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community-acquired pneumonia caused by legionella dumoffii in a patient with hairy cell leukemia.a case of community-acquired pneumonia caused by legionella dumoffii in a patient with hairy cell leukemia is described. diagnosis was confirmed by isolation by culture of sputum and broncho-alveolar lavage specimens, positive direct fluorescent antibody stains, and antibody seroconversion from 1:16 (acute) to 1:4096 (six months). the blue white autofluorescence of the l. dumoffii colonies when viewed under ultraviolet light was particularly useful in preliminary identification. the patient reco ...19902076912
antigen detection for the rapid diagnosis of mycoplasma and legionella pneumonia.immunologic attempts to detect mycoplasma antigens in fluids of infected patients have been rare and largely unsuccessful. nucleic acid hybridization procedures appear promising on the basis of successes in detecting mycoplasmal contamination of tissue culture cells; results of attempts to apply these techniques to human infections have not been reported. antigens can be detected in the urine of about 80% of patients with serogroup 1 legionella pneumophila pneumonia and of some patients with ser ...19862421969
[legionella dumoffii and legionella pneumophila serogroup 5 isolated from 2 cases of fulminant pneumonia].we encountered two cases of legionella pneumonia which ran a dramatic course and isolated legionella dumoffii from one patient and legionella pneumophila serogroup 5 from the other patient. the patient from whom l. dumoffii was isolated was a 59-year-old male with no basic disease. he presented chill, fever, coughing and other symptoms, starting on july 3, 1986, his disease was diagnosed as pneumonia at the clinic of his company. the patient was then introduced and admitted to our hospital. on a ...19892507680
increasing pericardial effusion in cardiac transplant recipients.although pericardial effusion after cardiac surgery is frequent and usually benign, its etiology and prognosis after cardiac transplantation are unknown. during 1 year (1985-1986), 12 of our current transplant population (total, 189) developed moderate or large pericardial effusions confirmed by two-dimensional echocardiography. these effusions occurred within 1 month of transplantation in 10 patients and at 3 months and 4.5 years in the other two. pericardiocentesis was performed because of cli ...19892645065
molecular epidemiology of legionella species by restriction endonuclease and alloenzyme analysis.as part of an ongoing investigation into nosocomial legionella infections at stanford university medical center (sumc), we applied the technique of restriction endonuclease analysis (rea) to determine strain differences among three species, including legionella pneumophila, legionella dumoffii, and legionella micdadei. a total of 26 human and environmental water isolates from sumc were selected for rea and compared with control strains that were not epidemiologically linked to sumc. rea results ...19872822760
[diagnosis of the first case of legionella dumoffii pneumonia associated with igg-lambda type multiple myeloma in japan]. 19873125286
legionella micdadei and legionella dumoffii monoclonal antibodies for laboratory diagnosis of legionella infections.two different monoclonal antibodies directed against legionella micdadei and l. dumoffii (genetic systems corp., seattle, wash.) were evaluated for their specificity and ability to detect l. micdadei and l. dumoffii in human and animal clinical samples and bacterial isolates in an indirect immunofluorescence assay. all three frozen sputum samples and all three formalin-fixed sputum and liver samples from patients with culture-documented l. micdadei pneumonia were positive when tested with the l. ...19873320084
multilocus enzyme analysis of legionella dumoffii.variability among 29 clinical and environmental strains of legionella dumoffii was investigated by multilocus enzyme analysis by use of starch gel electrophoresis. based on results of analysis at 20 enzyme loci, the strains were separated into five closely related electrophoretic types (ets), which were clearly distinguished from 53 strains representing 53 ets of l. pneumophila. dna hybridization results (hydroxyapatite method, 60 and 75 degrees c) for representative strains confirmed that all l ...19883384905
legionnaires' disease caused by legionella dumoffii in distilled water.five cases of legionnaires' disease caused by legionella dumoffii were identified within an 11-month period in a hospital in the quebec city area. in four cases bacterial isolates were obtained from clinical specimens, and in one case seroconversion was demonstrated. all the patients had been admitted to hospital within 10 days before diagnosis. two of the patients were immunosuppressed children. only 1 of the 40 hot water samples from the hospital yielded l. dumoffii; however, 6 of 11 distilled ...19863536052
an unusual legionellosis case yields the first new zealand isolation of legionella dumoffii. 19853856769
a new biotype of legionella dumoffii.a new biotype of l. dumoffii was isolated from lung and sputum samples of an immunosuppressed patient with pneumonia. this strain differs from other described strains of l. dumoffii in that it fails to produce browning of tyrosine-containing buffered yeast extract medium.19853988905
agglutinating antibody titers to members of the family legionellaceae in cystic fibrosis patients as a result of cross-reacting antibodies to pseudomonas aeruginosa.the objective of this study was to evaluate the prevalence and significance of antibody titers to organisms in the family legionellaceae in 128 serum samples collected from cystic fibrosis patients at routine examinations. antibody titers were determined for 10 antigenic types of legionellaceae; legionella pneumophila serogroups 1 to 6, fluoribacter (legionella) bozemanae, fluoribacter (legionella) dumoffii, fluoribacter (legionella) gormanii, and tatlockia (legionella) micdadei. the method of a ...19846206086
prevalence of pneumonias caused by legionella species among patients on whom autopsies were performed.we wanted to determine the prevalence of pneumonias caused by legionella species among patients on whom autopsies were performed in two medical centers in st louis from january 1976 to june 1981. we screened formaldehyde-fixed deparaffinized lung tissue sections with microscopic evidence of pneumonia from 97 patients with use of the direct immunofluorescence antibody technique with a multivalent antilegionella conjugate containing antibodies to legionella pneumophila serogroups 1 through 4 plus ...19836344838
[legionella dumoffii pneumonia observed during an influenza epidemic]. 19846472837
isolation of legionella species from drinking water.three different species of legionella were recovered from samples of water taken from chlorinated public water supplies where no coliform bacteria were simultaneously detected. five of 856 samples yielded legionella isolates. three isolates were identified as legionella pneumophila serogroup 1, the fourth was identified as legionella dumoffii, and the fifth was identified as legionella jordanis. studies to determine the survival of l. pneumophila flint 1 serogroup 1 in tap water at various tempe ...19846508292
