ABSTRACT
In 1924, E.G.D. Murray isolated Gram-positive rods from the blood of laboratory rabbits with peripheral monocytosis, and because he could not assign these microorganisms to any bacterial genus known at that time, he identied them as Bacterium monocytogenes (Murray et al. 1926). In 1927, Pirie isolated a Grampositive bacterium from gerbils and suggested the genus Listerella for these organisms (Pirie 1940a). Both researchers independently deposited their cultures in the National Type Collection of the Lister Institute in London, where it was determined that the two organisms were the same. Murray and Pirie agreed to call the organism Listerella monocytogenes (Murray 1953) but the International Committee on Systematic Bacteriology rejected the genus name Listerella and so Pirie subsequently changed the genus name to Listeria (Pirie 1940b). The genus Listeria currently contains 10 species: L. fleischmannii, L. grayi, L. innocua, L. ivanovii, L. marthii, L. monocytogenes, L. rocourtiae, L. seeligeri, L. weihenstephanensis, and L. welshimeri (Collins et al. 1991). L. monocytogenes causes a severe foodborne disease in humans (den Bakker et al. 2010) and thus is of particular interest to food manufacturers.
