Legionella

Legionella is a Gram negative bacterium, including species that cause legionellosis or Legionnaires' disease, most notably L. pneumophilia. Legionella are common in many environments, with at least 50 species and 70 serogroups identified. The side-chains of the cell wall carry the bases responsible for the somatic antigen specificity of these organisms. The chemical composition of these side chains both with respect to components as well as arrangement of the different sugars determines the nature of the somatic or O antigen determinants, which are essential means of serologically classifying many Gram-negative bacteria.
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Legionella /Le·gion·el·la/ a genus of gram-negative, aerobic, rod-shaped bacteria, normal inhabitants of lakes, streams, and moist soil; they have [more]Legionella - Community and Resources

Noun
1. the motile aerobic rod-shaped Gram-negative bacterium that thrives in centralheating and air conditioning systems and can cause Legionnairs' disease
(synonym) Legionella pneumophilia
(hypernym) bacteria, bacterium

n. legionella

The bacteria causing Legionaire's disease.