VetBact logo


Swedish University of Agricultural Sciences

Veterinary bacteriology: information about important bacteria
Veterinary bacteriology

Species/Subspecies: Treponema pallidum subsp. pallidum
Categories: Motile; primarily of interest in human medicin
Etymology: Genus name: A turning thread
Species epithet: Pale, pallid (referrs to the week Gram-staining)
Subspecies epithet: see Species epithet
Significance:T. pallidum subsp. pallidum is globally a very important human pathogen.
  [Very important]   
Type Strain: Not defined
Macromorphology (smell): Cannot be cultivated contiuously in articial media or cell cultures. Is, therfore, propagated intratesicularly in rabbits.
Micromorphology: Tightly coiled (0.1-0.18 x 6-20 µm). Has 2-4 periplasmic flagella at each end of the cell.
Gram +/Gram -:G-
Metabolism: Microaerophilic
Spec. Char.: Generation time: 24-30 h.
Disease:Syphilis, which is a sexually transmitted disease.
Hosts: Human
Clinical Picture:
Genome Sequence:
Acc-noStrainSize (bp)Genome
NC_000919 Nichols 1 138 011 1c + 0 
Three strains have been sequenced. None of the seems to carry plasmids.

16S rRNA Seq.:
Acc-noStrainNumber of NTOperon
M88726 Not defined 1 573 

About 30 different species have been described within the genus Treponema. T. pallidum consists of two additional subspecies: pertenue and endemicum, which both are human patogens. Some researchers regard all these subspecies as separate species, although they are very closely related from a phylogenetic point of view. See the phylogenetic tree (Fig. 100:1). T. paraluiscuniculi is very closely related to T. pallidum.
Legislation: Syphilis is classified in Sweden as a dangerous disease under the Communicable Diseases Act and shall be notified to the County Medical Officer in the County Council and to the Public Health Agency of Sweden.


New names of bacterial phyla

The taxonomic category phylum was previously not regulated by the International Code of Nomenclature of Prokaryotes (ICNP), but now this has changed and it was decided to revise the names of bacterial phyla. All phyla must be written in italics (which has been done on VetBact also before) and have the ending -ota.

Published 2023-03-01. Read more...
The taxonomy of chlamydias

Species within the family Chlamydiaceae were previously divided into two genera Chlamydia and Chlamydophila. However, the differences between these two genera were not that great and many research groups have not accepted this division. Therefore, the genus Chlamydophila has been returned to the genus Chlamydia and this change has now been incorporated in VetBact

Published 2023-03-15. Read more...

Recently Updated

Recent blog posts

Most recent comment

Swedish University of Agricultural Sciences