Publications

good visual outcome after listeria monocytogenes endogenous endophthalmitis.		1999	10606462
from the centers for disease control and prevention. update: multistate outbreak of listeriosis--united states, 1998-1999.		1999	9929073
cytokines are critical in linking the innate and adaptive immune responses to bacterial, fungal, and parasitic infection.		1999	9929716
cytotoxic t-cell, delayed type hypersensitive and listeriolysin o responses in experimental bovine listeriosis.	five different antigens of listeria monocytogenes nctc 11994 were assayed for their lymphoproliferative, cytotoxic, humoral and delayed type hypersensitivity (dth) responses in experimentally infected calves. the antigens used were culture filtrate antigen (cfa), listeriolysin o (llo), sonicated antigen (sa), live antigen (la) and heat killed antigen (hka). cfa was most lymphoproliferative when assayed in vitro. in an autologous monocyte cytotoxicity assay, soluble protein as well as bacterial c ...	1999	10063538
inhibition of listeria monocytogenes in cottage cheese manufactured with a lacticin 3147-producing starter culture.	the efficacy of using a lacticin 3147-producing starter as a protective culture to improve the safety of cottage cheese was investigated. this involved the manufacture of cottage cheese using lactococcus lactis dpc4268 (control) and l. lactis dpc4275, a bacteriocin-producing transconjugant strain derived from dpc4268. a number of listeria monocytogenes strains, including a number of industrial isolates, were assayed for their sensitivity to lacticin 3147. these strains varied considerably with r ...	1999	10063625
the resistance against listeria monocytogenes and the formation of germinal centers depend on a functional death domain of the 55 kda tumor necrosis factor receptor.	the biological functions mediated by the death domain of the 55-kda tumor necrosis factor receptor (tnfrp55) in vivo are still elusive. tnfrp55 mutants lacking a functional death domain were expressed in tnfrp55-/- and in tnfrp55+/- mice as transgenes under control of the h-2kb promoter. analysis of these animals revealed that signals originating from the tnfrp55 death domain are indispensable for the protection against listeria monocytogenes, the expression of mucosal addressin cell adhesion mo ...	1999	10064074
impact of intracellular location of and antigen display by intracellular bacteria: implications for vaccine development.	intracellular bacteria are primarily controlled by t-lymphocytes. the 'phagosomal' bacteria such as salmonella enterica and mycobacterium bovis bcg remain in the phagosome. these microbes primarily stimulate cd4 t-cells via antigen presentation through mhc class ii molecules. in contrast, listeria monocytogenes egresses from the phagosome into the cytoplasm by virtue of listeriolysin. this 'cytoplasmic' pathogen is controlled by cd8 t-cells through mhc class i antigen presentation. some bacteria ...	1999	10065631
t lymphocyte dynamics during listeria monocytogenes infection.	infection of mice with listeria monocytogenes results in a robust t lymphocyte response that clears the pathogen and provides long term immunity from reinfection. the number of splenic cd4+ and cd8+ t cells and natural killer cells increases during primary and recall infection with l. monocytogenes, however the proportional increase is greatest for cd8+ t cells. the proportion of cd8 t cells expressing low levels of cd62l, a sign of activation, was increased among immune splenocytes, suggesting ...	1999	10065633
dietary omega-3 polyunsaturated fatty acids from fish oil reduce interleukin-12 and interferon-gamma production in mice.	the objective of this study was to investigate the impact of feeding mice a diet rich in n-3 polyunsaturated fatty acids (pufa) from fish oil on the interleukin-12 (il-12) and interferon-gamma (ifngamma) production during the early stage of an infectious challenge with listeria monocytogenes. weanling female c3h/hen mice were fed ain-93g experimental diets containing 20%, by weight one of three fat sources: lard (low pufa), soybean oil (n-6 pufa) or a mixture (9:1) of menhaden fish oil and corn ...	1999	10065739
[fulminant sepsis by listeria monocytogenes in a patient with coinfection by human immunodeficiency virus].		1999	10217855
motility of acta protein-coated microspheres driven by actin polymerization.	actin polymerization is required for the generation of motile force at the leading edge of both lamellipodia and filopodia and also at the surface of motile intracellular bacterial pathogens such as listeria monocytogenes. local catalysis of actin filament polymerization is accomplished in l. monocytogenes by the bacterial protein acta. polystyrene beads coated with purified acta protein can undergo directional movement in an actin-rich cytoplasmic extract. thus, the actin polymerization-based m ...	1999	10220392
molecular cloning and phylogenetic analysis of the small cytoplasmic rna from listeria monocytogenes.	a molecular cloning strategy has been designed to isolate the gene that encodes the small cytoplasmic rna (scrna) component of bacterial signal recognition particles. using this strategy a putative listeria monocytogenes scrna lambda gt11 recombinant clone was isolated. a previously described complementation assay developed to genetically select functional homologues of 4.5s rna and scrna of bacteria confirmed that the lambda gt11 recombinant clone isolated encoded for the scrna from l. monocyto ...	1999	10220880
il-12 is dispensable for innate and adaptive immunity against low doses of listeria monocytogenes.	we have studied il-12p35-deficient (il-12p35(-/-)) mice to evaluate the role of il-12 in resistance against listeria monocytogenes. in the absence of bioactive il-12p75, mutant mice acquired higher bacterial organ burden than wild-type mice and died during the first week following infection with normally sublethal doses of listeria. moreover, blood ifn-gamma levels were strikingly reduced in mutant mice at day 2 post-infection. these results suggest that in il-12p35-deficient mice impaired produ ...	1999	10221644
effector cells of both nonhemopoietic and hemopoietic origin are required for interferon (ifn)-gamma- and tumor necrosis factor (tnf)-alpha-dependent host resistance to the intracellular pathogen, toxoplasma gondii.	although interferon (ifn)-gamma-activated, mononuclear phagocytes are considered to be the major effectors of resistance to intracellular pathogens, it is unclear how they control the growth of microorganisms that reside in nonhemopoietic cells. pathogens within such cells may be killed by metabolites secreted by activated macrophages or, alternatively, directly controlled by cytokine-induced microbicidal mechanisms triggered within infected nonphagocytic cells. to distinguish between these two ...	1999	10190899
cpg-containing oligonucleotides are efficient adjuvants for induction of protective antiviral immune responses with t-cell peptide vaccines.	synthetic nonmethylated oligonucleotides containing cpg dinucleotides (cpg-odns) have been shown to exhibit immunostimulatory activity. cpg-odns have the capacity to directly activate b cells, macrophages, and dendritic cells, and we show here that this is reflected by cell surface binding of oligonucleotides to these cell subsets. however, t cells are not directly activated by cpg-odns, which correlates with the failure to bind to the t-cell surface. efficient competition for cpg-induced b-cell ...	1999	10196308
