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Veterinary bacteriology: information about important bacteria
Veterinary bacteriology

Species/Subspecies: Clostridium piliforme
Categories: Spore forming; motile
Etymology: Genus name: a small spindle.
Species epithet: hair-shaped (pilus means hair).
Significance:  [Of minor importance]   
Alternative Species Name(s):Bacillus piliformis
Type Strain: Has not been defined.
Macromorphology (smell): Cannot be cultivated on artificial media.
Micromorphology: Large spore forming and filamentous rod (0.5 x 8-10 µm).
Gram +/Gram -:G- under aerobe conditions, but has actually a G+ cell wall.
Metabolism: Anaerobic
Spec. Char.: Obligate intracellular bacterium.
Disease:Tyzzer's disease.
Hosts: Primarely rodents, but has also been reported from foals, calf, dog and cat.
Clinical Picture: Most infections are subclinical, but watery diarrhea with high mortality occurs.
Virulence Factors: Virulence mechanisms are poorly understood, but C.piliforme seems to produce an exotoxin (cytotoxin).
16S rRNA Seq.:
Acc-noStrainNumber of NTOperon
L07416 Ej definierad 1455  

About 175 different species have been described within the genus Clostridium. C. piliforme is like C. difficile and C. sordellii only distantly related to other clostridia as shown in the phylogenetic tree (see Fig. 28:1). However, the names have been changed for the two latter, which are now called Clostridioides difficile and Paeniclostridium sordellii, respectively. The reason why C. piliforme has not been renamed is probably that no type strain has been defined because the bacterium can not be grown.
Comment:Cannot be cultivated on artificial media. The species name has not been approved because no type strain has been defined.
Reference(s): No. 133


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