Coxiella burnetii is a highly infectious bacterium that promotes its own replication in macrophages by inhibiting several host cell responses. Here, we show that C. burnetii inhibits caspase-1 activation in primary mouse macrophages. By using co-infection experiments, we determine that the infection of macrophages with C. burnetii inhibits the caspase-11-mediated non-canonical activation of the...

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 inte...

The synthesis of a global stress protein (GspA) of Legionella pneumophila is induced in the intracellular environment of the phagocytic ceil and by various in vitro stress stimuli. We used techniques of reverse genetics to isolate the gspA gene from a genomic library of L. pneumophila. Sequence analysis of approximately 1700 bp of a representative clone (pBSP1) showed the presence of two open r...

In addition to Legionella pneumophila, 19 Legionella species have been documented as human pathogens on the basis of their isolation from clinical material. Like L. pneumophila, other Legionella species are inhabitants of natural and man-made aqueous environments. The major clinical manifestation of infection due to Legionella species is pneumonia, although nonpneumonic legionellosis (Pontiac f...

We compared a fluorescein-labeled monoclonal antibody directed against an outer membrane protein of Legionella pneumophila (Genetic Systems Corp. [GSC], Seattle, Wash.) with a similarly labeled polyclonal reagent (L. pneumophila serogroups 1 to 6, poly; BioDx, Inc., Denville, N.J.) for the confirmation of L. pneumophila isolates grown in culture. Duplicate suspensions of 52 organisms, including...

A monoclonal antibody (MAb) immunoglobulin G2a (2125) was produced against a 60-kDa Legionella heat shock protein (HSP), recognizing a unique epitope common to all species of the genus Legionella. The antibody reacted in the immunoblot with 59 Legionella species and serogroups that were tested and showed no cross-reactivity with other bacteria, including Acinetobacter spp., Bordetella spp., Pse...

Legionnaires' disease is clinically manifested as severe pneumonia caused by Legionella pneumophila. However, the dendritic cell (DC)-centered immunological framework of the host defense against L. pneumophila has not been fully delineated. For this study, we focused on a potent chemoattractant for lymphocytes, fractalkine/CX3CL1, and observed that the fractalkine expression of DCs was somewhat...

<i>Legionella </i>spp<i>.</i> are the etiological agent of legionnaire’s disease, a severe respiratory which affects mostly vulnerable groups population. In present study, we investigated presence <i>Legionella</i> according to ISO 11731:2017 in water samples, collected from five regions Northern Greece. The results showed that 64 (8.9%) out 595 samples were ...

A boron-doped diamond (BDD) electrode was constructed as a water disinfector for the inactivation of water borne pathogens. The bactericidal effect of the disinfector was evaluated on artificially contaminated waters containing, respectively, Escherichia coli, Pseudomonas aeruginosa and Legionella pneumophila at high density. By treating the bacterial suspensions with 4 V of constant voltage be...

Legionella pneumophila, the causative agent of Legionnaires' disease, replicates within alveolar macrophages and free-living amoebae. However, the lifestyle of L. pneumophila in the environment remains largely unknown. Here we established a novel natural host model of L. pneumophila endosymbiosis using the ciliate Paramecium caudatum. We also identified Legionella endosymbiosis-modulating facto...