What are the recognized species of the genus Listeria?

Abstract

Listeria is an important food-borne pathogen that affects the elderly, pregnant women, neonates and immunecompromised persons. In the last decade, there has been an increase in identification of new species from diverse sources, but Listeria monocytogenes remains the main pathogenic species of the genus. In recent times, investigators have reported different numbers of species for the genus; hence, it is important to clarify the number of species available now. A recent article [1] reported that the genus Listeria comprises up to 21 species. The authors relied on the information in the List of Prokaryotic Names with Standing in Nomenclature at the ' Bacterio. net' website (http://www. bacterio. net/ listeria. html) to conclude 21 species. A closer perusal of the information on this site shows that some species taxonomy details were revised many years ago. The most pathogenic, L. monocytogenes, was originally described in 1926, but assigned the name in 1940 [2]. Although 22 species are listed, 2 species, namely Listeria denitrificans and Listeria murrayi, are shown to be synonyms. The species L. denitrificans was transferred to a new genus and renamed Jonesia denitrificans in 1987 [3] and has since been confirmed by two recent emendations [4, 5]. It was later found that high-level similarities exist between Listeria grayi and L. murrayi when a re-evaluation was carried out by Rocourt et al. [6] using several methods that included DNA-DNA hybridization, multilocus enzyme electrophoresis and rRNA restriction fragment length polymorphism. Hence, both were merged to a single species, L. grayi, as a matter of priority. The emended strain can be obtained using the designation ATCC 25401 [7]. The 2oth species described is Listeria thailandensis by Leclercq et al. [8] and they acknowledged 19 species existed before they described the new species. This is the last entry made in the International Journal of Systematic and Evolutionary Microbiology, the leading forum for the publication of novel microbial taxa and the International Committee on Systematics of Prokaryotes (ICSP) official journal record for prokaryotic names. The 20 species reviewed (Table 1) are the most up to date count of the number of Listeria species and not 21.

Listeria Necrotizing Cellulitis: A Case Report

“…The skin started to appear necrotic, with a major change in color to green-grey and oozing of malodorous pus and several ulcerations (figure 1B Listeria is an important foodborne pathogen that affects pregnant women, the elderly, neonates, and immunocompromised persons. In the last decade, new species have been identified from diverse sources, with recent reports indicating that the genus Listeria now comprises up to 21 species [1]. Listeria monocytogenes was originally described in 1926 as the cause of an epizootic outbreak in rabbits and guinea pigs, and later assigned its name in 1940.…”

“…Listeria is a genus of gram-positive bacteria that are the causative agents of human Listeriosis. Although L. monocytogenes is the main pathogenic species, there are a total of 21 described species including L. grayi which was previously divided into L. grayi and L. murrayi [1]. L. monocytogenes typically affects pregnant women, neonates, or immunocompromised individuals, with a wide clinical spectrum that includes Central Nervous System (CNS) infections, endocarditis, and very rarely, localized infections such as necrotizing fasciitis [2,3].…”

Targeting PrfA from Listeria monocytogenes: a computational drug repurposing approach

“…Listeria monocytogenes ( L. monocytogenes ) is a facultative anaerobic, ubiquitous gram-positive bacterium with a remarkable ability to grow at low temperatures and to resist low water activity, low pH and high salt environments [1,2]. L. monocytogenes is also capable of forming biofilms, which further helps the microorganism withstand the most harsh environments [3].…”

Antimicrobial Resistance of Listeria monocytogenes from Animal Foods to First- and Second-Line Drugs in the Treatment of Listeriosis from 2008 to 2021: A Systematic Review and Meta-Analysis

“…Listeria genus comprises of twenty-one species, such as L. grayi, L. innocua, L. ivanovii, L. monocytogenes, L. seeligeri, and L. welshimeri, among others [1]. Among them, only L. monocytogenes (Listeria monocytogenes) is considered pathogenic to humans and other animals [2] being implicated in severe cases of sepsis, encephalitis, meningitis, and abortions, with high rates of hospitalization and death [3].…”