Spirochaete

Spirochaetes is a phylum of distinctive Gram-negative bacteria, which have long, helically coiled cells.^[1] Spirochetes are chemoheterotrophic in nature, with lengths between 5 and 250 µm and diameters around 0.1-0.6 µm.^{[citation needed]}

Additional recommended knowledge

Weighing the right way

How to ensure accurate weighing results every day?

How to quickly check pipettes?

Spirochaetes are distinguished from other bacterial phyla by the location of their flagella, sometimes called axial filaments, which run lengthwise between the cell membrane and outer membrane. These cause a twisting motion which allows the spirochaete to move about.

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^[2]
• Borrelia burgdorferi, which causes Lyme disease
• Borrelia recurrentis, which causes relapsing fever^[3]
• Treponema pallidum, which causes syphilis

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

Cavalier-Smith has postulated that the Spirochaetes belong in a larger clade called Gracilicutes.^[4]

Historical

Salvarsan, the first antibiotic in medical history, was effective against spirochaetes only and was primarily used to cure syphilis.

It has been suggested by biologist Lynn Margulis that eukaryotic flagella were derived from symbiotic spirochaetes, but few biologists accept this, as there is no close structural similarity between the two.

See also

• Flagellum
• Treponema pallidum
• Lyme disease microbiology
• Borrelia
• Bacteriology
• Prokaryote

References