Live tularemia vaccine confers protection against lethal Legionella and Listeria infections in experimental animals.

The efficacy of a live Francisella tularensis vaccine strain to cause nonspecific immunity toward experimental legionellosis and listeriosis was studied. Immunisation with tularemia vaccine protected over 80% and 17% of experimental animals against subsequent lethal challenge with Legionella pneumophila and Listeria monocytogenes, respectively. The protection was maximal during the first month following immunisation and declined thereafter.

Purification and characterization of a 58-kDa cell wall-associated protein from Listeria monocytogenes.

A cell wall protein (P58) was purified from Listeria monocytogenes by detergent extraction and Superose 6 gel chromatography. It had a molecular mass of 58 kDa, was strongly hydrophobic, contained reactive thiol group(s) and was located at least partially on the surface of bacterial cells. Production of this protein varied among different Listeria, being the most prominent in NCTC 7973 of L.

Purification and characterization of cell wall proteins of Listeria monocytogenes.

Two proteins were purified from Listeria monocytogenes cell wall using detergent extraction, Superose 6 gel chromatography. Mono Q cation-exchange chromatography and Superose 12 gel chromatography. Proteins were shown to form complexes of ca.

ADP-ribosyltransferase activity of Legionella pneumophila is stimulated by the presence of macrophage lysates.

ADP-ribosyltransferases are among the most biologically active of bacterial products in eukaryotes, and act by transferring the ADP-ribosyl moiety of NAD to acceptor proteins. The detection of ADP-ribosylated Legionella proteins in ultrasonic lysates of Legionella pneumophila strain Philadelphia 1 is reported. The ADP-ribosylating reaction was not influenced by addition of guinea pig spleen-cell and lung-cell lysates, but was considerably increased in the presence of lysates of guinea pig peritoneal macrophages, which are known to be target cells for virulent Legionella.

Signal transduction in eukaryotic cells and intracellular parasitism of Legionella.

A fundamental property of the eukaryotic cell is its ability to respond to external signals. This property becomes extremely important during microbial invasion, when the volume of information to be analyzed by the cellular receptor machinery increases considerably. Cell-surface receptors are influenced by a pool of additional ligands, some of the most important of these being the infecting microorganism, products of bacterial metabolism, virulence factors, as well as regulators produced by the endocrine and immune systems of the infected animal (e.