effect of elevated oxygen and carbon dioxide on the surface growth of vegetable-associated micro-organisms.	the impact of a novel type of modified atmosphere (ma), referred to as high o2-ma, on micro-organisms associated with the spoilage of minimally-processed vegetables was studied. pure cultures of pseudomonas fluorescens, enterobacter agglomerans, aureobacterium strain 27, candida guilliermondii, c. sake, salmonella typhimurium, salm. enteritidis, escherichia coli, listeria monocytogenes, leuconostoc mesenteroides var. mesenteroides, lactobacillus plantarum and lactococcus lactis were cultured on ...	1999	10196748
effect of osmotic, alkaline, acid or thermal stresses on the growth and inhibition of listeria monocytogenes.	five strains of listeria monocytogenes (a, b, c, d and e) isolated from industrial plants have been subjected to different osmotic, alkaline, acid or thermal stresses. the effects of these treatments on lag-phase (l) and growth rate (mu) of cells in mid-log phase have been followed using an automated optical density monitoring system. increasing the osmotic pressure by the addition of different amounts of nacl increased the lag phase and decreased the growth rate. the same phenomena were observe ...	1999	10196752
response to high-pressure, low-temperature treatment in vegetables: determination of survival rates of microbial populations using flow cytometry and detection of peroxidase activity using confocal microscopy.	application of high hydrostatic pressure (200, 300, 350 and 400 mpa) at 5 degrees c for 30 min to different micro-organisms, including gram-positive and gram-negative bacteria, moulds and yeasts, proved to be more effective in inactivating these organisms than treatments at 20 degrees c for 10 min and at 10 degrees c for 20 min. moulds, yeasts, gram-negative bacteria and listeria monocytogenes were most sensitive, and their populations were completely inactivated at pressures between 300 and 350 ...	1999	10196760
behaviour of listeria monocytogenes under combined chilling processes.	the behaviour of listeria monocytogenes under chilling processes was investigated. growth kinetics were measured at 7 degrees c in tsbye culture medium as a function of ph (7.2 and 6.2), pre-incubation temperatures (4 or 7 degrees c), cooling (0.05 or 0.1 degree c min-1) and freezing (0 and -5 degrees c) treatments. growth curves generated were fitted by gompertz and baranyi functions. the baranyi function gave better parameter estimation values than the gompertz equation which over-estimated th ...	1999	10196772
biopreservation in modified atmosphere stored mungbean sprouts: the use of vegetable-associated bacteriocinogenic lactic acid bacteria to control the growth of listeria monocytogenes.	two bacteriocinogenic strains of pediococcus parvulus and one bacteriocinogenic enterococcus mundtii strain were evaluated for their potential to control the growth of listeria monocytogenes on refrigerated, modified atmosphere (ma) stored mungbean sprouts. these three strains, which were isolated from minimally-processed vegetables, were shown to grow in culture broth at 4, 8, 15 and 30 degrees c. however, only ent. mundtii was capable of bacteriocin production at 4-8 degrees c. examination of ...	1999	10196774
the origin and function of soluble cd14 in experimental bacterial meningitis.	murine experimental meningitis models induced by either escherichia coli lps, live streptococcus pneumoniae, or listeria monocytogenes were used to study the origin and potential function of soluble cd14 (scd14) in the brain during bacterial meningitis. whereas intracerebral infection caused only a minor and/or transient increase of scd14 levels in the serum, dramatically elevated concentrations of scd14 were detected in the cerebrospinal fluid. reverse-transcriptase pcr and facs analysis of the ...	1999	10202018
enhancement of the listeria monocytogenes p60-specific cd4 and cd8 t cell memory by nonpathogenic listeria innocua.	the contact of t cells to cross-reactive antigenic determinants expressed by nonpathogenic environmental micro-organisms may contribute to the induction or maintenance of t cell memory. this hypothesis was evaluated in the model of murine listeria monocytogenes infection. the influence of nonpathogenic l. innocua on the l. monocytogenes p60-specific t cell response was analyzed. we show that some cd4 t cell clones raised against purified p60 from l. monocytogenes cross-react with p60 purified fr ...	1999	10202020
increased expression of rab5a correlates directly with accelerated maturation of listeria monocytogenes phagosomes.	previous studies have shown that listeria monocytogenes (lm) modulates phagocytic membrane traffic. here we explore whether rab5a, a gtpase associated with phagosome-endosome fusion, is related to phagosome maturation and to the intracellular survival of lm. stable transfection of rab5a cdna into macrophages accelerates intracellular degradation of lm. morphological studies confirmed that phagosome maturation and phagosome-lysosome fusion is enhanced by overexpression of rab5a. down-regulation e ...	1999	10206948
rapid detection of listeria monocytogenes by a pcr assay specific for an aminopeptidase.	specific and rapid detection of listeria monocytogenes is very important with regard to food safety since all other species of listeria appear to be non-pathogenic to humans. conventional microbiological detection methods are very time consuming. the polymerase chain reaction (pcr) is one of the most promising techniques for rapid detection of micro-organisms in food products. we have developed a pcr assay, specific for l. monocytogenes, based on the gene encoding an aminopeptidase, which previo ...	1999	10208803
delivery of protein to the cytosol of macrophages using escherichia coli k-12.	listeriolysin o (llo) is an essential determinant of pathogenicity whose natural biological role is to mediate lysis of listeria monocytogenes containing phagosomes. in this study, we report that escherichia coli expressing cytoplasmic recombinant llo can efficiently deliver co-expressed proteins to the cytosol of macrophages. we propose a model in which subsequent or concomitant to phagocytosis the e. coli are killed and degraded within phagosomes causing the release of llo and target proteins ...	1999	10209738
listeriolysin o-dependent activation of endothelial cells during infection with listeria monocytogenes: activation of nf-kappa b and upregulation of adhesion molecules and chemokines.	the facultative intracellular bacterium listeria monocytogenes is an invasive pathogen that crosses the vascular endothelium and disseminates to the placenta and the central nervous system. its interaction with endothelial cells is crucial for the pathogenesis of listeriosis. by infecting in vitro human umbilical vein endothelial cells (huvec) with l. monocytogenes, we found that wild-type bacteria induced the expression of the adhesion molecules (icam-1 and e-selectin), chemokine secretion (il- ...	1999	10209744
