Listeriaceae

The Listeriaceae are a family of Gram-positive bacteria that includes two genera: Listeria and Brochothrix.  They are short, rod-shaped bacteria that are aerobic or facultatively anaerobic. Spores are not formed, but under stress these bacteria can form filaments. Some species, namely Listeria monocytogenes, can cause human and animal listeriosis. While not all bacteria in the Listeriaceae family are considered a danger to humans, some are strongly associated with food borne illness or microbial spoilage, so they remain a topic of interest in agricultural industries.