Francisella tularensis
Template:Infobox - bakterie Francisella tularensis is an aerobic, gram-negative, non-sporulating bacterium.
Morphology and physiology[edit | edit source]
The cell has the shape of a rod with a length of 0.7 µm. It is immobile, encapsulated, non-sporulating.[1]
Cultivation[edit | edit source]
Francisella tularensis is difficult to culture, growing on blood agar with glucose and cysteine (cysteine, glutamine, histidine and thimine are important growth factors for the bacteria). Medium with coagulated egg yolks is also suitable; it multiplies well in the endothelium of the yolk sac of chicken embryos. The colonies are small and translucent at first, later opaque. Sugar fermentation is weak.
Toxins[edit | edit source]
Virulent strains have a surface antigenic complex called factor Vi; in the cell wall of F. tularensis is a low potent endotoxin, thermolabile toxic protein has also been isolated.
Disease[edit | edit source]
Francisella tularensis causes tularemia. Humans can be infected by transmission from rodents:
- bite by an infected tick
- water contaminated with feces or carcasses,
- when processing contaminated straw, hay or cereals.
Diagnostics[edit | edit source]
- For the cultivation we use material from the primary lesion, sputum, nodal puncture; in the bacteremia phase, we try to capture the microbe from the blood.
- Isolation on susceptible laboratory animals - after death, material from lesions is cultivated on agars.
- Immunofluorescence can be used for rapid diagnosis.
Links[edit | edit source]
Related articles:[edit | edit source]
Sources:[edit | edit source]
- BEDNÁŘ, M, V FRAŇKOVÁ a J SCHINDLER, et al. Lékařská mikrobiologie – bakteriologie, virologie, parazitologie. 1. vydání. Praha : Marvil, 1996. 558 s. ISBN 80-238-0297-6.
- ↑ BEDNÁŘ, Marek – SOUČEK, A – FRAŇKOVÁ, V. LÉKAŘSKÁ MIKROBIOLOGIE : Bakteriologie, virologie, parazitologie. 1. edition. Brno : Triton, 1996. 560 pp. pp. 255. ISBN 859-4-315-0528-0.