clinical laboratory differentiation of legionellaceae family members with pigment production and fluorescence on media supplemented with aromatic substrates.a systematic study of pigment production (browning) and fluorescence (extracellular yellow-green and intracellular blue-white) by nine legionellaceae species was performed. a total of 56 strains representing tatlockia micdadei (pittsburgh pneumonia agent), legionella pneumophila, legionella jordanis, legionella longbeachae, legionella oakridgensis, legionella wadsworthii, fluoribacter bozemanae, fluoribacter gormanii, and fluoribacter dumoffii could be separated on media supplemented with tyrosi ...19846547453
[legionella dumoffii pneumonia with adult respiratory distress syndrome]. 19836867652
electrophoretic characterization of soluble protein extracts of legionella pneumophila and other members of the family legionellaceae.the soluble peptides of strains of legionella pneumophila, tatlockia micdadei, fluoribacter bozemanae, fluoribacter dumoffii, and fluoribacter gormanii were studied by polyacrylamide gel electrophoresis. characteristic patterns were seen for legionella and tatlockia strains, whereas the patterns for the fluoribacter strains were variable as would be expected for this genetically heterogeneous group. grouping by peptide pattern was consistent with proposed taxons based on dna-dna homology. by usi ...19836874904
legionella micdadei (pittsburgh pneumonia agent): direct fluoresent-antibody examination of infected human lung tissue and characterization of clinical isolates.legionella micdadei (pittsburgh pneumonia agent) was identified by direct fluorescent-antibody (dfa) examination of lung tissue in six of seven persons diagnosed previously as having l. micdadei pneumonia only by histopathology and in four persons who also had positive cultures of the organism. no cross-reactions occurred with monospecific dfa conjugates prepared against legionella pneumophila serogroups 1 to 6, legionella bozemanii, legionella dumoffii, and legionella gormanii. one person had l ...19817014621
fluorescent-antibody detection of legionella dumoffii in a fatal case of pneumonia.legionella dumoffii organisms were detected in the lung tissue from a patient with a fatal case of pneumonia, the second reported to date. a fluorescent-antibody conjugate specific for the tex-kl organism isolated in 1979 revealed many l, dumoffii organisms in lung tissue obtained postmortem from this patient.19817014626
detection of cell-associated or soluble antigens of legionella pneumophila serogroups 1 to 6, legionella bozemanii, legionella dumoffii, legionella gormanii, and legionella micdadei by staphylococcal coagglutination tests.current methods used for the detection of whole-cell isolates of legionella or for the detection of legionella soluble antigens are technically impractical for many clinical laboratories. the purpose of this study was to explore practical alternatives. the results showed that whole cell isolates of legionella pneumophila serogroups 1 to 6, legionella bozemanii, legionella dumoffii, legionella gormanii, and legionella micdadei were identified specifically by a simple slide agglutination test or s ...19817287888
susceptibility of pittsburgh pneumonia agent (legionella micdadei) and other newly recognized members of the genus legionella to nineteen antimicrobial agents.the susceptibilities of 11 strains representing the five recognized species of legionella were determined by agar dilution testing on buffered charcoal-yeast extract agar. all of the legionellae tested were susceptible to rifampin, erythromycin, rosaramycin, chloramphenicol, and the aminoglycosides and were resistant to clindamycin and vancomycin. susceptibilities to penicillins and cephalosporins were variable. legionella micdadei, legionella bozemanii, and legionella gormanii were susceptible ...19817325645
[legionella dumoffii pneumonia]. 19957734509
pulmonary infection due to legionella cincinnatiensis in renal transplant recipients: two cases and implications for laboratory diagnosis.we report two cases of pneumonia caused by legionella cincinnatiensis, a species previously identified as a pathogen in only one other instance. both infections occurred in renal transplant recipients who were receiving only moderate doses of immunosuppressive drugs several years after transplantation; both patients had no recent episodes of rejection. their clinical courses varied from mild symptoms to multisystem organ failure and death. species identification by direct fluorescent antibody te ...19948011820
presence of legionella spp. in thermal springs of the campania region of south italy.water samples from 66 thermal springs in the campania region of south italy were cultured for legionella spp., pseudomonas aeruginosa, and indicators of faecal pollution. the temperature of the sources ranged from 21 degrees c to 59.5 degrees c. legionella pneumophila, serogroup 7-10, was isolated from two out of 60 sources on the island of ischia and legionella dumoffii from one mainland source. the temperatures of these sources were 35.2 degrees c, 48.2 degrees c, and 52.0 degrees c respective ...19968914132
entry and intracellular localization of legionella dumoffii in vero cells.organisms of some legionella species are known to internalize and multiply within epithelial cell lines. during the study on interaction between legionella spp. and vero cells, we found that l. dumoffii tex-kl (atcc 33343) can enter into vero cells approximately four to 20 times more often than five other strains of four species of legionella. the mode of entry between l. dumoffii tex-kl and l. pneumophila philadelphia-1 was compared and studied by treating vero cells with reagents which inhibit ...19989480789
a review of the in-vitro activity of quinupristin/dalfopristin against intracellular pathogens and mycoplasmas.quinupristin/dalfopristin displays in-vitro bacteriostatic activity against all legionella spp. (mics = 0.06-2 mg/l), with legionella pneumophila usually being at least two-fold more sensitive to quinupristin/dalfopristin than legionella bozemanii, legionella dumoffii, legionella gormanii and legionella micdadei (mic = 0.06-2 vs 1-2 mg/l, respectively). against legionella spp., quinupristin/dalfopristin was at least as active as erythromycin. quinupristin/dalfopristin was active in vitro against ...19979511064
serum cytokines in patients with legionella pneumonia: relative predominance of th1-type cytokines.serum samples from 14 patients with legionella pneumonia were examined for the presence of cytokines. in spite of high levels of serum c-reactive protein in all patients during the acute phase in only four cases (one involving interleukin-1beta [il-1beta], three involving il-6, and none involving tumor necrosis factor alpha) was the concentration of cytokines more than 100 pg/ml. th2 cytokines il-4 and il-10 were detected in only one patient each. in contrast, significant increases of serum gamm ...19989605998