in vitro efficacy of n-duopropenide, a recently developed disinfectant containing quaternary ammonium compounds, against selected gram-positive and gram-negative organisms.	to study the efficacy of n-duopropenide against various gram-positive and gram-negative organisms.	1999	10211693
adherence of listeria monocytogenes strains to stainless steel coupons.	an assay was developed to measure the number of listeria monocytogenes cells adhering to stainless steel, and was used to investigate the adherence of 111 strains of the organism, which included representatives with respect to serotype, carriage of plasmids, source and persistence in the food processing environment. growth and adherence curves of four l. monocytogenes strains over 48 h were obtained. while the growth curves of all four micro-organisms were seen to reach similar levels at station ...	1999	10212403
response surface methodology, an approach to predict the effects of a lactoperoxidase system, nisin, alone or in combination, on listeria monocytogenes in skim milk.	experimental designs using response surface methodology (rsm) were used to determine effects and interactions of nisin (0-200 i.u. ml-1), ph values (5.4-6.6), incubation time (0-36 h or 0-144 h) and the lactoperoxidase-thiocyanate-hydrogen peroxide system (lps) on listeria monocytogenes cip 82110 in skim milk, at 25 degrees c. the lps varied from level 0-2; lps at level 1 consisted of lactoperoxidase (35 mg l-1), thiocyanate (25 mg l-1) and h2o2, which was supplied exogenously by glucose-oxidase ...	1999	10212409
development and evaluation of a 24 well microtitre plate method for isolation of listeria spp. or listeria monocytogenes from foods.	a rapid and simple method (24m) using 24 well microtitre plates was developed to determine the presence of listeria monocytogenes or listeria spp. in food samples. the 24m was composed of two 24 well microtitre plates connected with a yellow tip. the 24m was evaluated with pathogen cocktails and ground beef samples and compared with the conventional method for presumptive identification of listeria spp. only food-borne pathogen cocktails and ground beef samples containing l. monocytogenes or lis ...	1999	10212440
high pressure response of fruit jams contaminated with listeria monocytogenes.	high pressure is an alternative to thermal processing and is used to preserve food. listeria monocytogenes is a bacterium which grows at low temperature, is able to multiply under vacuum, and is responsible for food poisoning. pressures of 100, 200, 300 and 400 mpa were used for 5, 10 and 15 min at 20 degrees c on pure culture, and on apple and plum jam baby food artificially contaminated with listeria. pure culture was also to test pressures of 200, 300, 350 and 400 mpa at 5 degrees c for 30 mi ...	1999	10212445
antiorthostatic suspension stimulates profiles of macrophage activation in mice.	the antiorthostatic suspension model simulates certain physiological effects of spaceflight. we have previously reported bdf1 mice suspended by the tail in the antiorthostatic orientation for 4 days express high levels of resistance to virulent listeria monocytogenesinfection. in the present study, we examined whether the increased resistance to this organism correlates with profiles of macrophage activation, given the role of the macrophage in killing this pathogen in vivo. we infected bdf1 mic ...	1999	10213913
mechanism of the intracellular killing and modulation of antibiotic susceptibility of listeria monocytogenes in thp-1 macrophages activated by gamma interferon.	listeria monocytogenes, a facultative intracellular pathogen, readily enters cells and multiplies in the cytosol after escaping from phagosomal vacuoles. macrophages exposed to gamma interferon, one of the main cellular host defenses against listeria, become nonpermissive for bacterial growth while containing listeria in the phagosomes. using the human myelomonocytic cell line thp-1, we show that the combination of l-monomethyl arginine and catalase restores bacterial growth without affecting th ...	1999	10223943
division of listeria monocytogenes serovar 1/2a strains into two groups by pcr and restriction enzyme analysis.	altogether, 100 strains of listeria monocytogenes serovar 1/2a isolated from humans, animals, food, and the environment were typed by a combination of pcr and restriction enzyme analysis (rea). a pcr product of 2,916 bp, containing the downstream end of the gene inla (955 bp), the space between inla and inlb (85 bp), and 1,876 bp of the gene inlb, was cleaved with the enzyme alui, and the fragments generated were separated by gel electrophoresis. by this method two different cleavage patterns we ...	1999	10224000
identification and disruption of betl, a secondary glycine betaine transport system linked to the salt tolerance of listeria monocytogenes lo28.	the trimethylammonium compound glycine betaine (n,n, n-trimethylglycine) can be accumulated to high intracellular concentrations, conferring enhanced osmo- and cryotolerance upon listeria monocytogenes. we report the identification of betl, a gene encoding a glycine betaine uptake system in l. monocytogenes, isolated by functional complementation of the betaine uptake mutant escherichia coli mkh13. the betl gene is preceded by a consensus sigmab-dependent promoter and is predicted to encode a 55 ...	1999	10224004
mutational analysis of the role of hpr in listeria monocytogenes.	the regulatory role of hpr, a protein of the phosphotransferase system (pts), was investigated in listeria monocytogenes. by constructing mutations in the conserved histidine 15 and serine 46 residues of hpr, we were able to examine how hpr regulates pts activity. the results indicated that histidine 15 was phosphorylated in a phosphoenolpyruvate (pep)-dependent manner and was essential for pts activity. serine 46 was phosphorylated in an atp-dependent manner by a membrane-associated kinase. atp ...	1999	10224008
detection of viable listeria monocytogenes with a 5' nuclease pcr assay.	a 5' nuclease assay has been developed to detect viable listeria monocytogenes. the assay targets the hemolysin a (hlya) transcript, which is found only in l. monocytogenes. the single-tube, reverse transcriptase (rt), fluorogenic probe-based assay was formatted by using tth dna polymerase whose activity was modulated by using the manganese-chelating morpholinepropanesulfonic acid (mops) buffer. this assay was quantitative over a 3-log-unit range of template concentrations when tested with an in ...	1999	10224010
detection of salmonella spp. and listeria monocytogenes in suspended organic waste by nucleic acid extraction and pcr.	a nucleic acid-based method for the detection of the bacterial pathogens salmonella spp. and listeria monocytogenes in biological waste was developed. the detection limits were less than 10 cells per ml of biological waste. the method does not include a phenol extraction step and can be easily performed in 1 to 2 days.	1999	10224026
