BACKGROUND Legionnaires' disease continues to be a public health concern in passenger ships. This study was scheduled in order to investigate Legionella spp. colonization of water distribution systems (WDS), recreational pools, and air-conditioning systems on board ferries and cruise ships in an attempt to identify risk factors for Legionella spp. colonization associated with ship water systems...

LBM415 activity against extracellular and intracellular Legionella pneumophila was studied. The LBM415 MIC50 for 20 Legionella sp. strains was 4 microg/ml, versus 0.06, 0.25, and <or=0.03 microg/ml for azithromycin, erythromycin, and levofloxacin, respectively. LBM415 (0.5 and 16 microg/ml) reversibly prevented intracellular growth of two L. pneumophila strains and was less active than erythrom...

The mechanisms by which Legionella pneumophila, a facultative intracellular parasite and the agent of Legionnaires' disease, acquires iron are largely unexplained. Several earlier studies indicated that L. pneumophila does not elaborate siderophores. However, we now present evidence that supernatants from L. pneumophila cultures can contain a nonproteinaceous, high-affinity iron chelator. More ...

Aim: Since culture method is time-consuming and has low sensitivity, we developed a duplex PCR (dPCR) assay for the detection of Legionella sp. and L. pneumophila in cooling tower samples. We used culture method as a gold standard. Methods: Optimization of dPCR method was performed to obtain an assay with high sensitivity and specifi city. The optimized method was used to detect Legionella sp. ...

The activities of HMR 3647, HMR 3004, erythromycin, clarithromycin, and levofloxacin for 97 Legionella spp. isolates were determined by microbroth dilution susceptibility testing. Growth inhibition of two Legionella pneumophila strains grown in guinea pig alveolar macrophages was also determined. The concentrations required to inhibit 50% of strains tested were 0.06, 0.02, 0.25, 0.03, and 0.02 ...

Legionella pneumophila is the causative agent of human Legionnaires' disease. L. pneumophila has been shown to induce apoptosis of T-cells and this may be important pathologically and clinically. The present study has determined the molecular mechanisms underlying L. pneumophila-induced apoptosis, which were unclear. Wild-type L. pneumophila and flagellin-deficient Legionella, but not L. pneumo...

Ten serogroups of Legionella pneumophila have now been described.' Although the direct fluorescent antibody technique is widely used to identify and serologically differentiate L pneumophila isolates,2 some cross reactivity between serogroups3 and some staining of non-legionella organisms with legionella antisera4 have been reporrea. Several simple alternatives to the direct fluorescent antibod...

Legionella pneumophila expresses two catalase-peroxidase enzymes that exhibit strong peroxidatic but weak catalatic activities, suggesting that other enzymes participate in decomposition of hydrogen peroxide (H2O2). Comparative genomics revealed that L. pneumophila and its close relative Coxiella burnetii each contain two peroxide-scavenging alkyl hydroperoxide reductase (AhpC) systems: AhpC1, ...

legionella pneumophila, the causative agent of legionnaires’ diseases (ld) is usually transmitted to humans via inhalation of aerosols from contaminated natural and manmade water sources. these organisms may become fatal especially in immunocompromised patients and ld is the one of the important disease from a public health perspective. this survey investigated the frequency of legionella spp. ...

We evaluated the in vitro susceptibility of Legionella pneumophila ATCC 33152 (serogroup I) to 13 antibiotics alone and in combination with rifampin (0.1 mg/liter) by three methods. Extracellular susceptibility was determined by MIC determinations and time kill curves in buffered yeast extract broth, while intracellular susceptibility was determined by peripheral human monocytes in RPMI 1640 cu...