| a novel multiplex pcr assay for rapid and simultaneous detection of five pathogenic bacteria: escherichia coli o157:h7, salmonella, staphylococcus aureus, listeria monocytogenes, and vibrio parahaemolyticus. | rapid and sensitive detection techniques for foodborne pathogens are important to the food industry. however, traditional detection methods rely on bacterial culture in combination with biochemical tests, a process that typically takes 4 to 7 days to complete. thus, this study was conducted to address the issue of time lag inherent in traditional methods by developing a novel pcr assay for each of five foodborne pathogenic bacteria. this new system consists of a simultaneous screening method usi ... | 2007 | 17685339 |
| microbiological characterization of randomly selected portuguese raw milk cheeses with reference to food safety. | seventy raw milk cheeses made in different regions of portugal, both hard and soft varieties, made with cow's, ewe's, or goat's milk or combinations of these, were sampled within their quoted shelf lives for microbiological safety. on the basis of the presence or numbers of escherichia coli, e. coli o157, staphylococcus aureus, salmonella, and listeria monocytogenes, cheeses were categorized as satisfactory, acceptable, unsatisfactory, or unacceptable and potentially hazardous. twenty-two of the ... | 2007 | 17685347 |
| nad kinases use substrate-assisted catalysis for specific recognition of nad. | here we describe the crystal structures of the nad kinase (lmnadk1) from listeria monocytogenes in complex with its substrate nad, its product nadp, or two synthesized nad mimics. we identified one of the nad mimics, di-adenosine diphosphate, as a new substrate for lmnadk1, whereas we showed that the closely related compound di-5'-thioadenosine is a novel non-natural inhibitor for this enzyme. these structures suggest a mechanism involving substrate-assisted catalysis. indeed, sequence/structure ... | 2007 | 17686780 |
| sequencing and expression analysis of sakacin genes in lactobacillus curvatus strains. | in this study, we focused our investigation on two strains of lactobacillus curvatus, l442 and lth1174, which are able to produce bacteriocins. l. curvatus lth1174 is widely studied for its capability to produce curvacin a, while l. curvatus l442 was isolated from traditional greek fermented sausages and was shown to possess a strong inhibitory activity toward listeria monocytogenes. by polymerase chain reaction, we were able to target in both strains the genes for the production of sakacin p an ... | 2007 | 17690878 |
| explaining unexplained diarrhea and associating risks and infections. | gastrointestinal illnesses are common afflictions. however, knowledge of their etiology is often lacking. moreover, most cases of infections with reportable enteric pathogens (campylobacter jejuni, escherichia coli o157:h7, salmonella, shigella, yersinia, cryptosporidia and giardia) have sporadic modes of acquisition, yet control measures are often biased towards mitigation of risks discerned by outbreak analysis. to determine the etiology of unexplained diarrhea it is important to study populat ... | 2007 | 17692144 |
| multiplex pcr for simultaneous detection of bacteria of the genus listeria, listeria monocytogenes, and major serotypes and epidemic clones of l. monocytogenes. | a multiplex pcr assay which combines detection of bacteria of the genus listeria, listeria monocytogenes serotypes 1/2a and 4b, and epidemic clones i, ii, and iii of l. monocytogenes was developed. the assay provides a rapid, reliable, and inexpensive method for screening and subgrouping this important food-borne pathogen. | 2007 | 17693562 |
| carnobacterium: positive and negative effects in the environment and in foods. | the genus carnobacterium contains nine species, but only c. divergens and c. maltaromaticum are frequently isolated from natural environments and foods. they are tolerant to freezing/thawing and high pressure and able to grow at low temperatures, anaerobically and with increased co(2) concentrations. they metabolize arginine and various carbohydrates, including chitin, and this may improve their survival in the environment. carnobacterium divergens and c. maltaromaticum have been extensively stu ... | 2007 | 17696886 |
| regional ifngamma expression is insufficient for efficacious control of food-borne bacterial pathogens at the gut epithelial barrier. | ifngamma is critical for host defence against various food-borne pathogens including salmonella enterica and listeria monocytogenes, the causative agents of salmonellosis and listeriosis, respectively. we investigated the impact of regional ifngamma expression at the intestinal epithelial barrier on host invasion by salmonellae and listeriae following oral challenge. transgenic mice (ifngamma-gut), generated on an ifngamma knock-out (ko) background, selectively expressed ifngamma in the gut driv ... | 2007 | 17698562 |
| memory cd8+ t cells mediate antibacterial immunity via ccl3 activation of tnf/roi+ phagocytes. | cytolysis, interferon gamma and tumor necrosis factor (tnf) alpha secretion are major effector mechanisms of memory cd8+ t cells that are believed to be required for immunological protection in vivo. by using mutants of the intracellular bacterium listeria monocytogenes, we found that none of these effector activities is sufficient to protect against secondary infection with wild-type (wt) bacteria. we demonstrated that ccl3 derived from reactivated memory cd8+ t cells is required for efficient ... | 2007 | 17698589 |
| improving live attenuated bacterial carriers for vaccination and therapy. | live attenuated bacteria are well established as vaccines. thus, their use as carriers for prophylactic and therapeutic macromolecules is a logical consequence. here we describe several experimental applications of bacteria to carry heterologous macromolecules into the murine host. first, listeria monocytogenes are described that are able to transfer eukaryotic expression plasmids into host cells for gene therapy. high multiplicities of infection are still required for efficient gene transfer an ... | 2008 | 17702649 |
| changes in listeria monocytogenes membrane fluidity in response to temperature stress. | listeria monocytogenes is a food-borne pathogen that has been implicated in many outbreaks associated with ready-to-eat products. listeria adjusts to various stresses by adjusting its membrane fluidity, increasing the uptake of osmoprotectants and cryoprotectants, and activating the sigma(b) stress factor. the present work examines the regulation of membrane fluidity through direct measurement based on fluorescent anisotropy. the membrane fluidities of l. monocytogenes scott a, nr30, wt10403s, a ... | 2007 | 17704268 |
| comparative transcriptome analysis of listeria monocytogenes strains of the two major lineages reveals differences in virulence, cell wall, and stress response. | listeria monocytogenes is a food-borne, opportunistic, bacterial pathogen causing a wide spectrum of diseases, including meningitis, septicemia, abortion, and gastroenteritis, in humans and animals. among the 13 l. monocytogenes serovars described, human listeriosis is mostly associated with strains of serovars 4b, 1/2b, and 1/2a. within the species l. monocytogenes, three phylogenetic lineages are described. serovar 1/2a belongs to phylogenetic lineage i, while serovars 4b and 1/2b group in phy ... | 2007 | 17704270 |