cd8+ t cells are a biologically relevant source of macrophage inflammatory protein-1 alpha in vivo.	chemokines are small proteins that direct the migration of leukocytes to inflammatory foci. many cell types, including macrophages, fibroblasts, endothelial cells, and lymphocytes, produce chemokines in vitro, but biologically relevant sources of chemokines in vivo have not been well characterized. to investigate the pertinent sources of macrophage inflammatory protein-1 alpha (mip-1 alpha) in vivo, we used mip-1 alpha-deficient (mip-1 alpha-/-) mice as donors and as recipients in adoptive trans ...	1999	10228020
response to listeria monocytogenes in mice lacking mhc class ia molecules.	mhc class ia-deficient mice (h2 kb-/- db-/-) inoculated with the intracellular pathogen listeria monocytogenes (lm) displayed a three- to fourfold expansion of splenic cd8+ t cells 6 days following infection. culture of these spleen cells in vitro gave rise to ctl that recognized lm-infected target cells and were restricted by the class ib molecules, qa1b and m3. exposure of target cells to heat-killed lm (hklm) rather than live bacteria did not result in ctl-mediated lysis. target cells pulsed ...	1999	10228021
listeria monocytogenes-induced endogenous endophthalmitis in an otherwise healthy individual: rapid pcr-diagnosis as the basis for effective treatment.	listeria monocytogenes is a rare cause of endogenous endophthalmitis. to date 15 cases have been published in the literature. all eyes showed similar clinical features and profound visual loss mainly due to delayed diagnosis.	1999	10230593
the protective role of t-cell receptor vgamma1+ t cells in primary infection with listeria monocytogenes.	we have previously reported that the t-cell receptor (tcr) gamma delta+ t cells increase in mice infected with an intracellular bacteria listeria monocytogenes, and the cells predominantly express vdelta6 and vgamma1 genes. in this study, we used a monoclonal antibody (mab) specific to tcr vgamma1 to estimate the frequency of vgamma1+ t cells and we discuss their significance in protection against l. monocytogenes. the spleen, liver and peritoneal exudate cells from mice intraperitoneally infect ...	1999	10233675
characterisation of a new operon encoding a zur-like protein and an associated abc zinc permease in listeria monocytogenes.	metal ions uptake is mainly studied for iron, as it has often been implicated in bacterial virulence. although listeria monocytogenes virulence is expected to be controlled by the iron availability, little is known about such an uptake and its regulation. we describe the analysis of the first operon involved in metal ions uptake in l. monocytogenes. its three orfs encode respectively (1) an abc protein, likely implicated in zinc uptake, (2) a hydrophobic membrane protein, generally associated wi ...	1999	10234828
characteristics of induction of virulence factor expression by activated charcoal in listeria monocytogenes.	activated charcoal has been previously shown to induce in vitro expression of virulence factors by listeria monocytogenes. in trying to elucidate the nature of the charcoal action, we found that the treatment of brain heart infusion medium with activated charcoal followed by charcoal removal does not result in an increase of virulence factor expression. at the same time, the addition of fresh charcoal to the charcoal-treated medium induces expression, suggesting that the effect of activated char ...	1999	10234832
a comparative study of the actin-based motilities of the pathogenic bacteria listeria monocytogenes, shigella flexneri and rickettsia conorii.	listeria monocytogenes, shigella flexneri, and rickettsia conorii are three bacterial pathogens that are able to polymerize actin into 'comet tail' structures and move within the cytosol of infected cells. the actin-based motilities of l. monocytogenes and s. flexneri are known to require the bacterial proteins acta and icsa, respectively, and several mammalian cytoskeleton proteins including the arp2/3 complex and vasp (vasodilator-stimulated phosphoprotein) for l. monocytogenes and vinculin an ...	1999	10318762
clpe, a novel type of hsp100 atpase, is part of the ctsr heat shock regulon of bacillus subtilis.	clp atpases, which include the ubiquitous hsp100 family, are classified according to their structural features and sequence similarities. during the course of the bacillus subtilis genome sequencing project, we identified a gene encoding a new member of the hsp100 family. we designated this protein clpe, as it is the prototype of a novel subfamily among the clp atpases, and have identified homologues in several bacteria, including listeria monocytogenes, enterococcus faecalis, streptococcus pyog ...	1999	10320580
peptidoglycan hydrolase lytf plays a role in cell separation with cwlf during vegetative growth of bacillus subtilis.	peptidoglycan hydrolase, lytf (cwle), was determined to be identical to yhdd (deduced cell wall binding protein) by zymography after insertional inactivation of the yhdd gene. yhdd exhibits high sequence similarity with cwlf (papq, lyte) and p60 of listeria monocytogenes. the n-terminal region of yhdd has a signal sequence followed by five tandem repeated regions containing polyserine residues. the c-terminal region corresponds to the catalytic domain, because a truncated protein without the n-t ...	1999	10322020
actin and phosphoinositide binding by the acta protein of the bacterial pathogen listeria monocytogenes.	the surface protein acta of the pathogenic bacterium listeria monocytogenes induces actin-driven movement of bacteria in the cytoplasm of infected host cells and serves as a model for actin-based motility in general. we generated and purified soluble recombinant fragments of acta and assessed their ability to interact with the acidic phospholipids phosphatidylinositol 4,5-bisphosphate and phosphatidylinositol 3,4,5-trisphosphate, both implicated in the regulation of actin polymerization. purifie ...	1999	10559250
spatial control of actin polymerization during neutrophil chemotaxis.	neutrophils respond to chemotactic stimuli by increasing the nucleation and polymerization of actin filaments, but the location and regulation of these processes are not well understood. here, using a permeabilized-cell assay, we show that chemotactic stimuli cause neutrophils to organize many discrete sites of actin polymerization, the distribution of which is biased by external chemotactic gradients. furthermore, the arp2/3 complex, which can nucleate actin polymerization, dynamically redistri ...	1999	10559877
rocket-based motility: a universal mechanism?		1999	10559888
[study of mechanism of the pathogenic bacteria adaptation to the environmental factors].		1999	10560060
autotrophic assimilation of co2 and c1-compounds by pathogenic bacteria.	we demonstrate for the first time that the pathogenic bacteria yersinia pseudotuberculosis and listeria monocytogenes (pathogens of saprozoonoses) are capable of chemolithoautotrophic assimilation of co2. low temperature is favorable for better absorption of co2 by these bacteria; this is supported by increased enzymatic activity of carbonic anhydrase acting as the supplier of the substrate to the site of carboxylation. data of radioisotopic methods indicate that assimilated labeled carbon of co ...	1999	10561561