entry and intracellular growth of legionella dumoffii in alveolar epithelial cells.we have found that legionella dumoffii strain tex-kl (atcc 33343) invades into and proliferates in the human lung alveolar epithelial-cell line a549 in vitro. the organism associated with the a549 cells at a 10-fold greater magnitude than l. pneumophila philadelphia-1 during in vitro coculture for 1 h. thereafter, l. dumoffii tex-kl invaded the cells at a significantly higher rate (100- to 1,000-fold) than did l. pneumophila philadelphia-1. after internalization, however, both bacteria prolifera ...19989620934
comparison of the binax legionella urinary antigen enzyme immunoassay (eia) with the biotest legionella urin antigen eia for detection of legionella antigen in both concentrated and nonconcentrated urine samples.we evaluated a newly commercial enzyme immunoassay (eia) (biotest legionella urin antigen eia; biotest ag, dreieich, germany) for detection of antigens of all legionella pneumophila serogroups with a relatively wide spectrum of cross-reactivity as well as antigens of other legionella spp. by comparing its sensitivity and specificity with those of an eia for detection of l. pneumophila serogroup 1 antigen (legionella urinary antigen eia; binax, portland, maine). both tests were performed with bot ...19989705420
systemic infection of an immunocompromised patient with methylobacterium zatmanii.we describe the identification of methylobacterium zatmanii as the causative agent of bacteremia and fever in an immunocompromised patient. the patient, a 60-year-old man, had a 5-month history of acute myeloid leukemia and had been on chemotherapy throughout this period. seven days after the onset of neutropenia, the patient developed fever. the combination of ciprofloxacin, co-trimoxazole, imipenem, amikacin, and vancomycin led to a complete defervescence. on subculture from six positive blood ...19999854105
legionella pneumophila invasion of mrc-5 cells induces tyrosine protein phosphorylation.after uptake and intracellular multiplication of legionella pneumophila in mrc-5 lung fibroblasts, important cytoskeletal filament structures, like actin, tubulin, or vimentin, and a cell membrane-associated fibronectin were rearranged during early infection, resulting in a loss of cell adhesion and collapse of the cytoskeleton. dysregulation of the cellular phosphorylation and dephosphorylation cascade may contribute to the observed changes and may support intracellular survival and multiplicat ...199910456891
detection of legionella dna in peripheral leukocytes, serum, and urine from a patient with pneumonia caused by legionella dumoffii.the polymerase chain reaction (pcr) has been used to detect legionella dna in respiratory tract, serum, and urine samples from patients with pneumonia. in addition, a preliminary study using a guinea pig model suggested that testing of peripheral leukocytes by pcr may be more sensitive than testing of other samples. we used pcr to detect legionella dna in serial peripheral leukocyte (buffy coat), serum, and urine samples from a patient with pneumonia caused by legionella dumoffii. legionella dna ...200010671345
rapid identification of clinically relevant legionella spp. by analysis of transfer dna intergenic spacer length polymorphism.analysis of pcr-amplified transfer dna (tdna) intergenic spacers was evaluated as a rapid method for identification to the species level of 18 species of legionella known as human pathogens. type strains (n = 19), reference strains (n = 16), environmental strains (n = 31), and clinical strains (n = 32) were tested. pcr products using outwardly directed tdna consensus primers were separated on polyacrylamide gels and analyzed with automated laser fluorescence. test results were obtained in 8 h st ...200111136765
morphological variety of intracellular microcolonies of legionella species in vero cells.intracellular microcolonies of six legionella species growing in vero cells showed distinctly varied morphologies. the varieties were observed by light microscopy of gimenez-stained, legionella-infected vero cells and by electron microscopy (em). legionella pneumophila philadelphia-1 formed needle-shaped crystal-like microcolonies. legionella bozemanii wiga formed microcolonies like wool balls containing filamentous cells. in em, these organisms proliferated in endosomes, which were adjacent to ...200111529563
in vitro activity of abt-773 against legionella pneumophila, its pharmacokinetics in guinea pigs, and its use to treat guinea pigs with l. pneumophila pneumonia.the activity of abt-773 was studied against extracellular and intracellular legionella pneumophila and for the treatment of guinea pigs with l. pneumophila pneumonia. the abt-773 mic at which 50% of isolates are inhibited (mic(50)) for 20 different legionella sp. strains was 0.016 microg/ml, whereas the mic(50)s of clarithromycin and erythromycin were 0.032 and 0.125 microg/ml, respectively. abt-773 (1 microg/ml) was bactericidal for two l. pneumophila strains grown in guinea pig alveolar macrop ...200111557455
isolation of elemental sulfur as a self-growth-inhibiting substance produced by legionella pneumophila.the addition of hp-20 resin to a medium could enhance the growth of legionella species. elemental sulfur was isolated as a self-growth-inhibiting substance produced endogenously by legionella pneumophila from methanol extracts of the resins used to culture the bacterium. elemental sulfur shows strong growth-inhibiting activity toward all legionella species tested.200212324324
detection of legionella dna by pcr of whole-blood samples in a mouse model.a detection system for legionella dna in blood samples based on the pcr was developed and evaluated in a/j mice with experimentally induced legionella pneumonia. primers were designed to amplify a 106 bp dna fragment of the 16s rrna gene specific to legionella species. the pcr system could detect clinically relevant legionella species including legionella pneumophila, legionella micdadei, legionella bozemanae, legionella dumoffii, legionella longbeachae, legionella gormanii and legionella jordan ...200312676871
characterization of a tandem repeat polymorphism in legionella pneumophila and its use for genotyping.we have analyzed the variability of minisatellite sequences (also called variable-number tandem repeats [vntrs]) in the genome of legionella pneumophila. based upon the genome sequence of the philadelphia-1 strain (serogroup 1), 25 minisatellites were selected and their polymorphisms were analyzed by pcr with the dna of serogroup 1 to 14 reference strains. for 22 markers, a pcr product of the expected size was found with the dna of the philadelphia-1 strain. most of these markers did not amplify ...200312734211
