Naegleria
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
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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
Naegleria can be used in wastewater treatment by participating in anaerobic degradation of organic matter. This is a complex process where microbial organisms, along with biochemical and physic-chemical characteristics work together treating Biodegradable wastewaters.
Researchers have performed experiments in anaerobic continuous stirred tank reactors containing protozoa (some of them from the Naegleria genus), bacteria and archeae organisms. This group of microbes has the ability to degrade natural polymers such as: polysaccharides, proteins, nucleic acids and lipids into methane and carbon dioxide in the absence of oxygen. In this process protozoa reduce MLSS (mix liquid suspended solids), most commonly known as a biomass, and increase sludge activity. Protozoa in anaerobic wastewater treatment increase COD (chemical oxygen demand) removal and increase methane production. Also, Naegleria and other protozoa have the ability to feed on organic matter and not just bacteria. (Priya et al, 2007)
Current Research
Enter summarries of the most rescent research here--at least three required
References
Edited by student of Dr. Kirk Bartholomew