host cell signal transduction during listeria monocytogenes infection.	the facultative intracellular bacterial pathogen listeria monocytogenes invades and multiplies in many mammalian cell types. during the interaction with its host cells it strongly interferes with and modulates host cell functions. in the present review we summarize the current knowledge on the modulation of signal transduction pathways by secreted listerial products prior to bacterium-cell contact, during uptake, or while l. monocytogenes resides in the different intracellular compartments.	1999	10562430
prfa, the transcriptional activator of virulence genes, is upregulated during interaction of listeria monocytogenes with mammalian cells and in eukaryotic cell extracts.	most virulence genes of listeria monocytogenes are activated by the transcriptional regulator prfa. previous studies have shown that environmental parameters, such as temperature, ph, stress conditions and medium composition, affect the expression of prfa and prfa-dependent proteins. in this report, we demonstrate a threefold increase in prfa protein synthesis during infection of mammalian cells, which correlates with the increased activity of the plca promoter, the major prfa promoter. increase ...	1999	10564496
cytosolic delivery of granzyme b by bacterial toxins: evidence that endosomal disruption, in addition to transmembrane pore formation, is an important function of perforin.	granule-mediated cell killing by cytotoxic lymphocytes requires the combined actions of a membranolytic protein, perforin, and granule-associated granzymes, but the mechanism by which they jointly kill cells is poorly understood. we have tested a series of membrane-disruptive agents including bacterial pore-forming toxins and hemolytic complement for their ability to replace perforin in facilitating granzyme b-mediated cell death. as with perforin, low concentrations of streptolysin o and pneumo ...	1999	10567584
in vitro activity of levofloxacin against gram-positive bacteria.	the in vitro activity of levofloxacin was investigated against 256 clinical strains of four gram-positive genera (staphylococcus, streptococcus, enterococcus, and listeria). ofloxacin and ciprofloxacin were used as comparators. uniform susceptibility to levofloxacin was recorded among methicillin-susceptible staphylococci, streptococci other than streptococcus agalactiae, regardless of their being susceptible, intermediate, or resistant to penicillin (s. pneumoniae) or erythromycin (s. pyogenes ...	1999	10567771
[a prospective study of meningitis diagnosed in a 3rd-level hospital during a 1-year period].	one-year prospective observational study of meningitis diagnosed at a third level hospital.	1999	10568149
listeria monocytogenes possesses adhesins for fibronectin.	listeria monocytogenes is a gram-positive, nonsporulating, food-borne pathogen of humans and animals that is able to invade many eukaryotic cells. several listerial surface components have been reported to interact with eukaryotic cell receptors, but the complete mechanism by which the bacteria interact with all of these cell types remains largely unknown. in this work, we found that l. monocytogenes binds to human fibronectin, a 450,000-da dimeric glycoprotein found in body fluids, on the surfa ...	1999	10569795
bacterial microflora of wild brown trout (salmo trutta), wild pike (esox lucius), and aquacultured rainbow trout (oncorhynchus mykiss).	initial numbers of bacteria associated with wild (brown trout and pike) and cultured (rainbow trout) freshwater fish as well as with the water in which they were caught were determined. subsequently, a total of 979 randomly selected isolates were characterized and identified to the genus level. for all counts performed (aerobes, psychrotrophs, anaerobes, enterobacteriaceae, and enterococci), no significant differences were observed in water samples, the highest level corresponding to psychrotrop ...	1999	10571316
microbiological quality and safety of ready-to-eat street-vended foods in johannesburg, south africa.	fifty-one ready-to-eat street foods, 18 dishwater, and 18 surface swab samples were collected from six vendors in johannesburg, south africa. food temperatures were recorded at the time of sampling. standard methods were used to determine aerobic plate counts (apcs), spore counts (scs), and enterobacteriaceae counts (ecs) for food samples as well as coliform counts (ccs) for water and swab samples. in addition, petrifilm escherichia coli count (pc) plates were used for the enumeration of colifor ...	1999	10571317
thin agar layer method for recovery of heat-injured listeria monocytogenes.	a thin agar layer (tal) method was developed to recover heat-injured listeria monocytogenes. modified oxford medium (mox), a selective plating medium, inhibits heat-injured l. monocytogenes from growing, whereas tryptic soy agar (tsa), a nonselective medium, does not. in order to facilitate recovery of heat-injured l. monocytogenes cells while providing selectivity of isolation of l. monocytogenes from other bacteria in the sample, a unique tal procedure was developed by overlaying 5 ml of nonse ...	1999	10571328
genes of the sbo-alb locus of bacillus subtilis are required for production of the antilisterial bacteriocin subtilosin.	bacillus subtilis jh642 and a wild strain of b. subtilis called 22a both produce an antilisterial peptide that can be purified by anion-exchange and gel filtration chromatography. amino acid analysis confirmed that the substance was the cyclic bacteriocin subtilosin. a mutant defective in production of the substance was isolated from a plasmid gene disruption library. the plasmid insertion conferring the antilisterial-peptide-negative phenotype was located in a seven-gene operon (alb, for antili ...	1999	10572140
use of enterocin ccm 4231 to control listeria monocytogenes in experimentally contaminated dry fermented hornád salami.	the effectiveness of enterocin ccm 4231 in controlling listeria monocytogenes contamination in dry fermented hornád salami was examined. three independent salami treatments were conducted under pilot plant and laboratory conditions. salamis were produced according to standard technological parameters and stages with ripening for 3 weeks. the reference samples consisted of the meat mixture without either l. monocytogenes or bacteriocin addition. the control sample (cs) consisted of the meat mixtu ...	1999	10573399
behaviour of l. monocytogenes in an artificially made biofilm of a nisin-producing strain of lactococcus lactis.	the survival of listeria monocytogenes in a binary biofilm with a bacteriocin producer (lactococcus lactis cnrz 150) was investigated. two situations were simulated: in the first, l. monocytogenes was deposited on a 1-day biofilm of lactococcus lactis (deferred adhesion); in the second, l. monocytogenes was simultaneously mixed with lact. lactis (simultaneous adhesion). biofilms were cultivated in tryptic soy broth supplemented with 6 g l(-1) of yeast extract (tsb-ye) and l. monocytogenes counts ...	1999	10574092