neonatal sudden death due to legionella pneumonia associated with water birth in a domestic spa bath.we report the first case of neonatal legionnaires' disease associated with water birth in a spa bath at home. legionella pneumophila serogroup 6 was detected from postmortem lung tissue.200312734286
[rapid and simple detection of legionella species by lamp, a mew dna amplification method].legionella is a common cause of community-acquired respiratory tract infections and occasionally causes nosocomial pneumonia. rapid and accurate detection of legionellae is important for diagnosis and treatment of patients. in order to detect legionellae, a new dna amplification method was designed and evaluated. loop-mediated isothermal amplification (lamp) method amplifies dna with high specificity, sensitivity, and rapidity under isothermal conditions at 65 degrees c. this method employs a dn ...200314984304
characterization of the alternative sigma factor sigma54 and the transcriptional regulator fleq of legionella pneumophila, which are both involved in the regulation cascade of flagellar gene expression.we cloned and analyzed legionella pneumophila corby homologs of rpon (encoding sigma(54)) and fleq (encoding sigma(54) activator protein). two other genes (fler and pilr) whose products have a sigma(54) interaction domain were identified in the genome sequence of l. pneumophila. an rpon mutant strain was nonflagellated and expressed very small amounts of the flaa (flagellin) protein. like the rpon mutant, the fleq mutant strain of l. pneumophila was also nonflagellated and expressed only small a ...200415090493
legionella dumoffii djla, a member of the dnaj family, is required for intracellular growth.legionella dumoffii is one of the common causes of legionnaires' disease and is capable of replicating in macrophages. to understand the mechanism of survival within macrophages, transposon mutagenesis was employed to isolate the genes necessary for intracellular growth. we identified four defective mutants after screening 790 transposon insertion mutants. two transposon insertions were in genes homologous to icmb or dotc, within dot/icm loci, required for intracellular multiplication of l. pneu ...200415155669
legioliulin, a new isocoumarin compound responsible for blue-white autofluorescence in legionella (fluoribacter) dumoffii under long-wavelength uv light.legionella dumoffii is one of the causative agents of legionnaires' disease. there are 50 species in the genus legionella, of which 10 species including l. dumoffii are known to exhibit uncharacterized blue-white autofluorescence. we constructed an l. dumoffii strain that exhibited a high intensity blue-white fluorescence, isolated a fluorescent pigment from the strain, and determined its molecular formula to be c(19)h(14)o(3) by high-resolution mass spectrometry. an nmr analysis revealed that t ...200415381093
development and evaluation of chlamylege, a new commercial test allowing simultaneous detection and identification of legionella, chlamydophila pneumoniae, and mycoplasma pneumoniae in clinical respiratory specimens by multiplex pcr.this study describes the development and evaluation of a new commercial test, chlamylege (argene inc.), which allows the simultaneous detection in respiratory samples of chlamydophila pneumoniae, mycoplasma pneumoniae, and most legionella species, as well as pcr inhibitors, by using a multiplex pcr and microplate hybridization. the sensitivities of chlamylege were 1 x 10(-3) ifu, 5 x 10(-2) color-changing units, and 1 cfu per reaction tube for c. pneumoniae, m. pneumoniae, and legionella pneumop ...200516000443
characterization of legionella pneumophila pmia, a gene essential for infectivity of protozoa and macrophages.the ability of legionella pneumophila to cause pneumonia is dependent on intracellular replication within alveolar macrophages. the icm/dot secretion apparatus is essential for the ability of l. pneumophila to evade endocytic fusion, to remodel the phagosome by the endoplasmic reticulum (er), and to replicate intracellularly. protozoan and macrophage infectivity (pmi) mutants of l. pneumophila, which include 11 dot/icm mutants, exhibit defects in intracellular growth and replication within both ...200516177298
in vitro activity of pazufloxacin, tosufloxacin and other quinolones against legionella species.the activities of pazufloxacin and tosufloxacin against legionella spp. were evaluated in vitro and compared with those of other quinolones, macrolides and azithromycin.200516260445
legionella confirmation using real-time pcr and syto9 is an alternative to current methodology.the currently accepted culture techniques for the detection of legionella spp. in water samples (as/nzs 3896:1998 and iso 11731 standard methods) are slow and laborious, requiring from 7 to 14 days for a result. we describe a fully validated rapid confirmation technique that uses real-time pcr incorporating the intercalating dye syto9 for the direct identification of primary cultures, significantly decreasing turnaround time and allowing faster remedial action to be taken by the industry.200516332896
outbreak of legionnaires' disease on a cruise ship linked to spa-bath filter stones contaminated with legionella pneumophila serogroup 5.in january 2003, two cases of legionnaires' disease associated with a ship's cruise were registered in the database of national epidemiological surveillance of infectious diseases. a 70-year-old male heavy smoker with mild emphysema contracted the disease during a cruise. legionella pneumophila serogroup (sg) 5 was isolated from the patient's sputum and the ship's indoor spa. the isolate from the spa matched the patient's isolate by genotyping performed by pulsed-field gel electrophoresis (pfge) ...200616490144
outbreak of legionnaires' disease on a cruise ship linked to spa-bath filter stones contaminated with legionella pneumophila serogroup 5.in january 2003, two cases of legionnaires' disease associated with a ship's cruise were registered in the database of national epidemiological surveillance of infectious diseases. a 70-year-old male heavy smoker with mild emphysema contracted the disease during a cruise. legionella pneumophila serogroup (sg) 5 was isolated from the patient's sputum and the ship's indoor spa. the isolate from the spa matched the patient's isolate by genotyping performed by pulsed-field gel electrophoresis (pfge) ...200616490144
identification of non-dot/icm suppressors of the legionella pneumophila deltadotl lethality phenotype.legionella pneumophila, a causative agent of bacterial pneumonia, survives inside phagocytic cells by avoiding rapid targeting to the lysosome. this bacterium utilizes a type ivb secretion system, encoded by the dot/icm genes, to replicate inside host cells. dotl, a critical component of the dot/icm secretion apparatus, functions as the type iv coupling protein. in contrast to most dot/icm genes, which are dispensable for growth on bacteriological media, dotl is required for the viability of wil ...200616997951
