Listeria monocytogenes is the species of pathogenic bacteria that causes the infection listeriosis. It is a facultative anaerobic bacterium, capable of surviving in the presence or absence of oxygen. It can grow and reproduce inside the host's cells and is one of the most virulent foodborne pathogens. Twenty to thirty percent of foodborne listeriosis infections in high-risk individuals may be fatal. In the European Union, listeriosis continues an upward trend that began in 2008, causing 2,161 confirmed cases and 210 reported deaths in 2014, 16% more than in 2013. In the EU, listeriosis mortality rates also are higher than those of other foodborne pathogens. Responsible for an estimated 1,600 illnesses and 260 deaths in the United States annually, listeriosis ranks third in total number of deaths among foodborne bacterial pathogens, with fatality rates exceeding even Salmonella spp. and Clostridium botulinum.
Listeria is a genus of bacteria that acts as an intracellular parasite in mammals. By 2024, 28 species had been identified. The genus is named in honour of the British pioneer of sterile surgery Joseph Lister. Listeria species are Gram-positive, rod-shaped, and facultatively anaerobic, and do not produce endospores.
Sphaeropleales is an order of green algae that used to be called Chlorococcales. The order includes some of the most common freshwater planktonic algae such as Scenedesmus and Pediastrum. The Sphaeropleales includes vegetatively non-motile unicellular, colonial, or filamentous taxa. They have biflagellate zoospores with flagella that are directly opposed in direction : Sphaeroplea, Atractomorpha, Neochloris, Hydrodictyon, and Pediastrum. All of these taxa have basal body core connections. Motile cells generally lack cell walls or have only a very fine layer surrounding the cell membrane. Other common characteristics include a robust vegetative cell wall, cup-shaped chloroplasts with large pyrenoids, and relatively large nuclei.
Listeria marthii is a species of bacteria. It is a Gram-positive, motile, facultatively anaerobic, non-spore-forming bacillus. It is non-pathogenic, and non-hemolytic. The species was first isolated from Finger Lakes National Forest in New York. It is named after Elmer H. Marth, a researcher of L. monocytogenes, and was first published in 2010. L. marthii was the first new species of Listeria proposed since 1985.
Listeria rocourtiae is a species of bacteria. It is a Gram-positive, facultatively anaerobic, motile, non-spore-forming bacillus. It is non-pathongenic and non-hemolytic. The species was first isolated from pre-cut lettuce in Salzburg, Austria in 2002. It is named in honor of Jocelyne Rocourt, "whose work had a major impact on the taxonomy of the genus Listeria."
Caballeronia humi is a Gram-negative, aerobic, non-motile bacterium from the genus Burkholderia and the family Burkholderiaceae which was isolated from peat soil in Russia.
Listeria aquatica is a Gram-positive, facultatively anaerobic, nonmotile, non-spore-forming rod-shaped species of bacteria. It is not pathogenic. It was discovered from running water in Florida, and was first described in 2014. Its name comes from Latin, "found in water, aquatic".
Listeria riparia is a species of bacteria. It is a Gram-positive, facultatively anaerobic, non-motile, non-spore-forming bacillus. It is non-pathongenic. Its name refers to the riparian zone, and its discovery was first published in 2014.
Listeria cornellensis is a species of bacteria. It is a Gram-positive, facultatively anaerobic, non-motile, non-spore-forming bacillus. It is non-pathogenic. The species was named after Cornell University, and its discovery was first published in 2014.
Listeria grandensis is a species of bacteria. It is a Gram-positive, facultatively anaerobic, non-motile, non-spore-forming bacillus. It is non-pathongenic and non-hemolytic. The species was discovered in and named after Grand County, Colorado, and its discovery was first published in 2014.
Listeria booriae is a Gram-positive, facultatively anaerobic, nonmotile, non-spore-forming rod-shaped species of bacteria. It is not pathogenic and nonhemolytic. It was discovered in a dairy processing plant in the Northeastern United States, and was first described in 2015. The species name honors "Kathryn Boor, a United States food scientist, for her contribution to the understanding of the biology of Listeria."
Listeria newyorkensis is a species of bacteria. It is a Gram-positive, facultatively anaerobic, non-motile, non-spore-forming bacillus. It is non-pathogenic and non-hemolytic. It was discovered in a seafood processing plant in New York, and was first published in 2015.
Listeria weihenstephanensis is a species of bacteria. It is a Gram-positive, facultatively anaerobic, non-motile, non-spore-forming bacillus. It is non-pathongenic and non-hemolytic. It was discovered in a Lemna trisulca plant in a pond in Bavaria, Germany. The species name reflects the region in which it was first isolated, and was first published in 2013.
Listeria fleischmannii is a species of bacteria. It is a Gram-positive, facultatively anaerobic, non-motile, non-spore-forming bacillus. It is non-pathogenic and non-hemolytic. The species was first isolated in 2006 in Switzerland from hard cheese. The species is named after Wilhelm Fleischmann, a pioneer in the research of dairy products.
Listeria welshimeri is a species of bacteria. It is a Gram-positive, facultatively anaerobic, motile, non-spore-forming bacillus. It is non-pathogenic and non-hemolytic. It was isolated from decayed vegetation in the United States by H. J. Welshimer, after whom the species is named. The species was first proposed in 1983.
Listeria seeligeri is a Gram-positive, facultatively anaerobic, motile, nonspore-forming, bacillus-shaped species of bacteria. It is not pathogenic. The species was first isolated from plants, soil, and animal feces in Europe, was first proposed in 1983, and is named after Heinz P. R. Seeliger. Seeliger first proposed the species L. ivanovii and L. innocua, and published extensively on members of the genus Listeria.
Listeria grayi is a species of bacteria. It is a Gram-positive, facultatively anaerobic, motile, non-spore-forming bacillus. It is non-hemolytic. The species was first proposed in 1966. It is named after M.L. Gray, an early researcher in L. monocytogenes There are two subspecies of L. grayi: L. gray subs. grayi, and L. grayi subsp. murrayi.
Listeria thailandensis is a species of bacteria. It is a Gram-positive, facultatively anaerobic, non-motile, non-spore-forming bacillus. It is non-pathogenic and non-hemolytic. It was isolated from a fried chicken sample from Thailand. The species was first proposed in 2019, and the species name refers to the country from which it was first isolated.
'Listeria goaensis' is a new species identified under the genus Listeria. The type strain of the species was isolated from the sediment of estuarine mangrove swamp of the Mandovi river, Goa, India. The species shows weak hemolysis on 5% sheep and horse-blood agar plates.
Listeria innocua is a species of Gram-positive, rod-shaped bacteria. It is motile, facultatively anaerobic, and non-spore-forming. L. innocua was named innocua (innocuous) because, in contrast to Listeria monocytogenes, it does not readily cause disease in mammals. Another Listeria species, L. seeligeri, was named after one of the discoverers of L. innocua.