isolation and detection of listeria spp, salmonella spp and yersinia spp using a simultaneous enrichment step followed by a surface adhesion immunofluorescent technique.	the use of a rapid surface adhesion immunofluorescent (saif) technique for the isolation of three pathogens using a single enrichment step from broth and enriched meat cultures was investigated. buffered peptone water (bpw, 225 ml) was inoculated with listeria monocytogenes, salmonella enteritidis and yersinia enterocolitica to a level of 10 cfu ml(-1) and incubated overnight at 30 degrees c. minced beef samples (25 g) were inoculated with the three pathogens to a level of 100 cfu g(-1) and incu ...	1999	10579505
cerebrospinal fluid levels of soluble cd14 in inflammatory and non-inflammatory diseases of the cns: upregulation during bacterial infections and viral meningitis.	the cd14 antigen, an important cell surface molecule of monocytic cells, is involved in cellular activation: it binds lipopolysaccharide and other cellular lipid structures. brain macrophages play a pivotal role during inflammatory reactions of the cns parenchyma, ventricles and meninges. a soluble form of cd14 (scd14) was measured in paired cerebrospinal fluid (csf) and serum samples from 91 patients with different neurological diseases. mean levels of circulating scd14 in csf in a control grou ...	1999	10580799
autolysis of listeria monocytogenes.	physiological conditions that could provide maximal rates of autolysis of listeria monocytogenes were examined. l. monocytogenes was found to be refractory to most treatments that promote rapid autolysis in other bacteria. best rates of autolysis were obtained after resuspending the cells in tris-hydrochloride buffer at 37 degrees c with the ph optimum at 8.0. autolysis was also efficiently promoted by the surfactant triton x-100. antibiotics that interfere with the biosynthesis of the cell wall ...	1999	10581670
osmoprotection of escherichia coli by peptone is mediated by the uptake and accumulation of free proline but not of proline-containing peptides.	the effect of meat peptone type i (sigma) on the growth of escherichia coli cells under hyperosmotic stress has been investigated. peptone is a complex mixture of peptides with a small content of free amino acids, which resembles nutrients found in natural environments. our data showed that peptone enhances the growth of e. coli cells in high-osmolarity medium to levels higher than those achieved with the main compatible solute in bacteria, glycine betaine. the mechanism of osmoprotection by pep ...	1999	10583976
listeria monocytogenes scott a: cell surface charge, hydrophobicity, and electron donor and acceptor characteristics under different environmental growth conditions.	we determined the variations in the surface physicochemical properties of listeria monocytogenes scott a cells that occurred under various environmental conditions. the surface charges, the hydrophobicities, and the electron donor and acceptor characteristics of l. monocytogenes scott a cells were compared after the organism was grown in different growth media and at different temperatures; to do this, we used microelectrophoresis and the microbial adhesion to solvents method. supplementing the ...	1999	10583984
agar underlay method for recovery of sublethally heat-injured bacteria.	a method of recovering sublethally heat-injured bacteria was developed. the procedure (termed the agar underlay method) uses a nonselective agar underlaid with a selective medium. in a two-chambered petri dish, the lutri plate (lp), a nonselective agar is inoculated with a population of sublethally heat-injured bacteria. after a 2-h repair incubation period, selective agar is added to the bottom chamber of the lp and incubated. by diffusing through the nonselective top agar, selective agents fro ...	1999	10583985
cloning, sequencing, and characterization of genomic subtracted sequences from listeria monocytogenes.	individual sequences of a genomic subtracted, pcr-amplified, mixed-sequence probe (gs probe) were cloned and sequenced. the gs probe differentiated restriction fragment length polymorphism patterns for listeria monocytogenes but did not hybridize with members of other bacterial genera. sequence analysis identified several l. monocytogenes sequences already present in the genbank database; the putative identities of other sequences were inferred from homology data, and still other sequences did n ...	1999	10583999
cytokine secretion by stimulated monocytes depends on the growth phase and heat treatment of bacteria: a comparative study between lactic acid bacteria and invasive pathogens.	the consumption of food containing lactic acid bacteria (lab) has been shown to exert immunomodulatory effects in humans. the specific cellular interaction of these bacteria with immuno-competent cells has not yet been fully understood. since the tnf-alpha secretion of stimulated monocytes is an important initial response to a bacterial challenge, we investigated the potential of lab originating from the human intestine or fermented food in comparison to the effect of invasive pathogens. the cha ...	1999	10585139
the adjacent flanking region plays a critical role in facilitating the presentation of the listeria monocytogenes product lema to h2 m3wt-restricted, peptide-specific murine cd8 cells.	mice infected with listeria monocytogenes (lm) generate cd8 effectors specific for f-migwii, the amino terminus of the bacterial product lema presented by the class ib mhc molecule h2 m3wt. lema has several distinctive properties: 1) it is readily presented as an exogenous ag in the absence of bacterial infection; 2) it is processed by a tap-independent pathway, which is sensitive to chloroquine, pepstatin, and brefeldin; and 3) the immunogenic portion of the molecule is extremely resistant to p ...	1999	10586072
cooperative symmetry-breaking by actin polymerization in a model for cell motility.	polymerizing networks of actin filaments are capable of exerting significant mechanical forces, used by eukaryotic cells and their prokaryotic pathogens to change shape or to move. here we show that small beads coated uniformly with a protein that catalyses actin polymerization are initially surrounded by symmetrical clouds of actin filaments. this symmetry is broken spontaneously, after which the beads undergo directional motion. we have developed a stochastic theory, in which each actin filame ...	1999	10587645
breaking through an actin cloud.		1999	10587655
intracerebral activity of antibiotics against listeria monocytogenes during experimental rhombencephalitis.	we used a model of rhombencephalitis in gerbils to test the efficacy of various antibiotics against listeria monocytogenes. gerbils were inoculated in the middle ear with strain egd and treated subcutaneously with various antibiotics alone or in combination. we found that the most active antibiotics on intracerebral bacteria were amoxycillin, co-trimoxazole, rifampicin and imipenem. vancomycin, gentamicin and ciprofloxacin were weakly or not active. the combinations amoxycillin-co-trimoxazole, a ...	1999	10588323
control of early viral and bacterial distribution and disease by natural antibodies.	natural antibodies are often dismissed from immunological analysis as "background," but they may play an important role in conferring immunity against infections. in antibody-free mice infected with various viruses or with listeria monocytogenes, viral or bacterial titers in peripheral organs, including the kidney and brain, were 10 to 100 times greater than in antibody-competent mice (and enhanced their susceptibility to some infections), and titers in secondary lymphoid organs were 10 to 100 t ...	1999	10591647
