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Veterinary bacteriology: information about important bacteria
Veterinary bacteriology

Species/Subspecies: Yersinia ruckeri
Categories: Causes hemolysis; in the normal flora; notifiable diseases and bacteria
Etymology: Genus name: named after the French bacteriologist A.J.E. Yersin, who in 1894 first isoleted the bacterium which causes the plague.
Species epithet: named after R.R. Rucker, who studied the red mouth disease and its causative agent.
Significance:The disease has been has been found in farmed fish since 1985 in Sweden and recently also in wild fish.
  [Of minor importance]   
Type Strain: ATCC 29473 = CCUG 14190 = NCTC 12986
Macromorphology (smell): Small (0.5-1 mm in diameter) white greyish colonies
Micromorphology: Motile rods (1 x 2-3 µm) with peritrichous flagella
Gram +/Gram -:G-
Metabolism: Facultatively anaerobic
Other Enzymes: Tryptophanase - and urease -
Fermentation of carbohydrates: Glucose(gas) -, Mannitol +, Rhamnose -, Sorbitol - and Sucrose -. Cf. other Yersinia spp.
Spec. Char.:
Vector: Certain other fish species
Disease:Enteric redmouth (ERM) disease (or just redmouth disease) or yersiniosis
Hosts: Freshwater and marine fish, particularly salmonids
Clinical Picture: Subcutaneous hemorrhaging of the mouth, fins, and eyes and also on internal organs.
Virulence Factors: Produce a so-called siderophore (for iron uptake) called ruckerbactin.
16S rRNA Seq.:
Acc-noStrainNumber of NTOperon
AF366385 ATCC 29473T 1 461  

Within the genus Yersinia, 20 species have been described. All species belong to the family Enterobacteriaceae.
Comment:Red mouthe disease is a notifyable disease in Sweden.
Reference(s): No. 174


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