8 and ph 7. non-acid-adapted cells were most heat resistant when challenged in tsb (mean decimal reduction times ... | 2004 | 14968964 |
| behavior of listeria monocytogenes in a pseudomonas putida biofilm on a condensate-forming surface. | listeria monocytogenes has been isolated from condensate-forming surfaces in food processing plants. the objective of this research was to observe the behavior of l. monocytogenes on condensate-covered stainless steel with a pseudomonas putida biofilm. l. monocytogenes-containing biofilms, either with or without added chicken protein, were incubated in a high humidity chamber at 12 degrees c to allow formation of condensate. samples were analyzed for attached and unattached l. monocytogenes and ... | 2004 | 14968965 |
| tracking of listeria monocytogenes in smoked fish processing plants. | four smoked fish processing plants were used as a model system to characterize listeria monocytogenes contamination patterns in ready-to-eat food production environments. each of the four plants was sampled monthly for approximately 1 year. at each sampling, four to six raw fish and four to six finished product samples were collected from corresponding lots. in addition, 12 to 14 environmental sponge samples were collected several hours after the start of production at sites selected as being li ... | 2004 | 14968966 |
| control of bacterial pathogens during processing of cold-smoked and dried salmon strips. | microbiological and chemical changes were determined during the smoking and drying of salmon strips processed at 29 to 31 degrees c for 4 days at a facility in alaska in 1993. during the process, staphylococcus aureus populations increased to more than 10(5) cfu/g after 2 to 3 days of processing. subsequent laboratory studies showed that a pellicle (dried skinlike surface) formed rapidly on the strips when there was rapid air circulation in the smokehouse and that bacteria embedded in or under t ... | 2004 | 14968968 |
| survival of listeria monocytogenes in vanilla-flavored soy and dairy products stored at 8 degrees c. | the survival of listeria monocytogenes v37 in vanilla-flavored yogurt (low-fat and nonfat) and soy milk (low-fat and plus) stored at 8 degrees c for 31 days was investigated. commercial samples of yogurt and soy milk were used. these samples were inoculated with either 10(4) or 10(7) cfu of l. monocytogenes per ml. sampling was carried out every 3 to 4 days initially and was then carried out weekly, for a total storage time of 31 days. each time a sample was collected, the ph of the sample was m ... | 2004 | 14968973 |
| biofilm formation by salmonella spp. and listeria monocytogenes on plastic surface. | to investigate the biofilm formation by 122 salmonella spp. and 48 listeria monocytogenes strains on a plastic surface. | 2004 | 15059216 |
| lack of apoptosis in listeria monocytogenes-infected thymocytes from mice fed with dietary lipids. | the potential action of certain fatty acids has been studied since the early 1970s. numerous effects on immune system functions have been related to dietary lipid administration; therefore, several of them have been applied in the treatment of inflammatory disorders. nevertheless, n-3 polyunsaturated fatty acids may affect host resistance to infectious diseases. in addition, several studies have demonstrated that certain fatty acids are involved in apoptosis induction. here, we have examined the ... | 2004 | 15060735 |
| exploitation of host cell cytoskeleton and signalling during listeria monocytogenes entry into mammalian cells. | deciphering how listeria monocytogenes exploits the host cell machinery to invade mammalian cells during infection is a key issue for the understanding how this food-borne pathogen causes a pleiotropic disease ranging from gastro-enteritis to meningitis and abortions. using multidisciplinary approaches, essentially combining bacterial genetics and cell biology, we have identified two bacterial proteins critical for entry into target cells, inla and inlb. their cellular ligands have been also ide ... | 2004 | 15060982 |
| atypical colonial morphology and low recoveries of listeria monocytogenes strains on oxford, palcam, rapid'l.mono and aloa solid media. | the performance of four commercial media, polymyxin-acriflavine-licl-ceftazidime-aesculin-mannitol (palcam), oxford, rapid'l.mono (bio-rad, marne la coquette, france) and agar listeria according to ottaviani and agosti (aloa: aes laboratoire, combourg, france; biolife, milan, italy), used to detect and enumerate 176 belgian strains of listeria monocytogenes of human and food origin, was evaluated. four strains showed a low recovery and/or atypical colonies on one or more media. these results sho ... | 2004 | 15063065 |
| simultaneous quantitative detection of listeria spp. and listeria monocytogenes using a duplex real-time pcr-based assay. | we report a duplex real-time pcr-based assay for the simultaneous quantitative detection of listeria spp. and the food-borne pathogen listeria monocytogenes. the targets of this single tube reaction were the 23s rdna and hly genes of listeria spp. and l. monocytogenes, respectively. our assay was efficient, 100% selective (i.e., it allowed accurate simultaneous identification of 52 l. monocytogenes and 120 listeria spp. strains through the fam-labelled hly and the vic-labelled 23s rdna probes, r ... | 2004 | 15063494 |