interaction between the protein inlb of listeria monocytogenes and lipoteichoic acid: a novel mechanism of protein association at the surface of gram-positive bacteria.	inlb is a listeria monocytogenes protein that is sufficient to promote entry in a variety of mammalian cells. the last 232-amino-acid domain (csa) of inlb has been shown to mediate attachment on the listerial surface, although its sequence does not suggest any known mechanism of association to the bacterial surface. inlb is present both on the bacterial surface and in culture supernatants. as has been recently demonstrated, both forms of inlb, soluble and surface-bound, can trigger signalling in ...	1999	10594817
introduction of protein or dna delivered via recombinant salmonella typhimurium into the major histocompatibility complex class i presentation pathway of macrophages.	recombinant (r) salmonella typhimurium aroa strains which display the hen egg ovalbumin ova(257-264) peptide siinfekl in secreted form were constructed. in addition, attenuated rs. typhimurium pcdna-ova constructs harbouring a eukaryotic expression plasmid encoding complete ova were used to introduce the immunodominant ova(257-264) epitope into the major histocompatibility complex (mhc) class i presentation pathway. both modes of antigen delivery (dna and protein) by salmonella vaccine carriers ...	1999	10594975
[meningitis (ii)--acute bacterial meningitis].	acute meningitis is a medical emergency, particularly in patients with rapidly progressing disease, mental status changes or neurological deficits. the majority of cases of bacterial meningitis are caused by a limited number of species, i.e. streptococcus pneumoniae, neisseria meningitis, listeria monocytogenes, group b streptococci (streptococcus agalactiae), haemophilus influenzae and enterobacteriaceae. many other pathogens can occasionally cause bacterial meningitis, often under special clin ...	1999	10596276
inhibition of listeriolysin o-induced hemolysis by bovine lactoferrin.	lactoferrin (lfr) plays an important role in the anti-microbial defense through iron binding, lipopolysaccharide binding and immunomodulation. in this study, we demonstrate that bovine lfr specifically inhibits the hemolytic activity of listeriolysin o (llo) produced by listeria monocytogenes. the hemolytic activity of llo was completely inhibited in the presence of bovine lfr that was highly purified on two cation-exchange columns, whereas that of streptolysin o or perfringolysin o was not inhi ...	1999	10598021
protective cultures inhibit growth of listeria monocytogenes and escherichia coli o157:h7 in cooked, sliced, vacuum- and gas-packaged meat.	contamination of cooked meat products with listeria monocytogenes poses a constant threat to the meat industry. the aim of this study was therefore to investigate the use of indigenous lactic acid bacteria (lab) as protective cultures in cooked meat products. cooked, sliced, vacuum- or gas-packaged ham and servelat sausage from nine meat factories in norway were inoculated with 10(3) cfu/g of a mixture of three rifampicin resistant (rif-mutant) strains of l. monocytogenes and stored at 8 degrees ...	1999	10598113
incidence of listeria monocytogenes in different types of meat products on the belgian retail market.	a survey was undertaken to determine the incidence and numbers of l. monocytogenes in a variety of meat products (cooked meat products, raw cured meat products (dried or not), mayonnaise based salads and prepared meals). as expected, raw cured meat products were significantly higher contaminated with l. monocytogenes than cooked meat products, 13.71% (113/824) and 4.90% (167/3405), respectively. also a larger proportion of raw cured meat product samples contained a high initial level of the path ...	1999	10598117
exposure to cigarette smoke impairs alveolar macrophage functions during halothane and isoflurane anesthesia in rats.	smoking alters numerous alveolar macrophage functions and is an important risk factor for postoperative pulmonary complications. the authors therefore tested the hypothesis that smoke exposure impairs antimicrobial and proinflammatory responses in alveolar macrophages during halothane and isoflurane anesthesia with mechanical ventilation.	1999	10598627
bacterial meningitis.	initial empiric therapy for community-acquired bacterial meningitis should be based on the possibility that penicillin-resistant pneumococci may be the etiologic organisms and, hence, should include a combination of third-generation cephalosporin (cefotaxime or ceftriaxone) and vancomycin. ampicillin should be included if the patient has predisposing factors that are associated with a risk for infection with listeria monocytogenes. bacterial isolates from the cerebrospinal fluid should be tested ...	1999	11096704
[enterocin-35, a bacteriocin with activity against listeria monocytogenes. possible use in the food industry].	the in vitro inhibitory activity of enterocin-35 produced by enterococcus faecium crl 35, was studied against listeria monocytogenes, isolated from seafoods. optimal growth conditions of the enterocin-35 producing strain, for higher bacteriocin production and improve the extraction and purification of these peptides, were applied. a crude extract of enterocin-35 was assayed in a frozen seafood artificially contaminated with listeria monocytogenes isolate, simulating at laboratory scale an eventu ...	1999	10979837
[listeria monocytogenes infections--ten years' experience].	7 cases of listeriosis were diagnosed here between 1988-1997 (6 in last 3 years), or 2.94/100,000 admissions. 2 elderly patients suffered from meningitis and 2 pregnant women presented with premature contractions, 1 of whom delivered a premature, infected baby. 2 other patients had fever and gastroenteritis. listeria monocytogenes was isolated from blood in 4, csf in 2 and the placenta in 1. it was isolated from those with bacterial meningitis. all patients recovered. both increased awareness fo ...	1999	10959337
cytolytic t-cell responses to human dendritic cells and macrophages infected with mycobacterium bovis bcg and recombinant bcg secreting listeriolysin.	cytolytic t-cell responses from 63 normal blood donors were monitored in a mycobacterium bovis bcg infection system in vitro. we wanted to know whether cultured dendritic cells were capable of potentiating the cytolytic t-cell responses to m. bovis bcg. infected cultured dendritic cells were up to ten times more effective antigen-presenting cells than macrophages in proliferative assays, while cytolytic t-cell induction did not differ significantly between dendritic cells and macrophages. separa ...	1999	10816080
some emerging food and water borne pathogens.	emerging pathogens are those infective organisms whose incidence has recently increased or is likely to increase during the next two decades due to changes in demography, food habits, food technology, commerce, water sources and environmental factors. some important emerging food and water borne bacterial pathogens include listeria monocytogenes, campylobacter jejuni, yersinia enterocolitica, salmonella enteritidis, escherichia coli o157: h7, vibrio cholerae biotype e1 tor serotype 0139, vibrio ...	1999	10810592
