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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 25 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 taxa within the classification category phylum

During October 2021, an article was published by A. Oren och G.M. Garrity, in which new names are proposed for a number of taxa within the classification category phylum. This has resulted in many discussions in social media about whether it was really necessary to make these changes, which have created confusion among microbiologists and other professionals who come into contact with bacteriology.

Published 2022-09-28. Read more...

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