| effect of short-term stainless steel welding fume inhalation exposure on lung inflammation, injury, and defense responses in rats. | many welders have experienced bronchitis, metal fume fever, lung function changes, and an increase in the incidence of lung infection. questions remain regarding the possible mechanisms associated with the potential pulmonary effects of welding fume exposure. the objective was to assess the early effects of stainless steel (ss) welding fume inhalation on lung injury, inflammation, and defense responses. male sprague-dawley rats were exposed to gas metal arc-ss welding fume at a concentration of ... | 2007 | 17706736 |
| examination of host immune resistance against listeria monocytogenes infection in cyclophosphamide-treated mice after dietary lipid administration. | despite the beneficial effects in the resolution of inflammatory disorders due to their immunosuppressive properties, n-3 polyunsaturated fatty acids are associated with a reduction of immune resistance to some microorganisms. here, we examine the influence of different dietary lipids on host immune resistance against listeria monocytogenes in mice treated with cyclophosphamide (cpa). | 2007 | 17707555 |
| listeria monocytogenes following orthotopic liver transplantation: central nervous system involvement and review of the literature. | listeria monocytogene is a well-recognized cause of bacteremia in immunocompromised individuals, including solid organ transplant recipients, but has been rarely reported following orthotopic liver transplantation. we describe a case of listeria meningitis that occurred within a week after liver transplantation. the patient developed a severe headache that mimicked tacrolimus encephalopathy, and was subsequently diagnosed with listeria meningitis by cerebrospinal fluid culture. the infection was ... | 2007 | 17708617 |
| classification of a moderately oxygen-tolerant isolate from baby faeces as bifidobacterium thermophilum. | bifidobacteria are found at varying prevalence in human microbiota and seem to play an important role in the human gastrointestinal tract (git). bifidobacteria are highly adapted to the human git which is reflected in the genome sequence of a bifidobacterim longum isolate. the competitiveness against other bacteria is not fully understood yet but may be related to the production of antimicrobial compounds such as bacteriocins. in a previous study, 34 bifidobacterium isolates have been isolated f ... | 2007 | 17711586 |
| occurrence of salmonella and listeria spp. on retail poultry products in south italy and comparison of conventional and rapid methods for their detection. | salmonella and listeria spp. are frequently detected in poultry meats. conventional isolation and identification methods to detect these microrganisms in food are laborious and time-consuming. in the present study the occurrence of salmonellae and listeriae on 362 samples of retail poultry in caserta, south italy was evaluated and standard microbiological and rapid methods were compared. furthermore, the samples were collected and analyzed twice a week, on monday and friday to establish their po ... | 2007 | 17713141 |
| regulation of iga production by naturally occurring tnf/inos-producing dendritic cells. | immunoglobulin-a has an irreplaceable role in the mucosal defence against infectious microbes. in human and mouse, iga-producing plasma cells comprise approximately 20% of total plasma cells of peripheral lymphoid tissues, whereas more than 80% of plasma cells produce iga in mucosa-associated lymphoid tissues (malt). one of the most biologically important and long-standing questions in immunology is why this 'biased' iga synthesis takes place in the malt but not other lymphoid organs. here we sh ... | 2007 | 17713535 |
| modelling the behaviour of listeria monocytogenes in ground pork as a function of ph, water activity, nature and concentration of organic acid salts. | to study and model the effect of sodium acetate, sodium lactate, potassium sorbate and combination of acid salts on the behaviour of listeria monocytogenes in ground pork. | 2007 | 17714386 |
| probiotic properties of lactococcus lactis ssp. lactis hv219, isolated from human vaginal secretions. | to determine the resistance of lactococcus lactis ssp. lactis hv219 to acids, bile, antibiotics, inflammatory drugs and spermicides, compare adsorption of the strain to bacteria and caco-2 cells under stress, and evaluate the antimicrobial activity of bacteriocin hv219. | 2007 | 17714396 |
| mast cells initiate early anti-listeria host defences. | the gram-positive bacterium listeria monocytogenes (l. m.) is the aetiological agent of listeriosis. the early phase listeriosis is characterized by strong innate host responses that play a major role in bacterial clearance. this is emphasized by the fact that mice deficient in t and b cells have a remarkable ability to control infection. mast cells, among the principal effectors of innate immunity, have largely been studied in the context of hyper-reactive conditions such as allergy and autoimm ... | 2008 | 17714516 |
| thermodynamically reengineering the listerial invasion complex inla/e-cadherin. | biological processes essentially all depend on the specific recognition between macromolecules and their interaction partners. although many such interactions have been characterized both structurally and biophysically, the thermodynamic effects of small atomic changes remain poorly understood. based on the crystal structure of the bacterial invasion protein internalin (inla) of listeria monocytogenes in complex with its human receptor e-cadherin (hec1), we analyzed the interface to identify sin ... | 2007 | 17715295 |
| potential of surface-enhanced raman spectroscopy for the rapid identification of escherichia coli and listeria monocytogenes cultures on silver colloidal nanoparticles. | surface-enhanced raman (sers) spectra of various batches of bacteria adsorbed on silver colloidal nanoparticles were collected to explore the potential of the sers technique for rapid and routine identification of e. coli and l. monocytogenes cultures. relative standard deviation (rsd) of sers spectra from silver colloidal suspensions and ratios of sers peaks from small molecules (k(3)po(4)) were used to evaluate the reproducibility, stability, and binding effectiveness of citrate-reduced silver ... | 2007 | 17716400 |
| rapid detection of listeria monocytogenes by nanoparticle-based immunomagnetic separation and real-time pcr. | the objective of this study was to develop a method combining nanoparticle-based immunomagnetic separation (ims) with real-time pcr for a rapid and quantitative detection of listeria monocytogenes. carboxyl modified magnetic nanoparticles were covalently bound with rabbit anti-l. monocytogenes via the amine groups. several factors, such as the amount of immunomagnetic nanoparticles (imnps), reaction and collection times, and washing step, were optimized, and the nanoparticle-based ims in combina ... | 2007 | 17716768 |
| low genetic diversity and epidemiological significance of listeria monocytogenes isolated from wild animals in the far east of russia. | the causative agent of listeriosis, a serious disease of humans and animals, listeria monocytogenes is a ubiquitous bacterium that inhabits both anthropogenic and pristine environments. we report l. monocytogenes isolation from wild animals, humans, food and the environment of a far eastern region of russia. in total, 654 samples of internal organs of small rodents belonging to the muridae and cricetidae families, and 986 samples of the liver and muscles of mollusks and fish were examined to obt ... | 2007 | 17716956 |
