|| Listeria monocytogenes|
||Genus name: named after the British surgeon Lord Lister. Species epithet: monocyte producing.|
|Significance:|| [Very important]
||ATCC 15313 = NCTC 10357.|
|Small (0,5- 1 mm in diameter) colonies, which can be crateriform on certain selective media. Produces a zone of hemolysis on blood agar.
||Long thin rods (0.4-0.5 x 0.5-2 µm) in short chains. Motile by means of a few peritrichous flagella.
|Gram +/Gram -:||G+
||Esculinase +, lecithinase +, β-D-glucosidase +, hippuricase +, tryptophanase -, urease -.
||Methyl red +, Voges-Proskauer +.
|Fermentation of carbohydrates:
Other carbohydrates: Galactose v, ribose -, xylitol +, xylose -.
||Psychrotrophic. Can grow at 0-42°C and has temperature optimum at 30°C. Can survive at high NaCl concentrations.|
|Colonies of Listeria sp. are blue-greenish on Brillians-Listeria-agar medium because they produce a β-glucosidase. There is also a precipitate around colonies of L. monocytogenes and pathogenic strains of L. ivanovii because they have a lecithinase (see the legend to the figure).
||Ruminants (common in sheep), birds, humans etc.|
|Disease (Swedish):||Listerios. Kan hos människa ge ögon-, gastrointestinala (matförgiftning) och hudinfektioner.
|Disease (English):||Listeriosis. Can give eye, gastrointestinal (food poisoning) and skin infections in humans.|
||Neural form: most common in animals (circling disease). Septicemic form: necrotic foci of the liver and myocardium. Metrogenic form: abortion, stillbirth or diseased offspring.|
||The membrane protein internalin, which induces cellular uptake of bacteria by phagocytosis. Listeriolysin O (a hemolysin), which makes it possible for the bacteria to escape from the phagosome before it fuses with a lysosome. The bacteria can polymerise actin by means of the protein Act A, which contributes to their intracellular mobility.|
|NC_003210 ||EGD-e ||2 944 528 ||1c + 0 |
|16S rRNA Seq.:
|Acc-no||Strain||Number of NT||Operon|
|X56153 ||(T) ||1469 ||6 |
|There are 21 species and subspecies described within the genus and all are very similar. L. monocytogenes and the nonpatogenic L. innocua have almost identical 16S rRNA sequences.
||Listeriosis is zoonotic and a notifiable disease in Sweden. L. monocytogenes is classified as a potential biological weapon with the NIAID priority code B. |
|Comment:||Can invade cells and is facultatively intracellular (in monocytes). |
||No. 31, 65|