ABSTRACT
Since the initial isolation of Legionella pneumophila by McDade et al. using guinea pigs and embryonated hens' eggs, several artificial media have been developed that support the growth of the organism. Since L. pneumophila has been recovered from water in cooling towers and evaporative condensers of buildings associated with cases of Legionnaires' disease, the susceptibility of the agent to certain biocides was studied. The initial biochemical studies with L. pneumophila were performed primarily for the purpose of clinical isolation and identification, as well as specific taxonomic classification. The original biochemical characterizations of L. pneumophila demonstrated gelatinase and ß-lactamase production, as well as starch hydrolysis. Since the initial discovery of L. pneumophila, much has been learned about the physiology and metabolism of this organism. However, there is still much to be understood concerning the genetics of L. pneumophila. Most of the published genetic work on the Legionellaceae has dealt with plasmids.
