Characterization of surfaces involved in adherence of Legionella pneumophila to Fischerella species.

Legionella pneumophila adheres to the slime coat of Fischerella spp. This was shown by microscopic examination and by a decline in L. pneumophila CFU in samples removed from coincubation mixtures of both organisms. Binding of partially purified Fischerella slime by L. pneumophila was most efficient by young, less hydrophobic L. pneumophila cells than by older, more hydrophobic cells. Uptake of crystal violet and partitioning into hexadecane were used to measure hydrophobicity of L. pneumophila. Purified soluble Legionella antigen also bound to Fischerella slime, as shown by indirect immunofluorescence. Adherence was not specific for L. pneumophila, since a variety of gram-negative, gram-positive, and acid-fast bacteria also bound to Fischerella slime.