stability of the listeria monocytogenes acta protein in mammalian cells is regulated by the n-end rule pathway.	upon infection of mammalian cells, listeria monocytogenes lyses the phagosome and enters the cytosol, where it secretes proteins necessary for its intracellular growth cycle. consequently, bacterial proteins exposed to the cytosol are potential targets for degradation by host cytosolic proteases. one pathway for degradation of host cytosolic proteins, the n-end rule pathway, involves recognition of the n-terminal amino acid and is mediated by the proteasome. however, very few natural n-end rule ...	1999	11207557
poppers: more evidence of suppressed immunity.	evidence from studies in mice shows that exposure to isobutyl nitrite suppresses the immune system. this immune suppression allows for bacterial growth in the lungs and livers of infected mice and can inhibit the ability of mediastinal lymph nodes to respond to antigen-specific stimulation. the mechanism for immune suppression may be a reduction in cd4+ and cd8+ t cell populations in the mediastinal lymph nodes following pulmonary infection with listeria monocytogenes.	1999	11366577
searching for the holy grail: hiv vaccine development in the new millennium.	many reasons for the difficulty in developing an hiv vaccine were discussed at the 5th national symposium on basic aspects of vaccines. the april 1999 conference was attended by nearly 200 researchers. speakers included dr. neal nathanson of the national institutes of health (nih), who called hiv "particularly insidious." topics included envelope glycoproteins; enhancing ctl responses; soluble cd40 ligand trimer and its effect on growth of antigen-specific t cells; responses of immunized monkeys ...	1999	11367310
the anti-invasive effect of bovine lactoferrin requires an interaction with surface proteins of listeria monocytogenes.	the anti-invasive effect of bovine lactoferrin (blf) and of bovine transferrin (btf) towards l. monocytogenes, an intracellular facultative food-borne pathogen, was assayed in the enterocyte-like cell line caco-2. when 0.5 mg/ml blf were added during the infection time or preincubated with bacteria the number of internalized bacteria was noticeably decreased whereas blf was ineffective when preincubated with the enterocytes or added post infection. btf was deprived of any effect. results from di ...	1999	12783644
purification and characterization of a bacteriocin produced by lactococcus lactis subsp. lactis h-559 isolated from kimchi.	lactic acid bacteria were isolated from kimchi and screened for bacteriocin production. strain h-559, identified as lactococcus lactis subsp. lactis, exhibited the strongest antibacterial activity among them and was active against pathogenic bacteria such as listeria monocytogenes and staphylococcus aureus as well as many lactic acid bacteria. the antimicrobial substance produced by l. lactis subsp. lactis h-559 was inactivated by alpha-chymotrypsin, and protease type ix and xiv and was confirme ...	1999	16232590
expression of listeriolysin o and acta by intracellular and extracellular listeria monocytogenes.	listeria monocytogenes requires listeriolysin o (llo) and acta, the products of hly and acta, respectively, to establish a productive intracellular infection. llo is essential for vacuolar lysis and entry into the cytosol, while acta is required for bacterial spread to adjacent cells. we have used a transcriptional reporter gene system to compare the expression of acta and hly during intracellular growth to that during growth in broth cultures. the hly and acta genes were transcriptionally fused ...	1999	9864207
mutagenesis of active-site histidines of listeria monocytogenes phosphatidylinositol-specific phospholipase c: effects on enzyme activity and biological function.	listeria monocytogenes, a gram-positive facultative intracellular pathogen, produces two distinct phospholipases c. pc-plc, encoded by plcb, is a broad-range phospholipase, whereas pi-plc, encoded by plca, is specific for phosphatidylinositol. it was previously shown that pi-plc plays a role in efficient escape of l. monocytogenes from the primary phagosome. to further understand the function of pi-plc in intracellular growth, site-directed mutagenesis of plca was performed. two potential active ...	1999	9864213
existing antilisterial immunity does not inhibit the development of a listeria monocytogenes-specific primary cytotoxic t-lymphocyte response.	infection of balb/c mice with listeria monocytogenes stimulates an antilisterial immune response evident by the appearance of h2-kd-restricted cd8(+) cytotoxic t lymphocytes (ctls) specific for the nanomer peptides amino acids (aa) 91 to 99 of listeriolysin o (llo 91-99) and aa 217 to 225 of the p60 molecule (p60 217-225). we have introduced point mutations at anchor residues within llo 91-99 (92f) or p60 217-225 (218f), and balb/c mice infected with l. monocytogenes strains containing these poi ...	1999	9864223
sources of listeria monocytogenes contamination in a cold-smoked rainbow trout processing plant detected by pulsed-field gel electrophoresis typing.	sites of listeria monocytogenes contamination in a cold-smoked rainbow trout (oncorhynchus mykiss) processing plant were detected by sampling the production line, environment, and fish at different production stages. two lots were monitored. the frequency of raw fish samples containing l. monocytogenes was low. during processing, the frequency of fish contaminated with l. monocytogenes clearly rose after brining, and the most contaminated sites of the processing plant were the brining and postbr ...	1999	9872773
bacterial resistance to ultrasonic waves under pressure at nonlethal (manosonication) and lethal (manothermosonication) temperatures.	the decimal reduction times of streptococcus faecium, listeria monocytogenes, salmonella enteritidis, and aeromonas hydrophila corresponding to heat treatment at 62 degrees c were 7.1, 0.34, 0.024, and 0.0096 min, and those corresponding to manosonication treatment (40 degrees c, 200 kpa, 117 microm) were 4.0, 1.5, 0.86, and 0.90 min, respectively. the manosonication decimal reduction times of the four species investigated decreased sixfold when the amplitude was increased from 62 to 150 microm ...	1999	9872795
growth of listeria monocytogenes and yersinia enterocolitica on cooked modified-atmosphere-packaged poultry in the presence and absence of a naturally occurring microbiota.	cooked poultry cuts were inoculated with five-strain composite mixtures of either listeria monocytogenes or yersinia enterocolitica (1,000 cfu/150-g piece), packaged in 44:56 co2-n2, and stored at 3.5, 6.5, or 10 degrees c for up to 5 weeks. both l. monocytogenes and y. enterocolitica grew under all test conditions. the presence of a naturally occurring microbiota did not influence the growth of either pathogen. addition of lactate with the shelf life extender alta 2341 lengthened the lag phases ...	1999	9872806