legionella impletisoli sp. nov. and legionella yabuuchiae sp. nov., isolated from soils contaminated with industrial wastes in japan.in this study, we tried to isolate legionellae from nine legionella dna-positive soil samples collected from four different sites contaminated with industrial wastes in japan. using culture methods with or without acanthamoeba culbertsoni, a total of 22 isolates of legionellae were obtained from five of the nine samples. identification of species and/or serogroups (sgs), performed by dna-dna hybridization and agglutination tests, revealed that the 22 isolates consisted of ten isolates of legione ...200717197147
[largest outbreak of legionellosis associated with spa baths: comparison of diagnostic tests].in july 2002, a large outbreak of legionellosis occurred in a bathhouse with spa facilities in miyazaki prefecture. among the visitors, 295, including suspected cases had pneumonia and/or symptoms of fever, coughing, etc. of these, 37% were hospitalized and 7 died. clinical samples from 95 mainly inpatients were collected and microbiologically tested at our laboratory. legionella pneumophila serogroup (sg) 1 was isolated from 3 of 24 in sputum culture, and none of the 3 had been treated effectiv ...200717447476
complete nucleotide sequence of pld-tex-kl, a 66-kb plasmid of legionella dumoffii tex-kl strain.the complete nucleotide sequence of a large (66 kb) plasmid pld-tex-kl of legionella dumoffii tex-kl strain was determined. of the 57 predicted open reading frames (orfs), 39 (68%) encoded proteins similar to previously known proteins, five (9%) were assigned with putative functions, three (5%) encoded conserved hypothetical proteins, and 10 (18%) had no homology to any genes present in the current open databases. the orfs with similar functions were organized in a modular structure; thus, trans ...200717881053
mechanisms of legionella pneumophila-induced interleukin-8 expression in human lung epithelial cells.legionella pneumophila is a facultative intracellular bacterium, capable of replicating within the phagosomes of macrophages and monocytes, but little is known about its interaction with human lung epithelial cells. we investigated the effect of l. pneumophila on the expression of interleukin-8 (il-8) in human a549 alveolar and nci-h292 tracheal epithelial cell lines.200718034886
infection of cultured human endothelial cells by legionella pneumophila.legionella pneumophila is a gram-negative pathogen that causes a severe pneumonia known as legionnaires' disease. here, we demonstrate for the first time that l. pneumophila infects and grows within cultured human endothelial cells. endothelial infection may contribute to lung damage observed during legionnaires' disease and to systemic spread of this organism.200818431493
legionella pneumophila infection induces programmed cell death, caspase activation, and release of high-mobility group box 1 protein in a549 alveolar epithelial cells: inhibition by methyl prednisolone.legionella pneumophila pneumonia often exacerbates acute lung injury (ali) and acute respiratory distress syndrome (ards). apoptosis of alveolar epithelial cells is considered to play an important role in the pathogenesis of ali and ards. in this study, we investigated the precise mechanism by which a549 alveolar epithelial cells induced by l. pneumophila undergo apoptosis. we also studied the effect of methyl prednisolone on apoptosis in these cells.200818447956
djla, a membrane-anchored dnaj-like protein, is required for cytotoxicity of clam pathogen vibrio tapetis to hemocytes.djla is an inner membrane cochaperone belonging to the dnaj family, which has been shown to be involved in legionella sp. pathogenesis. in this study, we explored the role of this protein in the physiology and virulence of vibrio tapetis, the etiological agent of brown ring disease (brd) in manila clam (ruditapes philippinarum). analysis of the djla locus in v. tapetis revealed a putative organization in an operon with a downstream gene that we designated duf924(vt), which encodes a conserved pr ...200818641167
conjugative plasmid pld-tex-kl promotes growth of host bacterium legionella dumoffii at low temperatures.legionella (fluoribacter) dumoffii is a resident of various aquatic environments and occasionally causes pneumonia in humans. we found that l. dumoffii strain tex-kl carries a 66-kb circular plasmid. as predicted by the presence of tra genes similar to those of other transferable plasmids, we showed that pld-tex-kl was actually capable of transferring itself to a plasmid-cured derivative of the original strain. unexpectedly, this plasmid-free derivative turned out to be partially defective in te ...200919415237
secretion of gob metallo-beta-lactamase in escherichia coli depends strictly on the cooperation between the cytoplasmic dnak chaperone system and the sec machinery: completion of folding and zn(ii) ion acquisition occur in the bacterial periplasm.metallo-beta-lactamases (mbetals) are zinc-dependent enzymes produced by many clinically relevant gram-negative pathogens that can hydrolyze most beta-lactam antibiotics. mbetals are synthesized in the bacterial cytoplasm as precursors and are secreted into the periplasm. here, we report that the biogenesis process of the recently characterized mbetal gob-18 demands cooperation between a main chaperone system of the bacterial cytoplasm, dnak, and the sec secretion machinery. using the expression ...200919433552
exploitation of conserved eukaryotic host cell farnesylation machinery by an f-box effector of legionella pneumophila.farnesylation involves covalent linkage of eukaryotic proteins to a lipid moiety to anchor them into membranes, which is essential for the biological function of ras and other proteins. a large cadre of bacterial effectors is injected into host cells by intravacuolar pathogens through elaborate type iii-vii translocation machineries, and many of these effectors are incorporated into the pathogen-containing vacuolar membrane by unknown mechanisms. the dot/icm type iv secretion system of legionell ...201020660614
septic arthritis caused by legionella dumoffii in a patient with systemic lupus erythematosus-like disease.we describe a patient with systemic lupus erythematosus (sle)-like disease on immunosuppressive treatment who developed septic arthritis of the knee involving legionella dumoffii. cultures initially remained negative. a broad-range 16s pcr using synovial fluid revealed l. dumoffii rrna genes, a finding that was subsequently confirmed by positive legionella culture results.201021106784
identification of legionella pneumophila serogroups and other legionella species by mip gene sequencing.the virulence factor known as the macrophage infectivity potentiator (mip) is responsible for the intracellular survival of legionella species. in this study, we investigated the potential of the mip gene sequence to differentiate isolates of different species of legionella and different serogroups of legionella pneumophila. we used 35 clinical l. pneumophila isolates and one clinical isolate each of legionella micdadei, legionella longbeachae, and legionella dumoffii (collected from hospitals a ...201122015397
