Characteristics and distribution of Listeria spp., including Listeria species newly described since 2009

Abstract

The genus Listeria is currently comprised of 17 species, including 9 Listeria species newly described since 2009. Genomic and phenotypic data clearly define a distinct group of six species (Listeria sensu strictu) that share common phenotypic characteristics (e.g., ability to grow at low temperature, flagellar motility); this group includes the pathogen Listeria monocytogenes. The other 11 species (Listeria sensu lato) represent three distinct monophyletic groups, which may warrant recognition as separate genera. These three proposed genera do not contain pathogens, are non-motile (except for Listeria grayi), are able to reduce nitrate (except for Listeria floridensis), and are negative for the Voges-Proskauer test (except for L. grayi). Unlike all other Listeria species, species in the proposed new genus Mesolisteria are not able to grow below 7 °C. While most new Listeria species have only been identified in a few countries, the availability of molecular tools for rapid characterization of putative Listeria isolates will likely lead to future identification of isolates representing these new species from different sources. Identification of Listeria sensu lato isolates has not only allowed for a better understanding of the evolution of Listeria and virulence characteristics in Listeria but also has practical implications as detection of Listeria species is often used by the food industry as a marker to detect conditions that allow for presence, growth, and persistence of L. monocytogenes. This review will provide a comprehensive critical summary of our current understanding of the characteristics and distribution of the new Listeria species with a focus on Listeria sensu lato.

Listerial mesenteric lymphadenitis in 3 cats

“…There has been at least 1 report of Listeria grayi contamination of pet jerky treats and dry cat food, and although this nonpathogenic Listeria species is not implicated in foodborne disease, the detection of a nonpathogenic Listeria spp. acts as an indicator of conditions appropriate for the presence and growth of Lm . Thus, there is also the potential for commercially processed pet foods to act as the source of Lm infection.…”

Strain-level typing and identification of bacteria – a novel approach for SERS active plasmonic nanostructures

“…L. monocytogenes , one out of 17 species qualified to Listeria genus, is an important foodborne pathogen [18] that can cause serious human infections, such as bacteremia and central nervous system infections, primarily in neonates and immunocompromised adults. It can also cause perinatal infections that may result e.g., in abortions [19].…”

Main Groups of Microorganisms of Relevance for Food Safety and Stability

“…This genus includes 17 species: L. monocytogenes, L. ivanovii, L. aquatica, L. booriae, L. cornellensis, L. fleischmannii, L. floridensis, L. grandensis, L. grayi, L. innocua, L. marthii, L. newyorkensis, L. riparia, L. rocourtiae, L. seeligeri, L. weihenstephanensis, and L. welshimeri. However, only L. monocytogenes and L. ivanovii are considered pathogens to humans (Orsi & Wiedmann, 2016). The main suggested niches for Listeria species are soil and water although plants, animals (particularly farm animals), and man are also considered as reservoirs of Listeria spp.…”