| in vitro inhibition activity of nisin a, nisin z, pediocin pa-1 and antibiotics against common intestinal bacteria. | to evaluate the sensitivity of 21 common intestinal bacteria to six antibiotics and three broad-spectrum bacteriocins (nisins z and a and pediocin pa-1). | 2007 | 17718835 |
| listeria as a vaccine vector. | the immunostimulatory characteristics and intracellular niche of listeria monocytogenes make it uniquely suitable for use as a live bacterial vaccine vector. preclinical results supporting this idea, and current strategies to induce beneficial cell-mediated immunity to both infectious diseases and cancer with this vector, are discussed in this review. | 2007 | 17719258 |
| innate and adaptive immune responses to listeria monocytogenes: a short overview. | the gram-positive facultative intracellular bacterium listeria monocytogenes is a model pathogen for elucidating important mechanisms of the immune response. infection of mice with a sub-lethal dose of bacteria generates highly reproducible innate and adaptive immune responses, resulting in clearance of the bacteria and resistance to subsequent l. monocytogenes infection. both the innate and adaptive immune systems are crucial to the recognition and elimination of this pathogen from the host. | 2007 | 17719259 |
| salmonella type iii-mediated heterologous antigen delivery: a versatile oral vaccination strategy to induce cellular immunity against infectious agents and tumors. | salmonella type iii secretion system (t3ss)-mediated translocation can be used for efficient delivery of heterologous antigens to the cytosol of antigen-presenting cells leading to prominent cd8 t-cell priming in orally immunized mice. the time point and duration of hybrid protein translocation during the salmonella infection cycle can be modulated by employing various type iii carrier molecules. the p60 protein of listeria monocytogenes was used as model antigen to construct chimeric ssph2/p60. ... | 2008 | 17719275 |
| establishment of procedures provoking sub-lethal injury of listeria monocytogenes, campylobacter jejuni and escherichia coli o157 to serve method performance testing. | in this study procedures provoking sub-lethal injury for three different pathogens are described which may be used in determination of accuracy and robustness of methods, comparison studies and or validation of rapid detection methods. three common food-borne pathogens were used, listeria monocytogenes, campylobacter jejuni and escherichia coli o157. the pathogens were exposed to heat stress, cold stress, freeze stress, acid stress, oxidative stress and "food" stress. sub-lethal injury was deter ... | 2007 | 17719670 |
| biodiversity of the species listeria monocytogenes and the genus listeria. | this review describes the listeria monocytogenes genome sequences available today and their comparison with that of listeria innocua and listeria welshimeri by highlighting their characteristic features and common traits. the diversity present among them is analysed with emphasis on putative virulence and host-pathogen interaction related functions. then large-scale studies comparing gene content of listeria and how these studies contributed to typing applications will be discussed. finally, evo ... | 2007 | 17719817 |
| life of listeria monocytogenes in the host cells' cytosol. | in the past decades impressive knowledge has been accumulated concerning the basic mechanisms of interactions between intracellular bacteria and their host cells. comparatively little is known on the metabolic requirements necessary for efficient replication of these bacteria within their specific host cell compartments. recent developments in functional genomics have led to more extensive studies of the metabolic aspects that may be crucial for understanding the pathogenesis of intracellular ba ... | 2007 | 17719818 |
| interference of raw milk autochthonous microbiota on the performance of conventional methodologies for listeria monocytogenes and salmonella spp. detection. | pathogen detection in foods by reliable methodologies is very important to guarantee microbiological safety. however, peculiar characteristics of certain foods, such as autochthonous microbiota, can directly influence pathogen development and detection. with the objective of verifying the performance of the official analytical methodologies for the isolation of listeria monocytogenes and salmonella in milk, different concentrations of these pathogens were inoculated in raw milk treatments with d ... | 2009 | 17720465 |
| human listeriosis and animal models. | human listeriosis is a potentially fatal foodborne infection caused by listeria monocytogenes, an opportunistic psychrophile bacterium that is widespread in the environment. it has only recently emerged as a significant cause of human infection in industrialized countries, owing to appearance of a vulnerable population of immunocompromised individuals, and the concomitant development of large-scale agro-industrial plants and refrigerated food. here we review the main clinical features of human l ... | 2007 | 17720601 |
| the epidemiology of human listeriosis. | listeriosis is a serious invasive disease that primarily afflicts pregnant women, neonates and immunocompromised adults. the causative organism, listeria monocytogenes, is primarily transmitted to humans through contaminated foods. outbreaks of listeriosis have been reported in north america, europe and japan. soft cheeses made from raw milk and ready-to-eat meats are high risk foods for susceptible individuals. efforts by food processors and food regulatory agencies to aggressively control l. m ... | 2007 | 17720602 |
| listeriolysin o: a phagosome-specific lysin. | listeriolysin o (llo) is a pore-forming toxin of the cholesterol-dependent cytolysin family and a primary virulence factor of the gram-positive, facultative intracellular pathogen listeria monocytogenes. during the intracellular life cycle of l. monocytogenes, llo is largely responsible for mediating rupture of the phagosomal membrane, thereby allowing the bacterium access to the host cytosol, its replicative niche. in the host cytosol, llo activity is controlled at numerous levels to prevent pe ... | 2007 | 17720603 |
| microarray-based characterization of the listeria monocytogenes cold regulon in log- and stationary-phase cells. | whole-genome microarray experiments were performed to define the listeria monocytogenes cold growth regulon and to identify genes differentially expressed during growth at 4 and 37 degrees c. microarray analysis using a stringent cutoff (adjusted p < 0.001; >/=2.0-fold change) revealed 105 and 170 genes that showed higher transcript levels in logarithmic- and stationary-phase cells, respectively, at 4 degrees c than in cells grown at 37 degrees c. a total of 74 and 102 genes showed lower transcr ... | 2007 | 17720827 |
| combination of immunomagnetic separation with flow cytometry for detection of listeria monocytogenes. | listeria monocytogenes can grow at the low temperature commonly used in the storage and transportation of food, and the number of cases of food poisoning caused by l. monocytogenes has increased recently in the us and europe. several methods of detecting l. monocytogenes cells have been proposed; however, all existing methods require approximately 48 h incubation. in this study, we attempted rapid detection of l. monocytogenes using flow cytometry (fcm). the method is based on measuring the numb ... | 2006 | 17723519 |
