Naegleria is a genus consisting of 47 described species of protozoa often found in warm aquatic environments as well as soil habitats worldwide. It has three life cycle forms: the amoeboid stage, the cyst stage, and the flagellated stage, and has been routinely studied for its ease in change from amoeboid to flagellated stages.
History
In 1899, Franz Schardinger discovered an amoeba that had the ability to transform into a flagellated stage. He named the organism Amoeba gruberi,
Habitat and ecology
Naegleria is found worldwide in typically aerobic warm aquatic environments (freshwater such as lakes and rivers) and soil habitats. The few species that are pathogenic seem to be thermophilic, preferring warmer temperatures such as those in nuclear power plant cooling systems. One species, Naegleria fowleri, can be an opportunistic and usually fatal pathogen of humans if it enters the nasal cavity.
Description
Morphology/anatomy
Naegleria are free-living amoebae, with some species being opportunistic pathogens. It has a nucleus with a prominent nucleolus. The double wall consists of a thick endocyst and a thin endocyst. Notably, five species have never been observed in this flagellate life stage. It has a 33% GC content, and 57.8% of the genome is coding with about 36% consisting of introns. It is typically a free living thermophile, but is a deadly parasite if it encounters the right host. Naegleria have been observed to cause central nervous system (CNS) infections in animals such as mice, rats, squirrels, guinea pigs, sheep, as well as infections in the gills of fish.
- Naegleria martinezi
- Naegleria mexicana
- Naegleria minor
- Naegleria morganensis
- Naegleria neoantarctica
- Naegleria neochilensis
- Naegleria neodobsoni
- Naegleria neopolaris
- Naegleria niuginensis
- Naegleria pagei
- Naegleria paradobsoni
- Naegleria peruana
- Naegleria philippinensis
- Naegleria polaris
- Naegleria pringsheimi
- Naegleria pussardi
- Naegleria robinsoni
- Naegleria schusteri
- Naegleria spitzbergeniensis
- Naegleria sturti
- Naegleria tenerifensis
- Naegleria tihangensis
References
Further reading
External links
- Naegleria - Centers for Disease Control and Prevention
- http://www.bms.ed.ac.uk/research/others/smaciver/naegleria.htm