detection of coccidioides species in clinical specimens by real-time pcr.coccidioides spp. are dimorphic fungal pathogens endemic to the semiarid regions of north, central, and south america. currently, direct smear and culture are the most common means of identifying coccidioides spp. while these methods offer relatively sensitive and specific means of detecting coccidioides spp., growth in culture may take up to 3 weeks, potentially delaying the diagnosis and initiation of appropriate antifungal therapy. in addition, growth of the organism represents a significant ...200617108077
detection of coccidioides species in clinical specimens by real-time pcr.coccidioides spp. are dimorphic fungal pathogens endemic to the semiarid regions of north, central, and south america. currently, direct smear and culture are the most common means of identifying coccidioides spp. while these methods offer relatively sensitive and specific means of detecting coccidioides spp., growth in culture may take up to 3 weeks, potentially delaying the diagnosis and initiation of appropriate antifungal therapy. in addition, growth of the organism represents a significant ...200617108077
legionella dumoffii utilizes exogenous choline for phosphatidylcholine synthesis.phosphatidycholine (pc) is the major membrane-forming phospholipid in eukaryotes but it has been found in only a limited number of prokaryotes. bacteria synthesize pc via the phospholipid n-methylation pathway (pmt) or via the phosphatidylcholine synthase pathway (pcs) or both. here, we demonstrated that legionella dumoffii has the ability to utilize exogenous choline for phosphatidylcholine (pc) synthesis when bacteria grow in the presence of choline. the pcs seems to be a primary pathway for s ...201424821544
distribution of genes encoding nucleoid-associated protein homologs in plasmids.bacterial nucleoid-associated proteins (naps) form nucleoprotein complexes and influence the expression of genes. recent studies have shown that some plasmids carry genes encoding nap homologs, which play important roles in transcriptional regulation networks between plasmids and host chromosomes. in this study, we determined the distributions of the well-known naps fis, h-ns, hu, ihf, and lrp and the newly found naps mvat and ndpa among the whole-sequenced 1382 plasmids found in gram-negative b ...201121350637
rapid pcr detection of mycoplasma hominis, ureaplasma urealyticum, and ureaplasma parvum.objective. we compared laboratory developed real-time pcr assays for detection of mycoplasma hominis and for detection and differentiation of ureaplasma urealyticum and parvum to culture using genitourinary specimens submitted for m. hominis and ureaplasma culture. methods. 283 genitourinary specimens received in the clinical bacteriology laboratory for m. hominis and ureaplasma species culture were evaluated. nucleic acids were extracted using the total nucleic acid kit on the magna pure 2.0. 5 ...201326904723
a side by side comparison of bruker biotyper and vitek ms: utility of maldi-tof ms technology for microorganism identification in a public health reference laboratory.matrix-assisted laser desorption ionization-time of flight mass spectrometry (maldi-tof ms) has emerged as a rapid, highly accurate, and cost-effective method for routine identification of a wide range of microorganisms. we carried out a side by side comparative evaluation of the performance of bruker biotyper versus vitek ms for identification of a large and diverse collection of microorganisms. most difficult and/or unusual microorganisms, as well as commonly encountered microorganisms were se ...201526658918
armadillidin h, a glycine-rich peptide from the terrestrial crustacean armadillidium vulgare, displays an unexpected wide antimicrobial spectrum with membranolytic activity.antimicrobial peptides (amps) are key components of innate immunity and are widespread in nature, from bacteria to vertebrate animals. in crustaceans, there are currently 15 distinct amp families published so far in the literature, mainly isolated from members of the decapoda order. up to now, armadillidin is the sole non-decapod amp isolated from the haemocytes of armadillidium vulgare, a crustacean isopod. its first description demonstrated that armadillidin is a linear glycine-rich (47%) cati ...201627713732
the legionella pneumophila dot/icm-secreted effector plcc/cegc1 together with plca and plcb promotes virulence and belongs to a novel zinc metallophospholipase c family present in bacteria and fungi.legionella pneumophila is a water-borne bacterium that causes pneumonia in humans. plca and plcb are two previously defined l. pneumophila proteins with homology to the phosphatidylcholine-specific phospholipase c (pc-plc) of pseudomonas fluorescens. additionally, we found that lpg0012 shows similarity to plcs and has been shown to be a dot/icm-injected effector, cegc1, which is designated here as plcc. it remained unclear, however, whether these l. pneumophila proteins exhibit plc activity. plc ...201323457299
structure and functional characterization of pyruvate decarboxylase from gluconacetobacter diazotrophicus.bacterial pyruvate decarboxylases (pdc) are rare. their role in ethanol production and in bacterially mediated ethanologenic processes has, however, ensured a continued and growing interest. pdcs from zymomonas mobilis (zmpdc), zymobacter palmae (zppdc) and sarcina ventriculi (svpdc) have been characterized and zmpdc has been produced successfully in a range of heterologous hosts. pdcs from the acetobacteraceae and their role in metabolism have not been characterized to the same extent. examples ...201425369873
identification and biochemical characterization of an acid sphingomyelinase-like protein from the bacterial plant pathogen ralstonia solanacearum that hydrolyzes atp to amp but not sphingomyelin to ceramide.acid sphingomyelinase (asmase) is a human enzyme that catalyzes the hydrolysis of sphingomyelin to generate the bioactive lipid ceramide and phosphocholine. asmase deficiency is the underlying cause of the genetic diseases niemann-pick type a and b and has been implicated in the onset and progression of a number of other human diseases including cancer, depression, liver, and cardiovascular disease. asmase is the founding member of the asmase protein superfamily, which is a subset of the metallo ...201425144372
anti-legionella dumoffii activity of galleria mellonella defensin and apolipophorin iii.the gram-negative bacterium legionella dumoffii is, beside legionella pneumophila, an etiological agent of legionnaires' disease, an atypical form of pneumonia. the aim of this study was to determine the antimicrobial activity of galleria mellonella defense polypeptides against l. dumoffii. the extract of immune hemolymph, containing a mixture of defense peptides and proteins, exhibited a dose-dependent bactericidal effect on l. dumoffii. the bacterium appeared sensitive to a main component of t ...201223235329
