Image of Legionella pneumophila

Description:

Under a moderately-high magnification of 10000X, this scanning electron micrograph (SEM) depicted a number of Gram-negative Legionella pneumophila bacteria. Please see PHIL 11092 through 11152 for additional SEMs of these organisms, specifically PHIL 11138 for a colorized version of this image. Of particular importance, is the presence of polar flagella, and pili, or long streamers, which due to their fragile nature, in some of these views seem to be dissociated from any of the bacteria. For a better view of these cellular appendages, see the colorized version.

You’ll note that a number of these bacteria seem to display an elongated-rod morphology. L. pneumophila are known to most frequently exhibit this configuration when grown in broth, however, they can also elongate when plate-grown cells age, as it was in this case, especially when they’ve been refrigerated.
Created: 2009