| memory phenotype cd8+ t cells with innate function selectively develop in the absence of active itk. | t cells with a memory-like phenotype and possessing innate immune function have been previously identified as cd8(+)cd44(hi) cells. these cells rapidly secrete ifn-gamma upon stimulation with il-12/il-18 and are involved in innate responses to infection with listeria monocytogenes. the signals regulating these cells are unclear. the tec kinase itk regulates t cell activation and we report here that a majority of the cd8(+) t cells in itk null mice have a phenotype of cd44(hi) similar to memory-l ... | 2007 | 17724684 |
| toward an improved laboratory definition of listeria monocytogenes virulence. | listeria monocytogenes is an opportunistic foodborne pathogen that encompasses a diversity of strains with varied virulence. the ability to rapidly determine the pathogenic potential of l. monocytogenes strains is integral to the control and prevention campaign against listeriosis. early methods for assessing l. monocytogenes virulence include in vivo bioassays and in vitro cell assays. while in vivo bioassays provide a measurement of all virulence determinants of l. monocytogenes, they are not ... | 2007 | 17727992 |
| immunization with dendritic cells loaded with alpha-galactosylceramide at priming phase, but not at boosting phase, enhances cytotoxic t lymphocyte activity against infection by intracellular bacteria. | we evaluated the effect of immunization with dendritic cells (dcs) pulsed with alpha-galactosylceramide (alphagalcer) and listeriolysin o (llo) 91-99 peptide, a dominant cytotoxic t lymphocyte (ctl) epitope of listeria monocytogenes by observing the responses of specific cd8(+) t cells and in vivo ctl activity. dcs were pulsed with various combinations of alphagalcer and llo91-99 peptide and administered to balb/c mice. immunization with dcs pulsed with alphagalcer and llo91-99 at priming phase ... | 2007 | 17760876 |
| simultaneous supratentorial and brainstem abscesses due to listeria monocytogenes. | multiple supratentorial abscesses caused by listeria monocytogenes are rare. we report the simultaneous occurrence of multiple supratentorial and brainstem abscesses due to listeria, in a patient under corticotherapy for an exacerbation of ulcerative colitis. mr imaging features before and after successful conservative treatments are depicted. in immunocompromised patients with supratentorial listerial abscesses, the coexistence of brainstem abscedation is exceptional. despite high mortality ass ... | 2008 | 17761284 |
| molecular mechanisms exploited by listeria monocytogenes during host cell invasion. | the facultative intracellular bacterial pathogen listeria monocytogenes has evolved multiple strategies to invade a large panel of mammalian cells. host cell invasion is critical for several stages of listeriosis pathology such as the initial crossing of the host intestinal barrier and the successive colonization of diverse target organs including the placenta. in this review, we address the main molecular mechanisms known to be used by l. monocytogenes during invasion of nonphagocytic cells and ... | 2007 | 17761447 |
| the prfa virulence regulon. | the prfa protein, a member of the crp/cap-fnr family of bacterial transcription factors, controls the expression of key virulence determinants of the facultative intracellular pathogen listeria monocytogenes. each of the steps of the listerial intracellular infection cycle-host cell invasion, phagosomal escape, cytosolic replication, and direct cell-to-cell spread-is mediated by products of the prfa regulon. only 10 of the 2853 genes of the l. monocytogenes egde genome have been confirmed as bon ... | 2007 | 17764998 |
| internalins: a complex family of leucine-rich repeat-containing proteins in listeria monocytogenes. | the listeria monocytogenes genome includes a large family of proteins harbouring leucine-rich repeats known as internalins (inl). the generation of novel mutants and comparative analysis of inl variability among listeria and other bacterial genomes suggest that beyond the extensively-studied invasins, inla and inlb, additional internalins also play important functions in the infectious process. | 2007 | 17764999 |
| enterococcus faecalis constitutes an unusual bacterial model in lysozyme resistance. | lysozyme is an important and widespread compound of the host constitutive defense system, and it is assumed that enterococcus faecalis is one of the few bacteria that are almost completely lysozyme resistant. on the basis of the sequence analysis of the whole genome of e. faecalis v583 strain, we identified two genes that are potentially involved in lysozyme resistance, ef_0783 and ef_1843. protein products of these two genes share significant homology with staphylococcus aureus peptidoglycan o- ... | 2007 | 17785473 |
| microbiological baseline study of swine carcasses at swedish slaughterhouses. | this 13-month survey was conducted to estimate the prevalence and counts of foodborne pathogenic bacteria and indicator bacteria on swine carcasses in sweden. a total of 541 swine carcasses were sampled by swabbing prechill at the 10 largest slaughterhouses in sweden. pathogenic yersinia enterocolitica was detected by pcr in 16% of the samples. the probability of finding y. enterocolitica increased with increasing counts of escherichia coli. no samples were positive for salmonella. the prevalenc ... | 2007 | 17803133 |
| enhancing antimicrobial activity of lysozyme against listeria monocytogenes using immunonanoparticles. | the antimicrobial efficacy of lysozyme may be reduced by undesirable interactions with food components and nontarget bacteria. immunonanoparticles, i.e., nanoparticles functionalized with pathogen-specific antibodies, may serve as an antimicrobial carrier for improving the stability and activity of antimicrobials in foods. the objective of this research was to study the antimicrobial activity of lysozyme-carrying immunonanoparticles against listeria monocytogenes. polystyrene nanoparticles with ... | 2007 | 17803140 |
| combined use of ultrasound and natural antimicrobials to inactivate listeria monocytogenes in orange juice. | the presence of listeria monocytogenes could seriously affect the safety of nonpasteurized fruit juices. high-intensity ultrasound combined with mild heat treatment and natural antimicrobials may be an alternative technology for fruit juice preservation. the response of l. monocytogenes in orange juice to combined treatments involving moderate temperature (45 degrees c), high-intensity ultrasound (600 w, 20 khz, 95.2 microm wave amplitude), and the addition of different levels of vanillin (0, 1, ... | 2007 | 17803141 |
| aerosol studies with listeria innocua and listeria monocytogenes. | aerosol studies of listeria monocytogenes in food processing plants have been limited by lack of a suitable surrogate microorganism. the objective of this study was to investigate the potential of using green fluorescent protein-labeled strains of listeria innocua as a surrogate for l. monocytogenes for aerosol studies. these studies were conducted in a laboratory bioaerosol chamber and a pilot food-processing facility. four strains of l. innocua and five strains of l. monocytogenes were used. i ... | 2007 | 17803142 |
