German: Leptospiren
Leptospira are bacteria that belong to the genus of spirochaetes. The cells of bacteria from this genus has cells that are wound spirally. Infectious diseases that can be cause by leptospira are referred to as leptospirosis.
Even though there have already been more than 200 different species of this genus described, all of them significant morphologic similarities. They all are gram negative, spirally shaped bacteria which often display hook-shaped or button-like thickening on their ends. They are very thin, the diameter is only about 0,1 μm, and their length varies between 6 and 20 μm. The length variation is also accompanied by a difference in the number of spirals.
The extremely small diameter allows leptospira to pass through membrane pores whose size is larger than 0,2 μm. The size also makes it difficult to remove leptospira from liquids with the often used membrane filters in microbiology. The Bacteria does not form endospores and can move actively through rotations around its body axis.
Leptospira, pathogenic as well as saprophytic are with the exception of the Antarctica ubiquitous . The requirement for colonization are a high humidity and a neutral pH. Natural habitats of the bacteria include stagnant water bodies such as lakes, swamps, puddles and ponds. Some types live [parasite|parasitic]] in humans and animals but there are also types that live freely in the environment.
The metabolism of leptospira is obligatory aerobic, meaning that reproduction only occurs in the presence of oxygen. For its growth the optimal pH value is 7,2-7,6 and the optimal temperature is between 28 and 30 °C. The bacterium prefers culture medium that contains long chained fatty acids because of its chemoorganic-heterotrophic metabolism. The cell division occurs slowly having a generation time of 7 to 16 hours.
Tags: Bacteria, Bacteriology, Infectious disease, Pathogen
Specialties: Biology
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Student of human medicine
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