detection of legionella bozemanae, a new cause of septic arthritis, by pcr followed by specific culture.legionella bozemanae is a rare isolate in clinical specimens. we describe a case of joint infection due to l. bozemanae in an immunocompromised patient with dermatomyositis. without the use of pcr screening or culture on specialized medium, the organism would not have been detected.201223052316
legionnaires' disease caused by legionella londiniensis.legionella londiniensis has been isolated from aqueous environments. however, to our knowledge, this organism has never been isolated from clinical specimens. a case of legionnaires' disease in a hematopoietic stem cell transplant recipient caused by this organism is described, which confirms that l. londiniensis can be an opportunistic pathogen.201223052303
draft genome sequences of two legionella dumoffii strains, tex-kl and ny-23.legionella (fluoribacter) dumoffii is one of the agents causing legionnaires' disease. here, we used illumina second-generation sequencing technology to decipher for the first time the whole-genome sequences of two strains of this species, tex-kl and ny-23. the assembly results for both strains consist of one chromosome and two plasmids.201222328752
identification and structural characterization of a legionella phosphoinositide phosphatase.bacterial pathogen legionella pneumophila is the causative agent of legionnaires' disease, which is associated with intracellular replication of the bacteria in macrophages of human innate immune system. recent studies indicate that pathogenic bacteria can subvert host cell phosphoinositide (pi) metabolism by translocated virulence effectors. however, in which manner legionella actively exploits pi lipids to benefit its infection is not well characterized. here we report that l. pneumophila enco ...201323843460
multiple legionella pneumophila type ii secretion substrates, including a novel protein, contribute to differential infection of the amoebae acanthamoeba castellanii, hartmannella vermiformis, and naegleria lovaniensis.type ii protein secretion (t2s) by legionella pneumophila is required for intracellular infection of host cells, including macrophages and the amoebae acanthamoeba castellanii and hartmannella vermiformis. previous proteomic analysis revealed that t2s by l. pneumophila 130b mediates the export of >25 proteins, including several that appeared to be novel. following confirmation that they are unlike known proteins, t2s substrates ntta, nttb, and legp were targeted for mutation. ntta mutants were i ...201323429532
high prevalence, genetic diversity and intracellular growth ability of legionella in hot spring environments.legionella is the causative agent of legionnaires' disease, and hot springs are a major source of outbreaks of this disease. it is important from a public health perspective to survey hot spring environments for the presence of legionella.201323527075
computational modeling and experimental validation of the legionella and coxiella virulence-related type-ivb secretion signal.legionella and coxiella are intracellular pathogens that use the virulence-related icm/dot type-ivb secretion system to translocate effector proteins into host cells during infection. these effectors were previously shown to contain a c-terminal secretion signal required for their translocation. in this research, we implemented a hidden semi-markov model to characterize the amino acid composition of the signal, thus providing a comprehensive computational model for the secretion signal. this mod ...201323382224
identification of legionella spp. in environmental water samples by scanvit-legionella™ method in spain.rapid and more sensitive methods for the detection and quantification of viable legionella cells have been developed. in this paper, a comparative analysis of environmental water samples using the scanvit-legionella™ method and the traditional "gold standard" method of culturing is realised indicating the usefulness of the scanvit method. the scanvit-legionella™ method was performed on environmental water samples from different locations of huesca region (spain). legionella micro-colonies should ...201324426100
a new oligonucleotide microarray for detection of pathogenic and non-pathogenic legionella spp.legionella pneumophila has been recognized as the major cause of legionellosis since the discovery of the deadly disease. legionella spp. other than l. pneumophila were later found to be responsible to many non-pneumophila infections. the non-l. pneumophila infections are likely under-detected because of a lack of effective diagnosis. in this report, we have sequenced the 16s-23s rrna gene internal transcribed spacer (its) of 10 legionella species and subspecies, including l. anisa, l. bozemanii ...201425469776
two fis regulators directly repress the expression of numerous effector-encoding genes in legionella pneumophila.legionella pneumophila is an intracellular human pathogen that utilizes the icm/dot type ivb secretion system to translocate a large repertoire of effectors into host cells. for most of these effectors, there is no information regarding their regulation. therefore, the aim of this study was to examine the involvement of the three l. pneumophila fis homologs in the regulation of effector-encoding genes. deletion mutants constructed in the genes encoding the three fis regulators revealed that fis1 ...201425225276
comparative analyses of legionella species identifies genetic features of strains causing legionnaires' disease.the genus legionella comprises over 60 species. however, l. pneumophila and l. longbeachae alone cause over 95% of legionnaires’ disease. to identify the genetic bases underlying the different capacities to cause disease we sequenced and compared the genomes of l. micdadei, l. hackeliae and l. fallonii (llap10), which are all rarely isolated from humans.201425370836
native structure of a type iv secretion system core complex essential for legionella pathogenesis.bacterial type iv secretion systems are evolutionarily related to conjugation systems and play a pivotal role in infection by delivering numerous virulence factors into host cells. using transmission electron microscopy, we report the native molecular structure of the core complex of the dot/icm type iv secretion system encoded by legionella pneumophila, an intracellular human pathogen. the biochemically isolated core complex, composed of at least five proteins--dotc, dotd, dotf, dotg, and doth- ...201425062693
legionellosis outbreak associated with a hotel fountain.background.  in august 2012, the chicago department of public health (cdph) was notified of acute respiratory illness, including 1 fatality, among a group of meeting attendees who stayed at a chicago hotel during july 30-august 3, 2012. suspecting legionnaires' disease (ld), cdph advised the hotel to close their swimming pool, spa, and decorative lobby fountain and began an investigation. methods.  case finding included notification of individuals potentially exposed during july 16-august 15, 20 ...201526716104