| an 8-year surveillance of the diversity and persistence of listeria monocytogenes in a chilled food processing plant analyzed by amplified fragment length polymorphism. | contamination routes of listeria monocytogenes were examined in a chilled food processing plant that produced ready-to-eat and ready-to-reheat meals during an 8-year period by amplified fragment length polymorphism (aflp) analysis. a total of 319 l. monocytogenes isolates were recovered from raw materials (n = 18), the environment (n = 77), equipment (n = 193), and products (n = 31), and 18 different aflp types were identified, five of which were repeatedly found to be persistent types. the thre ... | 2007 | 17803143 |
| comparison of multiplex pcr with conventional biochemical methods for the identification of listeria spp. isolates from food and clinical samples in queensland, australia. | listeria monocytogenes is an important foodborne pathogen with high mortality. l. monocytogenes and five other listeria species can frequently be found in the same sample. to identify listeria isolates found in foods to the species level, two multiplex pcrs were designed. the pcr and conventional biochemical methods were compared for the identification of 456 listeria isolates collected from routine food quality monitoring schemes between june 2004 and february 2006 and for 62 l. monocytogenes i ... | 2007 | 17803144 |
| shelf life establishment of a sliced, cooked, cured meat product based on quality and safety determinants. | in the present study, the distribution of the shelf life of cooked, cured meat products based on lactic acid bacteria growth and the distribution of the time to cause health risks based on listeria monocytogenes growth were studied. growth models, developed and validated on cooked meat products, were used to predict the growth of microorganisms. temperature data were obtained from retail and home refrigerators. distribution predictions were conducted by two approaches (time-temperature profiles ... | 2007 | 17803145 |
| occurrence of listeria monocytogenes in sandwiches available to hospital patients in wales, united kingdom. | a survey for the presence of listeria monocytogenes in hospital sandwiches was carried out in wales, united kingdom, between october 2005 and march 2006. the main aim of the survey was to establish the baseline rate of l. monocytogenes in hospital sandwiches after an outbreak of listeriosis among hospital patients in 2004 was epidemiologically linked to the consumption of contaminated sandwiches. the overall positive rate found in hospital sandwiches was 2.84% for enriched culture and 0.21% for ... | 2007 | 17803157 |
| development of multilocus single strand conformation polymorphism (mlsscp) analysis of virulence genes of listeria monocytogenes and comparison with existing dna typing methods. | development of rapid and simple typing methods is required for analyzing the distribution and contamination routes of food-borne pathogens. we established a simple typing method for listeria monocytogenes using mlsscp (multilocus single strand conformation polymorphism) analysis. four virulence genes, hlya, iap, acta and inlb were amplified by pcr, digested with endonucleases and applied to gels for sscp. as banding patterns have been shown to reflect even a single nucleotide difference, this me ... | 2007 | 17822795 |
| [evaluation of the effect of lactobacillus rhamnosus probiotic culture added to yogurt over staphylococcus aureus, escherichia coli o157:h7, listeria monocytogenes and salmonella enteritidis populations]. | the effect of different types of probiotics present in yogurt over known populations of staphylococcus aureus, escherichia coli o157:h7, listeria monocytogenes and salmonella enteritidis was evaluated. the three types of yogurt used were: without added probiotics, with added probiotics (lactobacillus casei crl_431 and l. acidophilus crl_730 chr hansen) and another one with the same probiotics mentioned above and lactobacillus rhamnosus (lr-35) culture. about 10(9) cfu/ ml of each potentially pat ... | 2007 | 17824199 |
| irf3 polymorphism alters induction of interferon beta in response to listeria monocytogenes infection. | genetic makeup of the host plays a significant role in the course and outcome of infection. inbred strains of mice display a wide range of sensitivities to listeria monocytogenes infection and thus serve as a good model for analysis of the effect of genetic polymorphism. the outcome of l. monocytogenes infection in mice is influenced by the ability of this bacterium to induce expression of interferon beta mrna, encoded in mouse by the ifnb1 (interferon beta 1, fibroblast) gene. mouse strains tha ... | 2007 | 17845078 |
| antimicrobial effect of halocidin-derived peptide in a mouse model of listeria infection. | halocidin is an antimicrobial peptide found in the tunicate. a series of experiments were previously conducted in an attempt to develop a novel antibiotic derived from halocidin, as the peptide was determined to evidence profound antimicrobial activity against a variety of antibiotic-resistant microbes, with significantly less toxicity to human blood cells. in this study, we assessed the validity of one of the halocidin congeners, called khal, as a new antibiotic for the treatment of systemic ba ... | 2007 | 17846130 |
| the carboxyl-terminal sh3 domain of the mammalian adaptor crkii promotes internalization of listeria monocytogenes through activation of host phosphoinositide 3-kinase. | the intracellular bacterial pathogen listeria monocytogenes causes food-borne illnesses leading to gastroenteritis, meningitis or abortion. listeria induces its internalization into some mammalian cells through binding of the bacterial surface protein inlb to its host receptor, the met receptor tyrosine kinase. inlb-induced activation of met stimulates host signal transduction pathways that culminate in cell surface changes driving pathogen engulfment. one mammalian protein with the potential to ... | 2007 | 17848169 |
| detection of the pediocin gene peda in strains from human faeces by real-time pcr and characterization of pediococcus acidilactici uva1. | bacteriocin-producing lactic acid bacteria are commonly used as natural protective cultures. among them, strains of the genus pediococcus are particularly interesting for their ability to produce pediocin, a broad spectrum antimicrobial peptide with a strong antagonistic activity against the food-borne pathogen listeria monocytogenes. furthermore, there is increasing interest in isolating new bacteriocin-producing strains of human intestinal origin that could be developed for probiotic effects a ... | 2007 | 17850651 |
| live attenuated listeria monocytogenes expressing hiv gag: immunogenicity in rhesus monkeys. | induction of strong cellular immunity will be important for aids vaccine candidates. natural infection with wild-type listeria monocytogenes (lm), an orally transmitted organism, is known to generate strong cellular immunity, thus raising the possibility that live attenuated lm could serve as a vaccine vector. we sought to examine the potential of live attenuated lm to induce cellular immune responses to hiv gag. rhesus macaques were immunized with lmdd-gag that expresses hiv gag and lacks two g ... | 2007 | 17854955 |
| an accelerated vaccine schedule with a poly-antigenic hepatitis c virus mva-based candidate vaccine induces potent, long lasting and in vivo cross-reactive t cell responses. | we designed and evaluated in hla-class i transgenic mouse models a hepatitis c virus (hcv) t cell-based mva vectored vaccine expressing three viral antigens known to be targets of potent cd8+- and cd4+-mediated responses. an accelerated (3 week-based) vaccination induced specific cd8+ t cells harboring two effector functions (cytolytic activity - both in vitro and in vivo- and production of ifngamma) as well as specific cd4+ t cells recognizing all three vaccine antigens. responses were long las ... | 2007 | 17875349 |
