Spirochaete

Spirochaetes
Spirochaetes.  Numbered ticks are 10 µm apart.  Gram-stained.
Treponema pallidum spirochaetes.
Scientific classification
Domain:	Bacteria
Phylum:	Spirochaetae Cavalier-Smith 2002
Class:	Spirochaetes Cavalier-Smith 2002
Order:	Spirochaetales Buchanan 1917
Families & Genera
?Exilispira Imachi et al. 2008 Brevinemataceae Paster 2012 Brevinema Defosse et al. 1995 Brevinema andersonii Defosse et al. 1995 Brachyspiraceae Paster 2012 Brachyspira Hovind-Hougen et al. 1983 Leptospiraceae Hovind-Hougen 1979 emend. Levett et al. 2005 Leptonema Hovind-Hougen 1983 Leptospira Noguchi 1917 emend. Faine and Stallman 1982 Turneriella Levett et al. 2005 Spirochaetaceae Swellengrebel 1907 Borrelia Swellengrebel 1907 Clevelandina ♦ Bermudes et al. 1988 Cristispira ♪ Gross 1910 Diplocalyx ♦ (ex Gharagozlou 1968) Bermudes et al. 1988 Hollandina ♦ (ex To et al. 1978) Bermudes et al. 1988 Pillotina ♦ (ex Hollande and Gharagozlou 1967) Bermudes et al. 1988 Sphaerochaeta Ritalahti et al. 2012 Spirochaeta Spirochaeta Ehrenberg 1835 emend. Pikuta et al. 2009 Spironema ♠ Turk et al. 1999 Treponema Schaudinn 1905
Synonyms
Phylum Spirochaetes Garrity and Holt, 2001

Cross section of a spirochaete cell

Spirochaetes English pronunciation: /ˈspʌɪrə(ʊ)kiːt/^[1] (also spelled spirochetes) belong to a phylum of distinctive diderm (double-membrane) bacteria, most of which have long, helically coiled (corkscrew-shaped or spiraled, hence the name) cells.^[2] Spirochaetes are chemoheterotrophic in nature, with lengths between 3 and 500 µm and diameters around 0.09 to at least 3 µm.^[3]

Spirochaetes are distinguished from other bacterial phyla by the location of their flagella, sometimes called axial filaments, which run lengthwise between the bacterial inner membrane and outer membrane in periplasmic space. These cause a twisting motion which allows the spirochaete to move about. When reproducing, a spirochaete will undergo asexual transverse binary fission.

Most spirochaetes are free-living and anaerobic, but there are numerous exceptions.

Spirochetes may cause dementia and may be involved in the pathogenesis of Alzheimer's disease.^[4]

Classification

The spirochaetes are divided into three families (Brachyspiraceae, Leptospiraceae, and Spirochaetaceae), all placed within a single order (Spirochaetales). Disease-causing members of this phylum include the following:

• Leptospira species, which causes leptospirosis^[5]
• Borrelia burgdorferi, B. garinii, and B. afzelii, which cause Lyme disease
• Borrelia recurrentis, which causes relapsing fever^[6]
• Treponema pallidum subspecies which cause treponematoses such as syphilis and yaws.
• Brachyspira pilosicoli and Brachyspira aalborgi, which cause intestinal spirochaetosis^[7]

Cavalier-Smith has postulated that the Spirochaetes belong in a larger clade called Gracilicutes.^[8]

Spirochaetes are gram-negative bacteria.

