The Molecular Virulence of Legionnaires' Disease Bacterium.

Legionella pneumophila, a facultative intracellular pathogen is responsible for almost 85% of cases of the legionelloses Legionnaires' disease and Pontiac fever (Dowling et al., 1992; Fields, 1997). These are a consequence of the fact that man has created additional environmental reservoirs for these opportunistic pathogens, providing them with a means by which they can be disseminated in aerosols and exposed to humans (Fields, 1997; Shuman et al., 1998). While both forms of legionellosis are caused by inhalation of adequate numbers …

…la are waiting to be identified in the near future, not only from the remaining DNA hybridisation groups but also by other approaches. At present a situation exists whereby genes indispensable for intracellular multiplication seem to code for novel proteins. Perhaps the discovery of these additional genetic factors promoting virulence, and more advanced topological analysis of these and existing gene products may hold the key to realising the actual nature of a multiprotein membrane complex.