| listeriolysin o is an improved protein carrier for lymphoma immunoglobulin idiotype and provides systemic protection against 38c13 lymphoma. | follicular lymphoma (fl) is a disease that responds to current treatment regimens; however, patients in general relapse with increasingly refractory disease. idiotype-based vaccines are currently under trial for the treatment of fl. these vaccines comprise the patient's bcr idiotype (id) as the tumor antigen conjugated to the protein carrier keyhole limpet hemocyanin (klh); however, other protein carriers may enhance the immune response to the lymphoma id. in this study we investigated whether a ... | 2008 | 17876582 |
| [study on molecular typing by pulsed-field gel electrophoresis of food listeria monocytogenes isolates from eight province (municipalities) of china]. | to analyse the molecular types of listeria (l.) monocytogenes, and to construct the standard china l. monocytogenes pulsed-field gel electrophoresis (pfge) subtyping database, using the international standardized l. monocytogenes-pfge protocol. | 2007 | 17877176 |
| pathogen-specific cd8 t cell responses are directly inhibited by il-10. | regulation of cd8 t cell expansion and contraction is essential for successful immune defense against intracellular pathogens. il-10 is a regulatory cytokine that can restrict t cell responses by inhibiting apc functions. il-10, however, can also have direct effects on t cells. although blockade or genetic deletion of il-10 enhances t cell-mediated resistance to infections, the extent to which il-10 limits in vivo apc function or t cell activation/proliferation remains unknown. herein, we demons ... | 2007 | 17878348 |
| early bacterial dependent induction of inducible nitric oxide synthase (inos) in epithelial cells upon transfer of cd45rb(high) cd4(+) t cells in a model for experimental colitis. | both the role of inducible nitric oxide synthase (inos) in the development of inflammatory bowel disease (ibd) as well as the molecular details governing its mucosal induction remain unclear. | 2007 | 17879278 |
| development of flexible antimicrobial films using essential oils as active agents. | the antimicrobial activity in the vapor-phase of laboratory-made flexible films of polypropylene (pp) and polyethylene/ethylene vinyl alcohol copolymer (pe/evoh) incorporating essential oil of cinnamon ( cinnamomum zeylanicum), oregano ( origanum vulgare), clove ( syzygium aromaticum), or cinnamon fortified with cinnamaldehyde was evaluated against a wide range of microorganisms: the gram-negative bacteria escherichia coli, yersinia enterocolitica, pseudomonas aeruginosa, and salmonella cholerae ... | 2007 | 17880148 |
| construction and evaluation of multisite recombinatorial (gateway) cloning vectors for gram-positive bacteria. | the gateway recombinatorial cloning system allows easy and rapid joining of dna fragments. here we report the construction and evaluation of three different gram-positive vectors that can be used with the multisite gateway cloning system to rapidly produce new gene arrangements in plasmid constructs for use in a variety of gram-positive bacteria. | 2007 | 17880697 |
| invasive pathway of listeria ivanovii in human amnion-derived wish cells. | among listeria genus, only two species, listeria ivanovii and listeria monocytogenes, are pathogenic. l. ivanovii is almost only associated with infections in animals, mainly sheep and cattle, and has rarely been associated with human infections, whereas l. monocytogenes causes severe illnesses in both humans and animals. to further investigate the pathogenetic features of l. ivanovii in humans, we undertook a study in which the intracellular behaviour of this pathogen was analysed in wish cells ... | 2007 | 17880764 |
| [influence of different types of mineral fertilizers on reproduction of listeria monocytogenes in soil]. | influence of mineral fertilizers on the reproduction of listeria monocytogenes in soil ecosystems under different temperatures (4-6 degrees c and 20-22 degrees c) was studied. application of the fertilizers favored preservation and active reproduction of l. monocytogenes in brown podzolic soil and brown forest soil. duration of application of the mineral fertilizers positively correlated with preservation and reproduction of l. monocytogenes in different types of soil. | 2007 | 17882836 |
| listeria monocytogenes meningitis: an uncommon opportunistic infection in hiv/aids. | to report an interesting case of meningitis caused by listeria monocytogenes meningitis in an hiv seropositive individual. | 2007 | 17883181 |
| prevalence and antimicrobial resistance of foodborne pathogens isolated from food products in china. | this study was undertaken to investigate the prevalence of salmonella, listeria monocytogenes, staphylococcus aureus, vibrio parahaemolyticus, and escherichia coli o157:h7 in chinese food products. the prevalence of these pathogens was 3.46%, 5.79%, 7%, 0.24%, and 0%, respectively. raw meats were mainly contaminated with salmonella (39/365, 10.7%), l. monocytogenes (26/365, 7.1%), and s. aureus (40/365, 11%), while cooked food products were mainly contaminated with l. monocytogenes (45/384, 11.7 ... | 2007 | 17883311 |
| a multiplex pcr for species- and virulence-specific determination of listeria monocytogenes. | listeria monocytogenes internalin gene inlj has been described previously for differentiation of virulent from avirulent strains. however, a recent report indicated that there exist some unusual lineage iiib strains (e.g., serotype 7 strain r2-142) that possess no inlj gene but have the capacity to cause mouse mortality via intraperitoneal inoculation. therefore, a multiplex pcr incorporating inla, inlc and inlj gene primers was developed in this study for rapid speciation and virulence determin ... | 2007 | 17884210 |
| in vitro study on bacteriocin production of enterococci associated with chickens. | in recent years, the approach of using innovative strategies such as probiotics or bacteriocins for the prevention or treatment of bacterial infections has come into focus. the present study was undertaken to check in vitro ability of enterococci-isolated from the gastrointestinal tract of chickens-to produce a bacteriocin-like substance and to describe some further probiotic properties in five selected enterococcus faecium strains. all strains (n=17) were found to produce bacteriocin-like subst ... | 2007 | 17884622 |
| limitation in the detection of listeria monocytogenes in food in the presence of competing listeria innocua. | detectability of listeria monocytogenes at 10(0) cfu per food sample in the presence of listeria innocua using standard microbiological detection was evaluated and compared with the real-time pcr-based method. | 2008 | 17887983 |
| a critical role for phospholipase c in protective immunity conferred by listeriolysin o-deficient listeria monocytogenes. | attenuated recombinant listeria monocytogenes (lm) strains are a promising class of vaccine vectors that trigger protective antigen-specific cd8 t cells. listeriolysin o (llo) is an important lm virulence determinant allowing the bacterium to escape from the endocytic vacuole into the cell cytoplasm in phagocytic cells. however in non-phagocytic cells, lm phospholipase c can also mediate cytoplasmic entry. the ability of llo-deficient lm to confer long-term protection to infection is uncertain. ... | 2008 | 17888620 |
