Naegleria: Difference between revisions

From MicrobeWiki, the student-edited microbiology resource
No edit summary
Line 28: Line 28:


==Cell Structure and Metabolism==
==Cell Structure and Metabolism==
Interesting features of cell structure; how it gains energy; what important molecules it produces.


Naegleria is a common genus of amoebo-flagellate protozoa.  It is a free living organism. Naegleria are not easy to distinguish morphologically. Their species are defined and identified by the shape of their flagella (Scott, 2008).  In contrast to their genus, there are two species of Naegleria that do not develop flagella under laboratory conditions.
Naegleria have a circular ribosomal DNA (Jonckheere, 2002). Naegleria usually have a three stage life cycle. In the first stage, amoeba stage, the morphology of the amoeba is cylindrical, with a size range of 10-30 um, and a contracting area in the rear. This contracting area compresses the cytoplasm allowing locomotion. Naegleria divide by fission.
When Naegleria is diluted naturally by rainwater they rapidly develop into their second stage or flagellate stage. This stage is started from a new transcription from the nucleus (Scott, 2008). Naegleria develop an elongated body and two long anterior flagella. The Naegleria amoeba has to create centrioles that will serve as basal bodies of the flagella. Each flagellum is made up of around 300 proteins that function to allow movement (Scott, 2008). Flagella movement is dependant on the orientation of these proteins in relationship to one another. The flagella do not divide but can revert to the amoeba stage. Then under unfavorable conditions sometimes the initial stage (amoeba stage) can be modify into the third stage that would be a circular cyst (7-14 um) (Bennett, 2008), which is resistant to the hostile environment. In addition to basal bodies, flagella, and a nucleus, Naegleria also have a distinct nuclear envelope, prominent nucleolus, many contractile vacuoles (Chandler & Allan, 1971), cytoplasm, pleomorphic mitochondria and some rough reticulum endoplasmatic.(Patterson et al, 1981).


==Ecology==
==Ecology==

Revision as of 15:42, 5 December 2008

A Microbial Biorealm page on the genus Naegleria

Classification

Higher Order Taxa

Eukaryota; Heterolobosea; Schizopyrenida; Vahlkampfiidae

Species

N. americana, N. andersoni, N. angularis, N. antarctica, N. arctica, N. australiensis, N. canariensis, N. carteri, N. chilensis, N. clarki, N. dobsoni, N. dunnebackei, N. endoi, N. fowleri, N. fultoni, N. galeacystis,

N. gallica, N. gruberi, N. indonesiensis, N. italic, N. jadini, N. jamiesoni, N. laresi, N. lovaniensis, N. mexicana, N. minor, N. morganensis, N. neoantarctica, N. neochilensis, N. neodobsoni, N. neopolaris,

N. niuginesis, N. pagei, N. paradobsoni, N. peruana, N. philippinensis, N. polaris, N. pringsheimi, N. pussardi, N. robinsoni, N. schusteri, N. spitzbergeniensis, N. sturti, N. tenerifensis, N. tihangensis

NCBI: Naegleria

Description and Significance

Describe the appearance, habitat, etc. of the organism, and why you think it is important.

Genome Structure

Describe the size and content of the genome. How many chromosomes? Circular or linear? Other interesting features? What is known about its sequence?


Cell Structure and Metabolism

Naegleria is a common genus of amoebo-flagellate protozoa. It is a free living organism. Naegleria are not easy to distinguish morphologically. Their species are defined and identified by the shape of their flagella (Scott, 2008). In contrast to their genus, there are two species of Naegleria that do not develop flagella under laboratory conditions.

Naegleria have a circular ribosomal DNA (Jonckheere, 2002). Naegleria usually have a three stage life cycle. In the first stage, amoeba stage, the morphology of the amoeba is cylindrical, with a size range of 10-30 um, and a contracting area in the rear. This contracting area compresses the cytoplasm allowing locomotion. Naegleria divide by fission.

When Naegleria is diluted naturally by rainwater they rapidly develop into their second stage or flagellate stage. This stage is started from a new transcription from the nucleus (Scott, 2008). Naegleria develop an elongated body and two long anterior flagella. The Naegleria amoeba has to create centrioles that will serve as basal bodies of the flagella. Each flagellum is made up of around 300 proteins that function to allow movement (Scott, 2008). Flagella movement is dependant on the orientation of these proteins in relationship to one another. The flagella do not divide but can revert to the amoeba stage. Then under unfavorable conditions sometimes the initial stage (amoeba stage) can be modify into the third stage that would be a circular cyst (7-14 um) (Bennett, 2008), which is resistant to the hostile environment. In addition to basal bodies, flagella, and a nucleus, Naegleria also have a distinct nuclear envelope, prominent nucleolus, many contractile vacuoles (Chandler & Allan, 1971), cytoplasm, pleomorphic mitochondria and some rough reticulum endoplasmatic.(Patterson et al, 1981).

Ecology

Habitat; symbiosis; contributions to the environment.

Pathology

How does this organism cause disease? Human, animal, plant hosts? Virulence factors, as well as patient symptoms.

Bioremediation

Current Research

Enter summarries of the most rescent research here--at least three required

References

[Sample reference] Takai, K., Sugai, A., Itoh, T., and Horikoshi, K. "Palaeococcus ferrophilus gen. nov., sp. nov., a barophilic, hyperthermophilic archaeon from a deep-sea hydrothermal vent chimney". International Journal of Systematic and Evolutionary Microbiology. 2000. Volume 50. p. 489-500.

Edited by student of Dr. Kirk Bartholomew