Phylogeny

The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN)^[9] and National Center for Biotechnology Information (NCBI)^[10] and the phylogeny is based on 16S rRNA-based LTP release 111 by 'The All-Species Living Tree' Project.^[11]

Leptospiraceae Turneriella parva (Hovind-Hougen et al. 1982) Levett et al. 2005 Leptonema illini Hovind-Hougen 1983 Leptospira Noguchi 1917 emend. Faine and Stallman 1982 Brevinema andersonii Defosse et al. 1995 Brachyspira Hovind-Hougen et al. 1982 Exilispira thermophila Imachi et al. 2008 Spirochaetaceae ?Clevelandina reticulitermitidis ♦ Bermudes et al. 1988 ?Cristispira pectinis ♪ Gross 1910 ?Diplocalyx calotermitidis ♦ (ex Gharagozlou 1968) Bermudes et al. 1988 ?Hollandina pterotermitidis ♦ (ex To et al. 1978) Bermudes et al. 1988 ?Pillotina calotermitidis ♦ (ex Hollande and Gharagozlou 1967) Bermudes et al. 1988 Spironema culicis ♠ Turk et al. 1999 Spirochaeta [paraphyletic incl. Borrelia, Sphaerochaeta and Treponema]

Notes:
♦ Type strain lost or not available
♪ Prokaryotes where no pure (axenic) cultures are isolated or available, i. e. not cultivated or can not be sustained in culture for more than a few serial passages
♠ Strains found at the National Center for Biotechnology Information (NCBI) but not listed in the List of Prokaryotic names with Standing in Nomenclature (LSPN)

Historical

Salvarsan, the first partially organic synthetic antimicrobial drug in medical history, was effective against spirochaetes only and was primarily used to cure syphilis.

See also

• Bacteriology
• Borrelia
• Flagellum
• Lyme disease microbiology
• Pinta (disease)
• Prokaryote
• Treponema pallidum
• Brevinema andersonii
• Syphilis

References

1. spirochaete - Oxford Dictionaries
2. Ryan KJ; Ray CG (editors) (2004). Sherris Medical Microbiology (4th ed.). McGraw Hill. ISBN 0-8385-8529-9.
3. Margulis, L.; Ashen, J. B.; Solé, M.; Guerrero, R. (1993-08-01). "Composite, large spirochetes from microbial mats: spirochete structure review" (PDF). Proceedings of the National Academy of Sciences 90 (15): 6966–6970. ISSN 0027-8424. PMC 47056. PMID 8346204.
4. Miklossy, Judith (2011-08-04). "Alzheimer's disease - a neurospirochetosis. Analysis of the evidence following Koch's and Hill's criteria". Journal of Neuroinflammation 8: 90. doi:10.1186/1742-2094-8-90. ISSN 1742-2094. PMC 3171359. PMID 21816039.
5. McBride A, Athanazio D, Reis M, Ko A (2005). "Leptospirosis". Current Opinion in Infectious Diseases 18 (5): 376–86. doi:10.1097/01.qco.0000178824.05715.2c. PMID 16148523.
6. Schwan T (1996). "Ticks and Borrelia: model systems for investigating pathogen-arthropod interactions". Infect Agents Dis 5 (3): 167–81. PMID 8805079.
7. Amat Villegas I, Borobio Aguilar E, Beloqui Perez R, de Llano Varela P, Oquiñena Legaz S, Martínez-Peñuela Virseda JM (January 2004). "[Colonic spirochetes: an infrequent cause of adult diarrhea]". Gastroenterol Hepatol (in Spanish) 27 (1): 21–3. PMID 14718105.
8. Cavalier-Smith, T. (2006). "Rooting the tree of life by transition analyses". Biology Direct 1 (19): 19. doi:10.1186/1745-6150-1-19. PMC 1586193. PMID 16834776.
9. J.P. Euzéby. "Spirochaetes". List of Prokaryotic names with Standing in Nomenclature (LPSN). Retrieved 2013-03-20.
10. Sayers; et al. "Spirochaetes". National Center for Biotechnology Information (NCBI) taxonomy database. Retrieved 2013-03-20.
11. 'The All-Species Living Tree' Project."16S rRNA-based LTP release 111 (full tree)" (PDF). Silva Comprehensive Ribosomal RNA Database. Retrieved 2013-03-20.

External links

• Introduction to the Spirochetes University of California Museum of Paleontology (UCMP)