| immunodominant tuberculosis cd8 antigens preferentially restricted by hla-b. | cd8(+) t cells are essential for host defense to intracellular bacterial pathogens such as mycobacterium tuberculosis (mtb), salmonella species, and listeria monocytogenes, yet the repertoire and dominance pattern of human cd8 antigens for these pathogens remains poorly characterized. tuberculosis (tb), the disease caused by mtb infection, remains one of the leading causes of infectious morbidity and mortality worldwide and is the most frequent opportunistic infection in individuals with hiv/aid ... | 2007 | 17892322 |
| evaluation of indirect and avidin-biotin enzyme linked immunosorbent assays for detection of anti-listeriolysin o antibodies in bovine milk samples. | listeria monocytogenes is a foodborne pathogen that causes a wide spectrum of diseases in humans and animals. enzyme linked immunosorbent assays (elisa) [indirect and avidin-biotin (a-b)] for detecting l. monocytogenes antibodies in bovine milk samples (n = 2060) were standardized and evaluated by comparison with bacteriological examination. the tests were standardized by checker board titration. highly purified listeriolysin o (llo) was used as an antigen. receiver operating characteristic (roc ... | 2007 | 17894640 |
| orally administered lactobacillus plantarum reduces pro-inflammatory interleukin secretion in sera from listeria monocytogenes infected mice. | lactic acid bacteria have traditionally been thought to have immunomodulating effects. to verify this property, lactobacillus plantarum was orally administered to mice (5 x 107 colony forming units (c.f.u.)), prior to infection with listeria monocytogenes in order to evaluate the host resistance against an infectious micro-organism and to better define the influence of l. plantarum on such responses. balb/c mice were treated daily with l. plantarum or received pbs (sham-treated mice as controls) ... | 2008 | 17894920 |
| studies probe microbes in raw milk, swine. | | 2007 | 17895451 |
| differential effect of listeria monocytogenes infection on cytokine production and cytotoxicity of cd8 t cells. | bacterial infection induces a shift to type 1 cd4 t cell subset in an infected host and this shift is important for protection of the host from disease development. many researchers think that the shift is antigen-dependent, but we previously demonstrated an initial induction step for cd4 t cell subsets during listeria monocytogenes (lm) infection is antigen-independent. although listeria is a tlr2 ligand, the immune system of the lm-infected host responded to the pathogen to induce expression o ... | 2007 | 17895607 |
| viable but non-culturable listeria monocytogenes on parsley leaves and absence of recovery to a culturable state. | to investigate the presence of viable but non-culturable listeria monocytogenes during survival on parsley leaves under low relative humidity (rh) and to evaluate the ability of l. monocytogenes to recover from vbnc to culturable state under satured humidity. | 2007 | 17897231 |
| long-term analysis of listeria monocytogenes vaginal carriage frequency in belgrade, serbia (short communication). | in order to gain insight into the frequency of l. monocytogenes vaginal carriage among women of reproductive age in belgrade, serbia, we conducted the long-term investigation (january 1992 through august 2006) described herein. the study population of 958 women included 799 patients with spontaneous abortion and 159 patients with infertility. a low rate of l. monocytogenes vaginal carriage of 0.1% was established, since only one strain was recovered from vaginal swab of a woman with spontaneous ... | 2007 | 17899798 |
| effectiveness of trisodium phosphate, acidified sodium chlorite, citric acid, and peroxyacids against pathogenic bacteria on poultry during refrigerated storage. | the effects of dipping treatments (15 min) in potable water or in solutions (wt/vol) of 12% trisodium phosphate (tsp), 1,200 ppm acidified sodium chlorite (asc), 2% citric acid (ca), and 220 ppm peroxyacids (pa) on inoculated pathogenic bacteria (listeria monocytogenes, staphylococcus aureus, bacillus cereus, salmonella enteritidis, escherichia coli, and yersinia enterocolitica) and skin ph were investigated throughout storage of chicken legs (days 0, 1, 3, and 5) at 3 +/- 1 degrees c. all chemi ... | 2007 | 17900083 |
| survival of escherichia coli o157:h7, salmonella, and listeria monocytogenes in cranberry juice concentrates at different obrix levels. | survival of escherichia coli o157:h7, salmonella, and listeria monocytogenes was evaluated in cranberry juice concentrates to determine if a 5-log reduction could be achieved without any other treatment. inactivation at 0 degrees c in concentrates with different obrix levels was determined for a five-strain composite of the individual pathogens in two physiological states. in concentrates at 18 to 46 obrix (ph 2.2 to 2.5), all three pathogens (stationary-phase or acid-adapted cells) showed at le ... | 2007 | 17900084 |
| efficacy of chlorine dioxide gas sachets for enhancing the microbiological quality and safety of blueberries. | in response to increasingly stringent microbial specifications being imposed by purchasers of frozen blueberries, chlorine dioxide (clo2) gas generated by a dry chemical sachet was assessed for inactivation of listeria monocytogenes, salmonella spp., and escherichia coli o157:h7 as well as five yeasts and molds known for blueberry spoilage. fresh blueberry samples (100 g) were separately inoculated with cocktails of l. monocytogenes, salmonella, e. coli o157:h7 (three strains each), or yeasts an ... | 2007 | 17900086 |
| performance of a growth-no growth model for listeria monocytogenes developed for mayonnaise-based salads: influence of strain variability, food matrix, inoculation level, and presence of sorbic and benzoic acid. | a previously developed growth-no growth model for listeria monocytogenes, based on nutrient broth data and describing the influence of water activity (a(w)), ph, and acetic acid concentrations, was validated (i) for a variety of l. monocytogenes strains and (ii) in a laboratory-made, mayonnaise-based surimi salad (as an example of a mayonnaise-based salad). in these challenge tests, the influence of the inoculation level was tested as well. also, the influence of chemical preservatives on the gr ... | 2007 | 17900091 |
| low temperature and binding to food components inhibit the antibacterial activity of carvacrol against listeria monocytogenes in steak tartare. | carvacrol is a major component of thyme and oregano essential oils and has potential uses as a food preservative. the effect of carvacrol on the growth of listeria monocytogenes was investigated in vitro and in steak tartare. carvacrol had strong antilisterial activity in growth medium (mic = 1.6 mm), but no effect was observed when carvacrol was tested in steak tartare. there were two reasons for this reduced activity: the antilisterial activity of carvacrol was strongly reduced at lower temper ... | 2007 | 17900092 |