| purification and characterization of a recombinant listeriolysin o expressed in escherichia coli and possible diagnostic applications. | the secreted pore-forming toxin listeriolysin o (llo) is an essential virulence factor that allows the food-borne bacterial pathogen listeria monocytogenes to escape from the phagocytic vacuole and reach the host cytosol. this protein belongs to the group of cholesterol-binding sulfhydryl-activated toxins, expressed by a large number of gram-positive bacteria. a protocol for large-scale expression and purification of recombinant llo was previously optimized. by a simple two-step purification met ... | 2004 | 15063610 |
| negative control of listeria monocytogenes virulence genes by a diffusible autorepressor. | virulence genes from the facultative intracellular pathogen listeria monocytogenes are controlled by the transcriptional regulator prfa. although prfa synthesis is activated at 37 degrees c, prfa-dependent expression remains low in rich medium. however, a strong induction of the prfa regulon is observed when l. monocytogenes is cultured in the presence of activated charcoal. here, we show that the 'charcoal effect' results from the adsorption of a diffusible autorepressor substance released by l ... | 2004 | 15066044 |
| the htra (degp) gene of listeria monocytogenes 10403s is essential for optimal growth under stress conditions. | this report describes a mutant of listeria monocytogenes strain 10403s (serotype 1/2a) with a defective response to conditions of high osmolarity, an environment that l. monocytogenes encounters in some ready-to-eat foods. a library of l. monocytogenes clones mutagenized with tn917 was generated and scored for sensitivity to 4% nacl in order to identify genes responsible for growth or survival in elevated-nacl environments. one of the l. monocytogenes tn917 mutants, designated strain osm1, was s ... | 2004 | 15066783 |
| use of pcr-restriction fragment length polymorphism of inla for rapid screening of listeria monocytogenes strains deficient in the ability to invade caco-2 cells. | a pcr-restriction fragment length polymorphism (rflp) method was developed in order to screen a large number of strains for impaired adhesion to epithelial cells due to expression of truncated inla. inla polymorphism was analyzed by pcr-rflp in order to correlate inla pcr-rflp profiles and production of truncated inla. thirty-seven listeria monocytogenes strains isolated from various sources, including five noninvasive and two invasive reference strains, were screened. two endonucleases (alui an ... | 2004 | 15066811 |
| multilocus sequence typing of listeria monocytogenes by use of hypervariable genes reveals clonal and recombination histories of three lineages. | in an attempt to develop a method to discriminate among isolates of listeria monocytogenes, the sequences of all of the annotated genes from the fully sequenced strain l. monocytogenes egd-e (serotype 1/2a) were compared by blastn to a file of the unfinished genomic sequence of l. monocytogenes atcc 19115 (serotype 4b). approximately 7% of the matching genes demonstrated 90% or lower identity between the two strains, and the lowest observed identity was 80%. nine genes (hisj, cbie, trub, ribc, c ... | 2004 | 15066813 |
| pulsed electric field alters molecular chaperone expression and sensitizes listeria monocytogenes to heat. | pulsed electric field (pef)-resistant and pef-sensitive listeria monocytogenes strains were sublethally treated with electric pulses at 15 kv/cm for 29 micro s and held at 25 degrees c for 5 to 30 min prior to protein extraction. the levels of the molecular chaperones groel, groes, and dnaj were determined by immunoblotting. after 10 to 20 min after sublethal pef treatment, a transient decrease in molecular chaperone expression was observed in the pef-sensitive strain (scott a). the levels of gr ... | 2004 | 15066824 |
| genetic markers unique to listeria monocytogenes serotype 4b differentiate epidemic clone ii (hot dog outbreak strains) from other lineages. | a small number of closely related strains of listeria monocytogenes serotype 4b, designated epidemic clone i (eci), have been implicated in numerous outbreaks of food-borne listeriosis described during the past two decades in europe and north america. in 1998 to 1999, a multistate outbreak traced to contaminated hot dogs involved a different strain type of serotype 4b, with genetic fingerprints rarely encountered before. in spite of the profound economic and public health impact of this outbreak ... | 2004 | 15066835 |
| listeriolysin o from listeria monocytogenes is a lymphocyte apoptogenic molecule. | infection of mice with listeria monocytogenes caused marked lymphocyte apoptosis in the white pulp of the spleen on day 2 postinfection. we prove in this study that listeriolysin o (llo), a pore-forming molecule and a major virulence factor of listeria, could directly induce murine lymphocyte apoptosis both in vivo and in vitro at nanomolar and subnanomolar doses. induction of apoptosis by llo was rapid, with caspase activation seen as early as 30 min post-treatment. t cells lost their mitochond ... | 2004 | 15067065 |
| comparative analysis of gene expression among low g+c gram-positive genomes. | we present a comparative analysis of predicted highly expressed (phx) genes in the low g+c gram-positive genomes of bacillus subtilis, bacillus halodurans, listeria monocytogenes, listeria innocua, lactococcus lactis, streptococcus pyogenes, streptococcus pneumoniae, staphylococcus aureus, clostridium acetobutylicum, and clostridium perfringens. most enzymes acting in glycolysis and fermentation pathways are phx in these genomes, but not those involved in the tca cycle and respiration, suggestin ... | 2004 | 15069198 |