microbiological and clinical studies of legionellosis in 33 patients with cancer.legionella, a large group of environmental gram-negative bacteria, represents an occasional cause of pneumonia. we analyzed the microbiological and clinical features of 33 consecutive cases of legionella infections that occurred at the university of texas md anderson cancer center, houston, tx, from 2002 to 2014. the legionella strains were isolated from bronchoscopy specimens (32 strains) and a blood culture (1 strain) and were identified by sequencing analysis of the full-length 16s rrna gene. ...201525926494
lpg0393 of legionella pneumophila is a guanine-nucleotide exchange factor for rab5, rab21 and rab22.legionella pneumophila, a human intracellular pathogen, encodes about 290 effector proteins that are translocated into host cells through a secretion machinery. some of these proteins have been shown to manipulate or subvert cellular processes during infection, but functional roles of a majority of them remain unknown. lpg0393 is a newly identified legionella effector classified as a hypothetical protein. through x-ray crystallographic analysis, we show that lpg0393 contains a vps9-like domain, ...201525821953
molecular characterization of viable legionella spp. in cooling tower water samples by combined use of ethidium monoazide and pcr.viable legionella spp. in environmental water samples were characterized phylogenetically by a clone library analysis combining the use of ethidium monoazide and quantitative pcr. to examine the diversity of legionella spp., six cooling tower water samples and three bath water samples were collected and analyzed. a total of 617 clones were analyzed for their 16s rrna gene sequences and classified into 99 operational taxonomic units (otus). the majority of otus were not clustered with currently d ...201525736979
diverse mechanisms of metaeffector activity in an intracellular bacterial pathogen, legionella pneumophila.pathogens deliver complex arsenals of translocated effector proteins to host cells during infection, but the extent to which these proteins are regulated once inside the eukaryotic cell remains poorly defined. among all bacterial pathogens, legionella pneumophila maintains the largest known set of translocated substrates, delivering over 300 proteins to the host cell via its type ivb, icm/dot translocation system. backed by a few notable examples of effector-effector regulation in l. pneumophila ...201627986836
mtor-driven metabolic reprogramming regulates legionella pneumophila intracellular niche homeostasis.vacuolar bacterial pathogens are sheltered within unique membrane-bound organelles that expand over time to support bacterial replication. these compartments sequester bacterial molecules away from host cytosolic immunosurveillance pathways that induce antimicrobial responses. the mechanisms by which the human pulmonary pathogen legionella pneumophila maintains niche homeostasis are poorly understood. we uncovered that the legionella-containing vacuole (lcv) required a sustained supply of host l ...201627942021
legionella pneumophila: the paradox of a highly sensitive opportunistic waterborne pathogen able to persist in the environment.legionella pneumophila, the major causative agent of legionnaires' disease, is found in freshwater environments in close association with free-living amoebae and multispecies biofilms, leading to persistence, spread, biocide resistance, and elevated virulence of the bacterium. indeed, legionellosis outbreaks are mainly due to the ability of this bacterium to colonize and persist in water facilities, despite harsh physical and chemical treatments. however, these treatments are not totally efficie ...201627092135
population structure and minimum core genome typing of legionella pneumophila.legionella pneumophila is an important human pathogen causing legionnaires' disease. in this study, whole genome sequencing (wgs) was used to study the characteristics and population structure of l. pneumophila strains. we sequenced and compared 53 isolates of l. pneumophila covering different serogroups and sequence-based typing (sbt) types (sts). we found that 1,896 single-copy orthologous genes were shared by all isolates and were defined as the minimum core genome (mcg) of l. pneumophila. a ...201626888563
prions and dentistry. 200211934906
screening and identification of dnaj interaction proteins in streptococcus pneumoniae.streptococcus pneumoniae dnaj is recognized as a virulence factor whose role in pneumococcal virulence remains unclear. here, we attempted to reveal the contribution of dnaj in pneumococcal virulence from the identification of its interacting proteins using co-immunoprecipitation method. dnaj was cloned into plasmid pae03 generating pae03-dnaj-gfp which was used to transform s. pneumoniae d39 strain. then anti-gfp coated beads were used to capture gfp-coupled proteins from the bacterial lysate. ...201323907491
cytokine production assays reveal discriminatory immune defects in adults with recurrent infections and noninfectious inflammation.cytokine production assays have been primarily used in research settings studying novel immunodeficiencies. we sought to determine the diagnostic value of cytokine production assays in patients with recurrent and/or severe infectious diseases (ids) without known immunodeficiencies and unclassified noninfectious inflammatory disorders (niids). we retrospectively examined cytokine production in whole-blood and peripheral blood mononuclear cell samples from 157 adult patients. a cytokine production ...201424872512
distribution of secretion systems in the genus legionella and its correlation with pathogenicity.the genus legionella comprises over 60 species, which are important human pathogens. secretion systems in legionella pneumophila have been studied extensively because of the essential role of protein secretion in bacterial infection. however, there are few reports describing the secretion systems in non-l. pneumophila species. in this study, we analyzed the distribution of secretion systems in l. pneumophila and 18 species of non-l. pneumophila based on whole genome sequences. a total of 74 whol ...201728352254
bacterial secretion system skews the fate of legionella-containing vacuoles towards lc3-associated phagocytosis.the evolutionarily conserved processes of endosome-lysosome maturation and macroautophagy are established mechanisms that limit survival of intracellular bacteria. similarly, another emerging mechanism is lc3-associated phagocytosis (lap). here we report that an intracellular vacuolar pathogen, legionella dumoffii, is specifically targeted by lap over classical endocytic maturation and macroautophagy pathways. upon infection, the majority of l. dumoffii resides in er-like vacuoles and replicate ...201728317932
legionella dumoffii tex-kl mutated in an operon homologous to trac-trad is defective in epithelial cell invasion.to understand the mechanism of invasion by legionella dumoffii.201627470103
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