| a review of the incidence and transmission of listeria monocytogenes in ready-to-eat products in retail and food service environments. | contamination of ready-to-eat products with listeria monocytogenes may occur at several stages before consumption. accessibility to the public and relatively limited control interventions at retail and food service establishments (compared with the processing sector of the food industry) and the lack of a specific regulatory framework increase the likelihood of introduction of this pathogen into some foods in these establishments. this review is a compilation of available information on the inci ... | 2007 | 17900099 |
| use of the cd107 mobilization assay reveals that cytotoxic t lymphocytes with novel mhc-ib restriction are activated during listeria monocytogenes infection. | detection of cytotoxic activity by pathogen-specific t cells of unknown antigenic specificity is difficult due to the limitations of using infected cells, instead of peptide-pulsed cells, as targets. we report here that the recently described cd107 mobilization assay readily allowed for the ex vivo detection of cytotoxic t lymphocytes (ctl) with a novel mhc-ib restriction that specifically recognized listeria monocytogenes-infected macrophages. the cd107 mobilization assay is likely to be a usef ... | 2007 | 17900608 |
| predictive modelling of the recovery of listeria monocytogenes on sliced cooked ham after high pressure processing. | this study examined bacterial recovery on sliced cooked ham that was inoculated with listeria monocytogenes, treated by high pressure processing (hpp) and then stored at 10 degrees c for 70 days. the number of l. monocytogenes on the ham inoculated with 5 log(10) cfu/g was initially reduced by hpp at 500 mpa for 10 min to below the detectable level (10 cfu/g). however, the bacterial count gradually increased during storage, and exceeded the initial inoculum level at the end of the 70-day period, ... | 2007 | 17900728 |
| [rhombencephalitis due to listeria monocytogenes]. | a 37-year-old man presented with acute dizziness, nausea, headache and fever. later on, he developed diplopia, swallowing difficulties, numbness and ataxia. mri on day 6 showed hypo-intense, contrast-enhancing lesions on ti-weighted scans in the brainstem and cerebellum. cerebrospinal fluid (csf) findings on day 6 included pleiocytosis, a mildly-elevated protein level and mildly-decreased glucose level. csf and blood cultures were initially negative for both bacteria and viruses. acute dissemina ... | 2007 | 17902563 |
| the effect of disease activity on leptin, leptin receptor and suppressor of cytokine signalling-3 expression in relapsing-remitting multiple sclerosis. | in this study we observed higher serum leptin levels in relapsing-remitting multiple sclerosis (rrms) patients during remission than in controls. the expression of leptin receptor (obr) was higher in cd8+ t cells and monocytes from rrms patients in relapse than in patients in remission and in controls. relapsing patients showed high levels of pstat3 and low expression of socs3 and leptin administration induced an up-regulation of pstat3 only in monocytes from patients in relapse. our data sugges ... | 2007 | 17904647 |
| improving gastric transit, gastrointestinal persistence and therapeutic efficacy of the probiotic strain bifidobacterium breve ucc2003. | given the increasing commercial and clinical relevance of probiotic cultures, improving their stress tolerance profile and ability to overcome the physiological defences of the host is an important biological goal. in order to reach the gastrointestinal tract in sufficient numbers to exert a therapeutic effect, probiotic bacteria must resist the deleterious actions of low ph, elevated osmolarity and bile salts. cloning the listerial betaine uptake system, betl, into the probiotic strain bifidoba ... | 2007 | 17906153 |
| the heat-shock response of listeria monocytogenes comprises genes involved in heat shock, cell division, cell wall synthesis, and the sos response. | the food-borne pathogen listeria monocytogenes has the ability to survive extreme environmental conditions due to an extensive interacting network of stress responses. it is able to grow and survive at relatively high temperatures in comparison with other non-sporulating food-borne pathogens. to investigate the heat-shock response of l. monocytogenes, whole-genome expression profiles of cells that were grown at 37 degrees c and exposed to 48 degrees c were examined using dna microarrays. transcr ... | 2007 | 17906156 |
| antibacterial activity of a bacteriocin-like substance produced by bacillus sp. p34 that targets the bacterial cell envelope. | the objective of this study was to investigate the mode of action of bls p34, a bacteriocin-like substance (bls) produced by a novel bacillus sp. strain p34 isolated from the amazon basin. the effect of the bls was tested against listeria monocytogenes, showing a bactericidal effect at 200 au (activity units) ml(-1), while no inhibition of spore outgrowth of bacillus cereus was observed with a dose of 1,600 au ml(-1). growth of escherichia coli and salmonella enteritidis was inhibited, but only ... | 2008 | 17906937 |
| lpla1-dependent utilization of host lipoyl peptides enables listeria cytosolic growth and virulence. | the bacterial pathogen listeria monocytogenes replicates within the cytosol of mammalian cells. mechanisms by which the bacterium exploits the host cytosolic environment for essential nutrients are poorly defined. l. monocytogenes is a lipoate auxotroph and must scavenge this critical cofactor, using lipoate ligases to facilitate attachment of the lipoyl moiety to metabolic enzyme complexes. although the l. monocytogenes genome encodes two putative lipoate ligases, lpla1 and lpla2, intracellular ... | 2007 | 17908209 |
| conjugal transfer of plasmid r6k gamma ori minireplicon derivatives from escherichia coli to various genera of pathogenic bacteria. | three r6k-derived gamma ori minireplicons were successfully transferred by conjugation from escherichia coli to several species of pathogenic bacteria. the pfl129 replicon encodes the wild-type initiation replication protein pi, while plasmids pfl130 and pag101 encode mutant forms of the pi protein conferring the plasmid copy-up phenotype. plasmids could be transferred to all recipient species tested, although high efficiency conjugal transfer was only obtained with genera of the enterobacteriac ... | 2007 | 17909888 |
| the effect of micro-architectural structure of cabbage substratum and or background bacterial flora on the growth of listeria monocytogenes. | the effect of micro-architectural structure of cabbage (brassica oleracea var. capitata l.) substratum and or background bacterial flora on the growth of listeria monocytogenes as a function of incubation temperature was investigated. a cocktail mixture of pseudomonas fluorescens, pantoea agglomerans and lactobacillus plantarum was constituted to a population density of approximately 5 log cfu/ml in order to pseudo-simulate background bacterial flora of fresh-cut cabbage. this mixture was co-ino ... | 2007 | 17910986 |
| the c/ebp beta isoform 34-kda lap is responsible for nf-il-6-mediated gene induction in activated macrophages, but is not essential for intracellular bacteria killing. | the c/ebpb gene is translated into three different protein isoforms, two transcriptional activating proteins (38-kda full and 34-kda liver-enriched transcriptional activation protein (lap)) and one transcriptional inhibitory protein, by alternative use of different aug initiation codons within the same open reading frame. the isoform 34-kda lap is thought to be the most transcriptionally active form of c/ebpbeta in macrophages. to assess the function of the 34-kda lap in vivo, we generated knock ... | 2007 | 17911624 |